??????????????????????????????????? 2,3-Butanediol ????????????????????????????????????????????????????????????????????

Abstract

The environmental problems directly related to energy production and consumption include fossil fuel depletion, climate change, green-house gas emission, and solid waste disposal. Therefore, this study aims to investigate microbial conversion of glycerol waste generated from biodiesel production process to produce value-added 2,3 butanediol (2,3 BD). The pure bacterial strain capable of generating 2,3 BD from waste glycerol was isolated from palm oil sludge. The newly isolated strain Bacillus subtilis PSU-Bio-MEC have been identified by 16S rRNA sequences and later evaluated optimization conditions, including pH (X1) (6-8), glycerol concentration (X2) (5-15 g/L), and peptone concentration (X3) (1-3 g/L) for 2,3-BD production from glycerol waste by deploying response surface methodology (RSM) combined with Box�Behnken Design (BBD) at 37 �C and 150 rpm. The RSM results illustrated that the optimum conditions of pH 6, initial glycerol concentration 15 g/L and peptone concentration 2 g/L provides the highest 2,3-BD production of 3.42 g/L.????????????????????????????????????????????????????????????? ?????? ?????????????????????????? ??????????????????????????? ?????????????????????? ???????????????????? ??????????????????????????????????????????????????????????????????????????????????????????????????????????????? ?????? 2,3 butanediol (2,3-BD) ????????????????????????????????????????????? 2,3-BD ?????????????????????? ????????????? Bacillus subtilis PSU-Bio-MEC ???????????????????? 2,3-BD ????????????????????????????????????? 16S rDNA sequences ???????????????????????????????????????????????????????? pH (X1) (6-8) ??????????????????????? (X2) (5-15 ???????????) ???????????????????? (X3) (1-3 ???????????) ?????????? 2,3-BD ??????????????????? ??????????????????????????? (Response Surface Methodology (RSM) ?????????????????????????? Box�Behnken ???????????????????????????????????????? 37 ???????????? ????????????? 150 ?????????? ?????????????????????????????? 2,3-BD ?????? pH 6 ??????????????????????? 15 ??????????? ???????????????????? 2 ??????????? ???????????? 2,3-BD ?????? 3.42 ???????????