Bioethanol Production from Agro-Industrial Residues by Exploiting Cellulolytic Bacteria: An Evaluation

The development of biofuels from sustainable feedstocks has garnered significant scientific attention due to their potential to provide energy and alternative fuels. Cellulosic feedstock has gained attention as an attractive option for bioethanol production due to its greater ability to substitute fossil fuels and its relatively lower cost as a feedstock. With the help of a cellulolytic enzyme system, cellulose can be altered to glucose which is a multi-valued product, in a considerably economical and biologically favourable process. Many microorganisms that can degrade cellulose have been isolated and identified. The primary objective of this study was to identify and assess the cellulase-producing bacteria present in soil samples collected from sugar cane bagasse residue. The evaluation of cellulase production in carboxy methyl cellulose (CMC) agar medium was carried out qualitatively following Congo red staining and NaCl treatment. This was performed by analysing the zones surrounding the potent colonies. To evaluate the production of bioethanol at a laboratory level, the isolate showing the greatest enzyme activity was selected. Cellulase production has been facilitated by utilizing agro-industrial wastes such as rice bran, rice straw, sugarcane bagasse, wheat straw, and wheat bran, which have been used as substrates. A process of ethanolic fermentation was carried out by utilizing Saccharomyces cerevisiae for 24-48 hours. Subsequently, the bioethanol produced was subjected to quality evaluation by using titration, esterification, and iodoform tests. These results indicate the ability to produce ethanol from agricultural waste by cellulolytic bacteria, which makes it an attractive option for making money from waste.