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Título [PT]: Atividade antifúngica de Stryphnodendron adstringens (Mart.) Coville sobre leveduras de isolados clínicos
Autor(es): Kelly Ishida
Palavras-chave [PT]:

Stryphnodendron adstringens. Atividade antifúngica. Taninos. Agente antifúngico. Barbatimão. Ensaio biológico. Candida albicans. Brasil.

Antifungal. Barbatimão. Candida sp. Stryphnodendron adstringens. Yeast. Brazil.

Celso Vataru Nakamura [Orientador] - UEM

Resumo: Em recursos naturais, principalmente plantas, têm se buscado moléculas bioativas que podem se tornar uma alternativa para o desenvolvimento de novos agentes antifúngicos com menos efeitos colaterais, amplo espectro de ação e menor custo. Assim, o objetivo deste trabalho foi verificar o efeito do extrato bruto, frações e subfrações de Stryphnodendron cidstringens (Mart.) Covilie, popularmente conhecido como "barbatimão", sobre leveduras isoladas de fluido vaginal. Amostras de fluido vaginal foram coletadas de 506 pacientes ambulatoriais, sendo que 103 apresentaram cultura positiva para leveduras (20,35%). Dentre essas, 96/103 (93,2%) foram identificadas como Candida albicans, 6 como C. não albicans (1 C. parapsilosis, 1 C. tropicalis e 4 Candida sp.) e uma amostra como não pertencente ao gênero Candida. Todas as amostras foram susceptíveis aos poliênicos, e somente 7,76 % resistentes ou susceptível dose dependente ao fluconazol. A maioria das amostras produziram protease ácida (99%), fosfolipase (83%) e hemolisina (9 1,3%). A aderência de leveduras em células Vero foi variada, sendo que 67,9% das amostras apresentaram aderência de 50 a 1 50%, e a maioria possuem características hidrofihicas. As amostras foram susceptíveis aos extratos de S. adsiringens em concentrações superiores a 7,8 µg/mL mostrando somente atividade fungistática. A subfração F2.4 do "barbatimão" inibiu a formação do tubo germinativo em concentrações ≥15,75 µg/mL, e um aumento significativo de brotamentos (188,34%) foi observado em leveduras tratadas com 125 µg/mL. A inibição da aderência de leveduras em células e superfície abiótica foi dose dependente. A subfração F2.4 reduziu a hidrofobicidade de superfície celular. Através da metodologia empregada nesse estudo, não foi possível detectar a inibição da atividade de enzimas extracelulares de Candida spp. Interações da subfração F2.4 com anfotericina B, fluconazol e nistatina não foram sinérgicas. Através da microscopia óptica e de varredura pôde-se observar a inibição na formação de pseudohifas e efeito aglutinante da subfração F2.4. Irregularidades na parede celular de Ieveduras tratadas com a subfração F2.4 também foram visualizadas, e a microscopia eletrônica de transmissão evidenciou o efeito sobre a parede celular. Adicionalmente, a estimulação macrofágica foi verificada quando as leveduras eram previamente tratadas com 7%8 µg/mL da subfração F2.4 por 2 h, observando um aumento de 28% em relação ao controle. A citotoxicidade dos extratos do "barbatimão" foi observada sobre células Vero e macrófagos com CC50 acima de 100 µg/mL. Por outro lado, para hemácias e larvas de Artemia salina a CC50 e DL50 foram superiores a 1000 µg/mL, exceto para a subfração F2.4 com DL50 de 100 µg/mL. Provavelmente a atividade antifúngica da subfração F2.4 observada neste trabalho se atribui às proantocianidinas poliméricas triidroxilados no anel B e presença dc ácido gálico na sua estrutura, com estimativa de peso molecular médio de 2.000 Da. Abstract: In natural products, mainly plants, have searched bioactivies compounds which can become an alternative for development of news antifungal agents with fewer side effects, a greater spectrum of action and Low cost. So, the aim of this study was verify the effect of rude extract, fractions, and sub-fractions otained from Stryphnodendron adstringens (Mart.) Coville, known as "barbatimão", on yeasts isolated from vaginal fluid. Of 506 vaginal fluid sampIes, 103 had positive culture on dextrose Sabouraud ágar (20.35%). Ninety and six sampIes were identified as Candida albicans and, six C. non- albicans (1 C. parapsilosis, 1 C. tropicalis and 4 Candida sp). One no concern genus Candida. All yeasts were susceptible to polyenes and, just 7.76% were resistants or dose dependent susceptible. The most of yeast produced acid protease (99%), phospholipase (83%) and hemolysin (91.3%). Adherence on Vero cells was varied, being 67.9% with 50 to 150 yeasts/100 cells, and the most had hydrophilics characteristics. The extracts of S. adstringens showed antifungal activity in concentration above 7.8 µg/mL, however just fungistatic action. The sub-fraction F2.4 inhibited the germinative tube formation in concentrations 15.75 In natural products, mainly plants, have searched bioactivies compounds which can hconic an alternative for development of news antifungal agents with fewer side effects, a ienter spectrum of action and Low cost. So, the aim of this study was verify the effect of rude extract, fractions, and sub-fractions obtained from Stryphnodendron adstringens (Mart.) Coville, known as "barbatirnão", on yeasts isolated from vaginal fluid. Of 506 vaginal fluid umpIes, 103 had positive culture on dextrose Sabouraud ágar (20.35%). Ninety and six anipIes were identified as Candida albicans and, six C. non- albicans (1 C. parapsilosis, 1 C. fropicalis and 4 Candida sp). One no concern genus Candida. All yeasts were susceptible to polycncs and, just 7.76% were resistants or dose dependent susceptible. The most of yeast produced acid protease (99%), phospholipase (83%) and hemoLysin (91.3%). Adherence on Vem edis was varied, being 67.9% with 50 to 150 yeasts/100 cells, and the most had hydrophilics characteristics. The extracts of 8. adstringens showed antifungal activity in onccntration above 7.8 µg/mL, however just fungistatic action. The sub-fraction F2.4 inhibited the germinative tube formation in concentrations 15.75 µg/mL and significative ncrcase of buddings (188.34%) was observed in yeasts treated with 125 µg/mL. Adherence inhibition of yeast on cell and a biotic surface was dependent dose. The sub-fraction F2.4 reduced the cellular surface hydrophobicity. In this study was not possible verify the inhibition of extracellular enzymes activities. Combinations of sub-fraction F2.4 with amphotericin B, nystatin or fluconazole were not synergic. Through optic and scanning cletronic microscopy can be observed the inhibition in pseudohyphal formation and aggiutinant effect of sub-fraction F2.4. Irregularity on cell wall of yeasts treated was observed and transrnission eietronic microscopy showed evidence of the effect of "barbatimão" on yeast wall cdl. Additionally, the macrophage stimulation was verify when the yeasts were tu(ccI previously with 7.8 µg/mL of sub-fraction F2.4 by 2 h, observing increase of 28% iimpared with control group. Cytotoxicity effect ofextracts obtained from "barbatirnão" was hNeaved on Vero and rnacrophages celis with CC50 above 100 µg/mL. On the other hand, for hlood red ccli and Aflemia salina grub the CC50 and DL50 were >1,000 µg/mL, except for subl (ion F2.4, which DL50 was 100 jig/mL. Probably the antifungal activity of sub-fraction 1 /4 is attributed the polyrners proanthocyanidins tri-hydroxylated in ring B and presence of acid Iinked in structure ofpolymer, with median molecular weight of 2,000 15.75 µg/mL and significative ncrcase of buddings (188.34%) was observed in yeasts treated with 125 µg/mL. Adherence inhibition of yeast on cell and a biotic surface was dependent dose. The sub-fraction F2.4 reduced the cellular surface hydrophobicity. In this study was not possible verify the inhibition of extracellular enzymes activities. Combinations of sub-fraction F2.4 with amphotericin B, nystatin or fluconazole were not synergic. Through optic and scanning cletronic microscopy can be observed the inhibition in pseudohyphal formation and aggiutinant effect of sub-fraction F2.4. Irregularity on cell wall of yeasts treated was observed and transrnission eietronic microscopy showed evidence of the effect of "barbatimão" on yeast wall cdl. Additionally, the macrophage stimulation was verify when the yeasts were tu(ccI previously with 7.8 µg/mL of sub-fraction F2.4 by 2 h, observing increase of 28% iimpared with control group. Cytotoxicity effect ofextracts obtained from "barbatirnão" was hNeaved on Vero and rnacrophages celis with CC50 above 100 jig/mL. On the other hand, for hlood red ccli and Aflemia salina grub the CC50 and DL50 were >1,000 µg/mL, except for sub-fraction F2.4, which DL50 was 100 µg/mL. Probably the antifungal activity of sub-fraction 1 /4 is attributed the polyrners proanthocyanidins tri-hydroxylated in ring B and presence of acid Iinked in structure ofpolymer, with median molecular weight of 2,000 Da.

Idioma: Português Data de Publicação: 2006 Local de Publicação: Maringá, PR Orientador: Prof. Dr. Celso Vataru Nakamura Co-Orientador: Prof. Dr. Benedito Prado Dias Filho Instituição: Universidade Estadual de Maringá. Departamento de Farmácia e Farmacologia Nível: Dissertação (mestrado em Ciências Farmacêuticas) UEM: Programa de Pós-Graduação em Ciências Farmacêuticas

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