A three-stage culture process for improved exopolysaccharide production by Tremella fuciformis

Tremella fuciformis produces several bioactive secondary metabolites including exopolysaccharides. Cultivation of the fungus was carried out in a three-stage process consisting of a 1.5-day cultivation with orbital shaking at 200 rpm, a 1.5-day cultivation with reciprocal shaking at 200 strokes, and a 1.5-day cultivation with orbital shaking at 200 rpm. Exopolysaccharide production and specific production rate reached 5.80 g L−1 and 0.15 d−1, respectively, which is an increase of 260% and 200% compared with the corresponding values for fermentations with orbital shaking only, and of 243% and 150% compared with the corresponding values for fermentations with reciprocal shaking only. The three-stage culture method is time-saving and easy to operate.