Detection Of Extracellular Enzymes And Initial Research On Proteomics Of The Dominant Strain For Dark Tea's Fermentation

Aspergillus cristatum and Aspergillus niger are respectively the dominant strains in the processing of dark tea products,such as Fuzhuan tea and Pu'er tea.These strains produced various metabolites through enzymatic action under certain hot and humid conditions,which play an important role in the formation of product flavor quality.Aspergillus cristatum FZ-2 and Aspergillus niger PE-3 from previous studies and systematically detected with spectrophotometry in the crude enzyme solution.There are six kinds of hydrolase,such as tannase,cellulase,protease,lipase,amylase,xylanase and four kinds of oxidase,such as polyphenol oxidase,peroxidase,catalase,and superoxide dismutase,and compare the ability of the two strains to produce enzymes.The results showed that the activity of tannase,cellulase,xylanase,amylase and lipase of strain PE-3 was extremely higher than that of strain FZ-2,while the activity of protease,catalase,polyphenol oxidase and peroxidase of strain FZ-2 was significantly higher than that of strain PE-3,and the activity of superoxide dismutase of strain PE-3 was slightly higher than that of strain FZ-2.The results showed that the two strains were rich in enzyme production,and the flavor quality of Fuzhuan Tea and Pu'er Tea was the result of various enzymatic enzymatic activities.At the same time,the activity of hydrolase and oxidase secreted by the two strains was significantly different.It was speculated that their use of tea and decomposition pathways should be Different.And it has been speculated that Pu-erh tea may exhibit a more sweet flavor than Fuzhuan tea.The strain FZ-2 cultured in liquid fermentation under different glycerol concentrations was studied.Among them,morphological observation,biomass determination and fermentation pH determination were performed on the strains at different water activities.Protein samples were purified and identified by SDS-PAGE.Finally,proteomics tests were performed,including Aspergillus coronary FZ-2 in two-dimensional electrophoresis and identification and analysis of protein profile.The results show that when the spores of Aspergillus coronaryus are in a sexual structure,they are more conducive to the resistance to adverse physiological environments.With the addition of glycerol,it was found that the original glyoxylate cycle metabolic pathway was adjusted to the tricarboxylic acid cycle.Some proteins,such as acetylornithine aminotransferase,S-adenosylmethionine synthase,10 kDa heat shock proteins(mitochondria),glutaredoxin,cysteine synthase 2,will activate and initiate the corresponding regulation mechanism only in the adverse environment of certain glycerol stress in vivo.The possible role of these proteins is related to environmental antagonism.