不同烘烤条件下烟叶淀粉降解酶活性变化

The Activity Changes of Starch Degradation Enzymes in Tobacco Leaves under Different Curing Condition

以烤烟品种红花大金元和K32 6的中部叶为材料,研究了烘烤过程中烟叶淀粉酶和淀粉磷酸化酶活性变化及烘烤条件对淀粉酶和淀粉磷酸化酶活性的影响。结果表明:烘烤过程中,烟叶淀粉酶活性出现2次高峰,分别处于烘烤的变黄中期和定色前期;鲜烟叶中淀粉磷酸化酶活性较高,随着烘烤过程的推进,至2 4h达第1次高峰,之后降低,4 8h时出现低谷,随后红花大金元于6 0h达第2次高峰,而K32 6于72h达第2次高峰。在整个烘烤过程中,采用低温低湿变黄,慢速升温定色的烘烤条件,烟叶内淀粉酶和淀粉磷酸化酶活性较高,有利于烟叶淀粉的降解。

The effects of curing condition on the activity of amylase and starch phosphorylase and the changes of the activity of amylase and starch phosphorylase in tobacco leaves during flue-curing were studied by using the flue-cured tobacco cv. HD and K326 as experimental material. The results indicated that two peaks of amylase activity appeared at middle stage of yellowing and early stage of flxing-color during curing, respectively. The activity of starch phosphorylase was relatively higher in fresh leaves. With the proceeding of curing, the activity of starch phosphorylase reached its first peak at the 24th hour, followed by a valley at the 48th hour, and then,that of HD reached the second peak at 60h and that of K326 reached the second peak at the 72th hour. During the whole process of flue-curing, the activity of amylase and starch phosphorylase was relatively high and starch degradation was quick under the curing condition of tobacco leaves yellowing by lower temperature and humidity and heating and fixing-color at slow speed.