CITRONELA

Anti-Candida activity of Brazilian medicinal plants.

Autores: Marta Cristina Teixeira Duarte, Glyn Mara Figueira, Adilson Sartoratto, Vera Lúcia Garcia Rehder, Camila Delarmelina | Ano: 2005 | Database: pubmed

Resumo: Essential oils and ethanolic extracts from the leaves and/or roots of 35 medicinal plants commonly used in Brazil were screened for anti-Candida albicans activity. The oils were obtained by water-distillation using a Clevenger-type system. Essential oils from 13 plants showed anti-Candida activity, including Aloysia triphylla, Anthemis nobilis, Cymbopogon martini, Cymbopogon winterianus, Cyperus articulatus, Cyperus rotundus, Lippia alba, Mentha arvensis, Mikania glomerata, Mentha piperita, Mentha sp., Stachys byzantina, and Solidago chilensis. The ethanol extract was not effective at any of the concentrations tested. Chemical analyses showed the presence of compounds with known antimicrobial activity, including 1,8-cineole, geranial, germacrene-D, limonene, linalool, and menthol.

Resultados: N/A

Conclusão: N/A

Anti-Candida activity of Brazilian medicinal plants.

Autores: Marta Cristina Teixeira Duarte, Glyn Mara Figueira, Adilson Sartoratto, Vera Lúcia Garcia Rehder, Camila Delarmelina | Ano: 2005 | Database: pubmed

Resumo: Essential oils and ethanolic extracts from the leaves and/or roots of 35 medicinal plants commonly used in Brazil were screened for anti-Candida albicans activity. The oils were obtained by water-distillation using a Clevenger-type system. Essential oils from 13 plants showed anti-Candida activity, including Aloysia triphylla, Anthemis nobilis, Cymbopogon martini, Cymbopogon winterianus, Cyperus articulatus, Cyperus rotundus, Lippia alba, Mentha arvensis, Mikania glomerata, Mentha piperita, Mentha sp., Stachys byzantina, and Solidago chilensis. The ethanol extract was not effective at any of the concentrations tested. Chemical analyses showed the presence of compounds with known antimicrobial activity, including 1,8-cineole, geranial, germacrene-D, limonene, linalool, and menthol.

Resultados: N/A

Conclusão: N/A

Anthelmintic activity of Eucalyptus citriodora essential oil and its major component, citronellal, on sheep gastrointestinal nematodes/ Atividade anti-helmíntica do óleo essencial de Eucalyptus citriodora e seu componente majoritário, citronelal, sobre nematoides gastrintestinais de ovinos

Autores: Araújo-Filho, José Vilemar de; Ribeiro, Wesley Lyeverton Correia; André, Weibson Paz Pinheiro; Cavalcante, Géssica Soares; Rios, Thays Tabosa; Schwinden, Gabriela Maria; Rocha, Letícia Oliveira da; Macedo, Iara Tersia Freitas; Morais, Selene Maia de; Bevilaqua, Claudia Maria Leal; Oliveira, Lorena Mayana Beserra de | Ano: 2019 | Database: LILACS

Resumo: Abstract This study aimed to evaluate the anthelmintic activity of Eucalyptus citriodora essential oil and citronellal on sheep gastrointestinal nematodes. Essential oil composition was determined by gas chromatography mass spectrometry. The substances were evaluated in vitro using adult worm motility test (AWMT) and transmission electron microscopy (TEM). The acute toxicity test in mice and the fecal egg count reduction test (FECRT) in sheep were performed. Citronellal was confirmed as the essential oil major constituent (63.9%). According to the AWMT, 2 mg/mL of essential oil and citronellal completely inhibited Haemonchus contortus motility at 6 h post exposure. H. contortus exposed to essential oil and citronellal exhibited internal ultrastructural modifications. The lethal dose 50 values in mice were 5,000 and 2,609 mg/kg for essential oil and citronellal, respectively. E. citriodora essential oil reduced sheep epg at 14 days post treatment by 69.5% (P<0.05). No significant differences were observed in epg between the citronellal and negative control groups (P>0.05). The interaction between citronellal and other constituents in the essential oil may be relevant for its in vivo anthelmintic activity. Thus, E. citriodora essential oil and citronellal pharmacokinetic studies may help elucidate the anthelmintic activity of these compounds.

Resultados: N/A

Conclusão: N/A

The Antifungal Activity of Cinnamon-Litsea Combined Essential Oil against Dominant Fungal Strains of Moldy Peanut Kernels.

Autores: Yijun Liu, Ruolan Wang, Lingli Zhao, Shanshan Huo, Shichang Liu, Hanxiao Zhang, Akio Tani, Haoxin Lv | Ano: 2022 | Database: pubmed

Resumo: The antifungal activity of cinnamon (Cinnamomum cassia Presl), litsea [Litsea cubeba (Lour.) Pers.], clove (Syzygium aromaticum L.), thyme (Thymus mongolicus Ronn.) and citronella (Cymbopogon winterianus Jowitt) essential oils (EOs) against the dominant fungi isolated from moldy peanuts was investigated in this research. Firstly, strain YQM was isolated and identified by morphological characterization and 18S rRNA gene sequence analysis to be Aspergillus flavus (A. flavus). Next, antifungal effects of single or mixed EOs on strain YQM were evaluated by the inhibition zone test. The cinnamon-litsea combined essential oil (CLCEO, Vcinnamon oil:Vlitsea oil = 3:5) displayed the best antifungal effect on strain YQM. The chemical composition of CLCEO was identified and quantified by gas chromatograph-mass spectrometry (GC-MS), and results revealed that the major components of CLCEO were cinnamaldehyde and citral. Finally, the effect of EOs on the microstructure of strain YQM mycelia was observed under scanning electron microscope (SEM). The mycelia exposed to cinnamon essential oil (CEO) and litsea essential oil (LEO) were partly deformed and collapsed, while the mycelia treated with CLCEO were seriously damaged and the deformation phenomena such as shrinking, shriveling and sinking occurred. Therefore, CLCEO has great potential for using as anti-mildew agents during peanut storage.

Resultados: N/A

Conclusão: N/A

Atividade Inibitória de Óleos Essenciais Vegetais Frente à Candida glabrata, Resistente a Fluconazol/ Inhibitory Activity of Essential Oils Extracted From Plants Against Fluconazole-Resistant Candida glabrata

Autores: Almeida, Leopoldina de Fátima Dantas de; Paula, Jacqueline Felipe de; Almeida-Marques, Rossana Vanessa Dantas de; Cavalcanti, Yuri Wanderley; Hebling, Josimeri | Ano: 2017 | Database: LILACS

Resumo: Introdução: A candidose oral é uma infecção fúngica que se manifesta frequentemente em pacientes imunocomprometidos ou naqueles que fazem uso de prótese dental removível, associada a hábitos de higiene deficitários. Antifúngicos sintéticos, a exemplo do fluconazol, são utilizados no tratamento desta infecção; entretanto algumas cepas apresentam resistência a estes fármacos. Objetivo: Este estudo avaliou o efeito antifúngico dos óleos essenciais de Persea americana (abacate), Cinnamomumzeylanicum (canela ­ folha), Cinnamomumcassia (canela ­ casca) e Cymbopogonwinterianus (citronela), frente à Candidaglabrata. Material e Métodos: O screening da atividade antifúngica dos óleos foi determinado por difusão em meio sólido, utilizando um inóculofúngico ajustado em 1 × 106 UFC/mL. A Concentração Inibitória Mínima (CIM) foi determinada pela técnica da microdiluição. Os óleos essenciais foram avaliados em concentrações entre 1000 µg/mL e 7,81 µg/mL, enquanto que os fármacos Fluconazol e Nistatina foram avaliados nas concentrações que entre 64 µg/mL e 0,5 µg/mL. Resultados: Os halos de inibição mensurados variaram entre 8,2 e 9,2 mm de diâmetro, respectivamente para C. winterianuse C. cassia.Os óleos essenciais de C. winterianuse C. zeylanicumapresentaram CIM de 125 µg/mL, enquanto a CIM de C. cassiafoi 62,5 µg/mL. A CIM dos fármacos utilizados como controle foram estabelecidasem 16 µg/mL(fluconazol) e 2,0 µg/mL(nistatina). O óleo essencial de P. americana não apresentou atividade antifúngica nas concentrações avaliadas. Conclusão: Conclui-se que os óleos essenciais de canela (casca e folha) e citronela apresentaram atividade antifúngica frente a cepa de C. glabrataresistente a fluconazol. (AU)

Resultados: N/A

Conclusão: N/A

Synergistic antimicrobial activities of essential oil vapours against Penicillium corylophilum on a laboratory medium and beef jerky.

Autores: Hyegeun Ji, Hoikyung Kim, Larry R Beuchat, Jee-Hoon Ryu | Ano: 2019 | Database: pubmed

Resumo: This study was done to determine the antifungal activities of essential oil (EO) vapours of 97 plants against Penicillium corylophilum and to test combinations of EO vapours for synergistic antifungal effects. Among 97 commercially available EOs extracted from plant parts, garlic, cinnamon bark, may chang (mountain pepper), citronella, thyme thymol, oregano, spearmint, and thyme linalool EO vapours exhibited relatively strong antifungal activities. The minimal inhibitory concentrations of these EO vapours were 0.0390-0.6250 μL/mL. A combination of cinnamon bark, citronella, and may chang EO vapours, as well as a combination of cinnamon bark and citronella EO vapours, showed synergistic inhibitory activities to P. corylophilum on a laboratory medium. A combination of cinnamon bark, citronella, and may chang EO vapours had synergistic activity in inhibiting growth of P. corylophilium on beef jerky. Observations reported here provide basic information valuable when developing strategies to inhibit the growth of P. corylophilum and possibly other moderately xerophilic molds on intermediate-moisture foods.

Resultados: N/A

Conclusão: N/A

Effects of Cymbopogon winterianus Jowitt ex Bor essential oil on the growth and morphogenesis of Trichophyton mentagrophytes/ Efeitos do óleo essencial de Cymbopogon winterianus Jowitt ex Bor no crescimento e na morfogênese de Trichophyton mentagrophytes

Autores: Pereira, Fillipe de Oliveira; Wanderley, Paulo Alves; Viana, Fernando Antônio Cavalcanti; Lima, Rita Baltazar de; Sousa, Frederico Barbosa de; Santos, Sócrates Golzio dos; Lima, Edeltrudes de Oliveira | Ano: 2011 | Database: LILACS

Resumo: Trichophyton mentagrophytes is a fungus causative agent of dermatophytosis, affecting humans worldwide. This has driven the search for products for the treatment of these infections. Accordingly, the aim of this study was to investigate the antifungal activity of the Cymbopogon winterianus essential oil against T. mentagrophytes. The antifungal tests consisted of antifungal screening, determination of MIC and MFC, analysis of the essential oil's effects on mycelial growth, germination of fungal spores, fungal viability, morphogenesis, cell wall (test with sorbitol) and cell membrane (cell leakage test) of T. mentagrophytes. Upon screening, the oil inhibited all strains, with zones of growth inhibition of 24-28 mm in diameter. The MIC was 312 μg/mL and CFM was 2500 μg/mL for almost all the strains tested. There were morphological changes in the conidia group, form and pigmentation of hyphae. The antifungal action of the product does not involve the cell wall and its action may involve the fungal plasma membrane. It is concluded that C. winterianus essential oil constitutes a potential antifungal product, especially for the treatment of dermatophytosis.

Resultados: N/A

Conclusão: N/A

Growth inhibition and morphological alterations of Trichophyton rubrum induced by essential oil from Cymbopogon winterianus Jowitt ex Bor

Autores: Pereira, Fillipe de Oliveira; Wanderley, Paulo Alves; Viana, Fernando Antônio Cavalcanti; Lima, Rita Baltazar de; Sousa, Frederico Barbosa de; Lima, Edeltrudes de Oliveira | Ano: 2011 | Database: LILACS

Resumo: Trichophyton rubrum is one of the most common fungi causer of dermatophytosis, mycosis that affect humans and animals around the world. Researches aiming new products with antifungal activity become necessary to overcome difficulties on treatment of these infections. Accordingly, this study aimed to investigate the antifungal activity of essential oil from Cymbopogon winterianus against the dermatophyte T. rubrum. The antifungal screening was performed by solid medium diffusion method with 16 T. rubrum strains, minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) were determined using the microdilution method. The effects on mycelial dry weight and morphology were also observed. Screening showed essential oil in natura inhibited all the tested strains, with inhibition zones between 24-28 mm diameter. MIC50 and MIC90 values of the essential oil were 312 µg/mL for nearly all the essayed strains (93.75 percent) while the MFC50 and MFC90 values were about eight times higher than MIC for all tested strains. All tested essential oil concentrations managed to inhibit strongly the mycelium development. Main morphological changes on the fungal strains observed under light microscopy, which were provided by the essential oil include loss of conidiation, alterations concerning form and pigmentation of hyphae. In the oil presence, colonies showed folds, cream color and slightly darker than the control, pigment production was absent on the reverse and with evident folds. It is concluded that C. winterianus essential oil showed activity against T. rubrum. Therefore, it could be known as potential antifungal compound especially for protection against dermatophytosis.

Resultados: N/A

Conclusão: N/A

The Antifungal Activity of Cinnamon-Litsea Combined Essential Oil against Dominant Fungal Strains of Moldy Peanut Kernels.

Autores: Yijun Liu, Ruolan Wang, Lingli Zhao, Shanshan Huo, Shichang Liu, Hanxiao Zhang, Akio Tani, Haoxin Lv | Ano: 2022 | Database: pubmed

Resumo: The antifungal activity of cinnamon (Cinnamomum cassia Presl), litsea [Litsea cubeba (Lour.) Pers.], clove (Syzygium aromaticum L.), thyme (Thymus mongolicus Ronn.) and citronella (Cymbopogon winterianus Jowitt) essential oils (EOs) against the dominant fungi isolated from moldy peanuts was investigated in this research. Firstly, strain YQM was isolated and identified by morphological characterization and 18S rRNA gene sequence analysis to be Aspergillus flavus (A. flavus). Next, antifungal effects of single or mixed EOs on strain YQM were evaluated by the inhibition zone test. The cinnamon-litsea combined essential oil (CLCEO, Vcinnamon oil:Vlitsea oil = 3:5) displayed the best antifungal effect on strain YQM. The chemical composition of CLCEO was identified and quantified by gas chromatograph-mass spectrometry (GC-MS), and results revealed that the major components of CLCEO were cinnamaldehyde and citral. Finally, the effect of EOs on the microstructure of strain YQM mycelia was observed under scanning electron microscope (SEM). The mycelia exposed to cinnamon essential oil (CEO) and litsea essential oil (LEO) were partly deformed and collapsed, while the mycelia treated with CLCEO were seriously damaged and the deformation phenomena such as shrinking, shriveling and sinking occurred. Therefore, CLCEO has great potential for using as anti-mildew agents during peanut storage.

Resultados: N/A

Conclusão: N/A

Atividade antifúngica de três óleos essenciais sobre cepas de candida/ Antifungal activity of three essential oils on candida strains

Autores: Cavalcanti, Yuri W; Almeida, Leopoldina F. D; Padilha, Wilton W. N | Ano: 2011 | Database: LILACS

Resumo: Objetivou-se avaliar a atividade antifúngica dos óleos essenciais de Melaleuca alternifólia (melaleuca), Cymbopogon winterianus (citronela), e Rosmarinus officinalis (alecrim) sobre Candida albicans (ATCC289065), C. albicans (ATCC40227), C. krusei (ATCC40147), C. tropicalis (ATCC40042) e C. tropicalis (ATCC13803). Determinou-se a atividade antifúngica pela Concentração Inibitória Mínima (CIM) e Concentração Fungicida Mínima (CFM), obtidas através das técnicas de microdiluição e de esgotamento, respectivamente. Em microplacas de 96 poços foram inseridos 100?L de caldo Sabouraud-Dextrose duplamente concentrado, 100?L da diluição dos óleos essenciais e 10?L do inoculo fúngico (1,5x106 microrganismos/mL). Realizou-se diluição seriada dos produtos partindo-se da concentração inicial de 8% até 0,0625%. A CIM correspondeu a menor diluição na qual se verificou ausência de crescimento fúngico visível. Realizou-se a semeadura, em Ágar Sabouraud-Dextrose, de 10?L das diluições correspondentes a CIM e duas imediatamente anteriores. Os testes foram realizados em triplicata e a Nistatina (100.000UI/mL) serviu de controle. Procedeu-se análise estatística pelos testes Kruskal-Wallis e Dunn. Para R. officinalis, observou-se melhor desempenho frente C. albicans (ATCC289065) e C. tropicalis (ATCC40042), com CIM e CFM iguais a 0,5626mg/ mL. M. alternifólia e C. winterianus apresentaram melhor desempenho frente C. tropicalis (ATCC40042), com CIM e CFM iguais a 0,5626mg/mL. O óleo essencial de R. officinalis apresentou atividade antifúngica estatisticamente diferente (p<0,05), com menores valores de CIM e CFM. Não se observou diferença estatística (p>0,05) para a ação de M. alternifólia e C. winterianus. Concluiu-se que os produtos avaliados exerceram atividade antifúngica sobre Candida, destacando-se o óleo essencial de R. officinalis, com menores CIM e CFM.

Resultados: N/A

Conclusão: N/A

Rendimento, composição química e atividade antilisterial de óleos essenciais de espécies de Cymbopogon/ Yield, chemical composition and antilisterial activity of essential oils from Cymbopogon species

Autores: Oliveira, M. M. M; Brugnera, D. F; Cardoso, M. G; Guimarães, L. G. L; Piccoli, R. H | Ano: 2011 | Database: LILACS

Resumo: Objetivou-se determinar o rendimento, a composição química e avaliar a atividade antilisterial dos óleos essenciais de Cymbopogon citratus (DC.) Stapf. (capim-limão) e Cymbopogon nardus (L.) Rendle (capim-citronela), puros e em combinação. A obtenção dos óleos essenciais foi realizada a partir de folhas frescas, empregando-se a técnica de hidrodestilação e utilizando-se aparelho de Clevenger modificado. Os rendimentos foram calculados a partir da massa obtida na extração e da umidade do material vegetal. A análise qualitativa foi realizada por cromatografia em fase gasosa acoplada à espectrometria de massas e a avaliação dos teores dos constituintes químicos por cromatografia em fase gasosa com detector de ionização de chamas. O efeito bacteriostático de diferentes concentrações dos óleos essenciais, puros e em combinação, foi determinado pela técnica de difusão em ágar. As concentrações mínimas inibitórias (CMIs) foram utilizadas na determinação do tempo de ação bactericida. O rendimento, em base seca, foi de 1,39 por cento (v/p) para o óleo essencial de C. citratus e de 2,27 por cento (v/p) para o óleo essencial de C. nardus. Geranial e neral foram os constituintes majoritários do óleo essencial de C. citratus, enquanto, para C. nardus, foram citronelal, geraniol e citronelol. A maioria das concentrações utilizadas mostrou-se efetiva contra Listeria monocytogenes e observaram-se efeitos bactericidas nas CMIs. Óleos essenciais de C. citratus e C. nardus, puros e em combinação, constituem novas alternativas de antibacterianos naturais a serem utilizados no controle de L. monocytogenes na indústria de alimentos.

Resultados: N/A

Conclusão: N/A

Efeito inibitório de óleos essenciais sobre microrganismos do canal radicular/ Inhibitory effect of essential oils against organisms from root canal

Autores: Cavalcanti, Yuri Wanderley; Pérez, Ana Luíza Alves de Lima; Xavier, Gabriela Dantas Rocha; Almeida, Leopoldina de Fátima Dantas de | Ano: 2011 | Database: LILACS

Resumo: Introdução: os óleos essenciais apresentam propriedades biológicas, as quais devem ser estudadas de modo a investigar novas possibilidades de constituição de soluções irrigadoras. Objetivo: avaliar o efeito inibitóriode óleos essenciais extraídos de plantas sobre a atividade de microrganismos envolvidos na infecção do canal radicular. Material e método: foram selecionados os óleos essenciais de Melaleuca alternifolia (melaleuca), Cymbopogon winterianus (citronela), Thymus vulgaris (tomilho), Ocimum basilicum (manjericão), Cymbopogon martinii (palmarosa) e Cinnamomum cassia (canela-da-china). A atividade antimicrobiana sobre Candida albicans (ATCC 289065) e Enterococcus faecalis (ATCC 29212) foi avaliada por meio da triagem da atividade antimicrobiana e da determinação da Concentração Inibitória Mínima (CIM). As soluções de Digluconato de Clorexidina (0,12%) e Hipoclorito de Sódio (1%) serviram de controle. Resultado: os halos de inibição docrescimento para E. faecalis variaram entre 8,00 e 26,00 mm, enquanto que a variação para C. albicans foi entre 26,67 e > 35,00 mm. Os óleos essenciais de T. vulgaris, C. martinii e C. cassia apresentaram CIM na concentração 0,56 mg.mL­1 frente às cepas testadas. Menor atividade foi demonstrada por O. basilicum, que apresentou CIM nas concentrações 72,00 e 1,12 mg.mL­1 contra E. faecalis e C. albicans, respectivamente. Conclusão: os produtos testados apresentaram efeito inibitório satisfatório sobre E. faecalis e C. albicans, destacando-se os óleos essenciais de T. vulgaris, C. martinii e C. cassia.

Resultados: N/A

Conclusão: N/A

Atividade antimicrobiana de óleos essenciais e compostos isolados frente aos agentes patogênicos de origem clínica e alimentar/ Antimicrobial activity of the essential oils and isolated compounds on the hospital-borne and foodborne pathogens

Autores: Santos, Caio Henrique da Silva; Piccoli, Roberta Hilsdorf; Tebaldi, Victor Maximiliano Reis | Ano: 2017 | Database: LILACS

Resumo: Os óleos essenciais de plantas demonstram atividade antimicrobiana frente a diversos micro-organismos, e são considerados como alternativa ao uso de antibióticos convencionais. Este estudo testou a eficácia de óleos essenciais de canela (Cinnamomum cassia), orégano (Origanum vulgare), cravo-da-índia (Syzygium aromaticum), citronela (Cymbopogon nardus), além dos compostos isolados citral contra Staphylococcus aureus ATCC 25923 e citral e carvacrol contra Pseudomonas aeruginosa. Empregou-se o método de microdiluição em Caldo Tripticaseina de Soja (TSB) em placa de 96 cavidades para determinar a Concentração Inibitória Mínima (CIM) e posterior semeadura em Ágar Tripticaseina de Soja (TSA) para definir a Concentração Bactericida Mínima (CBM). Os inóculos foram padronizados (107 UFC/mL) de acordo com a escala de MacFarland. Os óleos essenciais de canela, orégano e citronela mostraram atividade antimicrobiana contra os dois microrganismos em diferentes concentrações. O óleo essencial de cravo-da-índia não apresentou efeitos inibitórios nas concentrações testadas. O carvacrol inibiu P. aeruginosa a partir da concentração 1,25 %. O citral inibiu S. aureus a partir da concentração 0,03 %, porém não apresentou atividade contra P. aeruginosa. O óleo essencial de citronela e o composto citral foram mais eficazes contra S. aureus. Para P. aeruginosa, o óleo essencial de canela apresentou atividade antimicrobiana nas menores concentrações.

Resultados: N/A

Conclusão: N/A

Identification of essential oils with activity against stationary phase Staphylococcus aureus.

Autores: Shuzhen Xiao, Peng Cui, Wanliang Shi, Ying Zhang | Ano: 2020 | Database: pubmed

Resumo: Staphylococcus aureus is the most dominant human pathogen, responsible for a variety of chronic and severe infections. There is mounting evidence that persisters are associated with treatment failure and relapse of persistent infections. While some essential oils were reported to have antimicrobial activity against growing S. aureus, activity of essential oils against the stationary phase S. aureus enriched in persisters has not been investigated.

Resultados: We identified 39 essential oils (Oregano, Cinnamon bark, Thyme white, Bandit "Thieves", Lemongrass (Cymbopogon flexuosus), Sandalwood oil, Health shield, Allspice, Amyris, Palmarosa, Cinnamon leaf, Clove bud, Citronella, Geranium bourbon, Marjoram, Peppermint, Lemongrass, Cornmint, Elemi, Ho wood, Head ease, Lemon eucalyptus, Litsea cubeba, Myrrh, Parsley seed, Coriander oil, Dillweed, Hyssop, Neroli, Rosewood oil, Tea tree, Cajeput, Clove bud, Lavender, Sleep tight, Vetiver, Palo santo, Sage oil, Yarrow) at 0.5% (v/v) concentration, 10 essential oils (Cinnamon bark, Oregano, Thyme white, Bandit "Thieves", Lemongrass, Sandalwood oil, Health shield, Allspice, Amyris, Palmarosa at 0.25% (v/v) concentration, and 7 essential oils (Oregano, Cinnamon bark, Thyme white, Lemongrass, Allspice, Amyris, Palmarosa at 0.125% (v/v) concentration to have high activity against stationary phase S. aureus with no visible growth on agar plates after five-day exposure. Among the 10 essential oils which showed high activity at 0.25% (v/v) concentration, 9 (Oregano, Cinnamon bark, Thyme white, Bandit "Thieves", Lemongrass, Health shield, Allspice, Palmarosa, Amyris showed higher activity than the known persister drug tosufloxacin, while Sandalwood oil had activity at a higher concentration. In Oregano essential oil combination studies with antibiotics, Oregano plus tosufloxacin (or levofloxacin, ciprofloxacin) and rifampin completely eradicated stationary phase S. aureus cells, but had no apparent enhancement for linezolid, vancomycin, sulfamethoxazole, trimethoprim, azithromycin or gentamicin.

Conclusão: N/A

Identification of essential oils with activity against stationary phase Staphylococcus aureus.

Autores: Shuzhen Xiao, Peng Cui, Wanliang Shi, Ying Zhang | Ano: 2020 | Database: pubmed

Resumo: Staphylococcus aureus is the most dominant human pathogen, responsible for a variety of chronic and severe infections. There is mounting evidence that persisters are associated with treatment failure and relapse of persistent infections. While some essential oils were reported to have antimicrobial activity against growing S. aureus, activity of essential oils against the stationary phase S. aureus enriched in persisters has not been investigated.

Resultados: We identified 39 essential oils (Oregano, Cinnamon bark, Thyme white, Bandit "Thieves", Lemongrass (Cymbopogon flexuosus), Sandalwood oil, Health shield, Allspice, Amyris, Palmarosa, Cinnamon leaf, Clove bud, Citronella, Geranium bourbon, Marjoram, Peppermint, Lemongrass, Cornmint, Elemi, Ho wood, Head ease, Lemon eucalyptus, Litsea cubeba, Myrrh, Parsley seed, Coriander oil, Dillweed, Hyssop, Neroli, Rosewood oil, Tea tree, Cajeput, Clove bud, Lavender, Sleep tight, Vetiver, Palo santo, Sage oil, Yarrow) at 0.5% (v/v) concentration, 10 essential oils (Cinnamon bark, Oregano, Thyme white, Bandit "Thieves", Lemongrass, Sandalwood oil, Health shield, Allspice, Amyris, Palmarosa at 0.25% (v/v) concentration, and 7 essential oils (Oregano, Cinnamon bark, Thyme white, Lemongrass, Allspice, Amyris, Palmarosa at 0.125% (v/v) concentration to have high activity against stationary phase S. aureus with no visible growth on agar plates after five-day exposure. Among the 10 essential oils which showed high activity at 0.25% (v/v) concentration, 9 (Oregano, Cinnamon bark, Thyme white, Bandit "Thieves", Lemongrass, Health shield, Allspice, Palmarosa, Amyris showed higher activity than the known persister drug tosufloxacin, while Sandalwood oil had activity at a higher concentration. In Oregano essential oil combination studies with antibiotics, Oregano plus tosufloxacin (or levofloxacin, ciprofloxacin) and rifampin completely eradicated stationary phase S. aureus cells, but had no apparent enhancement for linezolid, vancomycin, sulfamethoxazole, trimethoprim, azithromycin or gentamicin.

Conclusão: N/A

Atividade fungicida do óleo essencial de Cymbopogon winterianus jowit (Citronela) contra Fusarium solani/ Fungicide activity of essential oil Cymbopogon winterianus jowit (Citronella) against Fusarium solani

Autores: Cruz, Tatiane Paulino da; Alves, Fábio Ramos; Mendonça, Rodolfo Ferreira; Costa, Adilson Vidal; Jesus Junior, Waldir Citra de; Pinheiro, Patrícia Fontes; Marins, André Kulitz | Ano: 2015 | Database: LILACS

Resumo: O declínio é a principal doença da goiabeira causada pelo parasitismo de Meloidogyne enterolobii e pelo fungo Fusarium solani, tem sido responsável pela erradicação de muitos pomares em âmbito nacional, o que resulta em elevada perda econômica aos produtores. Devido à crescente pressão da sociedade por produtos naturais e com o aumento da importância dos óleos essenciais no manejo de doenças de plantas, o objetivo deste trabalho foi identificar os principais componentes e avaliar o efeito fungitóxico do óleo essencial de Cymbopogon winterianus (citronela) sobre três isolados de Fusarium solani (UENF/CF163, UENF/CF241 e UENF/CF295). O óleo essencial foi obtido por hidrodestilação, utilizando o aparelho tipo Clevenger. Os compostos foram identificados por cromatografia gasosa e cromatografia gasosa com detector de massas do óleo essencial. Para avaliar o efeito dos óleos essenciais no crescimento micelial, esporulação e germinação de esporos do fungo, foram utilizadas alíquotas de 5, 10, 15, 20, 25 e 30 µL do óleo essencial que foram distribuídas na superfície do meio de cultura BDA contido em placas de Petri antes da repicagem do fungo. O delineamento experimental foi inteiramente casualizado num esquema fatorial 1 x 6 + 1, (um óleo, seis alíquotas e uma testemunha adicional), com 5 repetições. Os principais componentes encontrados no óleo de C. winterianus foram o geranial (28,62%), citronelol (23,62%) e neral (17,10%). A menor alíquota do óleo essencial de citronela (5µL) inibiu em mais de 90% a germinação de esporos dos isolados UENF/CF241 e UENF/CF295 e reduziu a produção de esporos em mais de 95% nos três isolados, indicando que esse óleo possui uma boa atividade fungitoxica para esses isolados.

Resultados: N/A

Conclusão: N/A

Toxicity and larvicidal activity on Aedes aegypti of citronella essential oil submitted to enzymatic esterification.

Autores: R L Cansian, A Staudt, J L Bernardi, B M S Puton, D Oliveira, J V de Oliveira, A C C Gomes, B C O P Andrade, I C R Leal, N K Simas, J Zeni, A Jungues, R M Dallago, G T Backes, N Paroul | Ano: 2021 | Database: pubmed

Resumo: The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-1 were obtained for the essential oil and 4.36 μg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-1 for the essential oil of citronella and 86.30 μg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.

Resultados: N/A

Conclusão: N/A

Induced variations by gamma radiation and EMS on the agronomic traits, essential oil yield with its quality and their exploitation in Java citronella (Cymbopogon winterianus Jowitt).

Autores: Sunita Munda, Twahira Begum, Ankita Gogoi, Sudin Kr Pandey, Neelav Sarma, Mohan Lal | Ano: 2022 | Database: pubmed

Resumo: The slips of Cymbopogon winterianus (Java citronella) are used to propagate this industrially important crop. It does not have a mating system that allows it to create new variability or develop superior progenies, which could be addressed by using induced mutation caused by physical or chemical agents. Physical treatments, rather than chemical treatments, are believed to be the most incredible alternative for mutation breeding. As a result, this study aims to assess the effects of gamma radiation and EMS treatment on the development of better C. winterianus progenies.

Resultados: The morpho-chemical study of the 112 healthy mutants has led to the identification of six superior progenies in MV4 progenies, M17, M63, M77, M179, M233, and M392. In terms of the economic yield, it was observed that mutant M77 treated with 0.20% EMS dose increased the herbage yield and citronellal content tremendously. In contrast, the progeny M17 irradiated with γ-100Gy increased essential oil yield from 1.32% to 1.50%. The EMS treatment at 0.10% and 0.20% doses showed an increasing trend in plant height, leaf length, tillers/bush, leaves/bush, herbage yield, and citronellal content compared to the base variety. The LD50 value of C. winterianus for gamma radiation and EMS treatment was averaged at 173 Gy and 0.72%, respectively.

Conclusão: In C. winterianus, both gamma rays and EMS treatment successfully created superior progenies with desired characteristics. The 0.20 percent EMS treatment significantly improved economic features, including herbage yield and citronellal content. Simultaneously, gamma radiation at 100 Gy produced the highest essential oil yield, which is a highly desirable characteristic in C. winterianus breeding.

Effects of essential oils on native and recombinant acetylcholinesterases of Rhipicephalus microplus.

Autores: Everton Gomes Guimarães Dos Santos, Wallyson André Dos Santos Bezerra, Kevin B Temeyer, Adalberto A Pérez de León, Livio Martins Costa-Junior, Alexandra Martins Dos Santos Soares | Ano: 2021 | Database: pubmed

Resumo: This study reports the action of essential oils (EO) from five plants on the activity of native and recombinant acetylcholinesterases (AChE) from Rhipicephalus microplus. Enzyme activity of native susceptible AChE extract (S.AChE), native resistant AChE extract (R.AChE), and recombinant enzyme (rBmAChE1) was determined. An acetylcholinesterase inhibition test was used to verify the effect of the EO on enzyme activity. EO from Eucalyptus globulus, Citrus aurantifolia, Citrus aurantium var.dulcis inhibited the activity of S.AChE and R.AChE. Oils from the two Citrus species inhibited S.AChE and R.AChE in a similar way while showing greater inhibition on R.AChE. The oil from E. globulus inhibited native AChE, but no difference was observed between the S.AChE and R.AChE; however, 71% inhibition for the rBmAChE1 was recorded. Mentha piperita oil also inhibited S.AChE and R.AChE, but there was significant inhibition at the highest concentration tested. Cymbopogon winterianus oil did not inhibit AChE. Further studies are warranted with the oils from the two Citrus species that inhibited R.AChE because of the problem with R. microplus resistant to organophosphates, which target AChE. C. winterianus oil can be used against R. microplus populations that are resistant to organophosphates because its acaricidal properties act by mechanism(s) other than AChE inhibition.

Resultados: N/A

Conclusão: N/A

Toxicity and larvicidal activity on Aedes aegypti of citronella essential oil submitted to enzymatic esterification/ Toxicidade e atividade larvicida sobre Aedes aegypti de óleo essencial de citronella submetido à esterificação enzimática

Autores: Cansian, R L; Staudt, A; Bernardi, J L; Puton, B M S; Oliveira, D; de Oliveira, J V; Gomes, A C C; Andrade, B C O P; Leal, I C R; Simas, N K; Zeni, J; Jungues, A; Dallago, R M; Backes, G T; Paroul, N | Ano: 2023 | Database: LILACS

Resumo: Abstract The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-1 were obtained for the essential oil and 4.36 μg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-1 for the essential oil of citronella and 86.30 μg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.

Resultados: N/A

Conclusão: N/A

The effects of plant essential oils on escape response and mortality rate of Aedes aegypti and Anopheles minimus.

Autores: Sunaiyana Sathantriphop, Nicole L Achee, Unchalee Sanguanpong, Theeraphap Chareonviriyaphap | Ano: 2015 | Database: pubmed

Resumo: The High Throughput Screening System (HITSS) has been applied in insecticide behavioral response studies with various mosquito species. In general, chemical or natural compounds can produce a range of insect responses: contact irritancy, spatial repellency, knock-down, and toxicity. This study characterized these actions in essential oils derived from citronella, hairy basil, catnip, and vetiver in comparison to DEET and picaridin against Aedes aegypti and Anopheles minimus mosquito populations. Results indicated the two mosquito species exhibited significantly different (P<0.05) contact irritant escape responses between treatment and control for all tested compound concentrations, except with the minimum dose of picaridin (P>0.05) against Ae. aegypti. Spatial repellency responses were elicited in both mosquito species when exposed to all compounds, but the strength of the repellent response was dependent on compound and concentration. Data show that higher test concentrations had greatest toxic effects on both mosquito populations, but vetiver had no toxic effect on Ae. aegypti and picaridin did not elicit toxicity in either Ae. aegypti or An. minimus at any test concentration. Ultimately, this study demonstrates the ability of the HITSS assay to guide selection of effective plant essential oils for repelling, irritating, and killing mosquitoes.

Resultados: N/A

Conclusão: N/A

Authenticity control of essential oils containing citronellal and citral by chiral and stable-isotope gas-chromatographic analysis.

Autores: Tran-Thi Nhu-Trang, Hervé Casabianca, Marie-Florence Grenier-Loustalot | Ano: 2006 | Database: pubmed

Resumo: Enantioselective capillary GC on a Supelco beta-DEX 225 column (heptakis(2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-beta-cyclodextrin SPB 20poly--20% diphenyl, 80% dimethylsiloxane) and isotope-ratio mass spectrometry, coupled online with capillary GC on an HP5 column have been used for origin-specific analysis and authenticity control of essential oils, for example lemon (Citrus limon), lemongrass (Cymbopogon citratus and Cymbopogon flexuosus), citronella (Cymbopogon nardus L.--Ceylon type and Cymbopogon winterianus--Java type), Litsea cubeba, Lippia citriodora, lemon myrtle (Backhousia citriodora), lemon gum (Eucalyptus citriodora), and, especially, precious lemon balm oil (Melissa officinalis L.). Isotope data (delta13C(PDB) and delta2H(V-SMOW)) for citral (neral + geranial) and citronellal from on-line GC-C/Py-IRMS and chiral data for citronellal in these essential oils are reported. The possibility of using these data to determine the origin of these essential oils and to detect adulteration is discussed. Principal-components analysis (PCA) of specific compounds in two essential oils of lemongrass and Litsea cubeba was performed as a practical statistical method for distinguishing between these two types of oil.

Resultados: N/A

Conclusão: N/A

Controle fitopatológico do Fusarium subglutinans pelo óleo essencial do capim-citronela (Cymbopogon nardus L. ) e do composto citronelal/ Fungitoxic activity of essential oil of citronella grass (Cymbopogon nardus L. ) and compound citronellal

Autores: Seixas, P. T. L; Castro, H. C; Santos, G. R; Cardoso, D. P | Ano: 2011 | Database: LILACS

Resumo: Este trabalho teve como objetivo avaliar o efeito fungitóxico do óleo essencial de capim-citronela e do seu constituinte majoritário citronelal sobre a inibição micelial do fitopatógeno Fusarium subglutinans, agente causal da fusariose da cultura do abacaxi (Ananas comosus). Para avaliar o efeito do óleo essencial no crescimento micelial do fungo, foram utilizadas seis alíquotas (0, 5, 10, 15, 20 e 25 ìL) do óleo e do citronelal que foram distribuídas na superfície do meio BDA (batata-dextrose-ágar) antes da repicagem do fungo. O crescimento micelial foi medido após 48 h de instalação do experimento e em cinco épocas de avaliação (2, 4, 6, 8 e 10 dias após repicagem). Os resultados indicaram que o óleo essencial do capim-citronela demonstrou maior efeito inibitório do crescimento micelial do fungo F. subglutinans do que o composto citronelal. Em todas as alíquotas utilizadas o óleo essencial proporcionou menor taxa de crescimento micelial do que o citronelal.

Resultados: N/A

Conclusão: N/A

Design, development and assessment of an essential oil based slow release vaporizer against mosquitoes.

Autores: Hemanga Hazarika, Varun Tyagi, Harshita Krishnatreyya, Probin K Roy, Johirul Islam, Sourav Chakraborty, Neelutpal Gogoi, Sumit Kishor, Yangchen D Bhutia, Danswrang Goyary, Sanjeev Karmakar, Sanjai K Dwivedi, Kamaruz Zaman, Pronobesh Chattopadhyay | Ano: 2020 | Database: pubmed

Resumo: Mosquitoes (Diptera; Culicidae) are a biting nuisance and are of economic and health importance, especially for people living in tropical countries like India. Given the environmental concerns and health hazards of synthetic insecticides, development of natural products for the control of mosquito and mosquito-borne diseases are needed. In view of this, an essential oil based novel liquid vaporizer formulation with citronella and eucalyptus oils has been developed using a computer aided Artificial Neural Network and Particle Swarm Optimization (ANN-PSO) algorithm approach, aiming to predict the best optimized formulation (OF). Following the development, OF was characterized by Fourier Transform-Infra Red (FT-IR) spectroscopy and gas chromatography-mass spectroscopy (GC-MS). The efficacy of the OF was assessed against two major mosquito vectors viz. Anopheles stephensi and Aedes albopictus using a Peet-Grady chamber. Finally, toxicological impacts of the OF following its inhalation were investigated as per the Organization for Economic Co-operation and Development (OECD) guidelines. The results revealed all the ideal characteristics of the OF which were found to provide a slow release of up to 450 h at room temperature. Most importantly, the OF, exhibited 50% mosquito knock down (KT50) within 11.49±1.34 and 14.15±2.15 min against An. stephensi and Ae. albopictus respectively. Toxicity assessment showed a non toxic nature of the OF following inhalation. Thus the present development would be beneficial for controlling both An. stephensi and Ae. albopictus without any associated health hazards.

Resultados: N/A

Conclusão: N/A

Efeito da adubação orgânica na produção de biomassa e bioatividade do óleo essencial do capim citronela/ Effect of organic fertilization on biomass production and bioactivity of citronella grass essential oil

Autores: De Aguiar Soares, Adriano; De Guilhon Castro, Henrique; Dos Santos, Gil Rodrigues; Cardoso, Dione Pereira; Chagas Júnior, Aloisio Freitas; De Souza Aguiar, Raimundo Wagner | Ano: 2014 | Database: LILACS

Resumo: RESUMO Este trabalho teve como objetivo analisar o efeito da adubação orgânica no crescimento e na produção de biomassa do capim citronela (Cymbopogon nardus), assim como avaliar o efeito do óleo essencial do capim citronela e do composto citronelal na inibição do crescimento micelial do fungo Didymella bryoniae. Na avaliação do efeito da adubação orgânica no crescimento do capim citronela, foi utilizado o delineamento em blocos casualizados em esquema de parcela subdividida. As parcelas foram constituídas por quatro doses de adubação orgânica de esterco bovino curtido (0, 3, 6 e 9 Kg cova-1) e as subparcelas por cinco épocas de amostragem (80, 108, 136, 164, 192 dias após o transplante). Para avaliar a fungitoxicidade do óleo essencial do capim citronela na inibição do crescimento micelial do fungo D. bryoniae, foi instalado no delineamento inteiramente casualizado em esquema fatorial. Os tratamentos foram compostos por cinco alíquotas (5, 10, 15, 20 e 25 µL) do óleo essencial do capim citronela e do composto citronelal, em cinco épocas de amostragem. Verificou-se no tratamento de adubação orgânica de 9 Kg cova-1 os maiores valores em todas as variáveis analisadas na última época de amostragem. Constatou-se maior efeito de inibição do crescimento micelial utilizando o citronelal em comparação com o óleo essencial. Na alíquota de 25 µL do citronelal ocorreu inibição total do crescimento micelial do fungo D. bryoniae.

Resultados: N/A

Conclusão: N/A

Avaliação in vitro de diferentes métodos de análises de fungitoxicidade de óleos essenciais/ Evaluation in vitro of different methods of analysis fungitoxicity of essential oils

Autores: Sarmento-Brum, Rúbia Borges Cruz; Santos, Gil Rodrigues dos; Castro, Henrique Guilhon de; Gonçalves, Clebson Gomes; Cardon, Carlos Henrique; Leão, Evelynne Urzêdo; Sarmento, Renato de Almeida | Ano: 2013 | Database: LILACS

Resumo: Os problemas ambientais causados por fungicidas sintéticos têm elevado as buscas por métodos alternativos de controle de doenças de plantas. Objetivou-se avaliar o efeito do óleo essencial de capim citronela, sobre o fungo Rhizoctonia solani, em diferentes métodos de avaliação de fungitoxicidade in vitro. Foi utilizado delineamento inteiramente casualizado em esquema fatorial com quatro repetições, onde os fatores foram compostos por quatro métodos de avaliação da fungitoxicidade in vitro do óleo essencial (óleo essencial diluído em Tween 80 (0,5%) e incorporado ao meio de cultura BDA (batata, dextrose e ágar) ainda fundente; óleo essencial diluído em Tween 80 (0,5%) e distribuído na superfície do BDA; óleo essencial diluído em Tween 80 (0,5%) e distribuído em papel filtro fixado na superfície interna da tampa da placa de Petri; óleo essencial puro e distribuído na superfície do meio de cultura; e testemunha) e por cinco épocas de avaliação (2, 4, 6, 8 e 10 dias de incubação). Foram utilizados 0,25µL mL-1 do óleo do capim citronela em todos os tratamentos. Dos tratamentos avaliados o uso do óleo puro distribuído na superfície do meio de cultura foi mais eficiente na redução do diâmetro micelial em todas as avaliações. Neste método a taxa de crescimento micelial foi de 9, 02 mm dia-1, atingindo na última época de avaliação 79,77 mm.

Resultados: N/A

Conclusão: N/A

Avaliação in vitro de diferentes métodos de análises de fungitoxicidade de óleos essenciais/ Evaluation in vitro of different methods of analysis fungitoxicity of essential oils

Autores: Sarmento-Brum, Rúbia Borges Cruz; Santos, Gil Rodrigues dos; Castro, Henrique Guilhon de; Gonçalves, Clebson Gomes; Cardon, Carlos Henrique; Leão, Evelynne Urzêdo; Sarmento, Renato de Almeida | Ano: 2013 | Database: LILACS

Resumo: Os problemas ambientais causados por fungicidas sintéticos têm elevado as buscas por métodos alternativos de controle de doenças de plantas. Objetivou-se avaliar o efeito do óleo essencial de capim citronela, sobre o fungo Rhizoctonia solani, em diferentes métodos de avaliação de fungitoxicidade in vitro. Foi utilizado delineamento inteiramente casualizado em esquema fatorial com quatro repetições, onde os fatores foram compostos por quatro métodos de avaliação da fungitoxicidade in vitro do óleo essencial (óleo essencial diluído em Tween 80 (0,5%) e incorporado ao meio de cultura BDA (batata, dextrose e ágar) ainda fundente; óleo essencial diluído em Tween 80 (0,5%) e distribuído na superfície do BDA; óleo essencial diluído em Tween 80 (0,5%) e distribuído em papel filtro fixado na superfície interna da tampa da placa de Petri; óleo essencial puro e distribuído na superfície do meio de cultura; e testemunha) e por cinco épocas de avaliação (2, 4, 6, 8 e 10 dias de incubação). Foram utilizados 0,25µL mL-1 do óleo do capim citronela em todos os tratamentos. Dos tratamentos avaliados o uso do óleo puro distribuído na superfície do meio de cultura foi mais eficiente na redução do diâmetro micelial em todas as avaliações. Neste método a taxa de crescimento micelial foi de 9, 02 mm dia-1, atingindo na última época de avaliação 79,77 mm.

Resultados: N/A

Conclusão: N/A

Formulation process, physical stability and herbicidal activities of Cymbopogon nardus essential oil-based nanoemulsion.

Autores: Naphat Somala, Chamroon Laosinwattana, Montinee Teerarak | Ano: 2022 | Database: pubmed

Resumo: Essential oil-based bioherbicides are a promising avenue for the development of eco-friendly pesticides. This study formulated nanoemulsions containing citronella (Cymbopogon nardus) essential oil (CEO) as an herbicidal product using a high-pressure homogenization method with hydrophilic-lipophilic balance (HLB) values ranging 9-14.9 for the surfactant mixture (Tween 60 and Span 60). The CEO was high in monoterpene compounds (36.333% geraniol, 17.881% trans-citral, 15.276% cis-citral, 8.991% citronellal, and 4.991% β-citronellol). The nanoemulsion at HLB 14 was selected as optimal due to having the smallest particle size (79 nm, PI 0.286), confirmed by transmission electron microscopy. After 28 days of storage, particle size in the selected formulation changed to 58 and 140 nm under 4 °C and 25 °C, respectively. Germination and seedling growth assays with Echinochloa crus-galli showed that the nanoemulsion exerted a significant dose-dependent inhibitory effect at all tested HLBs (9-14.9) and concentrations (100-800 µL/L). The inhibitory effect was greatest at HLB 14. Treatment of E. cruss-galli seed with the HLB 14 nanoemulsion significantly reduced seed imbibition and α-amylase activity. Our findings support that CEO nanoemulsions have a phytotoxic effect and hence herbicidal properties for controlling E. cruss-galli. Accordingly, this nanoemulsion may have potential as a bioherbicide resource.

Resultados: N/A

Conclusão: N/A

In vitro evaluation of the resistence of the Contracaecum sp. larvae (Railliet & Henry, 1912) (Nematoda: Anisakidae), to the essential oil of citronella ( Cymbopogon sp.) (Poaceae)

Autores: Justino, Christiano Henrique da Silva; Barros, Luciano Antunes | Ano: 2008 | Database: LILACS

Resumo: The essential oil of citronella ( Cymbopogon sp.) was used in vitro to assess its influence on the L3 larvae of Contracaecum sp. The parameters investigated were the morphological integrity and motility of the larvae after being in contact with the product. The essential oil was very effective in its trade form killing all the larvae at the utmost in two hours. The damage caused to the larvae was evaluated with a microscope in histological cuts, where cuticular rupture and disintegration of the intestinal wall of the larvae were found. The results were analyzed through the use of a monocaudal Fisher test to detect differences between the groups where the significance of p<0,05 was obtained.

Resultados: N/A

Conclusão: N/A

Insecticidal Properties of Ocimum basilicum and Cymbopogon winterianus against Acanthoscelides obtectus, Insect Pest of the Common Bean (Phaseolus vulgaris, L.).

Autores: Álvaro Rodríguez-González, Samuel Álvarez-García, Óscar González-López, Franceli Da Silva, Pedro A Casquero | Ano: 2019 | Database: pubmed

Resumo: The bean weevil, Acanthoscelides obtectus Say (Coleoptera: Chrysomelidae: Bruchinae), causes severe post-harvest losses in the common bean, Phaseolus vulgaris L. The control of this insect is still poor and involves the use of conventional insecticides. There is an increasing demand in the search for new active substances and products for pest control towards reduction of adverse effects on human health and the environment. The protection of grains with alternative products, such as essential oils, is a possible alternative to meet the needs described above. Therefore, this investigation evaluated the applications of basil, Ocimum basilicum, and citronella, Cymbopogon winterianus, essential oils for A. obtectus control. These essential oils significantly reduced the bean weight losses and the number of beans damaged by A. obtectus at higher doses than 60 or 120 μL/sample. The number of holes per bean did not differ between the doses of basil essential oil, not even at the dose of 60 μL, while it was higher at 120 μL, probably due to a lower capacity of movement of the insects treated with this dose and/or the oil's direct or indirect effects on the insects. Basil and citronella oils exhibited similar patterns of insecticidal activity over the insect, both directly in adult insects or indirectly over bean seeds. These essential oils affected the development of A. obtectus since the greatest doses applied on beans decreased the emergence of the bean weevil. The results prove the insecticidal capacity of the tested essential oils and hence their potential as active substances against A. obtectus in environmentally low risk pest control strategies. Supplementary trials should be conducted under real storage conditions.

Resultados: N/A

Conclusão: N/A

Nanobiopesticides: development and inseticidal activity of nanoemulsions containing lemongrass or eucalyptus oils.

Autores: Maiara Callegaro Velho, Luciana Filippin Cossetin, Samantha Nunes de Godoi, Roberto Christ Vianna Santos, André Gündel, Silvia Gonzalez Monteiro, Aline Ferreira Ourique | Ano: 2021 | Database: pubmed

Resumo: The bioinsecticides, like essential oils, are a promising alternative in pest control. However, these oils have some limitations, such as instability and low solubility. These limitations can be circumvented through nanotechnology, with the nanoemulsification of these compounds. Therefore, the objective of this study was to prepare, characterize and explore the insecticidal activity against adult flies of nanoemulsions containing essential oil of lemongrass or eucalyptus. The nanoemulsions were prepared by the high-energy method and presented droplet size smaller than 125 nm, with polydispersity index of 0.2, pH acid and spherical morphology. The insecticidal activity was evaluated by the Topical Application Method and Exposure Impregnated Paper Exposure, where it was possible to demonstrate a potential insecticidal effect of lemongrass oil in the concentrations of 10, 30 and 50 µL/mL against Musca domestica and Lucilia cuprina and the potentiation of this effect when nanoemulsified this oil against L. cuprina.

Resultados: N/A

Conclusão: N/A

Efeito moluscicida do óleo essencial de Cymbopogon winterianus Jowitt (Poaceae) sobre Lymnaea columella (Say, 1817) e Biomphalaria tenagophila (D'Orbigny, 1835)/ Molluscicidal effect of essential oil of Cymbopogon winterianus Jowitt (Poaceae) on Lymnaea columella (Say, 1817) and Biomphalaria tenagophila (D'Orbigny, 1835)

Autores: COSTA, A.V.; ALMEIDA, B.R.; GONÇALVES, L.V.; CRICO, K.B.; IGNACCHITI, M.D.C.; PEREIRA JUNIOR, O.S.; PINHEIRO, P.F.; QUEIROZ, V.T. | Ano: 2015 | Database: LILACS

Resumo: RESUMO O uso das substâncias moluscicidas convencionais no controle de planorbídeos vetores constitui-se uma importante ferramenta no combate da fasciolose hepática e esquistossomose. Sendo, portanto, de extrema relevância para a pecuária e para os serviços de Vigilância Epidemiológica. Por outro lado, a seleção de caramujos resistentes a tais substâncias e sua baixa seletividade estimulam a busca por novas substâncias. Neste sentido, o presente trabalho foi desenvolvido para avaliar o efeito do óleo essencial de Cymbopogon winterianusJowitt sobre Lymnaea columella e Biomphalaria tenagophila, hospedeiros intermediários de Fasciola hepatica e esquistossomose mansônica, respectivamente. O óleo essencial foi extraído a partir de folhas frescas utilizando o sistema Clevenger. A análise qualitativa foi realizada por meio de cromatografia gasosa acoplada a espectrometria de massas (CG/EM) e a quantificação dos constituintes presentes no óleo foi determinada por cromatografia gasosa acoplada ao detector de ionização de chama (CG/DIC). O efeito moluscicida foi avaliado utilizando seis moluscos de cada espécie e o óleo essencial de C. winterianus nas concentrações finais de 10, 20, 30, 40, 60, 80 e 100 ppm. A análise por cromatografia gasosa do óleo essencial possibilitou a identificação dos componentes majoritários geraniol (28,62%), citronelal (23,62%) e citronelol (17,10%). Os valores de DL100 e DL50para os moluscos das espécies L. columella e B. tenagophila foram, respectivamente, 60 e 40 ppm; 80 ppm e 60 ppm. O óleo de Cymbopogon winterianus demonstrou-se uma alternativa promissora para o controle dos moluscos, sendo a espécie L. columella mais sensível ao mesmo.

Resultados: N/A

Conclusão: N/A

[Peculicidal activity of plant essential oils and their based preparations].

Autores: Iu V Lopatina, O Iu Eremina | Ano: 2014 | Database: pubmed

Resumo: The peculicidal activity of eight plant essential oils in 75% isopropyl alcohol was in vitro investigated. Of them, the substances that were most active against lice were tea tree (Melaleuca), eucalyptus, neem, citronella (Cymbopogon nardus), and clove (Syzygium aromaticum) oils; KT50 was not more than 3 minutes on average; KT95 was 4 minutes. After evaporating the solvent, only five (tea tree, cassia, clove, anise (Anisum vulgare), and Japanese star anise (Illicium anisatum) oils) of the eight test botanical substances were active against lice. At the same time, KT50 and KT95 showed 1.5-5-fold increases. Citronella and anise oils had incomplete ovicidal activity. Since the lice were permethrin-resistant, the efficacy of preparations based on essential oils was much higher than permethrin.

Resultados: N/A

Conclusão: N/A

Investigation of the dermal sensitization potential of various essential oils in the local lymph node assay.

Autores: J Lalko, A M Api | Ano: 2006 | Database: pubmed

Resumo: Essential oils are commonly used fragrance ingredients. The oils themselves are complex mixtures, which may contain naturally occurring contact sensitizers. The local lymph node assay was used to evaluate the dermal sensitization potential of basil, citronella, clove leaf, geranium, litsea cubeba, lemongrass, and palmarosa oils. Three of the major components--citral, eugenol, and geraniol--were included to investigate any difference in sensitization potential arising from their exposure in a mixture. Each fragrance material was tested at five concentration ranging from 2.5% to 50% w/v in 1:3 ethanol:diethyl phthalate. The stimulation index (SI) values were calculated for each dose level, an SI > or = 3 was considered a positive response. The estimated concentration (EC3) required to elicit a positive was calculated and taken as a measure of relative potency. The EC3 values and potency classification for basil, clove leaf, litsea cubeba, lemongrass and palmarosa oils were calculated to be <2.5% (> or = moderate), 7.1% (weak), 8.4% (weak), 6.5% (weak) and 9.6% (weak), respectively. Citronella and geranium oils were negative. The individual components citral, eugenol and geraniol resulted in EC3 values of 6.3%, 5.4% and 11.4%, respectively. In general, the potency of each essential oil did not differ significantly from that observed for its main individual component.

Resultados: N/A

Conclusão: N/A

Investigation of the dermal sensitization potential of various essential oils in the local lymph node assay.

Autores: J Lalko, A M Api | Ano: 2006 | Database: pubmed

Resumo: Essential oils are commonly used fragrance ingredients. The oils themselves are complex mixtures, which may contain naturally occurring contact sensitizers. The local lymph node assay was used to evaluate the dermal sensitization potential of basil, citronella, clove leaf, geranium, litsea cubeba, lemongrass, and palmarosa oils. Three of the major components--citral, eugenol, and geraniol--were included to investigate any difference in sensitization potential arising from their exposure in a mixture. Each fragrance material was tested at five concentration ranging from 2.5% to 50% w/v in 1:3 ethanol:diethyl phthalate. The stimulation index (SI) values were calculated for each dose level, an SI > or = 3 was considered a positive response. The estimated concentration (EC3) required to elicit a positive was calculated and taken as a measure of relative potency. The EC3 values and potency classification for basil, clove leaf, litsea cubeba, lemongrass and palmarosa oils were calculated to be <2.5% (> or = moderate), 7.1% (weak), 8.4% (weak), 6.5% (weak) and 9.6% (weak), respectively. Citronella and geranium oils were negative. The individual components citral, eugenol and geraniol resulted in EC3 values of 6.3%, 5.4% and 11.4%, respectively. In general, the potency of each essential oil did not differ significantly from that observed for its main individual component.

Resultados: N/A

Conclusão: N/A

Fungicidal potential of essential oils in control of Fusarium spp. and Sclerotinia sclerotiorum/ Potencial fungicida de óleos essenciais no controle de Fusarium spp. e Sclerotinia sclerotiorum

Autores: Fontana, Daniele Cristina; Schmidt, Denise; Kulczynski, Stela Maris; Caron, Braulio Otomar; Pretto, Matheus Milani; Mariotto, Axel Bruno; Santos, Jullie dos; Holz, Evandro | Ano: 2020 | Database: LILACS

Resumo: The use of highly toxic pesticides to control soil pathogens, such as Fusarium spp. and Sclerotinia sclerotiorum has generated concern, due to the irreversible impacts caused on the environment, in addition to selecting resistant isolates. In this way, essential oils appear as an efficient alternative in control of diseases. Facing the problem of soil pathogens control and high antimicrobial fungicide that essential oils present, this work aimed to evaluate the in vitro fungicidal potential of essential oils in control of Fusarium spp. and S. sclerotiorum. A completely randomized design, factorial scheme 2×4×8 was used, with two isolates (Fusarium spp. and S. sclerotiorum), four essential oils (Aloysia citriodora, Cymbopogon winterianus, Lippia alba and Ocimum americanum), eight essential oil concentrations (0.0; 0.2; 0.4; 0.6; 0.8; 1.0; 1.2 and 1.4 ?L·mL-1), and ten replicates. The essential oils inhibited mycelial growth of the fungi in different concentrations, being their potential justified by the presence of antifungal chemical compounds. Essential oils of A. citriodora, C. winterianus, L. alba and O. americanum present high fungicidal potential, being viable alternatives for formulation of commercial products, boosting the pesticides industry.(AU)

Resultados: N/A

Conclusão: N/A

Crescimento, produção de fitomassa e teor de óleo essencial de folhas de capim citronela (Cymbopogon nardus (L. ) Rendle) em cultivo consorciado com algodoeiro colorido no semiárido mineiro/ Growth, phytomass yield and essential oil content of leaves of citronella grass [Cymbopogon nardus (L. ) Rendle] intercropping with colored cotton

Autores: Rocha, H. C. R; Alvarenga, C. D; Giustolin, T. A; Brant, R. S; Souza, M. D. C; Sarmento, H. G. S; Barbosa, M. G | Ano: 2012 | Database: LILACS

Resumo: Avaliou-se o crescimento, a produção e o teor do óleo essencial de dois cortes de capim citronela em cultivo consorciado com algodoeiro colorido no semiárido. Para isso foram utilizados dois sistemas de consórcios (tratamentos): algodão colorido consorciado com capim citronela 3x1 e algodão colorido consorciado com capim citronela 1x1. A variedade de algodão colorido utilizada foi a BRS Rubi e as mudas de capim citronela foram produzidas no Horto de Plantas Medicinais da Unimontes. O delineamento experimental utilizado foi em blocos casualizados com dois tratamentos e 16 repetições. O experimento foi mantido em regime de sequeiro e foi avaliado a altura das plantas de capim citronela. Foram realizadas duas colheitas das folhas de capim citronela, sendo a primeira no momento da colheita da fibra do algodão e a segunda na rebrota do capim, seis meses após. Todas as plantas da parcela foram colhidas e as folhas frescas foram pesadas, no campo, com o auxílio de balança digital. Amostras das folhas colhidas foram retiradas e levadas para secagem em estufa com circulação forçada de ar a 35ºC até atingirem massa constante. Foi verificada a massa seca e posteriormente realizada a extração do óleo essencial pelo método de hidrodestilação em aparelho modificado de Clevenger. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste Skott-Knott (p<0,05). A altura das plantas não diferiu entre os tratamentos nas colheitas. Para a produção de massa fresca e seca houve diferença entre os tratamentos apenas na segunda colheita. Neste caso, as plantas cultivadas em consórcio 1x1 produziram mais do que as do consórcio 3x1. O teor de óleo essencial de capim citronela não variou entre os dois sistemas de consórcio, tanto no primeiro como no segundo corte.

Resultados: N/A

Conclusão: N/A

Synergistic antimicrobial activities of essential oil vapours against Penicillium corylophilum on a laboratory medium and beef jerky.

Autores: Hyegeun Ji, Hoikyung Kim, Larry R Beuchat, Jee-Hoon Ryu | Ano: 2019 | Database: pubmed

Resumo: This study was done to determine the antifungal activities of essential oil (EO) vapours of 97 plants against Penicillium corylophilum and to test combinations of EO vapours for synergistic antifungal effects. Among 97 commercially available EOs extracted from plant parts, garlic, cinnamon bark, may chang (mountain pepper), citronella, thyme thymol, oregano, spearmint, and thyme linalool EO vapours exhibited relatively strong antifungal activities. The minimal inhibitory concentrations of these EO vapours were 0.0390-0.6250 μL/mL. A combination of cinnamon bark, citronella, and may chang EO vapours, as well as a combination of cinnamon bark and citronella EO vapours, showed synergistic inhibitory activities to P. corylophilum on a laboratory medium. A combination of cinnamon bark, citronella, and may chang EO vapours had synergistic activity in inhibiting growth of P. corylophilium on beef jerky. Observations reported here provide basic information valuable when developing strategies to inhibit the growth of P. corylophilum and possibly other moderately xerophilic molds on intermediate-moisture foods.

Resultados: N/A

Conclusão: N/A

Optical Investigation of Essential Oils Using Absorbance and Photoluminescence.

Autores: Fernando Aparecido Dias Radomski, Celso de Araujo Duarte, Evaldo Ribeiro, Eduardo Lemos de Sá | Ano: 2021 | Database: pubmed

Resumo: Essential oils are complex mixtures of organic substances with large commercial importance in the pharmaceutical, food, fragrance, and cosmetic industries due to their organoleptic and biological properties. Also, these materials are also luminescent what has taken several studies about its potential uses for the detection and quality control of essential oils, imaging, and for the investigation of the synergies of their constituents. Concerning this, the present work is dedicated to studying the optical properties of selected essential oils: citronella (Cymbopogon winterianus), Japanese mint (Mentha arvensis), clove bud (Syzygium aromaticum), and bergamot (Citrus bergamia). We carried out a comparative study of the photoluminescence and the ultraviolet-visible optical absorption (abs-UV-Vis) of these essential oils with their typical constituents. To inspect the effects of the intermolecular interactions on the optical response of these systems, mixtures between the essential oils constituents following the expected average percent mass fraction were also studied. From these experiments, the main results were bathochromic effects in the abs-UV-Vis spectra; excimer formation in citral, isopulegol, isomenthone, eugenol, and eugenyl acetate; excimer emission enhancing and specific solvent effect in the essential oils photoluminescence spectra. These results contribute to the knowledge of essential oils' applications, especially in the evaluation of components' interactions through a simple abs-UV-Vis assay.

Resultados: N/A

Conclusão: N/A

Avaliação preliminar de óleos essenciais de plantas como repelentes para Aedes albopictus (Skuse, 1894) (Diptera: Culicidae)/ Preliminary evaluation of plant essential oils as repellents against Aedes albopictus (Skuse, 1894) (Diptera: Culicidae)

Autores: Bueno, V. S; Andrade, C. F. S | Ano: 2010 | Database: LILACS

Resumo: Óleos essenciais de plantas têm sido formulados de forma caseira ou colocados no mercado de forma artesanal para repelir mosquitos hematófagos. O presente trabalho avaliou o possível efeito repelente de alguns excipientes normalmente usados em formulações comerciais e de óleos essenciais de nove plantas, sobre fêmeas de Aedes albopictus. Os testes foram realizados em caixas contendo mosquitos, oferecendo-se uma área definida de dedos da mão tratados ou não. Exceto pelo creme Lanatte e os géis de carbopol, as substâncias excipientes avaliadas mostraram ação repelente. Apenas os óleos provenientes de citronela (5 e 10 por cento) resultaram em repelência expressiva, com índices médiosde proteção acimade 98 por cento. Os resultados indicam que a metodologia empregada é adequada para a avaliação preliminar de produtos com potencial para a repelência de mosquitos.

Resultados: N/A

Conclusão: N/A

In vitro characterization and mosquito (Aedes aegypti) repellent activity of essential-oils-loaded nanoemulsions.

Autores: Onanong Nuchuchua, Usawadee Sakulku, Napaporn Uawongyart, Satit Puttipipatkhachorn, Apinan Soottitantawat, Uracha Ruktanonchai | Ano: 2009 | Database: pubmed

Resumo: The nanoemulsions composed of citronella oil, hairy basil oil, and vetiver oil with mean droplet sizes ranging from 150 to 220 nm were prepared and investigated both in vitro and in vivo. Larger emulsion droplets (195-220 nm) shifted toward a smaller size (150-160 nm) after high-pressure homogenization and resulted in higher release rate. We proposed that thin films obtained from the nanoemulsions with smaller droplet size would have higher integrity, thus increasing the vaporization of essential oils and subsequently prolonging the mosquito repellant activity. The release rates were fitted with Avrami's equations and n values were in the same range of 0.6 to 1.0, implying that the release of encapsulated limonene was controlled by the diffusion mechanism from the emulsion droplet. By using high-pressure homogenization together with optimum concentrations of 5% (w/w) hairy basil oil, 5% (w/w) vetiver oil (5%), and 10% (w/w) citronella oil could improve physical stability and prolong mosquito protection time to 4.7 h due to the combination of these three essential oils as well as small droplet size of nanoemulsion.

Resultados: N/A

Conclusão: N/A

Therapeutic Potential of Citronella Essential Oil: A Review.

Autores: Ruchi Sharma, Rekha Rao, Sunil Kumar, Sheefali Mahant, Sarita Khatkar | Ano: 2019 | Database: pubmed

Resumo: Mosquito-borne diseases such as malaria, filariasis, chikunguniya, yellow fever, dengue and Japanese encephalitis are the major cause of remarkable morbidity and mortality in livestock and humans worldwide. Since ancient times, aromatic plants are used for their medicinal value. Essential oils derived from these plants may be used as effective alternatives/adjuvants in pharmaceuticals, biomedical, cosmetic, food, veterinary and agriculture applications. These oils have also gained popularity and interest for prevention and treatment of various disorders. However, several reports on adverse effects including skin eruption, contact artricaria or toxic encephalopathy in children are available for synthetic repellent in the literature. Thus, natural insect repellents like essential oils have been explored recently as an alternative. One such essential oil studied widely, is citronella oil, extracted mainly from Cymbopogon nardus. This essential oil has exhibited good efficacy against mosquitoes. It is a mixture of components including citronellal, citronellol, geraniol as major constituents contributing to various activities (antimicrobial, anthelmintic, antioxidant, anticonvulsant antitrypanosomal and wound healing), besides mosquito repellent action. Citronella essential oil is registered in US EPA (Environmental protection agency) as insect repellent due to its high efficacy, low toxicity and customer satisfaction. However, poor stability in the presence of air and high temperature limits its practical applications. Since specific knowledge on properties and chemical composition of oil is fundamental for its effective application, the present review compiles and discusses biological properties of citronella oil. It also sheds light on various formulations and applications of this essential oil.

Resultados: N/A

Conclusão: N/A

Therapeutic Potential of Citronella Essential Oil: A Review.

Autores: Ruchi Sharma, Rekha Rao, Sunil Kumar, Sheefali Mahant, Sarita Khatkar | Ano: 2019 | Database: pubmed

Resumo: Mosquito-borne diseases such as malaria, filariasis, chikunguniya, yellow fever, dengue and Japanese encephalitis are the major cause of remarkable morbidity and mortality in livestock and humans worldwide. Since ancient times, aromatic plants are used for their medicinal value. Essential oils derived from these plants may be used as effective alternatives/adjuvants in pharmaceuticals, biomedical, cosmetic, food, veterinary and agriculture applications. These oils have also gained popularity and interest for prevention and treatment of various disorders. However, several reports on adverse effects including skin eruption, contact artricaria or toxic encephalopathy in children are available for synthetic repellent in the literature. Thus, natural insect repellents like essential oils have been explored recently as an alternative. One such essential oil studied widely, is citronella oil, extracted mainly from Cymbopogon nardus. This essential oil has exhibited good efficacy against mosquitoes. It is a mixture of components including citronellal, citronellol, geraniol as major constituents contributing to various activities (antimicrobial, anthelmintic, antioxidant, anticonvulsant antitrypanosomal and wound healing), besides mosquito repellent action. Citronella essential oil is registered in US EPA (Environmental protection agency) as insect repellent due to its high efficacy, low toxicity and customer satisfaction. However, poor stability in the presence of air and high temperature limits its practical applications. Since specific knowledge on properties and chemical composition of oil is fundamental for its effective application, the present review compiles and discusses biological properties of citronella oil. It also sheds light on various formulations and applications of this essential oil.

Resultados: N/A

Conclusão: N/A

Therapeutic Potential of Citronella Essential Oil: A Review.

Autores: Ruchi Sharma, Rekha Rao, Sunil Kumar, Sheefali Mahant, Sarita Khatkar | Ano: 2019 | Database: pubmed

Resumo: Mosquito-borne diseases such as malaria, filariasis, chikunguniya, yellow fever, dengue and Japanese encephalitis are the major cause of remarkable morbidity and mortality in livestock and humans worldwide. Since ancient times, aromatic plants are used for their medicinal value. Essential oils derived from these plants may be used as effective alternatives/adjuvants in pharmaceuticals, biomedical, cosmetic, food, veterinary and agriculture applications. These oils have also gained popularity and interest for prevention and treatment of various disorders. However, several reports on adverse effects including skin eruption, contact artricaria or toxic encephalopathy in children are available for synthetic repellent in the literature. Thus, natural insect repellents like essential oils have been explored recently as an alternative. One such essential oil studied widely, is citronella oil, extracted mainly from Cymbopogon nardus. This essential oil has exhibited good efficacy against mosquitoes. It is a mixture of components including citronellal, citronellol, geraniol as major constituents contributing to various activities (antimicrobial, anthelmintic, antioxidant, anticonvulsant antitrypanosomal and wound healing), besides mosquito repellent action. Citronella essential oil is registered in US EPA (Environmental protection agency) as insect repellent due to its high efficacy, low toxicity and customer satisfaction. However, poor stability in the presence of air and high temperature limits its practical applications. Since specific knowledge on properties and chemical composition of oil is fundamental for its effective application, the present review compiles and discusses biological properties of citronella oil. It also sheds light on various formulations and applications of this essential oil.

Resultados: N/A

Conclusão: N/A

In vitro characterization and mosquito (Aedes aegypti) repellent activity of essential-oils-loaded nanoemulsions.

Autores: Onanong Nuchuchua, Usawadee Sakulku, Napaporn Uawongyart, Satit Puttipipatkhachorn, Apinan Soottitantawat, Uracha Ruktanonchai | Ano: 2009 | Database: pubmed

Resumo: The nanoemulsions composed of citronella oil, hairy basil oil, and vetiver oil with mean droplet sizes ranging from 150 to 220 nm were prepared and investigated both in vitro and in vivo. Larger emulsion droplets (195-220 nm) shifted toward a smaller size (150-160 nm) after high-pressure homogenization and resulted in higher release rate. We proposed that thin films obtained from the nanoemulsions with smaller droplet size would have higher integrity, thus increasing the vaporization of essential oils and subsequently prolonging the mosquito repellant activity. The release rates were fitted with Avrami's equations and n values were in the same range of 0.6 to 1.0, implying that the release of encapsulated limonene was controlled by the diffusion mechanism from the emulsion droplet. By using high-pressure homogenization together with optimum concentrations of 5% (w/w) hairy basil oil, 5% (w/w) vetiver oil (5%), and 10% (w/w) citronella oil could improve physical stability and prolong mosquito protection time to 4.7 h due to the combination of these three essential oils as well as small droplet size of nanoemulsion.

Resultados: N/A

Conclusão: N/A

The effects of plant essential oils on escape response and mortality rate of Aedes aegypti and Anopheles minimus.

Autores: Sunaiyana Sathantriphop, Nicole L Achee, Unchalee Sanguanpong, Theeraphap Chareonviriyaphap | Ano: 2015 | Database: pubmed

Resumo: The High Throughput Screening System (HITSS) has been applied in insecticide behavioral response studies with various mosquito species. In general, chemical or natural compounds can produce a range of insect responses: contact irritancy, spatial repellency, knock-down, and toxicity. This study characterized these actions in essential oils derived from citronella, hairy basil, catnip, and vetiver in comparison to DEET and picaridin against Aedes aegypti and Anopheles minimus mosquito populations. Results indicated the two mosquito species exhibited significantly different (P<0.05) contact irritant escape responses between treatment and control for all tested compound concentrations, except with the minimum dose of picaridin (P>0.05) against Ae. aegypti. Spatial repellency responses were elicited in both mosquito species when exposed to all compounds, but the strength of the repellent response was dependent on compound and concentration. Data show that higher test concentrations had greatest toxic effects on both mosquito populations, but vetiver had no toxic effect on Ae. aegypti and picaridin did not elicit toxicity in either Ae. aegypti or An. minimus at any test concentration. Ultimately, this study demonstrates the ability of the HITSS assay to guide selection of effective plant essential oils for repelling, irritating, and killing mosquitoes.

Resultados: N/A

Conclusão: N/A

The fabrication and assessment of mosquito repellent cream for outdoor protection.

Autores: Hemanga Hazarika, Harshita Krishnatreyya, Varun Tyagi, Johirul Islam, Neelutpal Gogoi, Danswrang Goyary, Pronobesh Chattopadhyay, Kamaruz Zaman | Ano: 2022 | Database: pubmed

Resumo: Mosquito-borne infections like dengue, malaria, chikungunya, etc. are a nuisance and can cause profound discomfort to people. Due to the objectional side effects and toxicity associated with synthetic pyrethroids, N,N-diethyl-3-methylbenzamide (DEET), N,N-diethyl phenylacetamide (DEPA), and N,N-di ethyl benzamide (DEBA) based mosquito repellent products, we developed an essential oil (EO) based mosquito repellent cream (EO-MRC) using clove, citronella and lemongrass oil. Subsequently, a formulation characterization, bio-efficacy, and safety study of EO-MRC were carried out. Expression of Anti-OBP2A and TRPV1 proteins on mosquito head parts were studied by western blotting. In-silico screening was also conducted for the specific proteins. An FT-IR study confirmed the chemical compatibility of the EOs and excipients used in EO-MRC. The thermal behaviour of the best EOs and their mixture was characterized by thermogravimetric analysis (TGA). GC-MS examination revealed various chemical components present in EOs. Efficacy of EO-MRC was correlated with 12% N,N-diethyl benzamide (DEBA) based marketed cream (DBMC). Complete protection time (CPT) of EO-MRC was determined as 228 min. Cytotoxicity study on L-132 cell line confirmed the non-toxic nature of EO-MRC upon inhalation. Acute dermal irritation study, acute dermal dose toxicity study, and acute eye irritation study revealed the non-toxic nature of EO-MRC. Non-target toxicity study on Danio rerio confirmed EO-MRC as safer for aquatic non-target animals. A decrease in the concentration of acetylcholinesterase (AChE) was observed in transfluthrin (TNSF) exposed Wistar rats. While EO-MRC did not alter the AChE concentrations in the exposed animals. Results from western blotting confirmed that Anti-OBP2A and TRPV1 proteins were inhibited in TNSF exposed mosquitoes. Mosquitoes exposed to EO-MRC showed a similar expression pattern for Anti-OBP2A and TRPV1 as the control group. In silico study revealed eight identified compounds of the EOs play significant roles in the overall repellency property of the developed product. The study emphasizes the mosquito repellent activity of EO-MRC, which could be an effective, eco-friendly, and safer alternative to the existing synthetic repellents for personal protection against mosquitoes during field conditions.

Resultados: N/A

Conclusão: N/A

Toxicidade de óleos essenciais de eucalipto e citronela sobre Sitophilus zeamais Motschulsky (Coleoptera: curculionidae)/ Toxicity of essential oils of eucalyptus and citronella on Sitophilus zeamais Motschulsky (Coleoptera: curculionidae)

Autores: Ootani, Marcio Akio; Aguiar, Raimundo Wagner de Souza; Mello, Aurélio Vaz de; Didonet, Julcemar; Portella, Augustus Caeser Franke; Nascimento, Ildon Rodrigues do | Ano: 2011 | Database: LILACS

Resumo: As análises realizadas por cromatografia gasosa acoplada à espectrometria de massas CG/EM apresentou o citronelal como o principal fitoconstituinte dos óleos essenciais de Corymbia citriodora Hill & Johnson, e Cymbopogon nardus (L.), com 61,78 e 36,53%, respectivamente. A toxicidade dos óleos essenciais e do citronelal foi verificada para Sitophilus zeamais por meio das estimativas das curvas de concentrações resposta e tempos de exposição letais para 50 e 95% dos insetos (CL50, CL95, TL50 e TL95). A toxicidade do citronelal foi maior para S. zeamais, com CL50 e CL95 de 0,340 e 0,820µL/cm2 e TL50 e TL95 de 11,89 e 59,50h, respectivamente. A repelência de S. zeamais foi maior para os óleos essenciais de C. nardus e C. citriodora nas concentrações de 0,660; 0,881; 1,101 e 1,321µL/cm2 com 86,6 a 98,8%. O número de insetos emergidos dos grãos pulverizados com os óleos essenciais foi maior para o citronelal nas concentrações de 0,330; 0,440; 0,550, e 0,660µL/cm2 . A redução da massa de grãos foi menor para aqueles grãos tratados com C. citriodora e C. nardus. Óleos essenciais de C. citriodora e C. nardus podem proteger produtos armazenados pelo dano causado por S. zeamais.

Resultados: N/A

Conclusão: N/A