摘要
散囊菌属真菌是我国砖茶加工中的重要微生物,对茯砖茶的品质、风味和生理功能的形成起到关键的作用。应用鉴别培养基平板检测、茶叶固体发酵和胞外分泌蛋白组分析相结合,本文研究18株散囊菌在DG18培养基中的大分子水解酶活性;以及发酵条件对菌株LP-7胞外分泌蛋白产量的影响和胞外蛋白的组成。平板检测结果表明:在本研究的试验条件下,18个菌株中有8个菌株表现单宁酶活性,10个菌株表现淀粉酶活性,6个菌株表现脂肪酶活性,10个菌株表现纤维素酶活性,9个菌株表现蛋白酶活性;菌株LP-7同时检测到5种胞外水解酶活性;LP-8、FZ-3和QL-2等3个菌株同时检测到4种水解酶活性;而LP-5、LP-6、FZ-1、FZ-2、FZ-4和QL-1 6个菌株同时检测到3种水解酶活性。采用绿茶固体发酵,茶叶含水量为80%,发酵时间为21d,对发酵茶叶中蛋白质产量有明显的促进作用。对菌株LP-7发酵茶叶后的胞外分泌蛋白组进行初步分析,成功鉴定出10个胞外蛋白,其中7个是酶蛋白,分别是α-L-阿拉伯糖甘酶、铜锌-超氧化物歧化酶、单宁酶、脂肪酶、阿魏酸酯酶、芳香族化合物双加氧酶、糖苷水解酶等。在干燥条件下,散囊菌能够分泌丰富的胞外蛋白(酶),这为解释散囊菌在茶叶发酵过程中的酶学机制和功能提供了理论依据。
Eurotium spp. are the dominant microbes during the processing of brick tea and play a key role in the formation of quality, flavor and physiological functions of Fuzhuan Tea. By agar plate tests, eighteen Eurotium strains were examined for their ability to produce extracellular macromolecular hydrolases. The results demonstrated that there were eight strains showing positive activity of tannase, ten strains showing amylase activity, six strains lipase activity, ten strains cellulase activity and nine strains protease activity. The enzyme tests indicated that strain LP-7 produced all five kinds of the hydrolases, strains LP-8, FZ-3 and QL-2 produced four kinds of the enzymes, while strains LP-5, LP-6, FZ-1, FZ-2, FZ-4 and QL-1 produced three kinds of the enzymes. The effects of different solid-state fermentation conditions on secreted protein production of strain LP-7 were studied. Green tea 10g with moisture content of 80%, inoculated with lmL of conidial suspension （5.0-6.0×10-7spores/mL） of Eurotium sp strain LP-7 and incubated at 28℃ for 21 days showed obvious effects of promoting the protein production of fermented tea. The extracellular proteins of fermented tea using strain LP-7 as inoculum were separated by two-dimensional gel electrophoresis and identified by MOLDI-TOF-TOF. A total of ten extracellular proteins were identified, including seven enzyme proteins, such as arabinoxylan, superoxide dismutase [Cu-Zn], tannase, cellulose-binding GDSL lipase, feruloyl esterase, aromatic compound dioxygenase, and glycoside hydrolase enzyme. Under dry condition, Eurotium spp. can produce abundant extracellular proteins, which provides a theoretical basis for the explanation of the mechanism and function of Eurotium enzymes in fermentation of tea.
作者
杨金梅
严蒸蒸
陈佳佳
杨民和
YANG Jin-Mei YAN Zheng-Zheng CHEN Jia-Jia YANG Min-He(College of Life Sciences, Fujian Normal University, Fuzhou, Fujian 350108, China Engineering Research Center of Industrial Microbiology, Ministry of Education, Fujian Normal University, Fuzhou, Fujian 350108, China)
出处
《菌物学报》
CAS
CSCD
北大核心
2017年第6期691-704,共14页
Mycosystema
基金
福建省科技厅重点项目(2012N0013)
福建省自然科学基金(2012J01122)~~
关键词
散囊菌属
胞外水解酶
分泌蛋白
平板检测
蛋白组分析
Eurotium, extracellular enzyme, secreted protein, agar plate test, proteomics analysis
