Effect of Lactobacillus plantarum BS25 on Cholesterol Levels in vitro and in BALB/c Mice (Mus musculus L.)

Abstract

Background and Objectives: The risk of developing cardiovascular disease due to high cholesterol level has driven the development of functional foods that can maintain normal or lower cholesterol levels. This study determined the ability of two candidate probiotics isolated from traditional Filipino fermented food, Lactobacillus plantarum BS25 in mango-soymilk drink (BS25M) and Pediococcus acidactili 3G3 in dark chocolate drink (3G3C), to reduce cholesterol levels in vitro. Subsequently, the candidate probiotic that had higher cholesterol reduction, L. plantarum BS25, was added to the chocolate drink and used in the in vivo determination of cholesterol reduction.

Methodology: In vitro determination of cholesterol level reduction was carried out using the cholesterol assimilation assay. Induction of hypercholesterolemia was done by feeding the mice 3% cholesterol-enriched diet for nine weeks, after which, one group was administered with the chocolate drink containing 10¹¹ to 10¹² CFU/mL BS25 (BS25C) every other day for five weeks while the other group was given the placebo. Blood cholesterol and triglyceride levels were determined at several time points.

Results and Conclusions: Results of the in vitro study showed a significant difference (p>0.05) in the cholesterol assimilating ability of BS25M (96.11 μg/mL;58.8%) and the unfermented drink (M) (3.89 μg/mL;1.5%), suggesting that the cholesterol reduction was due to L.plantarum BS25. Both the 3G3 and 3GC set-ups reduced cholesterol levels at 5.06% and 5.82%, respectively; however, these were not significantly different from the negative control. The uninoculated chocolate drink did not reduce cholesterol levels (0%). Comparison between the two strains showed that there was higher cholesterol reduction by BS25 both in the bacterial isolate alone (17.45% vs. 5.06%) and fermented drink (58.8% vs 5.82%) set-ups. Hence, L. plantarum BS25 was used for the in vivo experiment, which showed that the mean serum cholesterol levels measured at baseline and after induction of hypercholesterolemia (week 9) were significantly different for both groups (p=0.031). Descriptive statistics showed that at post treatment, the mean serum cholesterol reduction in the mice fed with BS25C was higher (48.05 mg/dL) than that of the control group, H (28.00 mg/dL). These results suggest that BS25 chocolate drink is a potential functional food that may effectively reduce cholesterol.