Total Polyphenol Content and Antibacterial Activity of Mulberry Leaf Extracts from Different Polarity Solvents

Active substances were extracted from mulberry leaf powder using different polarity solvents.As a result,mulberry leaf ethyl acetate extract,butyl alcohol extract and water extract were obtained.The antibacterial effect of mulberry leaf extracts from different polarity solvents was evaluated with the agar punch diffusion method.The results showed that mulberry leaf extracts from different polarity solvents had certain inhibitory effect on both Gram-positive and Gram-negative bacteria for test.The antibacterial effect of ethyl acetate extract was significantly better than that of other extracts.Its minimum inhibitory concentration(MIC) to Escherichia coli was 6.3 mg/mL,and its MIC to all Staphyloccocus aureus,Bacillus subtilis and Salmonella sp.was 12.5 mg/mL.The total polyphenol content of ethyl acetate extract was(11.91±0.67) mg/g,also significantly higher than that of other extracts,indicating that the antibacterial activity and the total polyphenol content of mulberry leaf extracts from different polarity solvents have a significant dose response relationship(P0.05).