Homemade Koumiss Research Articles

Isolation and Identification of Lactic Acid Bacteria from Koumiss in Xinjiang, China

Koumiss is a traditional fermented drink in Xinjiang, which is rich in microorganisms. In this study, seven strains of lactic acid bacteria were isolated and identified from Xinjiang homemade koumiss by traditional separation culture method, Gram staining method and 16s rDNA sequencing analysis. The observation of colonial morphology showed that seven isolates mostly round milky white with convex surfaces, and the results of gram staining showed that all seven isolates were gram-positive. The isolates were considered to be Enterococcus sp., Streptococcus gallolyticus, Lactobacillus fermentum, Lactobacillus delbrueckii subsp. Bulgaricus, Lactobacillus fermentum, Bacillus cereus and Enterococcus durans separately through 16s rDNA sequencing analysis. These results can provide scientific basis for the diversity of lactic acid bacteria in dairy products in Xinjiang, and provide theoretical support for the development of lactic acid bacteria food.

Dynamic evaluation of the nutritional composition of homemade koumiss from Inner Mongolia during the fermentation process

Koumiss plays an important role in income generation for herdsmen and the daily nutritional intake of local people. In this study, the pH, protein, fat, lactose, lactic acid, amino acid, and vitamin content of koumiss were investigated during the entire fermentation period. The results showed that the protein content of fresh mares’ milk and koumiss ranged from 1.86 ± 0.07% to 2.22 ± 0.08%; fat content ranged from 0.74 ± 0.16% to 1.480 ± 0.08%; VB1 concentration ranged from 1.48 ± 0.12 to 4.86 ± 0.42 µg/100 g; VB2 concentration ranged from 2.48 ± 0.12 µg/100 g to 4.86 ± 0.32 µg/100 g; and VE concentration ranged from 99.90 ± 0.05 to 44.63 ± 0.63 µg/100 g. There were significant differences between fresh mares’ milk and koumiss in relation to VE content. The content of 17 amino acids ranged from 2.40 ± 0.11 µg/100 g (for MET) to 39.64 ± 0.01 µg/100 g (for GLU). Fresh mares’ milk and aged koumiss had high nutritional value; however, unripe koumiss (i.e., with a shorter fermentation time) had low nutritional value. Based on the data from this study, an optimized manufacture process for koumiss is proposed. Practical applications The dynamic changes of chemical and nutritional composition of koumiss were evaluated in this present paper. The nutrient content of koumiss is the highest at the point of 12 hr fermentation. The optimized manufacture process for koumiss is proposed based on the result of this study. This paper will provide the basic information for koumiss industrial application.

Выделение микроорганизмов из казахских кисломолочных продуктов с антагонистической активностью в отношении дрожжей рода Candida

An increase in the number of severe candidiasis, the growing incidence of antimicrobial resistance of the pathogens responsible for these infections, as well as their harmful side effects, necessitate developing new and more effective antifungal agents. In this context, the elaboration and utilization of functional fermented milk products with microorganisms harbouring antifungal activity and thus promoting the elimination of opportunistic Candida yeasts from the body, could be of great interest. The microbiota of Kazakh national sour-milk beverages derived from mare's and camel's milk has a multidirectional health effect on the human body, but the antagonistic activity of members of these microbiota against yeast species responsible for candidiasis have not yet been studied. The aim of this work was to isolate microorganisms, with antagonistic activity against Candida yeast species from Kazakh national fermented milk beverages. The study of antagonistic activities of various dairy products of local (both domestic and commercial) production against C. albicans using well-diffusion assays showed effective suppression of yeast growth with homemade koumiss samples. Associations of microorganisms from various koumiss samples also showed antagonistic activities after performing successive inoculations and fermentations of cow's milk and whey. When cultured in cow's milk, these associations had an increased activity against C. krusei 25. The highest antagonistic activity against C. glabrata 589 was found for three associations cultured in whey. After plating the most promising associations on MRS media, 41 bacteria with were isolated from selected associations based on their colony morphotype, 28 of which were lactic acid bacteria, while the other were presumptive acetic bacteria. Thirty-four yeast isolates were also selected. In the present study, autochthonous strains of microorganisms that inhibited Candida spp. growth, including Candida strains exhibiting a high resistance to both lactic acid bacteria metabolites (intestinal and vaginal isolates of C. albicans) and antifungal antibiotic fluconazole (C. glabrata 589 and S. krusei 25), were selected for the first time. The isolated microorganisms will be used to create consortia and apply as starters to develop new functional beverages with antifungal activity against opportunistic Candida yeast species. Key words/phrases: koumiss, lactic acid bacteria, Candida yeast antagonists.

Complete genome sequence of Lactobacillus paracasei CAUH35, a new strain isolated from traditional fermented dairy product koumiss in China

Lactobacillus paracasei CAUH35 was isolated from homemade koumiss, a traditional fermented dairy product with beneficial effects on human health. The genome consists of a circular 2,770,411bp chromosome and four plasmids. Genome analysis revealed the presence of gene clusters involved in the production of exopolysaccharides and bacteriocin. The complete genome sequence of L. paracasei CAUH35 will provide genetic basis for further comparative and functional genomic analyses.

Comparison of lactobacilli isolated from Chinese suan-tsai and koumiss for their probiotic and functional properties

Suan-tsai and koumiss are traditional Chinese fermented foods. This study compared the dominant lactobacilli in suan-tsai and koumiss for their probiotic properties, cholesterol-lowering potentials and antioxidant activities. Thirty Lactobacillus strains were isolated from eight homemade suan-tsai samples (8 Lactobacillus plantarum and 6 Lactobacillus brevis) and seven homemade koumiss samples (7 Lactobacillus helveticus, 5 Lactobacillus acidophilus, 2 L. plantarum and 2 Lactobacillus casei), and they were subsequently analyzed for the above parameters. No significant differences were found between the mean antioxidant activities of the lactobacilli isolated from koumiss and suan-tsai, whereas the lactobacilli isolated from koumiss exhibited higher mean bile tolerance, adhesion to HT-29 cells, cholesterol removal and percentage of bile salt hydrolase-positive strains than did those isolated from the suan-tsai samples. Thus, koumiss could be considered a better source of potential probiotics, especially cholesterol-lowering probiotics, than suan-tsai.

Effects of traditional homemade koumiss on some hematological and biochemical characteristics in sedentary men exposed to exercise

We evaluated the effects of koumiss on some hematological and biochemical characteristics of persons who exercise. Eighteen sedentary males were assigned to three equal groups: koumiss (K), koumiss + exercise (KE) and exercise alone (E). Leukocytes (WBC), differential leucocyte count, erythrocytes (RBC), hemoglobin (HGB), hematocrit (HCT), platelet (PLT), glucose, total cholesterol, triglycerides, high density lipoprotein (HDL), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were assessed In blood samples. By the end of the study, triglycerides (TG) and cholesterol levels tended to decrease in all groups, but the decrease was significant only at day 15 for the KE group. HDL tended to be increased in all groups at day 15, but the increase was significant only in the KE group. We found that koumiss had beneficial effects on some hematological and biochemical characteristics.

Complete Genome Sequence of Lactococcus lactis subsp. lactis KLDS4.0325

We report the complete genome sequence of Lactococcus lactis subsp. lactis KLDS4.0325, a probiotic bacterium isolated from homemade koumiss in Xinjiang, China. We have determined the complete genome sequence of strain KLDS4.0325, which consists of a chromosome and three plasmids and reveals genes that are likely to be involved in dairy fermentation and that have probiotic qualities.

Selection of potential probiotic lactobacilli for cholesterol-lowering properties and their effect on cholesterol metabolism in rats fed a high-lipid diet

The objectives of this study were to screen probiotic characteristics of lactobacilli isolated from traditionally homemade koumiss products in Xinjiang and Inner Mongolia of China, and to determine and compare the effect of the Lactobacillus strains in vivo on lipid metabolism in rats fed with a high-lipid diet. Three out of 68 strains of Lactobacillus isolated from the koumiss were screened for bile-salt resistance, acid tolerance, and different hypocholesterolemic properties. The cholesterol-lowering effects of the 3 screened strains were estimated in rats fed a high-lipid diet by determination of serum lipids, liver, and fecal cholesterol, fecal total bile acids, and short-chain fatty acids. After a 4-wk feeding period, in comparison with the control group, the groups LIP-1 and MG9-2 had a significant reduction in serum total cholesterol, triglyceride and low-density lipoprotein cholesterol, and significantly increased high-density lipoprotein, the group E7301 had similar effects on serum lipids, but the change was not significant. The groups LIP-1, MG9-2 and E7301 had a significant reduction in liver cholesterol content and an increase in fecal cholesterol content compared with the control group. Total bile acid excretion was significantly higher in rats fed MG9-2 than the other groups. Rats fed diets containing lactic acid bacteria strains had significantly higher propionic acid and butyric acid concentrations in the feces compared with the control. Results indicated that the 3 screened Lactobacillus strains were able to lower cholesterol in vitro, and reduce cholesterol effectively in vivo. The mechanisms behind the hypocholesterolemic effect of 3 strains are likely to be diverse and will need further investigation.

Complete Genome Sequence of the Probiotic Strain Lactobacillus casei BD-II

Lactobacillus casei BD-II, a patented probiotic strain (U.S. patent 7,270,994 B2), was isolated from homemade koumiss in China and has been implemented in the industrial production as starter cultures. Here we report the complete genome sequence of BD-II, which shows high similarity with the well-studied probiotic BL23.

Validation of reference genes for real-time quantitative PCR studies in gene expression levels of Lactobacillus casei Zhang

Lactobacillus casei Zhang, a potential probiotic strain isolated from homemade koumiss in Inner Mongolia of China, has been sequenced and deposited in GenBank. Real-time quantitative PCR is one of the most widely used methods to study related gene expression levels of Lactobacillus casei Zhang. For accurate and reliable gene expression analysis, normalization of gene expression data using one or more appropriate reference genes is essential. We used three statistical methods (geNorm, NormFinder, and BestKeeper) to evaluate the expression levels of five candidate reference genes (GAPD, gyrB, LDH, 16s rRNA, and recA) under different culture conditions and different growth phases to find a suitable housekeeping gene which can be used as internal standard. The results showed that the best reference gene was GAPD, and a set of two genes, GAPD and gyrB (which were the most stable reference genes), is recommended for normalization of real-time quantitative PCR experiments under all the different experimental conditions tested. The systematic validation of candidate reference genes is important for obtaining reliable analysis results of real-time quantitative PCR studies in gene expression levels of Lactobacillus casei Zhang.

Complete Genome Sequence of Lactobacillus casei Zhang, a New Probiotic Strain Isolated from Traditional Homemade Koumiss in Inner Mongolia, China

Lactobacillus casei Zhang is a new probiotic bacterium isolated from koumiss collected in Inner Mongolia, China. Here, we report the main genome features of L. casei Zhang and the identification of several predicted proteins implicated in interactions with the host.

Proteomics Analysis of Lactobacillus casei Zhang, a New Probiotic Bacterium Isolated from Traditional Home-made Koumiss in Inner Mongolia of China

Lactobacillus casei Zhang, isolated from traditional home-made koumiss in Inner Mongolia of China, was considered as a new probiotic bacterium by probiotic selection tests. We carried out a proteomics study to identify and characterize proteins expressed by L. casei Zhang in the exponential phase and stationary phase. Cytosolic proteins of the strain cultivated in de Man, Rogosa, and Sharpe broth were resolved by two-dimensional gel electrophoresis using pH 4-7 linear gradients. The number of protein spots quantified from the gels was 487 +/- 21 (exponential phase) and 494 +/- 13 (stationary phase) among which a total of 131 spots were identified by MALDI-TOF/MS and/or MALDI-TOF/TOF according to significant growth phase-related differences or high expression intensity proteins. Accompanied by the cluster of orthologous groups (COG), codon adaptation index (CAI), and GRAVY value analysis, the study provided a very first insight into the profile of protein expression as a reference map of L. casei. Forty-seven spots were also found in the study that showed statistically significant differences between exponential phase and stationary phase. Thirty-three of the spots increased at least 2.5-fold in the stationary phase in comparison with the exponential phase, including 19 protein spots (e.g. Hsp20, DnaK, GroEL, LuxS, pyruvate kinase, and GalU) whose intensity up-shifted above 3.0-fold. Transcriptional profiles were conducted to confirm several important differentially expressed proteins by using real time quantitative PCR. The analysis suggests that the differentially expressed proteins were mainly categorized as stress response proteins and key components of central and intermediary metabolism, indicating that these proteins might play a potential important role for the adaptation to the surroundings, especially the accumulation of lactic acid in the course of growth, and the physiological processes in bacteria cell.

Evaluation of potential probiotics properties of the screened Lactobacilli isolated from home-made koumiss in Mongolia

Among thirtyLactobacillus strains, which were isolated and identified from the home-made koumiss in Mongolia,Lactobacillus helveticus MG2-1 was screened out for the best acid tolerance in artificial gastric juice at pH 3.0 after incubating for 3 h with the survival rate 96.15±4.22%. Furtherin vitro assessment revealed MG2-1 showed high tolerance to the artificial gastrointestinal juice and bile salts. Moreover, other desired probiotic properties, including the ability of sodium taurocholate deconjugation (with the amount of cholic acid liberated 2.95±0.11 μM), cholesterol removal (cholesterol removal rate 51.74±0.04%) and adhesion to Caco-2 cells (the adhesive rate 1.51±0.11%), were also observed. The results highlighted the probiotic potential of MG2-1, which deserved further investigation inin vivo studies to elucidate its health benefits.

Molecular cloning and characterisation of alpha subunit of H<sup>+</sup>-ATPase in Lactobacillus casei Zhang

The acid tolerance is an important property of Lactic acid bacteria as potential probiotics. H<sup>+</sup>-ATPase is considered a key gene in several bacteria with the ability of acid tolerance. We cloned and sequenced the full length cDNA of alpha subunit of H<sup>+</sup>-ATPase gene in <i>Lactobacillus casei</i> Zhang, which had been isolated from traditional home-made koumiss in Inner Mongolia of China. The results showed that the respective cDNA sequence is composed of 1530 nucleotides and codes a putative protein including 509 amino acids. In addition, we also reconstructed the phylogenic trees for H<sup>+</sup>-ATPase gene based on amino acids sequences of diverse strains of Lactic acid bacteria.

Identification of Lactobacillus from koumiss by conventional and molecular methods

Lactobacilli are considered to be one of the most important potential probiotics in the dairy industry. Twelve strains of Lactobacillus were isolated from home-made koumiss samples, a traditionally fermented mare milk in China. The isolates were identified based on physiological and biochemical characteristics and analysis of 16S RNA sequences. They were proven to be Lactobacillus helveticus, Lactobacillus fermentum,Lactobacillus casei and Lactobacillus plantarum. The results demonstrated that both methods were essential to identify an isolate accurately.