Selection of a galactose-positive mutant strain of Streptococcus thermophilus and its optimized production as a high-vitality starter culture.

Streptococcus thermophilus is a common starter in yogurt production and plays an important role in the dairy industry. In this study, a galactose-positive (Gal) mutant strain, IMAU20246Y, was produced using the chemical mutagen N-methyl-N'-nitro-N-nitrosoguanidine (NTG) from wild-type S. thermophilus IMAU20246, which is known to have good fermentation characteristics.

Bacterial composition and function during fermentation of Mongolia koumiss.

Koumiss is a fermented mare's milk beverage that has attracted increasing attention due to its nutritional richness and important economic value. Bacteria in koumiss play a major role in pH decreasing and reducing spoilage through bacterial inhibition. The dynamic changes in nutritional content were determined firstly during fermentation, and then the metagenomics sequencing technology was applied to profile koumiss core microbiota at the species level.

Investigating bacterial population structure and dynamics in traditional koumiss from Inner Mongolia using single molecule real-time sequencing.

Koumiss is considered as a complete dairy product high in nutrients and with medicinal properties. The bacterial communities involved in production of koumiss play a crucial role in the fermentation cycle. To reveal bacterial biodiversity in koumiss and the dynamics of succession in bacterial populations during fermentation, 22 samples were collected from 5 sampling sites and the full length of the 16S ribosomal RNA genes sequenced using single molecule real-time sequencing technology.

Assessment of the bacterial and fungal diversity in home-made yoghurts of Xinjiang, China by pyrosequencing.

Background: The aim of this study was to gain a deeper knowledge of the bacterial and fungal community diversity in local home-made yoghurts from Zhaosu and Tekesi counties, Xinjiang, China, where a relatively high proportion of the ethnic minority population resides.

Results: The bacterial and fungal community diversity in 22 home-made yoghurt samples was analyzed by pyrosequencing. This approach revealed the presence of six bacterial and two fungal phyla, comprising 69 bacterial and 20 fungal genera respectively, among all samples.

454 pyrosequencing reveals changes in the faecal microbiota of adults consuming Lactobacillus casei Zhang.

Probiotics are believed to help to maintain a healthy balance of the human gut microbiota. Lactobacillus casei Zhang (LcZ) is a novel potential probiotic isolated from the naturally fermented food koumiss. To better understand the impact of this potential probiotic on human intestinal microbiota, 24 subjects were randomly recruited for a longitudinal study: the subjects were required to consume LcZ for 28 days, and faecal samples were collected prior to, during and after the LcZ consumption phase.

Characterization of fecal microbiota across seven Chinese ethnic groups by quantitative polymerase chain reaction.

The human gut microbiota consists of complex microbial communities, which possibly play crucial roles in physiological functioning and health maintenance. China has evolved into a multicultural society consisting of the major ethnic group, Han, and 55 official ethnic minority groups. Nowadays, these minority groups inhabit in different Chinese provinces and some of them still keep their unique culture and lifestyle.