Several researches have been developed to search for new antimicrobial agents from extracts of plants and other natural products to be used in pharmaceutical and cosmetic products. Nowadays there are many methods to evaluate the antibacterial and antifungal activity of the plant extracts. The most known assays have been based on diffusion in agar; and micro and macrodilution methods. The purpose of this review is to describe the different methods commonly used for the determination of new antimicrobial agents from the plants extracts and elucidate the main interference factors. Moreover, this contributes as research source for future development of investigations related to the study of antimicrobial activity from natural products.
Antimicrobial activity; agar diffusion; microdilution; macrodilution; minimal inhibitory concentration (MIC); plant extract