Lactic acid bacteria isolated from yak milk show probiotic potential

Abstract

Probiotic industries strive for new, efficient and promising probiotic strains that impart a positive impact on consumer health. Challenges are persisting in isolation, screening, and selection of the new indigenous probiotic strains. In the present research, we explored the probiotic potential of 17 lactic acid bacteria isolated from Yak milk in a series of in vitro tests. We also demonstrated their health benefits, i.e., cholesterol degradation, lactose digestion, antimicrobial activity, antioxidant, and anticancer activities. Principal component analysis revealed that more than 50% of the strains fulfilled the examined criteria, e.g., survival in acidic pH, bile concentrations, and adherent property. Approximately all the strains produced antimicrobial substances against the maximum number of tested strains including clinical strains. Most strains degraded cholesterol in comparison to the reference probiotic strain whereas strain Yc showed 1.5 times higher the degradation efficiency of the control strain. Lan4 strain exhibited remarkable anticancer activity and induced the maximum apoptosis (87%) in the Hela cells and was non-toxic to the non-cancerous HEK293 cells. Around ten strains showed positive lactose digestion. Overall, this can be concluded that selected lactic acid bacteria revealed excellent probiotic properties along with desirable health benefits. These strains need to be further investigated in details for their application in the development of novel probiotic preparations for the improvement of public health.

Safety and Antioxidant Properties of Five Probiotic <i>Lactobacillus plantarum</i> Strains Isolated from the Digestive Tract of Honey Bees

“…Li et al [50] reported that the DPPH free radical scavenging rate by the intact cell of the L. plantarum C88 strain was 53.05% at the dose10 10 UFC/ml. In a study analogous to us, Kaur et al [51] documented about more than 50% of this scavenging capacity of theYbis, L5 and Yb LAB strain with their ICs. Furthermore, our results showed that ICs exhibited higher DPPH radical scavenging rate than that of CFSs.…”

Characterization of Lactic Acid Bacteria Isolated From the Gastrointestinal Tract of a Wild Boar as Potential Probiotics

“…The intimate contact between probiotics and pathogenic bacteria occurs during co-aggregation and the antimicrobial substances produced by the former can inhibit pathogens (61). In addition, the reports of the antiviral and anticancer activities are good examples of much broader than originally considered health-promoting activities attributed to probiotic LAB (62,63). Although the antiviral and anticancer abilities of the isolated LAB were not characterized in this study, it would be an interesting topic for further studies.…”

Investigation of the Lactic Acid Bacteria in Kazak Cheese and Their Contributions to Cheese Fermentation

“…The microflora in raw camel milk consists of Streptococcus, Lactococcus, Weissella, Pediococcus, Lactobacillus, and Enterococcus (Fguiri et al, 2016;Fugl et al, 2017). However, yak milk contains Lactobacillus species, Enterococcus species, Lactococcus species, Leuconostoc species, and Weissella cibaria (Kaur et al, 2017), whereas Lactococcus, Lactobacillus, Leuconostoc, Streptococcus, Enterococcus, Macrococcus, Weissella, and Bacteroidetes were the dominant flora in raw milk (Gao et al, 2017). Furthermore, LABs function as a starter culture in raw animal milk and contribute to the fermentation of cheese, kefir, and yogurt.…”