黑曲霉利用五倍子生料固体发酵产单宁酶优化发酵条件研究

Optimization of the production of tannase by Aspergillus niger solid-state fermentation using gall nut

单宁酶全称是单宁酯酰水解酶(Tannase,EC3.1.1.20),它可以水解没食子酸单宁中的酯键和缩酚羧键,生成没食子酸和葡萄糖。主要来源于微生物,存在于细胞内和细胞外,目前研究得较多较为深入的是青霉和黑曲霉。本实验对五倍子生料固体发酵产单宁酶进行了研究,发酵条件的单因素优化后得到:初始水分含量80%,接种量1%,20%五倍子,温度30℃为最佳产酶条件。在此基础上,利用正交实验对显著影响产单宁酶的培养基及培养条件因素进行优化,得到固体发酵黑曲霉诱变菌株最佳产单宁酶条件为:湿度80%、接种量1%、发酵温度33℃、五倍子含量15%。其中温度对黑曲霉产单宁酶酶活性的影响是显著的,并测得在此最佳发酵条件下产单宁酶活性达57.32U/gds。

The systematic name of Tannase is tannin acylhydrolase(Tannase,the EC 3.1.1.20);it can hydrolyses the ester and depside bonds of gallotannis and gallic acid esters to form glucose and gallic acid.Tannase was mainly produced by microbiology,existing inside and outside of the cell.Penicillium and Aspergillus Niger were mostly studied.This experiment was focused on optimizing fermentation conditions by Aspergillus Niger in solid-state fermentation using gall nuts as substrate.The initial moisture was 80 %,the inoculum 1% and the 30 C was the best conditions by the single factor optimization experiment.Furthermore,orthogonal optimization of the medium and the culture was performed and the best conditions of producing tannase by solid fermentation were:the initial moisture content 80 %,the inoculum 1%,the temperature 33℃ and the gall nuts 15%.Among them,the temperature had a remarkable effect on Tannase activities.The activity of Tannase was up to 57.32U/gds under the above condition.