Objective Microorganisms in the traditional koumiss sampled from 4 regions in Xinjiang were isolated and identified. This was of importance for enriching local microbial data.

Method 30 samples of koumiss were collected from Aheqi, Gejiagou, Wusu and Nalati. Microbes including lactic acid bacteria and yeasts in samples were isolated and purified through plate cultivation method with morphological characteristics observed. Then the amplification and sequencing of their rDNA/ITS gene fragments and phylogenetic analysis were carried out.

Result Seventy strains, which included 64 bacteria and 6 yeasts belonging to 18 species, 7 families, and 12 genera, were isolated. Of them, 10 strains from Aheqi belonged to one family, 2 genera, and 4 species, including Bacillus cereus, Bacillus albus, Heyndrickxia oleronia and Heyndrickxia ginsengihumi; 25 strains from Gejiagou belonged to 6 families, 10 genera, and 9 species, including Lentilactobacillus kefiri, Lactobacillus helveticus, Lactiplantibacillus plantarum, Companilactobacillus crustorum, Acetobacter pasteurianus, Leuconostoc mesenteroides, Enterococcus durans, Monosporozyma unispora and Pichia ethanolica; 7 strains from Wusu belonged to one family, one genus, and 4 species, including Bacillus cereus, Bacillus albus, Bacillus paramycoides and Bacillus wiedmannii; and 28 strains from Nalati belonged to 6 families, 7 genera, and 9 species, including Lentilactobacillus kefiri, Lacticaseibacillus paracasei, Lactobacillus helveticus, Lactiplantibacillus plantarum, Acetobacter pasteurianus, Acetobacter malorum, Monosporozyma unispora, Pichia ethanolica and Pichia fermentans. Among all the strains, Enterococcus durans constituted the dominant species, accounting for 17.14%, while Lacticaseibacillus paracasei and Lactobacillus helveticus comprised 14.29%, respectively, and the others collectively made up 54.28%.

Conclusion The 70 strains isolated from 30 samples of koumiss were identified with taxological classifications. Among them, there were a total of 39 strains of lactic acid bacteria including Lentilactobacillus kefiri, Lacticaseibacillus paracasei, Lactobacillus helveticus, Lactiplantibacillus plantarum, Companilactobacillus crustorum, Leuconostoc mesenteroides and Enterococcus durans, 6 strains of yeasts, and 25 strains of other microorganisms. The information would aid further studies on probiotics and other health-related functions of the traditional product.