ISSN:
1432-0614
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Summary From six unsaturated fatty acid auxotrophs (Ufa mutants) of the oleaginous yeast Apiotrichum curvatum blocked in the conversion of stearic to oleic acid, were isolated revertants able to grow in the absence of unsaturated fatty acids, in a search for strains that can produce cocoa butter equivalents. A broad range in the percentage of saturated fatty acids (%SFA) was observed in the lipids of individual revertants (varying from 27%–86% SFA), compared with the wild-type (44% SFA). Further analysis of fatty acid composition indicated that: (i) not all six Ufa mutants had the same genetic background and (ii) one specific Ufa mutation could be reverted in more than one way. Revertants that produced lipids with a %SFA〉56%, were examined further. These strains were cultivated for 50 generations and half of them produced lipids with high %SFA after that time and were defined as stable. The viability of revertant strains with extremely high %SFA (〉80%) may be explained by our finding that polar lipids, which are part of yeast membranes, contained much more polyunsaturated fatty acids and a significantly lower %SFA than neutral (storage) lipids. One revertant (R25.75) was selected that was able to produce lipids in whey permeate at a rate comparable with wild-type A. curvatum and with a fatty acid composition and congelation curve comparable with cocoa butter.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00176521
