II. CHEMISTRY 



559 



Table I"* contains the relevant data for the various l)iotin isomers, d- 

 Biotinol,"^ the alcohol analog of biotin, is inactive for Lactobacillus arabino- 

 sus, L. casei, and Saccharomyccs ccrevisiae but is fully as effective as d-biotin 

 in curing egg-white-induced biotin deficiency in the rat. Excretion studies 

 in rats and man showed that biotinol after oral or intramuscular adminis- 

 tration is effectively converted to biotin."^ 



Filtration of bacteriological culture media through Seitz filters should 

 take in consideration the possibility that such Seitz filters may release 

 biotin originating from previous contamination, ^^'^ 



It is of interest that, of the two racemic diastereoisomers of the oxygen 



TABLE I 

 Specific Activity of Biotin Isomers"* 



analog of biotin, only one, rf^oxybiotin,'2^ possesses appreciable activity 

 (Table II). The other, d/-epioxybiotin, is practically inactive. Its very 

 slight activity for Lactobacillus arabinosus (0.1% that of oxybiotin) is 

 probably caused by oxybiotin as a contaminant.'^' It is to be expected 

 that, as with biotin, only one of the optically active forms of oxybiotin is 



'•< R. J. Williams, R. E. Eakin, E. Beerstecher, Jr., and W. Shive, The Biochemistry 

 of B Vitamins. Reinhold Publishing Corp., New York, 1950. 



"* G. A. Emerson, J. Biol. Chem. 157, 127 (1945). 



'16 W. H. Ott, /. Biol. Chem. 157, 131 (1945). 



"7 J. L. Stokes and M. Gunness, J. Biol. Chem. 157, 121 (1945). 



"8 M. W. Goldberg and L. H. Sternbach, U. S. Pat. 2,489,237. 



I's L. Drekter, J. Scheiner, E. DeRitter, and S. H. Rubin, Proc. Soc. Exptl. Biol. 

 Med. 78, 381 (1951). 



1-'' S. N. Basu and R. G. Bose, Nature 165, 851 (1950). 



121 K. Hofmann and A. E. Axelrod, Arch. Biochem. 11, 375 (1946). 



