2014, 30(3):114-120.
Abstract:
Lactic acid bacteria (LAB) with probiotic were isolated and screened from intestinal tract of longevity crowd, and the ability of cholesterol-reducing in vitro were investigated. The results showed that nine of eighty strains had high survival rates in simulated gastric juice for 3 hours, being of 26.60%, 24.30%, 22.50%, 16.72%, 46.61%, 16.10%, 19.80%, 19.60% and 17.80%, respectively. The survival rates of o2 were the highest, which were 21.31%, 13.35%, 12.43% respectively in 0.3%, 0.5% and 1.0% bile salt. Nine strains were sensitive to ampicillin, penicillin G, chloramphenicol, and sensitive or moderately sensitive to tetracycline, rifampicin and ciprofloxacin. They had bacteriostatic activity against Salmonella, Staphylococcus aureus and Escherichia coli. The bacteriostatic activities of V9 and o2 to Salmonella, Staphylococcus aureu were higher. The inhibition diameters were 12.00 mm and 11.40 mm respectively, and all the nine strains had high bacteriostatic activity to Escherichia coli, with the inhibition diameters of more than 7.0 mm. The cholesterol-reducing rates of f10, o2, T1 and V9 were 45.85%, 40.76%, 41.70%, 42.87%, respectively, higher than other strains, which were identified as Enterococcus faecium, Weissella Cibaria, Lactobacillus casei and Lactobacillus fermentum by physiological and biochemical test as well as 16srDNA sequence alignment. These strains could be good candidate probiotics strains for auxiliary hypolipidemic.