Production of 2,3‐butanediol by fermentation of enzymatic hydrolysed bagasse from agave mezcal‐waste using the native Klebsiella oxytoca UM2‐17 strain

Abstract Background 2,3‐butanediol is a chemical component with wide industrial applications, such as biofuels and chemical precursors. Reducing 2,3‐butanediol production costs is a high priority and recent focus has been on its biological synthesis from raw renewable materials rather than through conventional chemical procedures. In this study, a 2,3‐butanediol native bacterial producer was selected for the fermentation of Agave cupreata bagasse waste by enzymatic hydrolysation to obtain 2,3‐butanediol. Results The native Klebsiella oxytoca UM2‐17 strain was selected to efficiently produce 2,3‐butanediol on synthetic mineral media. Using glucose (100 g L −1 ) and glucose: xylose (50 g L −1 :50 g L −1 ) as sugar sources obtained titres of 29.36 g L −1 and 25.9 g L −1 of 2,3‐butanediol, corresponding to yields of 0.29 g g −1 and 0.26 g g −1 , respectively. Agave bagasse solid waste after acid pre‐treatment was utilized to obtain enzymatic hydrolysates, obtaining liquors with glucose/xylose/arabinose at 25.8 g L −1 with efficiency of ∼52.5% sugar conversion from residual solid pre‐hydrolysed bagasse. The production of 2,3‐butanediol through batch fermentation of the enzymatic‐hydrolysate by the UM2‐17 strain showed total depletion of glucose and xylose, achieving a maximal production of 10.3 g L −1 of 2,3‐butanediol plus 0.28 g L −1 ethanol, corresponding to 2,3‐butanediol yield of 0.40 g g −1 . Conclusion The results indicate that A. cupreata bagasse waste from mezcal beverage elaboration is a sustainable bioresource for production of 2,3‐butanediol by fermentation of enzymatic bagasse‐hydrolysate using the K. oxytoca UM2‐17 strain. © 2019 Society of Chemical Industry