摘要
以甜菜品种淮阴11号为材料。测定了在不同贮藏条件下甜菜块根呼吸强度、呼吸代谢的酶的活性及呼吸抑制剂的作用。试验结果表明,在温度处理15天以后,冻化贮藏的甜菜块根呼吸强度明显高于其它温度处理的甜菜。糖酵解和已糖磷酸途径抑制剂对呼吸强度的抑制百分比随贮藏时间的延长而加强,而三羧酸代谢途径的抑制剂(丙二酸)对呼吸的抑制程度较低且无明显变化。葡萄糖-6-磷酸脱氢酶活性在甜菜贮藏过程中逐渐加强,尤其是冻化贮藏的甜菜,其活性也明显高于琥珀酸脱氢酶活性。以上结果说明甜菜块根贮藏过程中,呼吸代谢既可通过糖酵解-三羧酸途径,也可通过己糖磷酸途径,且后者的作用随贮藏时间的延长而逐渐加强。另外,呼吸末端氧化是通过细胞色素氧化酶和过氧化氢酶,而贮藏后期多酚氧化酶活力则有明显的增强。
Repiration is one of the most important causes that led to the sugar loss during the storage of sugarbcet roots. To reduce the sugar loss, the changes of the respiratory metabolism during the storage of sugarbcct roots were invcstigated, with the species of Huaiying No. 11, by measuring the effects of different respiratory inhibitors on the respiration of sugarbeet roots and analyzing the changes of some enzymes activities related to metabolism of sugar. The results indicated that, after 15 days of temperature treatment, the respiration rate of the freeze-thawing sugarbeet roots rose significantly and was much higher than those of other treatments. The inhibition percent of Na_3PO_4, NaAsO_2 and Iodoacetic acid on respiration rate of sugarbeet roots increased with the time of storage, but the effect of malonate on respiration was lower. The activity of glucose-6-phosphate dehydrogenase increased with the storage of sugarbeet, especially freeze-thawing sugarbeet, and was markedly higher than that of succinate dehydrogenase. These results suggested that, during the storage of sugarbcet, the decomposition of sugar proceeded not only through the EMP-TCA pathway, but also through the HMP pathway, furthermore, the activity of HMP pathway gradually enhanced as the storage time passed by. In addition, the terminal oxidation of sugar in the early stage of storage was mainly through cytochrome oxidase and catalasc, but in the late stage, the activity of polyphenol oxidase significantly increased.
出处
《江苏农学院学报》
CSCD
1990年第3期43-48,共6页
Jiangsu Agricultural Research
关键词
甜菜
块根
贮藏
呼吸代谢
sugarbeet root
respiratory inhibitor
respiration pathway
terminal oxidase
