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Updated: Jul 5, 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
Enzymatic hydrolysis optimization to ethanol production by simultaneous saccharification and fermentation
Mariana Peñuela Vásquez1, Juliana Nascimento C da Silva, Maurício Bezerra de Souza
1Centro de Tecnologia-Bloco E, Escola de Química-Universidade Federal do Rio de Janeiro, CEP 21.949-900, Rio de Janeiro-RJ, Brasil.
Applied Biochemistry and Biotechnology
|May 15, 2008
Summary
Agro-industrial waste cellulignin can be converted to glucose and then fermented into ethanol. Optimized enzymatic hydrolysis and fermentation achieved significant ethanol yields, comparable to conventional methods.
Area of Science:
- Biotechnology
- Biochemical Engineering
- Renewable Energy
Background:
- Agro-industrial wastes like sugarcane bagasse are abundant resources.
- Cellulignin, derived from acid hydrolysis of sugarcane bagasse, presents a potential feedstock for biofuels.
- Efficient conversion of cellulignin into valuable products is crucial for sustainable practices.
Purpose of the Study:
- To optimize the enzymatic hydrolysis of the cellulose component of cellulignin.
- To investigate the subsequent fermentation of the resulting glucose to ethanol using Saccharomyces cerevisiae.
- To identify optimal conditions for maximizing both cellulose conversion and glucose yield.
Main Methods:
- Response surface methodology was employed to optimize enzymatic hydrolysis.
- Key variables included pH, enzyme loading, solid percentage, and temperature.
- The desirability function was used to find optimal conditions balancing glucose conversion and concentration.
Main Results:
- Optimal conditions for cellulose to glucose conversion were determined (43°C, 2% solids, 24.4 FPU/g).
- Optimal conditions for glucose concentration were found (47°C, 10% solids, 25.6 FPU/g).
- Fermentation of the optimized hydrolysate yielded 30.0 g/L ethanol in 10 hours with 3.0 g/L x h productivity.
Conclusions:
- Enzymatic hydrolysis and fermentation of cellulignin are viable routes for ethanol production.
- Optimized conditions significantly enhance glucose yield and subsequent ethanol production.
- This process offers a promising alternative to conventional ethanol production from sugarcane juice.
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