HYDROCARBONS 325 



dioxide under certain conditions. Langdon and Bloch^*^ reported that 

 this highly unsaturated hj^drocarbon is readily absorbed from the intestine 

 of the rat, and that 5 to 10% can be recovered unchanged from the tissues. 

 Yamasaki'^^ observed that, in rabbits, squalene is oxidized to a small 

 extent to succinic and levulinic acids. Some is eliminated by way of the 

 kidney and gastrointestinal tract, and another small part may be stored for 

 over three months, principally in the liver. Yamasaki postulates that the 

 oxidation of squalene proceeds ^\ith difficulty. This may also be true of 

 other aliphatic hydrocarbons. The diffusion of this compound through 

 animal cells would appear to be very slow. 



(6) Unsaturated Hydrocarbons Other Than Squalene. Several unsatu- 

 rated aliphatic hydrocarbons, which have been isolated from natural 

 sources, have been reported, both in li\'er oils and in plant lipids. Thus, 

 gadusene, CisHso, which was separated from wheat-germ oil by Drummond 

 et al.,^^* is presumably the same compound isolated earher by Tsuji- 

 moto'^ from the liver oil of the Japanese ishinagi {Stereolepis ishinagi). 

 Gadusene has likewise been sho\Mi to comprise an important proportion 

 of the unsaponifiable fraction of rice-germ oil, soybean oil, and of some 

 fish liver oils.^^^ Oleastane, C21H36, was reported by Sani'^^ to occur 

 in the olive, while zamene, CisHse, has been prepared from the liver 

 oil of the basking shark (Cetorhinus maximus) . ^^^ According to Marcelet, ^^* 

 hypogene, CisHso, and arachidene, C19H38, occur in the non-saponifiable 

 fraction of peanut oil. The following unsaturated h3drocarbons have 

 likewise been identified in ohve oils: oleatridecadiene (C13H24); oleahexa- 

 decadiene (CieHso) ; oleanonadecadiene (CseHie) ; oleatricosatriene (C23H42) ; 

 and oleaoctacosatetraene (C28H5o).^^^ Two saturated hydrocarbons were 

 likewise reported from the same source, namely oleatetracosane (C24HB0) 

 and oleahexacosane (C26H54). 



c. The Metabolism of Aliphatic Hydrocarbons and of Related Com- 

 pounds. The most extensive study of the origin of the hydrocarbons and 

 of the several related compounds in the plant waxes was carried out by 

 Chibnall, and is summarized in the paper of Chibnall and Piper. ^-- The 

 salient suggestions for the origin of the several components of the waxes in 

 their scheme are as follows: 



'«^ S. Yamasaki, /. Biochem. {Japan), 37, 99-10-4 (1950). 



'" J. C. Drummond, E. Singer, and R. J. MacWalter, Biochem. J., 29, 456^71 (1935). 



•65 M. Tsujimoto, Bull. Chem. Soc. Japan, 6, 2:^7-239 (19:31); Chem. Abst., 26, 612-613 

 (1932). 



i« Z. Nakamiya, Sci. Papers Inst. Phys. Chem. Research, Tokyo, 28, 16-26 (1935). 



1" G. Sani, Atti accad. naz. Lincei, 12, 238-242 (1950). 



i«« H. Marcelet, Compt. rend., 202, 1809-1811 (1936). 



"' H. Marcelet, BuU. soc. chim. [5], 3, 1156-1160; 2055-2057 (1936); Compt. rend., 

 ^0^, 867-869 (1936). 



