Análise fitoquímica e atividade antifúngica do óleo essencial de folhas de Lippia sidoides Cham. e do Timol contra cepas de Candida spp / Phytochemical analysis and antifungal activity of the essential oil of Lippia sidoides Cham. and of the Thymol against Candida strains

RESUMO A resistência de fungos do gênero Candida aos fármacos químicos tem lançado o desafio de se identificar novas substâncias que possuam atividade antibiótica ou venham a modular o efeito de produtos atualmente usados contra candidíase. O presente estudo avaliou a atividade antifúngica do óleo essencial de Lippia sidoides Cham. e do timol, sobre cepas de Candida. Inicialmente os produtos foram testados frente a 16 cepas fúngicas pela técnica de difusão em meio sólido, o que permitiu selecionar linhagens para continuidade da pesquisa. Com as linhagens de Candida krusei (CK LMBM 01, CK LMBM 02), Candida albicans (CA LM 62) e Candida tropicalis (CT LM 20), procedeu-se, por microdiluição em caldo, a determinação da Concentração Inibitória Mínima (CIM) e em meio sólido, a Concentração Fungicida Mínima (CFM) dos produtos foi identificada. O microcultivo das leveduras em meio empobrecido foi realizado para verificação de alterações morfológicas e, além disso, uma análise da composição química do óleo foi realizada por Cromatografia Gasosa acoplada à espectrometria de massas (CG-EM). Nesta análise, o constituinte majoritário foi o timol (84,95%), seguido de compostos como p-cimeno e Éter metil carvacrol, entre outros. A CIM do óleo essencial de Lippia sidoides Cham. frente às cepas variou entre 64 e 256 μg/mL, enquanto a CIM do timol foi estabelecida entre 32 e 64 μg/mL. A CFM do óleo essencial foi determinada entre 128 e 512 μg/mL e para o timol foram encontrados valores entre 64 e 128 μg/mL. Em relação à análise micromorfológica, verificada nas concentrações de CIM e CIM x 2, o óleo essencial inibiu o dimorfismo das cepas CK 01 e CT 20 na CIM e quando foi ensaiado o timol, este, na CIM, impediu a transição morfológica das cepas CK 01 e CA 62. Uma redução da morfogênese também foi obsevada na cepa CT 20, porém apenas em CIM x 2 e de forma mais discreta. Os resultados enaltecem o potencial antifúngico de L. sidoides e de seu composto majoritário timol tanto no combate à Candida quanto na neutralização de um dos fatores de virulência, a capacidade invasiva por formação de hifas e pseudohifas verificado na condição patogênica da candidíase. Estes dados são promissores e poderão incentivar futuras pesquisas sobre os aspectos fitoquímicos, toxicológicos e farmacológicos tanto do óleo essencial de Lippia sidoides como também de seus componentes químicos.

ABSTRACT The resistance of the Candida against drugs has been a challenge to the discovery of new substances with antimicrobial or modulatory effects that could be used against the cadidiasis. This work evaluated the antifungal activity of the essential oil of Lippia sidoides Cham. and of the Thymol against Candida strains. The products were tested towards 16 strains of Candida using the diffusion method, which allowed to select the strains in order to proceed with the research. The strains of Candida krusei (CK LMBM 01, CK LMBM 02), Candida albicans (CA LM 62) and Candida tropicalis (CT LM 20) were assayed by the microdilution method so that the Minimal Inhibitory Concentration (MIC) and the Minimal Fungicide Concentration (MFC) could be determined. The morphogenesis of the Candida was evaluated using poor environment in order to observe morphological changes. The composition of the essential oil was determined by GC-MS. The main compound observed was the thymol (84.95%). The MIC of the essential oil of L. sidoides and Thymol ranged between 64 to 256 μg/mL, and between 32 to 64 μg/mL respectively. The MFC of the essential oil and the thymol varied between 128 to 512 μg/mL and 64 to 128 μg/mL respectively. The morphogenesis of different Candida strains was inhibited in the MIC and MICx2 to the essential oil and thymol. The results indicated the antifungal potential of the L. sidoides and of the Thymol due to the inhibition of the invasive capacity, one of the most important virulence factors for the candidiasis` development. These results are promising to new researches about the phytochemical, toxicological and pharmacological aspects of the essential oil of L. sidoides and its phytochemical compounds.

Carum copticum and Thymus vulgaris oils inhibit virulence in Trichophyton rubrum and Aspergillus spp

Emergence of drug-resistant strains has demanded for alternative means of combating fungal infections. Oils of Carum copticum and Thymus vulgaris have long been used in ethnomedicine for ailments of various fungal infections. Since their activity has not been reported in particular against drug-resistant fungi, this study was aimed to evaluate the effects of oils of C. copticum and T. vulgaris on the growth and virulence of drug-resistant strains of Aspergillus spp. and Trichophyton rubrum. The gas chromatography-mass spectrometry analysis revealed thymol constituting 44.71% and 22.82% of T. vulgaris and C. copticum, respectively. Inhibition of mycelial growth by essential oils was recorded in the order of thymol > T. vulgaris > C. copticum against the tested strains. RBC lysis assay showed no tested oils to be toxic even up to concentration two folds higher than their respective MFCs. Thymol exhibited highest synergy in combination with fluconazole against Aspergillus fumigatus MTCC2550 (FICI value 0.187) and T. rubrum IOA9 (0.156) as determined by checkerboard method. Thymol and T. vulgaris essential oil were equally effective against both the macro and arthroconidia growth (MIC 72 µg/mL). A > 80% reduction in elastase activity was recorded for A. fumigatus MTCC2550 by C. copticum, T. vulgaris oils and thymol. The effectiveness of these oils against arthroconidia and synergistic interaction of thymol and T. vulgaris with fluconazole can be exploited to potentiate the antifungal effects of fluconazole against drug-resistant strains of T. rubrum and Aspergillus spp.

Estudios sobre el niño desnutrido. IV pruebas del fucionamiento hepático en el preescolar sano y en el desnutrido, en el niño pelagroso y en el infectado / Studies in malnourished children. IV. Hepatic tests in the healthy, and in the malnourished preschool child; in the pellagrose, and in the infected

Se practicaron las pruebas de retención de la bromosulfaleína y la dosificación de bilirrubina directa e indirecta en un grupo de niños desnutridos, sin encontrar anormalidad en los resultados. En un grupo de 50 niños considerados sanos, se realizaron las pruebas de cefalín-colesterol y de timol. Otro tanto se hizo con 58 desnutridos simples y 48 pelagrosos estudiados separadamente, según existiese o no en ellos, la infección. Por lo que respecta a las pruebas de tinol y de cefalín-colesterol en los preescolares estudiados, se encontró lo siguiente: a) En la desnutrición simple, ligera o avanzada, no se modificaron las pruebas funcionales hepáticas empleadas por nosotros. b) En los niños con pelagra sin complicación infecciosa tampoco se encontraron alteradas las pruebas de funcionamiento hepático. c) Las pruebas anormales de timol que se encontraron en los niños desnutridos o pelagrosos, deben ser atribuidas a la infección o a procesos de regeneración hepática. d) Los resultados anormales de la prueba de cefalín-colesterol que se encontraron en los niños desnutridos y pelagrosos deben ser atribuidos exclusivamente a la infección

Evaluation of certain pharmaceutical preparations containing volatile oil constituents

Chromatographic techniques, viz. TLC, GLC and/or HPLC are applied for the evaluation of Mintoline mouth wash and gargle as well as capsules of Nigellar, Natural Rowatinex, Garline and Gensaline. Those techniques were successfully used for the qualitative and quantitative analyses of the volatile constituents in the studied preparations. Results obtained were found to be in good agreement with the claimed content in each preparation

Evaluation of alkaloidally formulation by Glc

Chromatographic techniques, viz. TLC, GLC and/or HPLC are applied for the evaluation of Mintoline mouth wash and gargle as well as capsules of Nigellar, Natural Rowatinex, Garline and Gensaline. Those techniques were successfully used for the qualitative and quantitative analyses of the volatile constituents in the studied preparations. Results obtained were found to be in good agreement with the claimed content in each preparation

Sensitive colorimetric method for the determination of thymol and eugenol in volatile oils

A simple, rapid and direct method for the determination of thymol and eugenol in volatile oils was presented. It was based on the reaction of these compounds with 3-methyl-2-benzothiazolone hydrazone hydrochloride in the presence of cerric ammonium sulfate and direct measurement at 510 nm. The results obtained were encouraging and reasonably reproducible with a relative st and ard deviation less than 1%