不同温度下后熟香蕉果实果皮生理与颜色变化

Effects of Temperature on Peel Colour and Physiological Changes of Banana Fruits during Ripening

香蕉果实经乙烯利处理后,比较20℃和30℃下后熟期间的果皮色泽、淀粉转化及几种细胞壁降解相关酶活性的变化。在20℃下,香蕉果实能正常褪绿和软化,而30℃高温则明显抑制了褪绿转黄,加速了果皮软化。与20℃后熟比较,30℃促进了香蕉果皮中淀粉向可溶性糖的转化,提高了多聚半乳糖醛酸酶、纤维素酶、果胶甲酯酶等的活性。讨论了香蕉果皮可溶性糖含量与青皮熟形成之间的可能关系。

Effects of temperature on peel color and physiological changes of banana fruits during ripening were investigated. Fruits were dipped in 0.1% ethephon for 1 min, and then ripened at 20℃ and 30℃, respectively. The changes in peel eolour, contents of starch and soluble sugar and activities of cell wall degradation-related enzymes, such as polygalaturonase （PG）, pectinmethylesterase （PME） and cellulase, were measured. The results showed that banana fruits degreened and softened normally during ripening at 20℃, while ripening at 30℃, the fruits hastened the softening and inhibited the degreening of the peel, resulting in the development of a pale greenish yellow colour. Furthermore, compared with the fruits ripened at 20℃, the starch in fruits ripened at 30℃ enhanced the conversion to soluble sugar, and the activities of PG, PME and cellulase were increased. It was suggested that there were relationship between green-ripe banana fruit at high temperature and soluble sugar in peel, but irrelevant to softening-related physiological changes.