Isolation of a crystalline toxic factor from agenized wheat flour / by P.N. Campbell and Sir Edward Mellanby.

  • Campbell, P. N. (Peter Nelson)
Date:
[1950?]
Catalogue details

Licence: In copyright

Credit: Isolation of a crystalline toxic factor from agenized wheat flour / by P.N. Campbell and Sir Edward Mellanby. Source: Wellcome Collection.

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    {Reprinted from Nature, Vol. 165, p. 345, March 4, 1950) ISOLATION OF A CRYSTALLINE TOXIC FACTOR FROM AGENIZED WHEAT FLOUR By Dr. P. N. CAMPBELL, Dr. T. S. WORK and Sir EDWARD MELLANBY, G.B.E., K.C.B., F.R.S. National Institute for Medical Research and Nutrition Building, Mill Hill, London, M.W.7 IN 1946 it was established by Mellanby’ that dogs fed a diet rich in commercially ‘improved’ (nitrogen trichloride-treated) flour were subject to epileptiform fits ; similar fits were never seen in control animals fed on untreated flour. Mellanby concluded that the treatment of flour with nitrogen trichloride gave rise to a toxic factor which was responsible for the condition in dogs well known in Great Britain as ‘canine hysteria’ and in .the United States as ‘running fits’. A large proportion of the flour milled in Britain and used for bread-making is ‘improved’ by treat¬ ment with nitrogen trichloride and is known com¬ mercially as ‘agenized’ flour. The observation that this flour was toxic to dogs was followed by a demon¬ stration that it was also toxic to ferrets2, to cats3, and to rabbits4. It thus became a matter of some importance to discover the nature of the toxic factor and to assess the possible danger which might arise from the use of agenized flour. Method of Test Throughout the present investigation the criterion of toxicity adopted has been the production of a typical epileptiform fit in the ferret. The ferret is slightly less sensitive than the dog on a body-weight basis; but the small size of the animal enabled us to obtain a toxic reaction with a much smaller dose of agenized flour than would be necessary for a dog. The demonstration by Mellanby2 that toxicity was confined to the gluten fraction of the flour suggested that the toxic factor might be a modified amino-acid or peptide. The final method of isolation which is outlined below was based on this assumption. isolation of Crystalline Toxic Factor Flour was agenized by the standard procedure but with ten times the amount of nitrogen trichloride used in commercial practice (11T gm. NC13 to 17-7 kgm. flour). This flour was toxic to a ferret in