Ethanol Production from Gmelina arborea Wood Wastes by Saccharomyces cerevisiae using Submerged Fermentation

M.R Adedayo,O.A Yahaya,A.E Ajiboye

doi:10.4314/njb.v37i2.14

Abstract

Lignocellulose wastes are the most abundant residues on the surface of the earth. This project studies the possibility of ethanol production from a forestry waste. Wood wastes from Gmelina arborea were treated with dillute sulfuric acid to break down the lignin component. Fermentation for ethanol production was done using baker’s yeast (Saccharomyces cerevisiae ATCC 204508/S288c) for 120 hours using submerged fermentation, and the pH, reducing sugar, specific gravity and lignin content were determined using standard techniques. Ethanol concentration and yield were measured via vinometer and ethanol standard curve techniques. From the results, the highest pH was obtained at 72 hours of the fermentation period. The reducing sugar content and specific gravity decreased over the fermentation time . The acid-pretreated wood wastes gave a maximum ethanol concentration of 3.84 % and a yield of 7.60 ml/g as measured from the vinometer and ethanol standard curve methods at 72 and 96 hours of fermentation, respectively. About 13.6% v/v of ethanol was recovered from the distillation process employed to separate the components of the product generated after fermentation. The observations in this research reveal the possibility of producing ethanol from G. arborea wood wastes and under optimized culture conditions. This could serve as an alternate means of biofuel generation and hence value addition to the wastes. Keywords: Gmelina arborea, Saccharomyces cerevisiae, Ethanol, Submerged fermentation

Highlights

Bioethanol production has been the interest of modern-day scientists who are constantly searching for alternative, ecofriendly and renewable sources of energy (Saini et al, 2015; Priyanka et al, 2019; Kumar et al, 2020)
The solid material remaining after hydrolysis was Assay for Ethanol yield and concentration considered as lignin
There was an increasing trend in ethanol yield, a peak was attained, followed by decrease in ethanol yield. This was contrary to the report of Michelle (2011) where ethanol yield from corn stover increased throughout the period of fermentation

Summary

Introduction

Bioethanol production has been the interest of modern-day scientists who are constantly searching for alternative, ecofriendly and renewable sources of energy (Saini et al, 2015; Priyanka et al, 2019; Kumar et al, 2020). Solid state fermentation (SSF) involves growing microorganisms directly on substrates with low quantities of water (Cavalieri et al, 2003). It is widely accepted and used in many industries for several processes (Durand, 2003). Wastes from this wood is enormously generated yearly, most often burnt in the open air, causing environmental pollution and increase in cost of waste treatment Using this waste as a source of fermentable sugar for bioethanol production will remedy the menace. The aim of this research is to investigate the potential use of lignocellulosic material (wood waste from Gmelina arborea) in the fermentation process for the production of ethanol

Materials and Methods

Discussion

Findings

Conclusion