β-葡萄糖苷酶产生菌的筛选及其所产纤维素酶酶系组成分析

Screening of β-glucosidase producing strain and analysis of cellulase composition

从木霉属、曲霉属、担子菌等17种试验菌株中筛选出一株产β-葡萄糖苷酶活性较高的黑曲霉A.niger-nl-1。该菌株在适宜的培养条件下,β-葡萄糖苷酶的最高活力达到4.7U/mL,适宜的产酶周期为4d。制备的β-葡萄糖苷酶最适反应温度为55℃、最适反应pH为5.0。该菌株除能产生β-葡萄糖苷酶外,还能产生内切葡聚糖酶和外切葡聚糖酶,滤纸酶活达到0.62IU/mL。

The highest β-glucosidase producing strain A. niger-nl-1 was selected from the 17 strains of Trichoderma, Basidiomycetes and Aspergillus. The higher activity of β-gluoosidase, up to 4.7 U/mL, was synthesized by A. niger-nl-1. The period of β-glucosidase production was 4 days. The optimal enzymatic reaction temperature and pH for β-glucosidase were 55℃ and 5.0, respectively. The enzyme showed better heat-resistant ability and acid-resistant ability. Besides β-glucosidase, the higher exo-glueanases and endo-glucanases were synthesized by the strain during the same fermentation. The filter paper activity （FPA） reached 0.62 IU/mL.