14 



FATTY ACID METABOLISM IN MICROORGANISMS 



7 9 11 13 



Wave length in microns 



15 



Fig. 1.7. Infrared absorption spectra of cyclopropane fatty acids. 

 (1) DL-ira?j5-ll,12-Methyleneoctadecanoic acid. (2) DL-^ran5-9,10- 

 Methyleneoctadecanoic acid. (3) Lactobacillic acid from L. casei. 



foetida, is subjected to controlled catalytic hydrogenation 

 (20, 22). The cis configuration for dihydrosterculic acid 

 appeared likely, since low temperature catalytic hydrogena- 

 tion of double bonds favors cis addition of hydrogen. 



The chemical structure of sterculic acid and location of 

 the three-membered ring is based on the reactions which are 

 illustrated on Fig. 1.8 (22). 



Since cis-trans isomers in the series of long-chain cyclopro- 

 pane fatty acids differ little in the very physical properties 



