Abstract: To evaluate the effect of ⁶⁰Co-γ ray and electron beam irradiation sterilization on the quality of pueraria extract, samples are treated with ⁶⁰Co-γ ray irradiation(0, 2.8, 5.7, 8.3, and 10.6 kGy) and electron beam irradiation(0, 2.4, 5.1, 7.7, and 10.3 kGy) to investigate the microbe quantity, antioxidant activity and fingerprint. The result showed that both ⁶⁰Co-γ ray and electron beam irradiation could effectively reduce the total aerobic bacteria count, the total yeast and mold count in pueraria extract. With the increase of absorbed dose, the inhibitory effect was enhancedand. The pueraria extract treated by the two kinds of irradiation methods both reached the microbial limits standard stipulated in the Chinese pharmacopoeia, and the total aerobic bacteria count is 10³ CFU·g^-1 and the total yeast and mold count is 10² CFU·g^-1, when the absorbed dose of ⁶⁰Co-γ ray and electron beam irradiation were 5.7 kGy and 5.1 kGy, respectively. While the absorbed dose were 8.3 kGy and 7.7 kGy, respectively, the total aerobic bacteria count and the total yeast and mold count were both reduced to below 10 CFU·g^-1. In addition, the escherichia coli and salmonella were not detected. Neither of the two irradiation methods showed significant effects on DPPH free radical (DPPH·) scavenging rate, hydroxyl free radical(·OH) scavenging rate and total reducing ability of pueraria extract(P>0.05). The similarity of characteristic peak of pueraria extract irradiated by ⁶⁰Co-γ ray and electron beam with different doses reaches 1.0, and the RSD of relative retention time was less than 0.5%, which shows that there were no significant difference in the influence of the two irradiation methods on the fingerprint of pueraria extract. In conclusion, ⁶⁰Co-γ ray and electron beam irradiation both showed inhibitory effect on the microorganisms of pueraria extract, no significant effect on the antioxidant activity and fingerprint of pueraria extract, and could not affect the efficacy and quality stability of pueraria extract. This research provides scientific reference for the rational application of the two irradiation sterilization techniques, especially electron beam irradiation sterilization utilization in the Chinese medicinal materials, such as decoction pieces and proprietary Chinese medicine of Kudzuvine Root.

Key words: pueraria extract, ⁶⁰Co-γ ray, electron beam, irradiation sterilization, antioxidant activity, fingerprint

摘要： 为评价⁶⁰Co-γ射线和电子束辐照灭菌对葛根提取物品质的影响效应及其差异性,采用不同剂量的⁶⁰Co-γ射线(0、2.8、5.7、8.3、10.6 kGy)和电子束(0、2.4、5.1、7.7、10.3 kGy)辐照处理葛根提取物,研究辐照对其微生物总数、抗氧化活性及指纹图谱的影响。结果表明,⁶⁰Co-γ射线和电子束辐照均能有效降低葛根提取物中需氧菌总数、霉菌和酵母菌总数,随着吸收剂量增大,抑制作用增强。⁶⁰Co-γ射线和电子束辐照吸收剂量分别为5.7 kGy和5.1 kGy时,葛根提取物均达到《中国药典》所规定的微生物限度标准(需氧菌总数为10³ CFU·g^-1、霉菌和酵母菌总数为10² CFU·g^-1);吸收剂量分别为5.7 kGy和7.7 kGy时,需氧菌总数、霉菌和酵母菌总数均降至10 CFU·g^-1以下。此外,大肠埃希氏菌(Escherichia coli)与沙门氏菌(Salmonella)均未检出。2种辐照方式均对葛根提取物的DPPH自由基(DPPH·)清除率、羟自由基(·OH)清除率以及总还原能力无显著影响(P>0.05)。不同剂量⁶⁰Co-γ射线和电子束辐照处理葛根提取物特征峰的相似度达到1.0,且相对保留时间的相对标准差(RSD)均小于0.5%,表明2种辐照方式对葛根提取物指纹图谱均无显著影响(P>0.05)。综上所述,⁶⁰Co-γ射线和电子束辐照对葛根提取物微生物具有较强的抑制作用,2种辐照方式均不会对葛根提取物的抗氧化活性及指纹图谱产生显著影响,不影响葛根提取物的有效性及质量稳定性。该研究为2种辐照技术,特别是电子束辐照在葛根药材、饮片及其中成药制剂灭菌中的合理应用提供了科学参考。

关键词: 葛根提取物, ⁶⁰Co-γ射线, 电子束, 辐照灭菌, 抗氧化活性, 指纹图谱