热激减轻柿果冷害及其与脂氧合酶的关系

为研究采后柿果实冷害发生机理,探讨热激延缓采后柿果冷害的技术措施,以扁花柿果为试材,研究了经48℃热空气处理3h后,在1℃下冷藏时,热激对柿果冷害、脂氧合酶活性和膜脂脂肪酸含量的影响。结果表明,热激延缓了脂氧合酶活性的上升,其棕榈酸和硬脂酸的相对含量低于对照,而亚油酸和亚麻酸相对含量反而高于对照,并降低柿果冷害指数,但对油酸相对含量则无明显影响。这表明,热激减轻柿果冷害可能与抑制脂氧合酶活性和提高果实亚油酸和亚麻酸相对含量有关。

Relationship between heat shock alleviating chilling injury and lipoxygenase of persimmon fruit

In order to study the mechanism of chilling injury and to determine the efficacy of hot shock in delaying fruit chilling injury, the persimmon fruit were treated in hot air at 48℃ for 3 hours after harvest, then stored at 1℃. Chilling injury index, lipoxygenase activity and fatty acid relative content of persimmon fruit were investigated. Results showed that heat shock retarded the activity of lipoxygenase. The chilling injury index and the relative content of palmitic acid and stearic acid of persimmon fruit by heat shock was significantly lower than that of control. While the relative content of linoleic acid and linolenic acid in heat shock persimmon fruit were significantly higher than that of control fruit. But there was no significantly difference in oleic acid relative content. These results indicated that heat shock in persimmon could delay chilling injury through inhibition of lipoxygenase activity and elevation of linoleic acid and linolenic acid relative content.