Dataset Information

Bioprospecting of novel thermostable β-glucosidase from Bacillus subtilis RA10 and its application in biomass hydrolysis.

ABSTRACT:

Background

Saccharification is the most crucial and cost-intensive process in second generation biofuel production. The deficiency of β-glucosidase in commercial enzyme leads to incomplete biomass hydrolysis. The decomposition of biomass at high temperature environments leads us to isolate thermotolerant microbes with β-glucosidase production potential.

Results

A total of 11 isolates were obtained from compost and cow dung samples that were able to grow at 50 °C. On the basis of qualitative and quantitative estimation of β-glucosidase enzyme production, Bacillus subtilis RA10 was selected for further studies. The medium components and growth conditions were optimized and β-glucosidase enzyme production was enhanced up to 19.8-fold. The β-glucosidase from B. subtilis RA10 retained 78% of activity at 80 °C temperature and 68.32% of enzyme activity was stable even at 50 °C after 48 h of incubation. The supplementation of β-glucosidase from B. subtilis RA10 into commercial cellulase enzyme resulted in 1.34-fold higher glucose release. Furthermore, β-glucosidase was also functionally elucidated by cloning and overexpression of full length GH1 family β-glucosidase gene from B. subtilis RA10. The purified protein was characterized as thermostable β-glucosidase enzyme.

Conclusions

The thermostable β-glucosidase enzyme from B. subtilis RA10 would facilitate efficient saccharification of cellulosic biomass into fermentable sugar. Consequently, after saccharification, thermostable β-glucosidase enzyme would be recovered and reused to reduce the cost of overall bioethanol production process.

SUBMITTER: Tiwari R

PROVIDER: S-EPMC5663093 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Publications

Bioprospecting of novel thermostable β-glucosidase from <i>Bacillus subtilis</i> RA10 and its application in biomass hydrolysis.

Tiwari Rameshwar R Singh Puneet Kumar PK Singh Surender S Nain Pawan K S PKS Nain Lata L Shukla Pratyoosh P

Biotechnology for biofuels 20171030

<h4>Background</h4>Saccharification is the most crucial and cost-intensive process in second generation biofuel production. The deficiency of β-glucosidase in commercial enzyme leads to incomplete biomass hydrolysis. The decomposition of biomass at high temperature environments leads us to isolate thermotolerant microbes with β-glucosidase production potential.<h4>Results</h4>A total of 11 isolates were obtained from compost and cow dung samples that were able to grow at 50 °C. On the basis of q ...[more]

PMID: 29093750

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