Bacterial community and composition of different traditional fermented dairy products in China, South Africa, and Sri Lanka by high-throughput sequencing of 16S rRNA genes

Abstract

The bacterial community and predictive functionality of 51 traditional fermented dairy products (raw milk, yoghurt, fermented milk curd, wrum, milk silk-skin, butter, milk granule, koumiss, and cheese) from three countries (China, Inner Mongolia and Xinjiang; South Africa; Sri Lanka) were investigated and compared by high-throughput sequencing of 16S rRNA genes. Lactobacillus, Streptococcus, and Lactococcus were the major genera in raw milk, yoghurt, fermented milk curd, wrum, and milk silk-skin samples from Inner Mongolia, whereas the butter samples contained Rhodococcus and Pseudomonas. Lactobacillus was the main genus in yoghurt, milk granule, and koumiss samples from Xinjiang. Streptococcus was the predominant genus in yoghurt and cheese samples from South Africa and Sri Lanka. Streptococcus thermophilus was the dominant species in samples from South Africa and Sri Lanka, the prevalent species in samples from Xinjiang were Lactobacillus helveticus and Lactobacillus delbrueckii subsp. bulgaricus. The butter samples from Inner Mongolia were abundant in Rhodococcus erythropolis. Functional analysis demonstrated that Rhodococcus erythropolis and Lactobacillus helveticus play an important role in carbohydrate and lipid metabolism. In summary, mining the bacterial communities of different traditional fermented dairy products from different countries paves the way in the isolation of functional microorganisms and exploration of their functions.