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Huang Y.,Huazhong Agricultural University | Xiao X.,Yiling District | Cong L.,Puer Institute of Pu Erh Tea | Wu M.,Huazhong Agricultural University | Yao Y.,Huazhong Agricultural University
LWT - Food Science and Technology | Year: 2016

Microbial tea products are widely welcomed for their unique quality characteristics. However, the quality characteristics of pickled tea, a microbial tea product traditionally consumed in most Asian countries remain unclear. Therefore, the quality characteristics of pickled tea processed using Camellia sinensis leaves through anaerobic solid-state fermentation were analyzed. During 60-d fermentation, the free amino acids, caffeine, and tea polyphenols in pickled tea kept much stable, the soluble sugar content showed significant and continuous decrease, but the water extract showed a continuously increasing trend. The optimal fermentation time for pickled tea was 30 d, at which its normal quality characteristics were formed: the sensory quality was the best, most free amino acids evidently increased, a high level of gallic acid was produced up to 25.7 g/kg, and volatile compounds were mainly alkanes such as heptadecane and hexadecane. It is the first report that high levels of gallic acid in a microbe-fermented tea processed by anaerobic fermentation reached to that levels in Galla chinensis, which will benefit development of a functional tea with high levels of active components and understanding the microbial transformation of tea components through anaerobic fermentation. © 2016 Elsevier Ltd. Source

Zhang W.,Beijing University of Chemical Technology | Yang R.,Beijing University of Chemical Technology | Yang R.,Puer Institute of Pu Erh Tea | Fang W.,Beijing University of Chemical Technology | And 4 more authors.
International Journal of Food Microbiology | Year: 2016

This study aimed to characterize the thermophilic fungi in pile-fermentation process of Pu-erh tea. Physicochemical analyses showed that the high temperature and low pH provided optimal conditions for propagation of fungi. A number of fungi, including Blastobotrys adeninivorans, Thermomyces lanuginosus, Rasamsonia emersonii, Aspergillus fumigatus, Rhizomucor pusillus, Rasamsonia byssochlamydoides, Rasamsonia cylindrospora, Aspergillus tubingensis, Aspergillus niger, Candida tropicalis and Fusarium graminearum were isolated as thermophilic fungi under combination of high temperature and acid culture conditions from Pu-erh tea pile-fermentation. The fungal communities were analyzed by PCR-DGGE. Results revealed that those fungi are closely related to Debaryomyces hansenii, Cladosporium cladosporioides, A. tubingensis, R. emersonii, R. pusillus, A. fumigatus and A. niger, and the last four presented as dominant species in the pile process. These four preponderant thermophilic fungi reached the order of magnitude of 107, 107, 107 and 106 copies/g dry tea, respectively, measured by real-time quantitative PCR (q-PCR). The results indicate that the thermophilic fungi play an important role in Pu-erh tea pile fermentation. © 2016 Elsevier B.V. Source

Li M.,Yunnan Agricultural University | Li M.,Puer Dian Hongjun Biotechnology Technology Development Co. | Wang C.,Yunnan Agricultural University | Li R.,Yunnan Agricultural University | And 4 more authors.
Chinese Journal of Environmental Engineering | Year: 2013

The strain GGHN08-116 of Schizophyllum commune was applied to remedy heavy metal (Hg, Pb and Cr) contaminated soil by using cottonseed-hulls and corn stalks as solid fermentation substrates. Through the growth and penetration of fungal hyphae in the soil, the contents of exchangeable heavy metal ions, and the fungal ability for accumulating these ions in contaminated soil were studied. Furthermore, by applying the solid fermentation substrates on contaminated soil in pots which planted carrots, the contents of Hg, Pb and Cr ions in soil and the quality and yield of carrot roots were observed. The results showed that the strain could penetrate into soil to 5 cm deep, and produce fruit bodies. The pH of treated soil was lower than the control, but with no significant differences. The contents of exchangeable Hg and Cr ions decreased significantly, but the contents of Pb had no significant differences compared to the control. Except Hg, the amounts of exchangeable Pb and Cr ions in the fungal fruit bodies were in excess of the specified standards GB 7096-2003 and GB 2762-2005. After the solid fermentation treatment, the contents of exchangeable Hg, Pb and Cr ions in soil significantly decreased; the Hg and Pb ions were not detected in the carrot roots and stalks, and the Cr contents in carrot were corresponded with the specified standard GB 2762-2005. Therefore, the strain GGHN08-116 and its solid fermentation products is able to remedy the Hg, Pb and Cr contaminated soil. Source

Zhao L.,Kunming University of Science and Technology | Jia S.,Kunming University of Science and Technology | Tang W.,Kunming University of Science and Technology | Sheng J.,Yunnan Agricultural University | And 2 more authors.
International Journal of Molecular Sciences | Year: 2011

Pu-erh tea is a kind of fermented tea with the incorporation of microorganisms' metabolites. Unlike green tea, the chemical characteristics and bioactivities of Pu-erh tea are still not well understood. Using water extracts of Pu-erh tea, we analyzed the tumor cell growth inhibition activities on several genetically engineered mouse tumor cell lines. We found that at the concentration that did not affect wild type mouse embryo fibroblasts (MEFs) growth, Pu-erh tea extracts could inhibit tumor cell growth by down-regulated S phase and cause G1 or G2 arrest. Further study showed that Pu-erh tea extracts down-regulated the expression of mutant p53 in tumor cells at the protein level as well as mRNA level. The same concentration of Pu-erh tea solution did not cause p53 stabilization or activation of its downstream pathways in wild type cells. We also found that Pu-erh tea treatment could slightly down-regulate both HSP70 and HSP90 protein levels in tumor cells. These data revealed the action of Pu-erh tea on tumor cells and provided the possible mechanism for Pu-erh tea action, which explained its selectivity in inhibiting tumor cells without affecting wild type cells. Our data sheds light on the application of Pu-erh tea as an anti-tumor agent with low side effects. © 2011 by the authors; licensee MDPI, Basel, Switzerland. Source

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