Research on antibacterial activities of extract of sweet potato polyphenols

Antibacterial activities were tested using MIC,MBC and inhibitory bacteria rate as index.The influence of temperature, pH on antibacterial activity was also investigated. The results indicated that the extract showed obvious antibacterial action to Escherichia coli, Staphylococcus aureus, Bacilus cereus, Especially to Staphylococcus aureus, while showed only certain antibacterial action to Bacillus subtilis, Saccgaromyces cerevisiae, Aspergillus niger and Hansenula sp . even with high concentration. It was also proved that the extract had good thermal stability, and showed highest antibacterial activity on Escherichia coli, Staphylococcus aureus, and Bacillus subtilis from pH 4 to 5.