[关键词]
[摘要]
采用超微粉碎法、超声波法、反复冻融-研磨法,对冠突散囊菌子囊孢子进行破壁处理,探讨不同破壁方法对孢子粗多糖抗氧化活性的影响。结果表明,破壁率由高至低依次为反复冻融-研磨法(93.73%)、超微粉碎法(82.27%)、超声波法(66.54%),粗多糖的提取率分别为2.18%、2.06%、1.84%,均显著高于未破壁孢子(1.15%)。抗氧化试验表明,3种破壁孢子粗多糖均具一定抗氧化活性,且与质量浓度间存在着显著量效关系。以超微粉碎法破壁孢子粗多糖活性为最强,在其质量浓度为2.50 mg/mL时,对DPPH、OH、ABTS+三种自由基清除能力分别为89.13%、95.22%、80.26%,铁离子还原能力为0.78。反复冻融-研磨组和超声波组粗多糖活性低于超微粉碎组,说明此型号粉碎机低温下的高速剪切作用对冠突散囊菌子囊孢子多糖分子造成的损伤低于超声空化作用与反复冻融,适宜用于冠突散囊菌子囊孢子的破壁。
[Key word]
[Abstract]
The ultrafine grinding method, ultrasonic method, and repeated freeze-thaw and grinding method were used to break the wall of Eurotium cristatum ascospore. The effects of these wall-breaking methods on the antioxidant activity of crude polysaccharides from the ascospore were investigated. The results showed that the wall-breaking rate decreased in the order of the repeated freeze-thaw and grinding method (93.73%), the ultrafine grinding method (82.27%), and the ultrasonic method (66.54%), with their corresponding extraction rates for crude polysaccharides as 2.18%, 2.06% and 1.84%, respectively, all of which were significantly higher than the extraction rate for the unbroken spores (1.15%). The results of the antioxidant tests showed that the crude polysaccharides obtained from the three types of broken ascospores exhibited a certain degree of anti-oxidative activity (which had a significant relationship with the mass concentration: dose-dependent effect). The crude polysaccharide obtained from the broken ascospores by ultrafine grinding showed the highest antioxidant activity, and at a mass concentration of 2.50 mg/mL, its capacity to scavenge DPPH, ABTS+ and ?OH radicals was 89.13%, 95.22% and 80.26% respectively with the reducing capacity for iron ions being 0.78. The antioxidant activities of the crude polysaccharides obtained by the repeated freeze-thaw and grinding method and the ultrasonic method were lower than that obtained by the ultrafine grinding method. These results indicated that the damage on the polysaccharide molecules of Eurotium cristatum ascospore due to the high-speed shear generated by this type of crusher at low temperature was less than that caused by the ultrasonic cavitation and repeated freeze-thaw process. Thus, the ultrafine grinding method is suitable for breaking the cell wall of Eurotium cristatum ascospores.
[中图分类号]
[基金项目]
黑茶金花湖南省重点实验室项目(2016TP1022);湖南省重点研发计划资助项目(2018NK2036);益阳市科技计划项目(2017YZ04)