Microbial reduction using ethanol as an energy source

点击翻译按钮获取中文摘要

The microbial reduction of prochiral ketones has been recognaized as a useful technique to prepare a chiral secondary alcohols. Recently, a new procedure for the baker's yeast-mediated bioreduction using ethanol instead of sugar as the energy source was developed. This research is to study the microbial reduction using ethanol as the energy source and to study the relation between culitivation conditions and the reduction ability.1.Screening of microbials using ethanol as an energy source for NAD(P)H regneration coupled with a bioreductionMany of the tested strains of years use ethanol and/or acetate as an energy source for NAD(P)H regneration coupled with a bioreduction in the same manner as glucose. Then, molds use only glucose as the energy source but ethanol or acetate. On the other hand, some of bacterias use ethanol effectively but glucose.A scheme for NAD(P)H regeneration from the corresponding oxidezed from through the oxidative pathway of ethanol in yeast cells was studied. THe results suggested tha NADH was regenerated through alcoholic oxidation into acetate and NADPH through acetate oxidation into carbon cioxide.2.Relationship between the ability using ethanol as energy sourcet for NAD(P)H regeneration and the culture condition on oxygen absorption rate.Yeasts, Saccharomysex cerevisiae HUT 7099, cultured under more anaerobic conditions had the lower ablity using ethanol as energy source for NAD(P)H regeneration. The reason was related to lower activity of aldehyde dehydrogenase though the activity of alcohol dehydrogenase was not influensed by such culture conditions.