Influence of gamma irradiation on microbial load and antioxidative characteristics of Polygoni Multiflori Radix

The antioxidative effects and major antioxidant components of 0 kGy, 5 kGy, 10 kGy and 15 kGy irradiated POMU samples were also examined. Our results confirmed that 5 kGy irradiated POMU had both the highest antioxidative activity and lowest value in IC50 of DPPH radical-scavenging activity. The content of total phenols had no statistically significant changes. Therefore gamma irradiation at 5 kGy could be a potential method for decontaminate the microbial load of POMU to prolong shelf life and to improve hygienic quality.