COMPOSITION OF NATURAL FATS AND OILS 191 



Hilditch group, "'""^ including Lovern/^^ by Japanese workers,"'''^''* 

 and by others. ^"-^^ 



The fat from dolphins and porpoises, as well as from other members of 

 the Delphinidae, is unique in containing a considerable proportion of the 

 branched-chain compound, isovaleric acid. The amount varies in dif- 

 ferent portions of the body, being highest in the head (particularly the jaw) 

 and blubber, and being absent from the liver, lungs, and heart. Lovern^*^ 

 has reported that a sample of the jaw fat of the porpoise {Phocaena com- 

 munis) contained 25.3% of isovaleric acid, which corresponds to a molar 

 percentage of 44.7%. Isovaleric acid is likewise present in the head fat of 

 another marine mammal, the white whale {Delphinapterus leucas),^^^ to the 

 extent of 25.1%. 



A\Tiale oil contains sizable amounts of Cm and C22 unsaturated acids 

 and is a typical marine fat. The samples obtained from Arctic regions 

 which have been investigated by C. W. Moore and C. H. Clarke, accord- 

 ing to Armstrong and Allan, "^ have a higher unsaturation (and a lower 

 proportion of saturated acids) than the oil obtained from the Antarc- 



•j-JQ 176,177,183,184 



(6) Composition of Fats from Land AnimMs. With the increasing com- 

 plexity of the animals, the component fats become simpler. The trans- 

 formation is a gradual one. In the case of the amphibia and reptiles, there 

 is little change in the total unsaturated acids as compared with those of the 

 aquatic forms, but a marked reduction in acids of the C22, C2n, and Cie 

 series, with a proportional increase in the C18 unsaturated acids. ^**~"' 



A considerable amount of experimental work has been carried out on the 

 composition of the fat of birds. Only small amounts of C20-C22 un- 

 saturated acids were found to be present in the fats from light Sussex hens, 

 while palmitic acid comprised about 25% and stearic acid 7% of the total 



>" T. P. Hilditch and A. Houlbrooke, Analyst, 53, 246-257 (1928). 



'"* T. P. Hilditch and J. A. Lovern, /. Soc. Chem. Ind., J^^, 105-11 IT (1928). 



"» T. P. Hilditch and J. A. Lovern, J. Soc. Chem. Ind., 48, 359-365T (1929). 



"^ T. P. Hilditch and J. A. Lovern, /. Soc. Chem. Ind., 48, 365-368T (1929). 



1" M. Tsujimoto, Chem. Umschau Fette Ole Wachse Harze, 39, 50-52 (1932); Chem. 

 Abst., 26, 3126 (1932). 



"» M. Tsujimoto, J. Soc. Chem. Ind., 51, 317-323T (1932). 



"9 E. Andre and A. Bloch, Compt. rend., 195, 627-629 (1932). 



180 T. H. Wang and C. H. Kan, /. Chinese Chem. Soc, 4, 393-401 (1936). 



1" J. A. Lovern, Biochem. J., 28, 394-402 (1934). 



1'* N. V. Williams and N. Y. Maslov, Schnften Zentr. Forsch.-Inst. Lebensmiiielchem. 

 U. S. S. R., 4, 150-156 (1935); Cheyn. Abst., 30, 4707 (1936). 



»" L Tveraaen and A. Klem, Hvalr&dets Skrifter. ,No. 11, Kr. 8, 5^8 (1935). 



"« T. P. Hilditch and J. T. Tereleski, J. Soc. Chem. Ind., 56, 315-322T (1937). 



'« T. G. Green and T. P. Hilditch, Biochem. J., 32, 681-686 (1938). 



•«« T. P. Hilditch and K. S. Murti, /. Soc. Chem. Ind., 58, 351-353T (1939). 



18' T. P. Hilditch and H. Paul, Biochem. J., 31, 227-228 (1937). 



188 E. Klenk, Z. physiol. Chem., 221, 259-263, 264-270 (1933). 



"9 E. Klenk, F. Ditt, and W. Diebold, Z. physiol Chem., 232, 54-63 (1935). 



