Antioxidant and antimicrobial activities of the polyphenol from purple cabbage

Antioxidant and antimicrobial activities of purple cabbage polyphenol were studied in this paper.The purple cabbage polyphenol was extracted by organic solvent.The antioxidant activities of polyphenol were investigated by scavenging DPPH free radical, hydroxyl radical, superoxide anion, H₂O₂free radical and the growth of microorganism.The inhibitions were also measured through testing lipid oxidation in the experiment.The results showed that the polyphenol of purple cabbage had certain scavenging ability on DPPH free radical, hydroxyl radical superoxide anion, and H₂O₂free radical, but less than V_C’s ability to remove them.The purple cabbage polyphenol had certain ability of restraint on lard and sesame oil oxidation that was lower than V_Cand V_Eespecially at the late stage of lipid oxidation.The polyphenol had the inhibiting effect on Bacillus subtilis, Acetic acid bacteria, Escherichia coli, Saccharomyces cerevisiae.The maximum of antibacterial circle were 13.25, 16.15, 12.45 and 14.65 mm respectively when the polyphenol concentration was 0.5 mg/m L.The purple cabbage polyphenol had the powerful inhibit for Acetic acid bacteria and weak inhibit for Escherichia coli.