贮藏温度对白菜叶片SOD、POD活性及MDA含量的影响

[目的]研究白菜叶片在不同贮藏温度下超氧化物歧化酶(SOD)、过氧化物酶(POD)活性及丙二醛(MDA)含量的变化特点.[方法]以白菜品种紫衣、百慕田和947-5s为供试材料,将白菜叶片在不同温度下贮藏不同时间(4℃下贮藏0,3,5,8和10 d;-40,-80℃下贮藏0,12,24,48和72 d),测定SOD、POD活性及MDA含量.[结果]不同品种叶片的SOD活性明显不同.4℃贮藏条件下,紫衣、百慕田和947-5s SOD活性表现相同的变化趋势,即冷藏0~5 d和8~10 d活性变化不大,冷藏5~8 d SOD活性明显增大,8d时SOD活性较5d时分别提高了62.28%,74.83%和61.96%;-40,-80℃两种冻藏温度下,SOD活性均表现为升高-降低-上升的变化趋势.不同品种叶片的POD活性明显不同.4℃贮藏条件下,紫衣、百慕田和947-5s POD活性都表现先下降再上升趋势,在冷藏第3天降到最低值,较0d分别下降了42.64%,18.16%和11.4%,3~10 d POD活性逐渐上升,10d时的POD活性分别为0d的1.10,1.49和2.14倍;在两种冻藏温度下3个品种POD活性都呈现下降-上升-下降趋势,且品种间POD活性变化较大.3个白菜品种鲜叶片的MDA含量明显不同.4℃贮藏条件下,947-5s和百慕田MDA含量呈逐渐升高趋势,紫衣则为逐渐降低趋势.在-40,-80℃条件下,紫衣MDA含量都呈现下降-上升-下降-上升的波浪式趋势;-40℃条件下947-5s和百慕田MDA含量呈现上升-下降-上升相同趋势;-80℃条件下947-5s MDA含量呈现升高-降低-上升-降低趋势,而百慕田MDA含量无明显变化.[结论]3个白菜品种鲜叶片SOD、POD活性和MDA含量各不相同.3个白菜品种叶片只有SOD的活性在4℃冷藏0~5 d时有平稳期,而POD活性及MDA含量在冷、冻藏条件下都会随着时间延长而变化.

Effect of Freshness Protection Package on Storage and Preservation of Chinese Cabbage

The effect of freshness protection package on Chinese cabbage placed in the self-made shelf in ventilated storage was investigated, and the physiological-qual-ity indexes change were determined during the storage period. The results showed that the losses of weight and vitamin C were significantly reduced. The accumula-tion of crude fiber was effectively inhibited. But protein content was maintained at a low level and the rotting more serious of Chinese cabbage at the end of the stor-age packaged with the fresh keeping bags.