Ethanol production from sweet sorghum by Saccharomyces cerevisiae DBKKUY-53 immobilized on alginate-loofah matrices

Nuanpeng, SunanThanonkeo, SudaratKlanrit, PreekamolThanonkeo, Pornthap

Abstract Ethanol production from sweet sorghum juice (SSJ) using the thermotolerant Saccharomyces cerevisiae strain DBKKUY-53 immobilized in an alginate-loofah matrix (ALM) was successfully developed. As found in this study, an ALM with dimensions of 20 × 20 × 5 mm3 is effective for cell immobilization due to its compact structure and long-term stability. The ALM-immobilized cell system exhibited greater ethanol production efficiency than the freely suspended cell system. By using a central composite design (CCD), the optimum conditions for ethanol production from SSJ by ALM-immobilized cells were determined. The maximum ethanol concentration and volumetric ethanol productivity obtained using ALM-immobilized cells under the optimal conditions were 97.54 g/L and 1.36 g/L h, respectively. The use of the ALM-immobilized cells was successful for at least six consecutive batches (360 h) without any loss of ethanol production efficiency, suggesting their potential application in industrial ethanol production.

1. Saccharomyces cerevisiae
2. Thermotolerant yeast
3. Ethanol production
4. Alginate-loofah-matrix
5. Sweet sorghum