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Updated: May 17, 2026
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Techniques for the Evolution of Robust Pentose-fermenting Yeast for Bioconversion of Lignocellulose to Ethanol
Published on: October 24, 2016
Paddy straw as substrate for ethanol production
1Department of Microbiology, CCS Haryana Agricultural University, Hisar, 125 004 India.
Indian Journal of Microbiology
|October 27, 2012
Summary
Alkali pretreatment of paddy straw effectively removed lignin, enhancing cellulose hydrolysis for biofuel production. Saccharomyces cerevisiae fermentation of the resulting sugars yielded significant ethanol concentrations.
Area of Science:
- Biomass Conversion
- Bioenergy Research
- Agricultural Waste Valorization
Background:
- Paddy straw is an abundant agricultural residue with potential for biofuel production.
- Efficient delignification and hydrolysis are crucial for maximizing sugar release from lignocellulosic biomass.
- Optimizing fermentation conditions is key to achieving high ethanol yields.
Purpose of the Study:
- To investigate the efficacy of sodium hydroxide pretreatment for delignification of paddy straw.
- To determine optimal conditions for cellulase-mediated hydrolysis of pretreated paddy straw.
- To evaluate ethanol production from paddy straw hydrolysate using Saccharomyces cerevisiae.
Main Methods:
- Paddy straw was pretreated with 2% sodium hydroxide at 15 psi for 1 hour.
- Alkali-treated straw was hydrolyzed using cellulase at 50°C for 2 hours.
- Hydrolysate was fermented by Saccharomyces cerevisiae with nutrient supplementation and optimized yeast cell inoculation.
Main Results:
- Sodium hydroxide pretreatment achieved 83% delignification of paddy straw.
- Cellulase hydrolysis released 65% total reducing sugars, with maximum release at 1.5% enzyme loading.
- Fermentation produced 20-30 g L(-1) ethanol, further improved by yeast nitrogen base and 1% yeast cell inoculation.
Conclusions:
- Alkali pretreatment is effective for paddy straw delignification, facilitating subsequent enzymatic hydrolysis.
- Optimized hydrolysis and fermentation processes can efficiently convert paddy straw into bioethanol.
- This study demonstrates a viable pathway for valorizing agricultural waste into valuable biofuels.
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