以香蕉为试材,研究采后不同温度(20、4℃)贮藏对果实的呼吸作用、糖代谢及其相关酶活性变化的影响.结果表明:20℃贮藏早期(0～8 d),果实呼吸作用平缓上升,SPS,NI和AI酶活性较低,蔗糖、果糖和葡萄糖含量较少;随着果实进入快速软化阶段(8～13 d),3种酶活性与蔗糖含量分别在第13天和第12天达到峰值,然后急剧下降,变化趋势类似于CO2释放量.而果糖和葡萄糖含量在20℃贮藏过程中持续上升,SS活性无明显变化.相比之下,4℃贮藏可明显抑制果实的呼吸作用,CO2含量先降低后缓慢增加,SPS、NI和AI酶活性和搪含量上升缓慢,SS活性下降.由此,低温贮藏可明显抑制香蕉体内碳素代谢,降低代谢酶活性和糖分积累速度,有利于提高果实品质,延缓贮藏时间.%The effect of different temperatures (20 and 4 ℃ )on respiration characteristic, sugar content and sugarmetabolizing enzyme activities from banana fruits was studied during storage. In the early 0～8 d, fruit respiration gradually increased. Moreover, there were all low in the activities of invertase (Al), neutral invertase (NI), sucrose synthase(SS), sucrose phosphate synthase (SPS) and the contents of sucrose, fructose and glucose. The peak values of the three enzymes and the sucrose content were in the 13th and 12th during softening stage 8～13 d, respectively, and then rapidly decreased. This tendency was consistent with the change of CO2. However, the fructose and glucose increased slowly, and SS activity did not change significantly during the total process of postharvest. In 4 ℃ storage, CO2 respiration was inhibited, first decreased and then increased slowly. The activities of SPS, NI, and Al and the content of sugar gradually went up. But SS activity declined during the fruit storage. So low temperature storage in vitro can significantly inhibit the metabolism of carbohydrate the banana, reduce the activity of the enzymes and the speed of sugar accumulation. It affects on fruit ripening and quality, and is benefit for a long-term storage of fruits.
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