Phenolic plant extracts versus penicillin G: In vitro susceptibility of Staphylococcus aureus isolated from bovine mastitis

• Autor(a) principal: Gomes, Fernanda
• Data de Publicação: 2018
• Outros Autores: Rodrigues, Maria Elisa, Martins, Natália, Ferreira, Isabel C.F.R., Henriques, Mariana
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10198/20261
• topic: Bovine mastitis; Eucalyptus globulus Labill; Juglans regia L.; Penicillin G; Staphylococcus aureus

Antibiotics are the elective drugs in bovine mastitis (BM) treatment, despite their low rates of e ciency and e ectiveness and increasing risk of pathogen resistance. In this sense, it is urgent to discover new and e ective antimicrobial agents to apply in BM control and even treatment. Plant extracts have been widely recognized as a rich source of phytochemicals with antimicrobial potential. Thus, the present work aims to compare the bioactivity of Eucalyptus globulus and Juglans regia extracts against Staphylococcus aureus bovine mastitis strains with penicillin G. At non-toxic concentrations, E. globulus exerted a bacteriostatic e ect in planktonic cells and J. regia had no antimicrobial activity. Penicillin G, at minimum inhibitory concentration (MIC), demonstrated bactericidal activity, but just for S. aureus 3, 5, 6 and ATCC 25923, while the other strains seem to have acquired resistance. On the other hand, E. globulus and penicillin G in combination demonstrated synergy, being the most e ective approach against S. aureus 1, 2 and 4. Thus, penicillin alone and in combination with E. globulus or J. regia seems to be promissory strategies to control bovine mastitis infections.