PANTOTHENIC ACID 



Pantothenyl alcohol, N-pantoylethanolamine, N-pantoylallylamine, 

 N-pantoyl-w-propylamine, N-pantoylethylamine and N-pantoylglycine 

 also inhibited the growth of micro-organisms for which pantothenic 

 acid is essential, and the inhibition was competitive.^^ The anti- 

 bacterial indices of pantothenyl alcohol and N-pantoyl-4-amino-2- 

 butanol, the most potent of these inhibitors, were : *^ for L. mesen- 

 teroides, 700 and 600 ; for L. helveticus, 100,000 and 20,000 ; for 

 L. arabinosus, 50,000 and 10,000 ; and for L. fermenti, 200,000. 

 All compounds were tested in the racemic form, but it was shown that 

 pantothenyl alcohol derived from the (—) -lactone was more active 

 than the isomer from the ( + )-lactone.^^ Growth inhibition by panto- 

 thenyl alcohol did not run parallel with pantoyltaurine inhibition and 

 it is assumed that the modes of action of the two compounds are 

 different. 



Subsequently, W. Shive and E. E. Snell*^ prepared and tested 

 other pantoyl derivatives and obtained the following antibacterial 

 indices, using Leuconostoc mesenteroides as test-organism : 



Rather different values were obtained with L. arabinosus and L. 

 helveticus in many instances. Pantoyltaurine and N-pantoyl-w-butyl- 

 amine also interfered with the utilisation of pantothenic acid by 

 Pseudomonas spp.^* 



D. W. Woolley and M. L. Collyer *^ prepared phenylpantothenone 

 (N-pantoylaminoethyl phenyl ketone) and showed that it inhibited 

 bacterial growth and that the inhibition was reversed by pantothenic 

 acid. This compound, therefore, behaved like pantoyltaurine, inhibi- 

 tion being competitive. Methylpantothenone (N-pantoylaminoethyl 

 methyl ketone) exhibited growth-inhibitory properties, but the inhibi- 

 tion was not reversed by pantothenic acid. 



The antagonistic effect of pantothenic acid towards phenyl panto- 

 thenone was only exhibited with micro-organisms for which the 



400 



