鲜食糯玉米采后糖代谢相关酶活性变化

鲜食糯玉米采后腺苷二磷酸葡萄糖焦磷酸化酶（ADPGPPase）、尿苷二磷酸葡萄糖焦磷酸化酶（UDPGPPase）、束缚态淀粉合成酶（GBSS）、淀粉脱分支酶（DBE）等活性均呈现单峰曲线变化,第1～2天出现峰值然后略有下降;可溶性淀粉合成酶（SSS）活性呈较大幅度上升趋势,活性远高于采收初期;淀粉分支酶（SBE）在第3天出现极高峰值。与20℃贮藏温度相比,采后0℃低温贮藏可增强UDPGPPase活性,促进蔗糖降解;降低SSS和GBSS活性,延缓淀粉合成进程;抑制SBE活性,增强DBE活性,促进直链淀粉生成。

Changes of Enzyme Activities Associated with Carbohydrate Metabolism in Postharvest Fresh Zea mays L.sinensis Kulesh

The activities of UDP-glucose pyrophosphorylase （UDPGPPase）,ADP-glucose pyrophosphorylase （ADPGPPase）,granule-bound starch synthase （GBSS） and starch-debranching enzyme （DBE） in the postharvest fresh waxy corn （Zea mays L. sinensis Kulesh） all showed a single peak curve,which reached the peak value on the first or the second day and then declined slightly. The activity of soluble starch synthase （SSS） increased significantly,while the activity of starch branching enzyme （SBE） appeared the peak value on the third day. Compared with the condition of 20 ℃,the activity of UDPGPPase increased to promote the sucrose degradation,the activities of SSS and GBSS reduced to slow down the process of starch synthesis,the activity of SBE was restrained while DBE strengthened to promote the amylose synthesis when stored at 0 ℃.