Scleroglucan Production by Sclerotium rolfsii ATCC 201126 from Amylaceous and Sugarcane Molasses-Based Media: Promising Insights for Sustainable and Ecofriendly Scaling-Up

Abstract

Scleroglucan is a β-glucan exopolysaccharide (EPS) efficiently produced by Sclerotium rolfsii ATCC 201126, with attractive properties for a wide range of industries. Its production was herein comparatively assessed with nine alternative C- and twelve N-sources. When comparing conventional sucrose-based Production Medium PM20 (8.41 g C/L + NaNO3 as N-source) at shake-flask-scale vs. alternative C-source versions, soluble starch and sugarcane molasses led to efficient EPS production. At bioreactor scale, starch-based medium led to highest EPS production (7.95 g/L), recovery (~ 52%) and productivities (0.11 g EPS/L h; 0.018 g EPS/gbiomass h). Molasses, though leading to lower EPS production (5.11 g/L), could be envisaged as a promising agroindustrial sub-product for adding value and innovation. Oxalate side-product varied with C- and N-sources, with no clear detrimental relationship with EPS production. Agroindustrial sub-products showed then to be suitable as alternative substrates for efficient, low-cost, and scalable EPS production, thus opening new perspectives for medium reformulation and sustainable EPS production.