460 THIAMINE 



exercising an antithiamine activity in fish and other sea food are thiamin- 

 ases. Some reports have been published on plants that show an antithiamine 

 activity, but it has not yet been established whether these plants contain 

 antithiamines or thiaminases. 



Weswig et al}^ found that ferns (Pteris aquilina) have an antagonistic 

 activity against thiamine. Horses fed a fodder containing large amounts of 

 ferns show signs of polyneuritis and can be cured by thiamine. 



Bhagvat and Devi^^ found antithiamine activity in extracts from rice 

 polishings, beans {Phaseolus radiatus), mustard seed, etc. 



Somogyi,"^ in a comprehensive investigation of antithiamine factors, not 

 only confirmed their existence in carp viscera but also demonstrated that 

 extracts of organs of warm-blooded animals (rabbits or chicks) have a 

 considerable antithiamine activity. The greatest activity was observed with 

 extracts of heart and spleen. Liver extract show^ed a moderate activity, 

 whereas the extract of intestines of warm-blooded animals had only a slight 

 action in contrast to that of carp extracts. The active principles obtained 

 from warm-blooded animals are thermolabile and do not dialyze, so prob- 

 ably they contain thiaminases. 



X. Effects of Deficiency 



B. C. P. JANSEN 



A. IN MICROORGANISMS 



Of the effects of thiamine deficiency on microorganisms, not much is 

 known. The microorganisms that cannot synthesize thiamine can be used 

 for the microbiological estimation of thiamine. 



B. IN ANIMALS 



As far back as 1892 Eykman published his results about the signs of 

 nerve degeneration in fowls that were fed with thiamine-poor polished rice. 

 From this work started the whole vitamin research. Thus the degeneration 

 of the peripheral nerves was the first pathological sj'mptom noted. Eykman 

 stained the nerves with Marchi solution, and he thought that in the poly- 

 neuritic animals the axis of the nerves was degenerated. Half a century 

 afterward in an extensive examination of the peripheral nerve fibers in 



23 p. H. Weswig, A. M. Freed, and J. R. Haag, J. Biol. Chem. 165, 737 (1946). 

 ^-i K. Bhagvat and P. Devi, Indiayi J. Med. Research 32, 131 (1944). 

 25 J. G. Somogyi, Die Antianeurin-factoren. Hans Huber, Bern, 1952. 



