In vitro antimicrobial activity of certain plant products / seed extracts against multidrug resistant Propionibacterium acnes, Malassezia furfur, and aflatoxin producing Aspergillus flavus

Seed extracts of five different plants viz. Phoenix sylvestris, Tamarindus indica, Syzygium cumini, Manilkara zapota, and Annona squamosa, prepared by microwave assisted extraction (MAE) method were screened for their antimicrobial activity against various human pathogenic microbes. Extraction efficiency ranged from 6-24%. Antimicrobial activity of seed extracts was investigated against three yeasts (Candida albicans, Saccharomyces cerevisae, Malassezia furfur), one mold (Aspergillus flavus) and one anaerobic bacterium (Propionibacterium acnes) by broth dilution assay and minimum inhibitory concentration (MIC) was determined. Methanolic extract of T. indica and S. cumini inhibited 60% of test organisms. Amongst the microorganisms tested, the most resistant was found to be C. albicans and the most susceptible was M. furfur. Effect of eight seed extracts on aflatoxin production by A. flavus was also investigated. Ethanolic extract of A. squamosa caused 100% inhibition of aflatoxin production at 500 µg/mL