Lactic acid bacteria isolated from yak milk show probiotic potential

Area of Science:

• Microbiology
• Food Science
• Biotechnology

Background:

• The demand for effective probiotic strains is high in the food and health industries.
• Challenges exist in isolating and selecting novel indigenous probiotic candidates.
• Yak milk is a potential source of unique probiotic microorganisms.

Purpose of the Study:

• To investigate the probiotic potential of lactic acid bacteria isolated from Yak milk.
• To evaluate their health benefits, including cholesterol degradation, lactose digestion, and antimicrobial/antioxidant/anticancer activities.
• To identify promising strains for novel probiotic product development.

Main Methods:

• Isolation and in vitro screening of 17 lactic acid bacteria from Yak milk.
• Assessment of survival under acidic pH and bile concentrations.
• Evaluation of cholesterol degradation, lactose digestion, antimicrobial, antioxidant, and anticancer activities.
• Principal component analysis for strain selection criteria.

Main Results:

• Over 50% of strains met key probiotic criteria (acid/bile tolerance, adhesion).
• Most strains exhibited antimicrobial activity against tested pathogens.
• Several strains showed significant cholesterol degradation, with strain Yc being 1.5x more efficient than controls.
• Strain Lan4 demonstrated potent anticancer activity (87% apoptosis in Hela cells) with no toxicity to HEK293 cells.
• Approximately ten strains facilitated lactose digestion.

Conclusions:

• Selected lactic acid bacteria from Yak milk possess excellent probiotic properties and significant health benefits.
• These strains are viable candidates for developing novel probiotic preparations.
• Further research is warranted to explore their full application potential in enhancing public health.