Extraction and Biochemical Characterization of Exopolysaccharides Produced from Lactococcus Lactis Strain Isolated from Fermented Dairy Products

Abstract

Exopolysaccharides (EPSs) are high–molecular-weight, complex carbohydrate biopolymers secreted extracellularly by various microorganisms, particularly lactic acid bacteria (LAB). LAB are well recognized for their remarkable capacity to synthesize diverse types of EPSs, which have attracted significant scientific and industrial interest. These LAB-derived EPSs exhibit numerous health-promoting properties and are extensively utilized in the food and pharmaceutical sectors. Several optimized methods have been developed for the production, extraction, purification, and characterization of LAB-produced EPSs and molecular docking studies. The simplest preliminary assessment of EPS production involves examining colony morphology, where ropy or mucoid textures indicate EPS formation. Ethanol precipitation is a common and effective technique for extracting EPSs from cell-free supernatants. Quantification of total carbohydrate content is typically performed using the phenol–sulfuric acid method. The structural and functional properties of EPSs are characterized through a variety of analytical techniques. Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and X-ray diffraction (XRD) are used to elucidate structural features. Surface morphology is examined using scanning electron microscopy (SEM) and the screened bioactive compound constituents against multiple therapeutic targets, namely BRAF, EGFR2, HDAC8, PPARA, VEGFR2, and RET, with binding energies ranging from weak to strong interactions. Overall, research on EPS from LAB involves isolating EPS-producing strains from probiotic products and their characterization.