Abstract:The antimicrobial activity and antibacterial stability of polyphenols from black chokeberry on five kinds of bacteria and two kinds of fungi were investigated in this study. The bacteriostatic activity of polyphenols from black chokeberry was determined according to the diameter of bacteriostasis zone by double-layer plate perforating method. The minimum inhibitory concentrations (MICs) of polyphenols from black chokeberry against five bacteria were determined by spectrophotometry method. The effects of salt concentration, temperature and UV irradiation on the antibacterial stability of polyphenols from black chokeberry were investigated by using Alicyclobacillus and Bacillus subtilis as indicator bacteria. The results showed that the polyphenols from black chokeberry had good antibacterial activities against five kinds of bacteria, such as Alicyclobacillus and Bacillus subtilis, but no antibacterial effect on the two kinds of fungi. The MIC of polyphenols from black chokeberry against Alicyclobacillus (DSM 3922, AAT-92) and Enterobacter cloacae (20051) was 0.40 g/L, and the MICs of polyphenols from black chokeberry against Bacillus subtilis. (10034) and Enterobacter aerogenes (10017) were 0.05 g/L and 0.10 g/L, respectively. With the increase of NaCl concentration, the antimicorbial activity of polyphenols from black chokeberry decreased significantly. After the heat treatment, the antibacterial activity of polyphenols from black chokeberry decreased slightly, and the antibacterial activity did not change after UV treatment.
