Production of xylose polysaccharides using newly isolated Chlamydomonas sp. Xylok with nitrogen depletion

The growing interest in sustainable production of polysaccharides derived from microalgae has stimulated our pursuit of a novel biorefinery approach capable of simultaneously generating exopolysaccharide (EPS) and biomass using a new microalgal strain. In the present study, a novel strain, designated as Chlamydomonas sp. Xylok, was successfully isolated from river water contaminated with copper and zinc. This unique strain exhibited remarkable attributes, demonstrating both a high EPS generation capacity and exceptional biomass production compared to previously documented microalgal types. To optimize EPS produced from Chlamydomonas sp. Xylok, a comprehensive investigation of influential parameters, including light intensity, temperature, and crucial nutrient elements, such as nitrogen, phosphorus, calcium, and magnesium, was conducted. Notably, under nitrogen-depleted conditions, the strain exhibited a rapid and remarkable 49 % increase in EPS production within a mere 24-h timeframe compared to normal growth conditions. In addition to its EPS production potential, Chlamydomonas sp. Xylok holds industrial importance owing to its higher yield of xylose compared to other existing microalgal strains. This unique characteristic presents a cost-effective and efficient method for producing xylose, making it more appealing for various commercial applications.