Bacterial and Fungal Communities in Pu'er Tea Samples of Different Ages

Abstract

Pu'er is a major kind of postfermented tea and is made with a "large leaf" variety of Camellia sinensis (C. sinensis assamica), whose distribution is limited to the mountains of southern Yunnan, China. The quality of Pu'er tea is believed to increase with storage (aging, maturing) because of postfermentation by microbes. The effect of storage period (from < 1 to 192 mo) on the bacteria and fungi in Pu'er tea was investigated by a culture-dependent and a PCR-DGGE method. The individual numbers of fungi and bacteria decreased with increasing storage time and were significantly greater in ripened tea than in raw Pu'er tea. Both methods indicated that yeast, Aspergillus spp., and Penicillium spp. were the dominant fungi in almost all the samples. However, the common bacteria detected by the culture-dependent method were species of Pseudomonas, Achromobacter, Alcaligenes, Sporosarcina, and Bacillus, whereas those detected by PCR-DGGE were species of Staphylococcus, Arthrobacter, and Streptomyces. According to ordination analysis, bacterial community structure differed between ripened and raw Pu'er tea. Bacterial diversity was positively correlated with aging time, while fungal diversity in both raw and ripened tea increased during the first 60 mo of aging and then decreased. Changes in polyphenol content were correlated with the changes in fungal diversity. These results suggest that the relationship between storage time and the quality of Pu'er tea is complex and involves changes in polyphenol content and microbial abundance and diversity.

Insights into the microbial diversity and community dynamics of Chinese traditional fermented foods from using high-throughput sequencing approaches

“…The role of Pu-erh tea as an anti-oxidative agent for reducing cholesterol levels and aiding digestion is well acknowledged (Hou et al, 2009;Cao et al, 2011). There are two main categories of Pu-erh tea, namely raw and ripened (Tian et al, 2013). The processing of raw Pu-erh tea includes the fixation, rolling, and drying of leaves before the tea is compressed into bricks, cakes, or other shapes.…”

“…Microbiota has a significant influence on the quality of Pu-erh tea, especially during the wet piling. Various kinds of bio-techniques including DGGE (Tian et al, 2013;Yang et al, 2013), pyrosequencing (Lyu et al, 2013), metatranscriptomics (Jiang et al, 2012), metagenomics and metaproteomics (Zhao et al, 2015) have been used to investigate the microbial composition during the piling process. However, the microbiological profiles of Pu-erh tea are not well understood.…”

Microbial Succession and the Dynamics of Chemical Compounds during the Solid-State Fermentation of Pu-erh Tea

“…[7]. Additionally, a high level of microbiota diversity was gained using culture-independent approaches, such as denaturing gradient gel electrophoresis (PCR-DGGE) [8][9][10][11], a 16S rRNA gene clonal library [7], and pyrosequencing analyses [12,13]. Recently, we investigated the microbial communities and enzymes of an SSF processing sample of PFPT (collected on day 21) using 454 pyrosequencing and LC-MS/MS approaches [13].…”

Isolation, characterization and application of theophylline-degrading Aspergillus fungi

“…and Penicillium spp. are the filamentous fungal genera commonly associated with SSF of pu-erh tea [52][53][54], particularly A. niger, A. sydowii and A. tamarii having been widely reported as the dominant fungi in the SSF of pu-erh tea. The assessment in agar mediums with theophylline as carbon source showed that six Aspergillus isolates could survive in theophylline agar mediums, which suggested that those six candidate isolates (Table 3) could utilize theophylline as potential carbon source directly in the absence of other carbon source.…”