Production of Bio-Ethanol from Agricultural Waste Using Microbes: An Overview

Abstract

Ethanol produced through the fermentation of plant biomass is considered an environment friendly alternate to fossil fuels. Bioethanol and biodiesel, commonly known as second-generation biofuels, are produced through biological processes using agro-industrial waste and are considered sustainable, safe, and ecofriendly. These biofuels can minimize the emission of carbon dioxide and reduced the world’s dependence on fossil fuel. This review article focuses on three generations of biofuels, particularly the production of biofuel using fungal biocatalysts specifically Aspergillus niger and Saccharomyces cerevisiae and the mechanism by which they convert biomass into biofuel. A. niger is known for releasing cellulolytic and pectolytic enzymes to hydrolyze biomass and survive against toxins, while S. cerevisiae produces invertase and zymase enzymes to convert sucrose into fructose and glucose sugars, and then further convert fructose and glucose into ethanol. The main purpose of this review is to explore alternative techniques for generating biofuels, using as few harmful chemicals as possible and reducing time consumption.