Ethanol production by repeated batch and continuous fermentations of blackstrap molasses using immobilized yeast cells on thin-shell silk cocoons

Publication year: 2011
Source: Applied Energy, In Press, Corrected Proof, Available online 14 June 2011

Anuchit, Rattanapan , Savitree, Limtong , Muenduen, Phisalaphong

A thin-shell silk cocoon (TSC), a residual from the silk industry, is used as a support material for the immobilization of Saccharomyces cerevisiae M30 in ethanol fermentation because of its properties such as high mechanical strength, light weight, biocompatibility and high surface area. In batch fermentation with blackstrap molasses as the main fermentation substrate, an optimal ethanol concentration of 98.6g/L was obtained using a TSC-immobilized cell system at an initial reducing sugar concentration of 240g/L. The ethanol concentration produced by the immobilized cells was 11.5% higher than that produced by the free cells. Ethanol production in five-cycle repeated batch fermentation…

 Highlights: ► Thin-shell silk cocoons for immobilization of Saccharomyces cerevisiae. ► Advantages: high mechanical strength, light weight, biocompatibility and high surface area. ► Enhanced cell stability and ethanol productivity by the immobilization system.