Using bakers’ yeast

Optically pure a, . (R)-3-hydroxybutanoates can be obtained by alcoholysis of poly-(R)-3-hydroxybutanoate, a fermentation product of fructose by Alcaligones eutrophus.4 (S)-Ethyl 3-hydroxybutanoate in 84-87% ee can be synthesized in 57-67% yield on a decagram-scale by an Organic Syntheses procedure6 using bakers yeast reduction of ethyl 3-oxobutanoate with the aid of sucrose.7 In order to obtain enantioselectivity as high as 95-97% ee, the substrate concentration should be kept below 1 g/L.6... 

Asymmetric Reduction of Ketones Using Bakers Yeast... 

Asymmetric reduction of a,/l-unsaturated aldehydes with transition metal catalysts has not yet proven ready for widespread industrial application. One area, namely the chiral reduction of enals to yield chiral alcohols using bakers yeast has been... 

Knowledge of the life cycle and genetics of Saccharomyces cerevisiae has been obtained using strains selected for their suitability for analysis. Such strains, often termed laboratory or genetic , have their origins in commercially used bakers yeast. 

Resolution of o and m-substituted benzylalcohol chromium tricarbonyls by reduction of the corresponding aldehydes using bakers yeast has been achieved. The regioselective complexation of 1,2 9,10-dibenzo[2.2]paracyclophane-1,9-diene with Cr(CX))3 has been described. The diasteteoselective nuclec hilic 1,2-addition reactions of N-benzylidene-1--methylaniline chromium tricarbonyl has been achieved. A range of hetetobimetallic complexes of substituted mesitylene chromium iricarbonyls has been prepared. ... 

Yeast extracts/HVP — Normally one uses bakers yeasts or extracts thereof in seasonings. They serve both as a flavorant and bulking agent HVPs are typically used in meaty flavorings. These materials will add some flavor of their own typically considered savory or meaty in character. They also contribute flavor enhancers—MSG (HVP and yeast extracts) and 5 -nucleo-tides (yeast extracts). 

It was shown that the selective bioreduction of diketones 19 to yield mono-keto-alcohols 20 could be achieved using Bakers yeast as shown in Scheme 6.7 [14]. 

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