温度预处理对柑橘果实活性氧代谢相关酶的影响

以尾张温州蜜柑（Ｃｉｔｒｕｓ　ｕｎｓｈｉｕ　Ｍａｒｃ．）和哈姆林甜橙（Ｃｉｔｒｕｓ　ｓｉｎｅｎｓｉｓ　Ｏｓｂｅｃｋ．）为试材，研究了不同温度预处理对果实呼吸速率、超氧化物歧化酶（ＳＯＤ）活性、过氧化氢酶（ＣＡＴ）活性、过氧化物酶（ＰＯＤ）活性、丙二醛（ＭＤＡ）含量、果皮相对电导率（ＲＥＣ）和木质素含量的影响。结果表明，２０℃预处理 ３ｄ的果实，在贮藏至 １００ ｄ时，呼吸速率、ＭＤＡ含量。果皮 ＲＥＣ均为最低。２０℃预处理果实在贮藏后期 ＳＯＤ与 ＣＡＴ能较好地协同作用清除 Ｏ２－·，果实受自由基伤害程度最小，果实衰老得以延缓。温度预处理引起的ＰＯＤ活性的上升可能与提高果皮木质素含量、加速受损伤油胞的迅速愈合有关，而贮藏后期 ＰＯＤ活性的上升可能与果实的衰老有关。

Effects of Temperature Pre-treatment on the Enzymes Related to the Metabolism of Active Oxygen in Citrus Fruit

Fruit of Satsuma mandarin (Citrus unshiu Marc.) and Hamlin sweet orange(Citrus sinensis Osbeck. ) were used as material for studying the effects of different temperature pre-treatments on fruit respiratory rate, superoxide dismutase (SOD), catalase(CAT) and peroxidase(POD) activity, malondlaldehyde (MDA) content, relative electrical conductivity (REC) and lignin content of pericarp. Results showed the respiratory rate, MDA content, REC of the fruit pre-treated with 20℃ were the lowest ones throughout the whole storage period. The incresed POD activity caused by temperature pre-treatment may be connected with the increase of pericarp lignin content and flavedo cure, while the increased POD activity in late storage peri- od may be involved in the senescence of citrus fruit. It is suggested that the 20℃ pre-treatment allowed SOD and CAT inter- act better to get rid of O2-, thus lessen the level of free- radical injury and postpone fruit senescence.