LIGNOCELLULOSIC BIOETHANOL PRODUCTION: CURRENT AND FUTURISTIC TRENDS

Abstract

Bioethanol production from lignocellulosic biomass has gained significance as an alternative renewable fuel source to mitigate the environmental impact caused by fossil fuels. Lignocellulosic biomass, such as agricultural scums, forestry waste, and dedicated energy crops, offers several advantages for bioethanol production due to its abundance, low cost, and non- competitiveness with food crops. This abstract explores the current state of bioethanol production from lignocellulosic biomass, its challenges, and futuristic trends. The conversion of lignocellulosic biomass to bioethanol involves three main steps: pre-treatment, enzymatic hydrolysis, and fermentation. Pre-treatment is crucial to overcome the obstinacy of lignocellulosic biomass, making it more susceptible to enzymatic attack. Various pre-treatment techniques, including physical, chemical and biological methods have been established to enhance biomass accessibility and enzymatic digestibility. Enzymatic hydrolysis involves the breakdown of complex polysaccharides into fermentable sugars like D-glucose or D-xylose using cellulolytic and hemicellulolytic enzymes while fermentation employs yeast or specific bacteria to convert sugars into bioethanol. In recent years, new trends have emerged to revolutionize lignocellulosic bioethanol production. One such trend is the utilization of consolidated bioprocessing (CBP), which objects to combine all three steps of bioethanol production into a single microorganism or enzyme system. CBP offers the potential for simplified process design, reduced costs, and increased efficiency. Various microorganisms, including engineered bacteria and fungi, are being explored for CBP to achieve higher bioethanol yields from lignocellulosic biomass. Moreover, advancements in synthetic biology and genetic engineering have flagged the way for tailor-made enzymes and microorganisms with improved characteristics for lignocellulosic bioethanol production. Researchers are focusing on designing enzymes with enhanced stability, activity, and specificity to achieve higher sugar release. Similarly, genetically engineered microorganisms capable of efficiently fermenting a broad spectrum of sugars and tolerating inhibitory compounds are being developed to maximize bioethanol yields. Furthermore, the integration of lignocellulosic bioethanol production with other biorefinery processes is gaining attention. By exploiting the by- products of bioethanol production, such as lignin and hemicellulose, for the production of value-added biofuels, or materials, the overall process finances can be improved. Integrated biorefineries offer the potential for a more sustainable and economically viable approach to utilizing lignocellulosic biomass. Bioethanol production from lignocellulosic biomass holds immense potential as a renewable and sustainable fuel source. Despite the challenges faced, trending approaches such as consolidated bioprocessing, synthetic biology and biorefinery integration are flagging the way for more effectual and economically feasible bioethanol manufacture. Continued research and development efforts in these areas will be crucial in realizing the full potential of plant tissue biomass for bioethanol manufacture and reducing dependence on fossil fuels