Vol.:(0123456789) 1 3 Journal of Polymers and the Environment https://doi.org/10.1007/s10924-019-01546-4 ORIGINAL PAPER Scleroglucan Production by Sclerotium rolfsii ATCC 201126 from Amylaceous and Sugarcane Molasses‑Based Media: Promising Insights for Sustainable and Ecofriendly Scaling‑Up Alejandra Leonor Valdez 1  · Jaime Daniel Babot 1,2  · Jochen Schmid 3,4  · Osvaldo Daniel Delgado 1,5  · Julia Inés Fariña 1 © Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract Scleroglucan is a β-glucan exopolysaccharide (EPS) efciently produced by Sclerotium rolfsii ATCC 201126, with attrac- tive 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 PM 20 (8.41 g C/L + NaNO 3 as N-source) at shake-fask-scale vs. alternative C-source versions, soluble starch and sugarcane molasses led to efcient EPS production. At bioreactor scale, starch-based medium led to highest EPS production (7.95 g/L), recovery (~ 52%) and pro- ductivities (0.11 g EPS/L h; 0.018 g EPS/g biomass  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 efcient, low-cost, and scalable EPS production, thus opening new perspectives for medium reformulation and sustainable EPS production. Keywords Sclerotium rolfsii · Scleroglucan · Corn starch · Sugarcane molasses · Sustainable production Introduction Polymers play a fundamental role in our society, with a production of 180 million tons per year [1]. Among them, petroleum-derived or synthetic polymers, along with being non-biodegradable and environmentally prejudicial, are unfortunately the most widespread. In this scenario micro- bial polysaccharides, with outstanding and versatile physico- chemical properties and an ecofriendly production-degrada- tion profle, rapidly became promising competitors. Their production exhibits certain advantages such as: speed, as compared with the 3–6 months required for plant polysac- charides [2]; controlled manufacturing conditions, which avoids product variability; and low environmental impact, as they neither compromise large tracts of land nor exhibit risks of environmental pollution (oil spills or non-biodegra- dability). From them, microbial exopolysaccharides (EPSs), i.e. those that once produced are excreted into the surround- ing medium, have attracted worldwide interest. As already reported, scleroglucan is an EPS that can be efciently produced by the selected flamentous fun- gus Sclerotium rolfsii ATCC 201126, under given and optimized cultivation conditions [3, 4]. This biopolymer is a neutral and hydrosoluble β-1,3-β-1,6-glucan. Its high molecular weight—approximately 5 × 10 6  Da—and triple helical structure are the main fundamentals for the high vis- cosity imparted to its aqueous solutions. Biocompatibility, * Julia Inés Fariña jifarina@yahoo.com; jifarina@proimi.org.ar 1 Mycodiversity & Mycoprospection Lab, Planta Piloto de Procesos Industriales Microbiológicos, PROIMI-CONICET, Av. Belgrano y Pje. Caseros, T4001 MVB SM Tucumán, Tucumán, Argentina 2 Present Address: Centro de Referencia para Lactobacilos, CERELA-CONICET, T4000 ILC SM Tucumán, Tucumán, Argentina 3 Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, 94315 Straubing, Germany 4 Present Address: Department of Biotechnology and Food Science, Norwegian University of Science and Technology, 7034 Trondheim, Trøndelag, Norway 5 Faculty of Exact and Natural Sciences, National University of Catamarca, K4700 Catamarca, Argentina