黑曲霉酸性β-甘露聚糖酶曲盘发酵与粗酶性质研究

用黑曲霉菌株(Aspergillus niger)LW—1进行固态发酵生产酸性β-甘露聚糖酶,其曲盘(大小φ20 cm×4 cm)发酵的最优工艺为:培养基最初料水比为1:1.8,起始pH自然,接种量10%(相对于干物料),曲盘中装料150g(以干料计),通过中间补水和翻曲,32℃培养72 h,最高酶活可达22 250 IU/g(干曲)。对粗酶性质进行研究,结果表明,酶的最适反应温度和pH分别为70℃和3.5,低于60℃、pH5.0～8.0酶稳定,Zn~(2+)、Ca~(2+)、ED- TA对酶有明显的激活作用;Mn~(2+)、Fe~(2+)、pb~(2+)、Sn~(2+)、Fe~(3+)、Cu~(2+)、Al~(3+)、Ag~+对酶有一定的抑制作用。

Study on the Koji Plate Fermentation Process of the Acidic β-Mannanase from Aspergillus niger and Its Partial Properties

The production of acidicβ-mannanase was studied by solid state fermentation with the strain Aspergillus niger LW—1.The optimal koji plate fermentation conditions were as follows,the ratio of water to dry medium is 1.8:1,initial pH natural,inoculum size 10% (related to dry medium),dry medium con- tent 150 g/koji plate.Under these conditions,the acidicβ-mannanase activity reached 22 250 IU/g dry medi- um at 32℃for 72 h by adding water and turning koji.The optimal temperature and pH forβ-mannanase reac- tion were 70℃and 3.5 respectively.The enzyme showed a high stability at pH 5.0～8.0 below 60℃.The activity of enzyme was stimulated by Zn~(2+)、Ca~(2+)、EDTA and inhibited by Mn~(2+),Fe~(2+),Pb~(2+),Sn~(2+),Fe~(3+), Cu~(2+),Al~(3+),Ag~+.