Sustainable co-valorization of seawater pretreated banana pseudostem and dairy wastewater for bioethanol production

Abstract

Simultaneous saccharification and fermentation (SSF) of ethanol production was optimized using banana pseudostem (BP) and dairy wastewater in this study. The kinetics of Saccharomyces cerevisiae BY4743 cell growth and bioethanol production under optimized medium conditions in dairy wastewater (DWW-SSF), pure water (PW-SSF), and a standard bioethanol fermentation medium modified with BP (mYPD-SSF) were comparatively investigated. The optimized SSF process showed DWW-SSF had bioethanol concentration of 33.93 g/L that is 38% and 34% highest in bioethanol concentration in comparison to the PW-SSF (24.67 g/L) and mYPD-SSF (25.28 g/L) experiments. For the kinetic assessment, the highest maximum specific growth rate (µ max ) of 0.60 h -1 was obtained with PW-SSF, followed by DWW-SSF (0.34 h -1 ) and mYPD-SSF (0.27 h -1 ) whereas the DWW-SSF process led to the highest maximum potential ethanol concentration (P m ) of 28.68 g/L but lower P m of 23.78 g/L and 23.09 g/L were obtained for the mYPD-SSF and PW-SSF processes respectively. This study highlights the potential of waste-based lignocellulosic biofuel production through SSF bioprocesses, offering opportunities to reduce the reliance on costly fermentation medium components and finite water, while addressing industrial wastes.