Atividade antibacteriana in vitro de extratos e substâncias isoladas de espécies de Croton frente Staphylococcus aureus causador de mastite bovina

• Autor(a) principal: Nader, Talita Thomaz [UNESP]
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/122216
• topic: Croton (Botânica); Extratos vegetais; Biofilme; Staphylococcus aureus; Produtos de ação antimicrobiana; Plant extracts

The present study aimed to evaluate the potential antimicrobial activity of plant extracts and substances isolated from Croton antisyphiliticus and C. urucurana, species in the Cerrado, against strains of Staphylococcus aureus isolated from milk of cows with mastitis. The microorganisms were grown in free form and in biofilm. The extracts were evaluated for their ability to inhibit biofilm formation and eradication. We used the antibiotic gentamicin as a comparison and vancomycin as negative control. The plants were collected in the dry and rainy season. Quantification of antimicrobial activity was performed using the crystal violet and count of colony forming units. The results show that both species inhibited the biofilm formation of S. aureus. The crude extract and fractions of C. antisyphiliticus presented antimicrobial activity similar to gentamicin, while the plant compounds with non polar characteristics, arising from C. urucurana were significantly more active in cells in biofilms of S. aureus that the antibiotic vancomycin, reducing around 5 logs of the bacterial population. In the conditions tested, there was no seasonal influence on antimicrobial activity of the extracts. Between the two species of Croton evaluated, between the two Croton species evaluated, it is concluded that C. urucurana was the most promising antimicrobial activity against strains of S. aureus causing bovine mastitis