Journal of Advances in Microbiology

Aim: This study evaluated the effect of a probiotic consortium (70% yeast, 30% bacteria) on lipid metabolism in Triton X-100/high cholesterol-induced hyperlipidemic rats.

Study Design: Male Wistar rats (50-110 g) were obtained from Onyewuchi Farm, a certified animal farm located at Ifite Awka, Anambra State. Rats were randomized into different groups.

Place and Duration of Study: The study was carried out in the laboratories of the Microbiology and Biochemistry Department of Nnamdi Azikiwe University, Awka, Nigeria. This study was conducted over duration of 2 months at intervals.

Methodology: Twenty-four Wistar rats were divided into four groups (n = 6): normal control, hyperlipidemic control (HCD), low-dose probiotic (30 mg/kg), and high-dose probiotic (40 mg/kg). The animals were acclimatized for seven days in the animal house and fed with normal animal feed. Hyperlipidemia was induced by administering a single injection of Triton X-100 intraperitoneally at a dose dependent on the weight (100 mg/kg body weight) of the rats. A normal control group of rats received an equivalent volume of saline. The rats were slaughtered after 14 days of probiotics bacteria and yeast combination treatment. The stomach content, blood, liver were harvested and used for further analysis. After 14 days of probiotic administration, biochemical and microbial analyses were performed.

Results: Rat fed with HCD fasting blood glucoses significantly increased to (90.33 mg/dL) when compared to the Normal Diet group which had 68.67 mg/dL. Treatment with Probiotic significantly reduced glucose levels to 53.33 mg/dL (low dose) and 76 mg/dL (high dose). The rats fed with HCD had the body weight gain of 22 g which was significantly higher than that of the Normal Diet group (17.67 g), while probiotic supplementation reduced weight gain to 18.33 g (low dose) and 17 g (high dose), Total cholesterol significantly increased (p < 0.05) in HCD rats (231.08 mg/dL) compared to the Normal group (135.99 mg/dL), but decreased markedly following probiotic treatment to 146.0 mg/dL (low dose) and 143.96 mg/dL (high dose). Similarly, triacyl glyceride levels rose significantly in HCD rats (342.92 mg/dL) but decreased to 238.75 mg/dL (low dose) and 249.58 mg/dL (high dose) after probiotic administration. LDL-C levels increased significantly in the HCD group (108.49 mg/dL) but were reduced to 99.92 mg/dL (low dose) and 60.78 mg/dL (high dose), while HDL-C dropped in the HCD group (52.89 mg/dL) and improved significantly with probiotic treatment to 50.44 mg/dL (low dose) and 76.22 mg/dL (high dose). Gut microbiota analysis showed that HCD reduced beneficial lactic acid bacteria (LAB) and increased coliform counts. Gastric analysis revealed that probiotics significantly increased gastric pH (p < 0.05) from 1.42 ± 0.10 (HCD) to 1.93 ± 0.08 (low dose) and 2.00 ± 0.12 (high dose), suggesting a buffering and gastroprotective effect, while total acidity and gastric volume were not significantly affected (p > 0.05).

Conclusion: The probiotic combination effectively ameliorated high-fat diet–induced hyperlipidemia, reduced LDL-C, elevated HDL-C, improved glycemic control, restored gut microbial balance, and protected gastric function. These findings support the potential of yeast–bacterial probiotic formulations as a functional dietary supplement for the management of hyperlipidemia and metabolic disorders.