Bacterial and fungal diversity in Laphet, traditional fermented tea leaves in Myanmar, analyzed by culturing, DNA amplicon-based sequencing, and PCR-DGGE methods

Laphet is a traditional fermented food in Myanmar, made from tea leaves (Camellia sinensis) by fermentation with limited air passage. We performed microbial diversity analyses on 14 Laphet products collected from different locations in Myanmar. Amplicon-based sequencing results revealed Lactobacillus and Acetobacter were abundant bacteria and Candida, Pichia, Cyberlindnera, and Debaryomyces were abundant yeast. Using selective media, eight species of lactic acid bacteria and nine species of yeast were isolated; Lactobacillus plantarum and L. collinoides were dominant bacteria and Pichia manshurica, Candida boidinii, and Cyberlindnera jadinii were major yeasts. PCR-DGGE analysis confirmed that most of the dominant bacterial and yeast species found in culture dependent analysis were present in Laphet samples. Microbial diversity and pH of Laphet were different between samples from tea plantation area and local markets due to possible differences in incubation time periods. When tannase activity was tested, 23 among 29 bacterial isolates and two among 36 yeast isolates showed positive activities. These findings provide new insights into microbial diversity of Laphet and increased our understanding of the core bacterial and yeast species involved in the manufacture of Laphet.