产菊糖酶菌株的选育及特性研究

Study on Screening and Characteristic of Strains of Producing Inulinase

从发霉的菊芋中分离得到菌种,用平板透明圈法筛选出2株产菊糖酶活力较高的菌株H10和Q12。经菌种形态学观察和鉴定,确定菌株H10为黑曲霉,Q12为青霉,并对其进行了发酵条件的研究。两菌株产酶的环境条件有一定差异,黑曲霉以基质含2%菊糖,初始pH值7.0,装量50mL(250mL的三角瓶中),温度28℃,转速240r/min为摇瓶发酵最适条件;青霉以基质含3%菊糖,初始pH值6.0,装量50mL(250mL的三角瓶中),温度30℃,转速240r/min为摇瓶发酵最适条件。黑曲霉和青霉产酶分别在120h和96h时达到高峰。

Two inulinase producing stiains, H10 and Q12, were screened by the clarity circle method on the plate, isolated from the moldy Jerusalem artichoke. Stiains H10 and Q12 were observed and identified as Aspergillus niger and Penicilliam sp. by the morphology of the stiains, the the environmental conditions of fermentation were investigated. Aspergillus niger shows optimum inulinase production with 2%inulin, initial pH7.0, 28 ℃ and aeration demand of 50 mL/250 mL, agitation speed 240 r/min; 3%inulin, initial pH6.0, 30 ℃ and aeration demand of 50 mL/250 mL, agitation speed 240 r/min are optimum conditions for Penicilliam sp. Aspergillus niger and Penicillium sp. give maximal enzyme activity at 120 h and 96 h respectively.