Cellulomonas sp. Isolated from Termite Gut for Saccharification and Fermentation of Agricultural Biomass

Abstract

Biofuel is an important alternative source of fuel, as many countries are looking to decrease their dependence on fossil fuels. One of the critical steps in biofuel production is the conversion of lignocelluloses to fermentable sugars, and there is need for cheaper and more efficient enzymatic strategies. Consequently, lignocellulase genes from various organisms have been explored. Termites possess varied sets of efficient micro-scale lignocellulose degrading systems. In this study, bacteria that degraded cellulose and xylan were isolated from termite gastrointestinal tract. The isolate was identified as Cellulomonas sp. by 16S rRNA gene sequencing. The bacterial enzymes cellulase and xylanase showed the highest activity at 50 °C and pH 8.0. The agricultural substrates were hydrolyzed by cellulases and xylanases, and more sugar was released from corn stover (18.903+0.65 mM/L) than from rice straw or cotton stalk. After direct hydrolysis and fermentation of agricultural substrates, ethanol (0.425+0.035 g/L) and lactate (0.772+0.075 g/L) were the major end products. Thus, termite gut bacteria can efficiently hydrolyze hemicellulose and cellulose, and these bacteria also have the potential to convert these fermentable sugars into valuable secondary metabolites.

CRUDE CELLULASES FROM SUBTERRANEAN TERMITE EXTRACT (Macrotermes gilvus Hagen) FOR SACCHARIFICATION OF LEAF LITTER AND BIOSOFTENING PROCESS IN SKELETON LEAF CRAFTS MAKING

“…The feedstocks without crude enzyme were used as blanks. Enzyme activity was determined in µmol of glucose produced per minute under test conditions (Afzal et al, 2022;Batool et al, 2018).…”

Unlocking the potential of insect and ruminant host symbionts for recycling of lignocellulosic carbon with a biorefinery approach: a review

“…And the microbial strain is being involved in the of direct conversion of fermentable sugars to secondary metabolites using various agricultural substrate (rice straw, corn stover and cotton stalk). Herein, maximum amount of reducing sugar released was observed to be 18.90 mg/L using corn stover as substrate whereas, direct SSF resulted in 0.425 g/L of ethanol and 0.772 g/L of lactate [ 128 ]. On the other hand, Tsegaye et al [ 61 ] investigated the hydrolytic ability of Bacillus sp.…”

Assessment and Characterization of Xylanolytic Bacteria Isolated from the Gut of Microtermes Obesi for Biomass Pretreatment

“…Universal primers for 16S rRNA gene, 27F(5 ' -AGAGTTTGATCCTGGCTCA-3') and 1492R(5'-ACGGCTACCTTGTTACGACTT-3') were used to amplify 1.5kb 16S rRNA fragment through PCR. Ethanol precipitation method was used to purify PCR products [16]. Puri ed PCR products were sent to "Keck Center for Comparative and Functional Genomics" University of Illinois at Urbana-Champaign, USA.…”