生鲜葱白自身酶解条件的研究

Study on the Self Enzymolysis Conditions of Fistular Onion Stalk

目的:通过对生鲜葱白自身酶解条件进行初步研究,为进一步研究葱白中的酶活性提供依据。方法:利用丙酮酸与2,4-二硝基苯肼-氢氧化钠系统发生显色反应原理,采用分光光度法测定丙酮酸的生成量来推算酶活力,同时根据丙酮酸的生成量间接反映含硫化合物的生成量,考察不同温度、pH、金属离子、时间以及不同灭活方式对酶解的影响。结果:温度在25～55℃之间酶活性较高,超过65℃后急剧下降;pH在6～8之间时,酶活性受到的影响比较小;Fe^(3+)、Cu^(2+)这两种金属离子对鲜葱白中酶活性有一定抑制作用,而Ca^(2+)、Zn^(2+)对葱白中酶的活性影响不是很大;酶促反应进行迅速,30min内完成;对比三种灭活方式的影响是微波>有机溶剂>高温。结论:葱白中酶有着其最适宜的反应温度、pH以及离子活性中心。

To provide the basis for further study on the enzyme activity in fistular onion stalk through preliminary study on the enzymolysis conditions. Method： Color reaction between pyruvate and 2,4-dinitrophenylhydrazine-sodium hydroxide system was applied to evaluate the enzyme activity through the determination of pyruvate by spectrophotometry, and the amount of sulfur compounds could be shown by the pymvate amount. The influences of different temperature, pH, metal ions, time and inactivation methods on the enzymolysis were studied. Result： The enzyme activity was highest when temperature was between 25-55℃ , and decreased rapidly when the temperature was above 65℃. There was little change in the enzyme activity when pH value was between 6 and g. Fe^3＋ and Cu^2 ＋ could inhibit the enzyme activity in fistular onion stalk, while Ca^2＋ and Zn^2＋ had little effect. Enzymatic reaction was very quickly completed within 30 min. The effect order of the three inactivation methods was microwave 〉 organic solvents 〉 high temperature. Conclusion： Alliinase in the fistular onion stalk should be with the suitable temperature, pH value and ionic activity center.