Enhanced ethanol production using hydrophobic resin detoxified Pine forest litter hydrolysate and integrated fermentation process development supplementing molasses

Abstract

High ethanol demand to make up the targets of the future gradual replacement of gasoline it is essential to look for hybrid technologies using rst generation and second-generation biofuel feedstock's. The current study used a two-step sequential pre-treatment ( rst dilute alkali, then dilute acid) of Pine (Pinus roxburghii) forest litter (PFL), for bioethanol production. Further, the sacchari cation of pre-treated PFL was optimized through response surface method using Box-Behnken Design, wherein 0.558 g/g of reducing sugar was under optimized conditions: 12.5% (w/v) of biomass loading, 10 FPU of enzyme, 0.15% (w/v) of Tween-80 in 48 h. During fermentation using Saccharomyces cerevisiae NCIM 3288 strain, the ethanol titre was 22.51 g/L, which was enhanced to 27.38 g/L after detoxi cation of PFL hydrolysate with hydrophobic resin (XAD-4). Furthermore, the hydrolysate was supplemented with molasses (total initial sugar: 100 g/L), wherein 46.02 ± 2.08 g/L ethanol was produced with 0.482 g/g yield and 1.92 g/l/h productivity. These results, showed that BOLT-ON Technology involving integration of molasses, increases the initial sugar availability leading to enhanced ethanol production, therefore can be compatible in bio-re neries to produce high titer ethanol.