NUTRITIONAL FACTORS OF DOUBTFUL STATUS 715 



is also effective in preventing the inhibition, but ( + ) -inositol, scyllitol 

 and other related compounds are inactive. 



Chargaff et al. 96 found that meso-inositol is able to prevent the meta- 

 phase arrest and tumor formation induced in Allium Cepa by either 

 colchicine or y-hexachlorocyclohexane, first observed by Nybom and 

 Knutsson. 97 Meso-inositol appears to be specific in producing this effect; 

 other related compounds were inactive. 



It was recently reported 98 that y-hexachlorocyclohexane, after an in- 

 cubation period of 16 hours, completely inhibited the enzymatic activity 

 of a sample of purified pancreatic a-amylase which had been shown to 

 have a relatively high inositol content. The inhibition was competitively 

 prevented by the addition of meso-inositol. Fischer and Bernfeld " were 

 not able to repeat this work, and suggested that the inositol-containing 

 amylase was only partially purified. 



Meillon 10 ° observed that the blood of rabbits injected with y-hexa- 

 chlorocyclohexane was toxic for certain blood-sucking anthropods and 

 that this toxicity was not reversed by injections of inositol. Schopfer 95 

 found that either the toxicity of the inhibitor or the reversing action of 

 meso-inositol was negligible or inconsistent in many fungi. He suggested 

 that these inconsistencies may be due to the biosynthesis of inositol by 

 these organisms. 



Other studies have indicated that S-hexachlorocyclohexane is more 

 toxic than the y-isomer for the ciliate Glaucoma piriformis, 101 for the 

 eggs of sea urchins, 102 and for many bacteria. 103 In none of these cases 

 was meso-inositol effective in preventing the toxicity. 



In view of all the above experiments, it seems reasonable to conclude 

 that the toxicity of y-hexachlorocyclohexane for various organisms is not 

 dependent on a single mechanism. Even though the y-isomer may in some 

 cases interfere with enzymatic reactions involving meso-inositol, 

 there are apparently interrelationships other than these which are 

 involved. 



Carter and his co-workers 104 found an interesting relationship between 

 streptomycin and lipositol, a phospholipide containing 16 per cent inositol 

 in a combined form. Soy bean lipositol, as well as preparations from 

 brain infusion, prevented the antibacterial action of streptomycin on 

 Eberthella typhosa and Staphylococcus aureus. Since there is present in 

 lipositol an inositol-galactose structure which bears some resemblance to 

 the streptomycin molecule, the authors suggested the possibility of a 

 metabolite-antimetabolite relationship. It has also been observed 105 that 

 lipositol is slightly active in replacing streptomycin for streptomycin- 

 requiring mutants of Escherichia coli. 



