Effect of Substrate Combination on the Yields of Fermentable Sugars from Lignocellulosic Biomass Hydrolyzed by Fungal Isolates.
No Thumbnail Available
Date
2022
Journal Title
Journal ISSN
Volume Title
Publisher
Published by Department of Science Education, Federal University of Technology Minna
Abstract
The sustainability and economic viability of biofuel production depend largely on the abundance and cost effectiveness of lignocellulosic biomass which is subject to seasonal and regional variability. This study investigated the effect of combining some locally available lignocellulosic biomass in Nigeria, on the yields of fermentable sugars, which are intermediates in the conversion of lignocellulose to biofuel, due to fungal hydrolysis. Rice husk (RH), corn cob (CC), sawdust (SD), wheat bran (WB) and guinea corn husk (GCH) were separately milled into powder and pretreated using 0.25N sodium hydroxide (NaOH) solution. The substrates were suspended in mineral salt media individually, and in various combinations. Fungi were isolated and assayed for cellulolytic activities. Aspergillus oryzae produced the highest activities as clearance zone (60.00±0.06 mm) on carboxyl methyl cellulose agar, endoglucanase (0.35 IU mL-1) and exoglucanase (0.66 IU mL-1) among the four fungal isolates, and was used to hydrolyze the substrates both in solid and submerged states. The product of hydrolysis was assayed for reducing sugar, pentose and total sugar. The mixture of CC, WB and GCH yielded the highest reducing sugar (49.50 mg mL-1). The highest pentose (17.40 mg mL-1) and total sugar (18.90 mg mL-1) were from WB as a single substrate. Higher sugar yields were also obtained from combinations involving two and three substrates compared to the single, quadruple and quintet. In most cases, higher amount of each of the sugars were obtained in the solid-state hydrolysis of the substrates than the submerged state. In this study, mixture of CC, WB and GCH yielded higher fermentable sugars on hydrolysis with A. oryzae compared to the individual substrates in solid-state hydrolysis. Substrate combination is therefore recommended to improve the yield of fermentable sugars from lignocellulosic materials and for the sustainability of biofuel production.
Description
Keywords
Lignocellulosic biomass, fermented sugar, substrate combination, fungal cellulase
Citation
Saliu, B.K.; Aleru, F.O.; Idris, A.A.; Mustapha, A.O.; & Iormanger, M. (2022) Effect of Substrate Combination on the Yields of Fermentable Sugars from Lignocellulosic Biomass Hydrolyzed by Fungal Isolates. Journal of Science Technology and Mathematics Education 18 (1): 1-11.