高氧处理对冬枣货架期间膜脂过氧化和保护酶活性的影响

Effect of Postharvest High-oxygen Treatments on‘Dongzao’Jujube Membrane Lipids Peroxidation and Defensive Enzyme Activities during Shelf-life

研究了在-1^-2℃条件下冬枣果实经流动的21%O2(空气对照)、70%O2(30%N2)、100%O2分别处理7d和15d,在20℃货架期期间测定果实相对电导率、丙二醛(MDA)含量以及保护酶系(SOD、CAT、POD)活性的变化。结果表明,高O2处理可抑制冬枣货架期相对电导率的升高,100%O2处理效果好于70%O2处理。70%O2处理7d对冬枣货架期期间的膜脂过氧化作用没有显著影响,但诱导了SOD、CAT和POD活性的升高,促进冬枣果实在货架期衰老。100%O2处理能抑制冬枣果实货架期膜脂过氧化作用,在货架期期间保持较稳定的SOD和CAT活性,但对POD活性的升高有促进作用。总体来看,100%O2处理15d对减缓冬枣货架期的衰老代谢有较好效果。

The effects of postharvest high-oxygen dehyde （ MDA ） content, and activities of defensive treatments on relative electric conductivity, malondialenzymes （SOD, CAT, POD） in ＇Dongzao＇ jujube and ventilated continuously with air （21% O2）, 70% O2 ＋30%N2 or 100% O2 at -1 to -2℃ for 7 or 15 days, and then placed at 20℃ for the test of shelf-life. The results showed that high-oxygen treatments could inhibit the increase of relative electric conductivity and the treatment with 100% O2 was more effective than that of 70% O2. 70% O2 treatment for 7 d had not positive effects on reducing the MDA contents, but induced the high levels of SOD, CAT and POD activities. The result indicated that 70% O2 postharvest treatment fastened the senescence of jujube fruits during shelf-life. Treatment with 100% O2 for 15 d was the most effective in keeping membrane permeability and maintaining the activities of defensive enzyme during shelf-life.