黑曲霉NHF5产单宁酶的发酵优化及转录组学分析  

Medium Optimization and Transcriptomic Analysis of Tannase Production by Aspergillus niger NHF5

作　　者：刘媛媛 卢海强[1] 李家骏 王雪晴 谷新晰[1] LIU Yuanyuan;LU Haiqian;LI Jiajun;WANG Xueqing;GU Xinxi(College of Food Science and Technology,Hebei Agricultural University,Baoding 071001,China)

机构地区：[1]河北农业大学食品科技学院,河北保定071001

出　　处：《食品科技》2024年第8期30-38,共9页Food Science and Technology

基　　金：国家自然基金项目(31901631);河北省高等教育教学改革研究与实践项目(2023GJJG115);河北省实验教学和教学实验室建设研究项目(2024-40);河北农业大学校级教学研究专题项目(2021sz010)。

摘　　要：以产高活性单宁酶的黑曲霉NHF5为发酵菌株,利用响应面分析法对其产酶培养基进行优化,最终确定3因素的最佳种类及终浓度如下所示:葡萄糖1.5%(w/V)、硫酸铵1.25%(w/V)、单宁酸2.5%(w/V),粗酶液酶活可达192.85 U/mL,是优化前酶活力的4.4倍。为进一步探究黑曲霉NHF5在发酵培养基中基因表达规律,经转录组学分析发现共有111个差异表达基因,含显著上调基因36个,含显著下调基因75个。经GO富集分析发现,差异表达基因主要富集到分子功能、细胞组分和生物过程等GO条件;通过KEGG通路富集显示,36个显著上调基因参与了7个代谢通路。在这些差异表达基因中一共有阿魏酰酯酶、葡萄糖甲醇胆碱氧化还原酶、单宁酶、O-甲基转移酶等16个碳水化合物活性酶基因表达,其中碳水化合物酯酶和糖苷水解酶表达量最为丰富,两者均占43.75%。研究结果不仅为单宁酶的高效生产提供了技术指导,也为菌株合成单宁酶的内在机制进行了一定的理论探索。Aspergillus niger NHF5,which produced high tannase activity,was used as fermentation strain,response surface methodology was used to optimize its enzyme-producing medium.Finally,the optimal species and final concentrations of the three factors were determined as follow:glucose 1.5%,ammonium sulfate 1.25%,and tannic acid 2.5%.At this time,the enzyme activity of crude enzyme solution reached 192.85 U/mL,which was 4.4 times more active than the enzyme before optimization.In order to investigate the gene expression of Aspergillus niger NHF5 in fermentation medium,A total of 111 differentially expressed genes were identified by transcriptomic analysis,including 36 significantly up-regulated genes and 75 significantly down-regulated genes.GO enrichment analysis showed that the differentially expressed genes were mainly enriched in GO items such as molecular function,cell components,and biological processes.The enrichment of the KEGG pathway showed that only 7 of the 36 significantly up-regulated genes were involved in the metabolic pathway.Among these differentially expressed genes,16 carbohydrate-active enzymes were expressed,including ferulate esterase,glucose methanol choline oxidoreductase,tannase O-methyltransferase,and so on.The expression of carbohydrate esterase and glycoside hydrolase were the most abundant,accounting for 43.75%.The results not only provide technical guidance for the efficient production of tannase,but also provide theoretical exploration for the internal mechanism of tannase synthesis in strains.

关 键 词：黑曲霉 单宁酶 响应面 转录组 碳水化合物活性酶 

分 类 号：TS201.3[轻工技术与工程—食品科学]