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Yunnan Pu'er tea is dayezhong drying green raw tea leaves as raw material obtained by microbial fermentation, microorganisms play an important role in the formation of quality tea. Has been reported isolated fungi, there are Aspergillus, Penicillium, Rhizopus, and yeast and other microorganisms are for room temperature fungi, few reports on bacteria. The modern the puer tea reactor fermentation process, at least 45 days, while the the general fermentation temperature above 50 ℃, not turning up to above 70 ℃, is typical of high-temperature fermentation, the presence of thermophilic bacteria and their role can not be ignored. In this study, separation of thermophilic bacteria in the fermentation process as a starting point, as research subjects will be thermophilic bacteria and heat-resistant bacteria. The samples were collected from Yunnan Menghai the Pengcheng tea, are four isolation medium, each time turning the collected samples were diluted coating culture, the growth of colonies counted based on colony characteristics, a preliminary understanding of the fermentation process of tea trend of changes in the number of thermophilic bacteria. Finally, the separation and purification of 13 bacteria, can better growth above 50 ℃. Of all the growth characteristics of the thermophilic bacteria, this experiment is carried out for each strain Determination of the optimum growth temperature and the growth temperature range, and the role played by the various strains in different tea fermentation stage preliminary judgment. Also determined the optimum growth pH of the various strains and growth pH value range, the initial judgment of each strain growth in tea environment adaptability. The results show that 10 of the heat-resistant bacteria, and 3 for thermophilic bacteria, and the optimum pH for basic neutral, well adapted to the Pu'er tea high temperature fermentation environment. About 13 kinds of strains to explore the effect of tea fermentation. In the comparison of the control group, the study of the various strains of added tea polyphenols in tea fermentation process, caffeine, free amino acids, theaflavins, thearubigins theabrowns content. Found that the addition of tea fermentation strains have varying degrees of impact. The paper also microbial metabolic properties, explore the enzymatic properties of 13 strains. The results showed that the fermentation broth of each strain has a different degree of isoamylase, endoglucanase, exo-glucanase, pectinase, alkaline protease activity, and some strains of enzyme production capacity is relatively strong. These microbial metabolic nature given the strains in the tea fermentation process functions. Finally, some strains extracted genomic amplification of 16S rDNA sequencing, sequence comparison to construct a phylogenetic tree. Determine the genus of the various strains, and than the right of each strain with the standard strain homology found three belong to the actinomycetes. Typical two strains of the physiological and biochemical tests, and found that there are some differences in the physiological and biochemical characteristics similar to known strains.
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