对菊粉酶产生菌B-3-3发酵条件、酶的分布及酶学特性的研究

经过对pH、摇瓶装量、底物浓度及碳源种类与酶合成之关系进行研究,发现B-3-3菌株在碱性条件,较大通气量,和较高的碳源浓度下产菊粉酶较高,可达21u/ml。当以蔗糖代替菊粉为碳源时,产酶更高。而其它所试糖类较小或没有诱导菊粉酶合成的作用。改进种子液的制作和种子液培养基的成份,大大缩短了酶合成的时间,并提高了酶的产量。 对B-3-3的菊粉酶在胞内外分布进行了研究,结果为胞内酶:胞外酶约为1∶2;pH和温度对酶的活性和稳定性影响较大,其最适pH为6.5,最适温度55℃。在pH6～8的范围内和55℃以下,酶较稳定。

Study on Producing Inulinase Condition Contribution and Characteristics of Inulinase by Strain B-3-3

The relation of inulinase synthesis with pH,concentration of substrate,aerate demandment,variety of carbon resources by strain B-3-3 of Bacillus subtilis was examined. The strain produced inulinase activity up to 21u/ml when it was cultured under alkaline condition, higher concentration of carbon resource and more aeration. Sucrose was able to be used to substitute for inulin as carbon resource for inulinase synthesis,however,other carbonhydrate compounds used in the test didn' t show such effect.The strain B-3-3 produced both intracellular and extracellular inulinase and the ratio of them was about 1 : 2.The stability and the activity of inulinase from the strain B-3-3 were much influenced by pH and temperature. The results of the test show that the optimum pH was 6. 5 and the optimum temperature was 55℃, but the inulinase was relative stable in pH 6-8 and under 55℃.