Elevated levels of cholesterol or triglycerides in the blood are one of the major risk factors for coronary heart disease, which is the foremost leading cause of death across the world. The aims of this study were to isolate and verify the potential probiotic strain and cholesterol-lowering capability from goat milk. The C03B-STR isolate had a broad-spectrum antibacterial property and exhibited remarkable bacteriostatic activity against Klebsiella pneumoniae ATCC 13883 (27.00 ± 1.73 mm), Pseudomonas aeruginosa ATCC 27853 (19.33 ± 0.57 mm) and Staphylococcus aureus ATCC 10832 (19.00 ± 1.00 mm) by agar well diffusion assay. This isolate is closely related to the 16S rDNA sequence of Acidipropionibacterium acidipropionici. Acidipropionibacterium acidipropionici C03B-STR can survive under acidic conditions (60.51 ± 0.02% of survival rate at pH 3.0 for 3 h) and was as bile-tolerant strain (> 80% of survival rate at 0.30% bile salts after 3 h of incubation). Furthermore, it showed significantly high cell surface hydrophobicity (74.36 ± 0.23%) and aggregation capability (> 83%) (p ≤ 0.05) but displayed low to moderate co-aggregation ability (44-61%). This strain can also be regarded as strongly adhesive (73.69 ± 0.74%) and inhibit pathogen attachment to the Caco-2 cell lines (39.20 ± 0.59-69.01 ± 0.29%). A. acidipropionici C03B-STR appeared to be safe (non-haemolytic) and controllable (sensitive to various antibiotics). Notably, it had the potential to suppress cholesterol uptake in Caco-2 cells (approximately 45%) and also reduced cholesterol level above 84% during the exponential phase under acidic conditions. Thus, A. acidipropionici C03B-STR from goat milk may be a promising novel potential cholesterol-lowering probiotic strain for application in functional foods and biotherapeutics.

• Klíčová slova
• Acidipropionibacterium acidipropionici, Acid and bile salt tolerances, Antimicrobial activity, Cholesterol-lowering property, Goat milk, Probiotic,
• Publikační typ
• časopisecké články MeSH

Bile acids are crucial for the uptake of dietary lipids and can shape the gut-microbiome composition. This latter function is associated with the toxicity of bile acids and can be modulated by bile acid modifying bacteria such as Eggerthella lenta, but the molecular details of the interaction of bacteria depending on bile acid modifications are not well understood. In order to unravel the molecular response to bile acids and their metabolites, we cultivated eight strains from a human intestinal microbiome model alone and in co-culture with Eggerthella lenta in the presence of cholic acid (CA) and deoxycholic acid (DCA). We observed growth inhibition of particularly gram-positive strains such as Clostridium ramosum and the gram-variable Anaerostipes cacae by CA and DCA stress. C. ramosum was alleviated through co-culturing with Eggerthella lenta. We approached effects on the membrane by zeta potential and genotoxic and metabolic effects by (meta)proteomic and metabolomic analyses. Co-culturing with Eggerthella lenta decreased both CA and DCA by the formation of oxidized and epimerized bile acids. Eggerthella lenta also produces microbial bile salt conjugates in a co-cultured species-specific manner. This study highlights how the interaction with other bacteria can influence the functionality of bacteria.

• Klíčová slova
• bile acids, eggerthella lenta, gut microbiome interaction, hydroysteroid dehydrogenase, metabolomics, metaproteomics,
• Publikační typ
• časopisecké články MeSH