Application of microbial exopolysaccharides (EPSs) in biomedical sciences

Event Purpose

Dr. Masoud Hamidi, a postdoctoral researcher in the Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, USA, will present his research on: Microbial exopolysaccharides (EPSs) have emerged as highly versatile biopolymers with substantial potential in biomedical sciences due to their tunable physicochemical properties, excellent biocompatibility, and diverse intrinsic bioactivities, including antioxidant, antimicrobial, immunomodulatory, and wound-healing effects. In this seminar, I will first present a concise overview of microbial EPSs, covering their structural diversity, biosynthetic pathways, and key functional characteristics that support their application in biomedical sciences. The central focus of the presentation will be our recent research on yeast-derived EPSs, with particular emphasis on an exopolysaccharide isolated from Papiliotrema terrestris PT22AV. This biopolymer has demonstrated strong cytocompatibility with fibroblasts and macrophages, notable antibacterial activity, and dose-dependent acceleration of full-thickness skin wound healing in vivo. These findings highlight its promising potential as a bioactive component in wound dressings and as a scaffold material for 3D tissue regeneration. In addition, I will discuss a second EPS from Rhodotorula mucilaginosa GUMS16 (DOI: 10.1016/j.ijbiomac.2022.02.113) potently inhibited BCR-ABL-positive K562 leukemia cells (IC50 1500 μg/mL), sparing normal cells while reducing colony formation, elevating LDH release 2.75-fold, modulating apoptotic/anti-apoptotic genes, disrupting cell cycle progression, and enhancing DPPH scavenging for synergistic anticancer/antioxidant utility.  Together, these case studies illustrate how the rational selection, characterization, and engineering of microbial EPSs can effectively bridge fundamental polysaccharide science with translational applications in wound care, infection control, and advanced biomaterials design.