通过七叶苷平板法从腐殖质土壤中筛选得到高产β-葡萄糖苷酶的2个菌株(H2和H5),并利用单因素法对这2个菌株的产酶条件进行了优化.经形态学特征初步鉴定,菌株H2和H5均为黑曲霉(Aspergillus niger).H2的最优发酵条件为:以蔗糖为碳源,以硫酸铵+尿素(1:1)为氮源,培养5 d,培养温度28 ℃,初始pH 4.0.H5的最优发酵条件为:以红糖为碳源,以硫酸铵+硝酸铵(1:1)为氮源,培养5 d,培养温度28 ℃,初始pH 4.5.在优化的各因素中,以培养温度对菌株H2和H5所产β-葡萄糖苷酶活力的影响最大.%Two β-glucosidase-highly-producing strains H2and H5were isolated and screened out from humus soil by adop-ting aesculin plate method, and their fermentation conditions for the high-efficient production of β-glucosidase were optimized through single-factor experiments. Both H2and H5were preliminarily identified as Aspergillus niger through morphological observa-tion. The optimum fermentation conditions for H2were obtained as follows:using sucrose as carbon source,using ammonium sul-fate plus urea(1:1)as nitrogen source, culture for 5 days at 28 ℃,initial pH-value 4.0. The optimum fermentation conditions for H5were: using brown sugar as carbon source,using ammonium sulfate plus ammonium nitrate(1:1)as nitrogen source,cul-ture for 5 days at 28℃,initial pH-value 4.5. Among the optimized various factors,culture temperature had the greatest influence on the activity of β-glucosidase produced by the above 2 strains.
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