Sustainable Bioethanol Production from Corn Husk using Saccharomyces cerevisiae: Optimization of Key Parameters for Enhanced Yield

Abstract

Non-renewable fossil fuels dominate energy use globally, prompting a shift to renewable biofuels and utilizing underused agricultural residues. This study aimed to evaluate effective agricultural waste materials for biofuel production and to optimize cultivation conditions to improve yield. Among the tested agricultural wastes (arecanut husk, arecanut leaf, rice husk and corn husk) fermented with Saccharomyces cerevisiae, corn husk produced significantly higher bioalcohol yields. Utilizing corn husk in fermentation media (4 g/L yeast extract, 8g/L KH2PO4, 0.6 g/L (NH4)2SO4, 0.3 g/L peptone, 0.6 g/L MgSO4.7H2O) with baker's yeast (25 g/L) at 30 ± 2 °C, 100 rpm for 24 hours yielded 0.3% ethanol. Sequential optimization increased yields significantly. Extending fermentation to three days raised ethanol production by 1.6 times (0.5%). Hydrolyzing corn husk with 1M H2SO4 improved bioalcohol yields compared to other agents. Optimizing media pH to 7.0 further enhanced production. Increasing corn husk substrate to 40g/100ml boosted ethanol content from 0.7% to 1.1%. Higher yeast inoculum (75 g/L) elevated bioalcohol yield to 1.2%, compared to non-optimized conditions (25 g/L). The findings reveal that corn husk can serve as a valuable raw material for bioalcohol synthesis, emphasizing the importance of process optimization to maximize yield.
Keywords: Agricultural waste, Bioalcohol, Corn husk, Fermentation optimization, Lignocellulosic biomass, Saccharomyces cerevisiae