title: The Microbiome and Metabolites in Fermented Pu-erh Tea as Revealed by High-Throughput Sequencing and Quantitative Multiplex Metabolite Analysis.
abstract: Pu-erh is a tea produced in Yunnan, China by microbial fermentation of fresh Camellia sinensis leaves by two processes, the traditional raw fermentation and the faster, ripened fermentation. We characterized fungal and bacterial communities in leaves and both Pu-erhs by high-throughput, rDNA-amplicon sequencing and we characterized the profile of bioactive extrolite mycotoxins in Pu-erh teas by quantitative liquid chromatography-tandem mass spectrometry. We identified 390 fungal and 629 bacterial OTUs from leaves and both Pu-erhs. Major findings are: 1) fungal diversity drops and bacterial diversity rises due to raw or ripened fermentation, 2) fungal and bacterial community composition changes significantly between fresh leaves and both raw and ripened Pu-erh, 3) aging causes significant changes in the microbial community of raw, but not ripened, Pu-erh, and, 4) ripened and well-aged raw Pu-erh have similar microbial communities that are distinct from those of young, raw Ph-erh tea. Twenty-five toxic metabolites, mainly of fungal origin, were detected, with patulin and asperglaucide dominating and at levels supporting the Chinese custom of discarding the first preparation of Pu-erh and using the wet tea to then brew a pot for consumption.
authors.affiliation: School of Life Sciences, Shanxi University, Taiyuan, Shanxi, China.|Department of Plant and Microbial Biology, University of California, Berkeley, California, United States of America.
authors.forename: Yongjie
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Section of Mycology, Norwegian Veterinary Institute, Oslo, Norway.
authors.forename: Ida
authors.initials: I
authors.lastname: Skaar
authors.affiliation: Center for Analytical Chemistry, Department of Agrobiotechnology, University of Natural Resources and Life Sciences, Tulln, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Sulyok
authors.affiliation: State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Xingzhong
authors.initials: X
authors.lastname: Liu
authors.affiliation: Bureau of Culture and Sports, Puer, Yunnan, China.
authors.forename: Mingyong
authors.initials: M
authors.lastname: Rao
authors.affiliation: Department of Plant and Microbial Biology, University of California, Berkeley, California, United States of America.
authors.forename: John W
authors.identifier: http://orcid.org/0000-0002-5794-7700
authors.initials: JW
authors.lastname: Taylor
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics; D044822:Biodiversity; D019295:Computational Biology / Q000379:methods; D005285:Fermentation; D005658:Fungi / Q000145:classification / Q000235:genetics; D059014:High-Throughput Nucleotide Sequencing; D055442:Metabolome; D055432:Metabolomics / Q000379:methods; D054892:Metagenome; D056186:Metagenomics / Q000379:methods; D064307:Microbiota; D013662:Tea / Q000737:chemistry* / Q000235:genetics / Q000382:microbiology*
chemical_list: D013662:Tea