The scale-up cultivation of Candida utilis in waste potato juice water with glycerol affects biomass and β(1,3)/(1,6)-glucan characteristic and yield

New ideas on production of yeast origin -glucan preparations for industrial application are attracting interest considering market development of that high-value functional polysaccharide. Sellecting an efficient yeast producer and designing culture conditions are a prerequisite for obtaining high yield of beta-glucan. The aim of this study was to describe at the first time the influence of the mode of cultivation (shake-flasks and batch fermentation) and time of culture on characteristic and yield of biomass and beta(1,3)/(1,6)-glucan preparations of Candida utilis ATCC 9950 after cultivation in medium based on waste potato juice water supplemented with 10% of glycerol. After shake-flask culture, the biomass was characterized by higher protein content (app. 26.5%) compared to 19% after batch fermentation while the cultivation on a biofermentor scale promoted polysaccharides biosynthesis. The highest output of purified beta(1,3)/(1,6)-glucan preparation (5.3g(d.w.)/L), containing app. 85% of that polysaccharide, was found after 48h cultivation in biofermentor. Batch fermentation promoted biosynthesis of alkali-insoluble beta(1,3)/(1,6)-glucan fraction, decreasing the content of (1,6)-glucan. The yield of beta(1,3)/(1,6)-glucan synthesis was 0.063 (g/g glycerol), while the productivity of that polysaccharide reached 0.094 (g/L/h). Longer batch fermentation (72h) resulted in reduction of production efficiency of beta-glucan preparation under studied conditions. The results of the study provide a new efficient biotechnological solution to produce high-value beta-glucan preparations of C. utilis origin based on valorization of agro-waste potato juice water with glycerol.