C-13-PATTERN OF NATURAL GLYCEROL - ORIGIN AND PRACTICAL IMPORTANCE

The average delta(13)C-value of glycerol from plant origin is 4-5 part s per thousand more negative than that of carbohydrates from the same source. This depletion is exclusively dealing with position C-1 of the molecule. This is also observed for glycerol from other natural sourc es, although to a smaller extent, while synthetic glycerol shows a sta tistical C-13-pattern. On the basis of these data an illegal addition of glycerol to wine should be detectable. In fermentations of glucose with yeast the extent of the depletion in position C-1 of glycerol pro ved to be reciprocal to its yield. Furthermore a total carbon and isot ope balance showed that the depletion of glycerol is a compensation fo r small C-13-enrichments in the corresponding positions of main produc ts. An isotope effect on the aldolase reaction and a noncomplete equil ibration of the triose phosphates are discussed as main reasons for th ese findings.