The detection of metabolic products from dimethylnitrosamine in rats and mice

Abstract

CANAVANINE IN LEGUMINOSAE 619kept at 40 for 12 hr.The crystalline flavianate was filtered off, recrystallized five times from water and decomposed with Ba(OH),.The base was finally obtained in the form of its hydrated sulphate as previously described (Fearon & Bell, 1955).Yield 2*8 g., m.p. (after shrivelling at 1620) 170-171' (decomp.)not depressed when mixed with authentic canavanine sulphate (Found: C, 20-9; H, 5-5; N, 19-4; a-NH2 N, 5-3.Calc.for C5Hj203N4,H2S04,H20: C, 20-5; H, 5-5; N, 19-2; x-NH2 N, 4.8 %).[a] i?+ 18 i 20 in water (c, 10); canavanine sulphate monohydrate from Colutea arboremcen8 (Fearon & Bell, 1955) had [a]18 ' + 18-6.Finely ground seed (100 g.) of Medicago 8ativa was extracted as described for Anthyflis vulneraria.The two extracts were combined, concentrated to 200 ml.by distillation under reduced pressure and filtered before the addition of 5 vol. of ethanol.The amino acid was purified by recrystallizing its flavianate and finally isolated as the sulphate.Yield 1-5 g.; m.p. (after shrivelling at 1620) 1720 (decomp.)not depressed when mixed with authentic canavanine sulphate (Found: C, H, N, o-NH2 N, 4.5%).[`] + 18+20 in water (c, 2.2).SUMMARY 1. Methods are described for the identification of canavanine in biological extracts containing com- pounds which mask or inhibit the guanidoxy colour reaction given by canavanine with tri- sodium pentacyanoamnonioferrate.2. It has been shown that canavanine occurs in the seeds of sixteen legunminous plants; quantitative values for eight are given.The acid has been isolated from two of them.3. In addition to canavanine other compounds which, like the guanidoxines, react with trisodium pentacyanoammonioferrate at pH 7 have been detected in the seeds of leguminous plants.