CAROTENOIDS 



to conclude that there is " good reason for admitting " that spirillo- 

 xanthin is identical with Karrer's rhodoviolascin. Data on the properties 

 of bacterial carotenoids and their qualitative distribution are recorded 

 in Tables 19, 20. 



Table 19. — Properties of Bacterial Carotenoids 



Heavy figures relate to references below . 



* The probable identity of these with neurosporene cannot be ignored. 



t These may be identical. 



X May be identical with e-carotene. 



§ May be identical with lycopene. 

 *t a-Bacteriopurpurin is probably one of Karrer's rhodo-carotenoids. 

 tt 3-Bacteriopurpurin is probably identical with rhodoviolascin. 



REFERENCES TO TABLE 19. 



1. Chargaff, E., and Dieryck, J. (1932), Naturwiss., 20, 872. 



2. Takeda, Y., and Ohta, T. (1941), Hoppe-Seyl. Z., 268, 1. 



3. SOBIN, B., and Stahly, G. L. (1942), J. Bact., 44, 265. 



4. Karrer, p., and Solmssen, U. (1935), Helv. Chim. Acta, 18, 25, 1306. 



5. Karrer, P., and Solmssen, U., and Koenig, H. (1938), Helv. Chim. Acta, 21, 454. 



6. Fetter, H. F. M. (1931), Amsterdam Akad. Wiss., 34, No. 10. 



7. Lederer, E. (1938), Bull. Soc. Chim. Biol, 20, 611. 



8. Takeda, Y., and Ohta, T. (1939), Hoppe-Seyl. Z., 262, 168. 



9. Turian, G. (1950), Arch. Set. Soc. Phys. Hist. Nat. Geneve, 3, 79. 

 10. Turian, G. (1950), Helv. Chim. Acta, 33, 1303. 



Volk and Pennington ^ ° ^ detected [3-carotene, rhodopin, rhodovibrin 

 and probably rhodoviolascin (spirilloxanthin) in Rhodomicrobium 

 vannielii ; m-isomers of rhodopin and rhodovibrin are also reported, 

 but complete evidence of their identification is still lacking. 



122 



