Bacterial communities in Lanna pickled mustard green and fermented soy bean from three ethnic groups in Mae Hong Son province and development of product from isolated bacterial strain

Abstract

Lanna, or the northern region of Thailand, is home to diverse ethnic groups, each with unique foods and cultural heritage. Some of their important traditional foods are fermented foods, which involve beneficial bacteria in their production processes. This research analyzed bacterial communities in two types of fermented foods, namely pickled mustard greens and fermented soy beans (Thua Nao), from three ethnolinguistic groups: Karen (Sino-Tibetan language family), Lawa (Austroasiatic language family), and Shan (Kra-Dai language family). Genomic DNA from these fermented foods was extracted and sequenced using Next Generation Sequencing on the Illumina platform, focusing on the 16S rRNA gene. The study, using Qiime2 software, found that the predominant bacteria in the pickled mustard greens, including Weissella and Lactobacillus, varied among the products of the three ethnic groups. In Thua Nao, Bacillus was the most abundant bacterial group. The presence of certain bacterial genera, such as Ignatzschineria, Yaniella, Atopostipes, and Proteus, in these foods indicated a need for improving the hygiene condition during the production processes. However, the predominant bacterial taxa in both fermented foods imply a high probiotic potential, shows the suitability for the conservation of these two fermented food cultures. Additionally, the research isolated Lactobacillus pentosus from Karen’s pickled mustard greens, showing its probiotic potential, survival in acid (37.4%) and bile (85.5%), and antibacterial properties, leading to the development of a Ma-Mao flavored probiotic jelly drink.