Green Conversion of Banana Pseudostem to Bioethanol: Integrating Pretreatment Innovations and Microbial Immobilization

Abstract

The banana pseudostem (BPS), which is a lignocellulosic agricultural waste, can be a renewable sustainable plant-based fuel. BPS contains cellulose and hemicellulose which have significant potential to be converted into biofuels, especially bioethanol. The aim of this review is to outline recent advances in the production of bioethanol from BPS and highlight the application of liquid hot water (LHW) pretreatment, microbes in the multi-step fermentation process and prospects of the microbial immobilization as a key breakthrough in the future of biofuel technology. The fermentation process is essential and involves microorganisms like Aspergillus, Trichoderma, Saccharomyces cerevisiae, Candida molischiana, Zymomonas mobilis and Kluyveromyces marxianus which convert the carbohydrate to bioethanol. In this review, a new approach of combining LHW pretreatment and the microbial immobilization technology to obtain bioethanol from BPS is provided. The method is a departure from the previous studies, which have been carried out only on pretreatment or fermentation. Rather, it is concerned with the cooperative potential of eco-friendly biomass processing with advanced microbial systems to enhance the efficiency and stability of bioethanol and potentially enable continuous processing. This comprehensive solution offers a sustainable and scalable way to transform BPS waste into renewable energy, moving towards the concept of a circular bioeconomy. Keywords: Banana pseudostem, bioethanol, liquid hot water pretreatment, microbial immobilization.