A Study On Asymmetric Reduction Of 2-Acetyl Ethyl Heptanoate By Yeast Cells

Single enantionmer pharmaceuticals,agrochemicals and other fine chemical are more and more important to people's living and industrial.So to synthesis the key chiral buiding blocks for these single enantionmer chemical products has become one of the most important and hot fields.Baker's yeast is rich in oxidoreductase,it's one of the important research methods to baker's yeast reduction potential of the hands of carbonyl compounds.The asymmetric reduction by yeast cells in aqueous phase was investigated when 2-acetyl ethyl heptanoate was chosen as the model substrate.Because no commercial 2-acetyl ethyl heptanoate and ethyl 2-(1-hydroxyethyl) heptanoate is available in market,so they must be synthesized as standards before other research works.A determined method of quantitative analysis of the substrate and the product was established by gas chromatography.The main factors including the flow rate of carrier gas and the column temperature to influence the separation were also discussed.The optimum separation condition was established,which made the following research works easy.The asymmetric reduction of 2-acetyl ethyl heptanoate by yeast cells was investigated respectively in this work.The effects of reaction conditions,such as initial substrate concentration,cell concentration,reaction pH and temperature,initial glucose concentration, and reaction time were investigated by orthogonal experiment.The conversion was improved by increasing the concentration of yeast cells.The optimum reaction was 30℃, pH7.0,cell concentration of 200 g/L,initial glucose concentration of 10 g/L,substrate concentration of 10mmol/L,reaction time 24h,the yeast MaLi with high catalytic activity.when conversion rates are relatively high compared glucose,methanol,ethanol,isopropanol and several auxiliary at the end of glycerol,glucose as best supporting substrate;glucose concentration of 10g/L conversion rate better.Aerobic training at the end of training than anaerobic conversion rate higher;shocks under the conditions of reduction than the static response to a higher conversion rate.In batches to join at the end of the results better than the one-time accession to the results.