中文摘要：

研究了不同酶反应缓冲体系、pH值、氯离子浓度以及嚼唑哒嗪对5龄2日粘虫PseudaletiaseparataWalker中肠α-淀粉酶活性的影响。结果表明，乙酸-乙酸钠缓冲体系（pH5．8）和磷酸氢二钠-磷酸二氢钠缓冲体系（pH8．0）有利于增强α-淀粉酶活性，比活力最高分别达到4．49和4．97。在乙酸-乙酸钠缓冲体系（pH5．8）中，5、10、20、40和80mmol／L氯离子浓度引起α-淀粉酶活性呈现先减弱后增强的变化规律，而在磷酸氢二钠-磷酸二氢钠缓冲体系（pH8．0）中仅呈现减弱的趋势。1．4mmol／L嚼唑哒嗪对α-淀粉酶活性的抑制率可达70％，但抑制程度随着反应体系中蛋白含量的增加而逐渐降低。

英文摘要：

The effects of different enzymatic buffers, pH value, chloridion, and oxadiazolyl pyridazinone on the midgut α-amylase activity in 5th-instar 2nd-day larvae of Pseudaletia separata Walker were assayed. The results showed that sodium acetate buffer （pH 5.8） and phosphate buffer （pH 8.0） were most beneficial to α-amylase activity in their buffer series with different pH value, with the maximal activity as high as 4.49 and 4.97 U respectively. The activities against 5, 10, 20, 40, 80 mmol/L chloridion showed first decreasing and then increasing in sodium acetate buffer （pH 5.8 ）, whereas they showed only gradually decreasing in phosphate buffer （pH 8.0）. Inhibition of 1.4 mmol/L oxadiazolyl pyridazinone against α-amylase activity was as high as 70 percent, and thereafter gradually decreased with the increase of α-amylase protein.