"Simple biocatalysts" are innovative biocatalysts which can completely convert substrates to products only by the thermo-stable enzymes expressed in bacterial cells. This biocatalyst is expected for effective bio-conversion because no by-products are generated by heat-treated host metabolic enzymes. We aimed to construct simple biocatalysts using psychrophilic bacterial cells as an effective bio-conversion tool which can use abundant mesophilic and thermophilic enzyme for various bio-conversion. In this seminar, I will talk about the bio-conversion from glycerol to 3-hydroxypropionaldehyde and 1,3-propanediol by simple biocatalysts.

In supercritical water gasification of biomass, lignin blocks biomass from gasification. In this study, we investigated the decomposition of glucose with guaiacol, model compound of lignin, in supercritical water. The pressure was kept constant at 25 MPa. Interactive effect made char production from glucose at subcritical area and it from guaiacol at supercritical area decreased.

In this study, effects of base catalyst on subcritical water gasification of glucose, which was used as a model compound for cellulose, were explored using a tubular flow reactor. NaOH represented base catalyst, which was added to neutralize acidic products released by decomposition of glucose. Concentration of NaOH was varied from 0.00M (non-catalytic) to 0.05 M. The experiments were conducted with residence time of 5, 20 and 60 s at temperature and pressure of 350 ℃, 25 MPa respectively. Gas, liquid, and solid products were observed to confirm the carbon balance in the system. Composition of final product is determined and yield of glucose, fructose, 5-HMF, furfural, TOC (including acidic and other decomposition products), char, and gas were quantified to aim for kinetics calculation. First order was assumed for each reaction to consider kinetic parameters (k) and further to determine its Arrhenius behavior. All the results were discussed to elucidate the effect of base catalyst on supercritical water gasification of glucose.