Development of a Novel Co-Culture-Cell Bioreactor for Bioethanol Production from Rice Straw

Demanding of alternative energy sources has received attention due to petroleum shortage recently. Bioethanol is one of the most cost-effective products with a clean environment, sustainable regeneration benefits. There were more than 1600 thousand tons of rice straw agricultural wastes produced in Taiwan every year. Fermentative production of ethanol from renewable resources has prompted interest in immobilized microbial cell systems for conversion of biomass to fuels. Bioethanol production from rice straw not only regenerates the agriculture waste into bioenergy, but also solves the problem of environmental pollution by rice straw burning. For the last two decades, ethanol production from agriculture waste by the coimmobilized- cell system has been studied extensively. An efficient bioreactor is the key for a profitable co-immobilized aerobic/anaerobic mixed process of bioethanol production from lignocellulosic biomass. The aim of this study is to develop a novel bioreactor with space for both aerobic and anaerobic reaction, and investigate its feasibility to co-immobilize saccharification strains (T. reesei & A. niger) and fermentation strains (Z. mobilis) for bioethanol production through simultaneous saccharification and fermentation of acid-pretreated rice straw using calcium-alginate beads as the immobilization carrier. This proposal is a continuation of a National Science Council project「New Energy Source form Agricultural Waste-Bioethanol production by Co-cultured-cell system and a Novel Bioreactor」. We have great harvest in the project including (1) induction and selection of high-efficiency cellulose or starch-degrading or -saccharifying microbes as T. reesei & A. niger, Z. mobilis, (2) establishment and evaluation of a suspension and immobilization cultured system, (3) setup and work of the co-immobilized-cell system, (4) practical application of co-immobilized-cell system, (5) investigation and establishment of the optimal co-immobilization cultural conditions, and (6) development and feasibility investigation of the novel co-cultured-cell bioreactor with space for both aerobic and anaerobic reaction. This year, the second year of this two-year project, we will investigate the optimal production condition and the operation model by this technology platform. The new designed bioreactor will be able to biotransform agricultural waste to ethanol fermentation broth in high-yield and quickly. The final purpose is to develop a new co-immobilized-cell system that could deal agricultural waste (rice straw) rapidly, and transform them into bioethanol simultaneously.

Project ID:PB10108-2822
External Project ID:NSC101-2221-E182-035