Comprehensive evaluation of bioactive properties and metabolomic profiling of probiotic bacteria Lactococcus lactis (MKL8)

Abstract

This study evaluated the bioactivity and the metabolomics of Lactococcus lactis MKL-8, a probiotic bacterium that was isolated from Murraya koenigii; contributing to broadening the diverse ecological diversity of Lactococcus lactis. The primary objective of this study was to explore the multifunctionality of MKL-8 by bringing together its bioactive potential and its metabolomic profile to assess its suitability for probiotic use. Identification of probiotic strains demonstrating multifunctional therapeutic properties along with proven safety is the most significant challenge in meeting increasing demand for natural therapeutic substitutes to synthetic drugs. MKL-8 showed high antioxidant activity with 90.19% inhibition, exhibits an anti-diabetic effect with 60% inhibition of α-amylase, and anti-inflammatory activity with 99% inhibition of protein denaturation, demonstrating significant potential as a natural therapeutic agent. The strain also exhibited significantly high ability to form biofilm and synthesized a considerable amount of Exopolysaccharides (EPS). GC-MS analysis revealed bioactive metabolites which are reported in the literature to have, immunomodulatory effects, antioxidant, collagen synthesis, and wound healing properties. The presence of these compounds was further affirmed by FT-IR spectroscopy, further indicating the importance of MKL-8 as a multifunctional probiotic. This paper presents the isolation and versatile applications of MKL-8, demonstrating it is a valuable natural probiotic strain. Collectively, these findings establish MKL-8 having potential health benefits making it a promising choice for progressive probiotic applications both in the healthcare industry and the functional food sector.

Keywords: Lactococcus lactis; Anti-diabetic; Anti-inflammatory; Anti-oxidant; Biofilm; Secondary metabolites.

Fig. 1

Graphical representation of antioxidant activity of (a) MKL8 and (b) Ascorbic acid showing percentage inhibition at various concentrations. Data are expressed as the mean ± standard deviation of three replicates (n = 3); p < 0.0001.

Fig. 2

Gelatinase production by (a) MKL8 (b) Enterococcus faecalis (c) Control.

Fig. 3

GC-MS chromatogram for MKL8.

Fig. 4

FTIR spectrum of MKL8 with solvent chloroform.