o:608 From agricultural waste to biofuel: enzymatic potential of a bacterial isolate Streptomyces fulvissimus CKS7 for bioethanol production en Abstract: Purpose: To avoid a negative environmental and economic impact of agricultural wastes, and following the principles of circular economy, the reuse of agricultural wastes is necessary. For this purpose, isolation of novel microorganisms with potential biotechnological application is recommended. The current researches in bioethanol production are aimed to reduce the production costs using low-cost substrates and in-house produced enzymes by novel isolated microorganisms. In line with this, in this study valorization of these agricultural by-products by novel isolate S. fulvissimus CKS7 to biotechnological value added products was done. Methods: Standard microbiological methods were used for the isolation and characterization of strain. Enzymes activities were determinated using DNS method while, the ethanol concentration was determined based on the density of the alcohol distillate at 20 °C. Results: The maximal enzymatic activities for amylase, cellulases (carboxymethyl cellulase and Avicelase), pectinase and xylanase were achieved using rye bran as a waste substrate for CKS7 growth. Obtained crude bacterial enzymes were used for enzymatic hydrolysis of lignocellulosic materials including horsetail waste, yellow gentian waste, corn stover, cotton material and corona pre-treated cotton material. The maximum yield of reducing sugars was obtained on horsetail waste and corona pre-treated cotton material. Waste brewer’s yeast Saccharomyces cerevisiae was successfully used for the production of bioethanol using horsetail waste hydrolysate and corona pre-treated cotton material hydrolysate. Conclusion: The obtained results showed that bacterial strain CKS7 has a significant, still unexplored enzymatic potential that could be used to achieve a cleaner, environmental friendly and economically acceptable biofuel production. Solid state fermentation · Streptomyces fulvissimus CKS7 · Hydrolytic enzymes production · Lignocellulosic waste hydrolysis · Bioethanol 1552099 10.1007/s12649-020-00960-3 2022-09-08T11:43:32.050Z 44 yes 46 Katarina Mihajlovski Faculty of Technology and Metallurgy, University of Belgrade 46 Aneta Buntić Institute of Soil Science 0000-0002-7068-1804 46 Marija Milić Faculty of Technology and Metallurgy, University of Belgrade 46 Mirjana Rajilić‑Stojanović Faculty of Technology and Metallurgy, University of Belgrade 46 Suzana Dimitrijević‑Branković Faculty of Technology and Metallurgy, University of Belgrade application/pdf 893585 https://unilib.phaidrabg.rs/o:608 no yes 1 70 92000001 71A05 Waste and Biomass Valorization 12 165 174 2021