Purification, identification and quantification of an egg‐weight‐depressing factor (vicine) in fababeans (<i>Vicia faba</i> L.)

Abstract

Abstract An egg‐weight‐depressing factor in fababeans was isolated in pure form from a white precipitate which had been shown in a previous study, to contain a concentrated form of this factor. The analytically pure compound was obtained in colourless, needle crystals. Its melting point was 242‐244°C, it contained 17.4% nitrogen but did not react with ninhydrin. The spectra had adsorption maxima at 274, 276 and 269 nm in acidic, neutral, and alkaline solutions, respectively. These and other properties were identical to those of vicine [2,6‐diamino‐4,5‐dihydroxy pyrimidine,5‐(β‐D‐glucopyrano‐side)] a compound known to be present in fababeans. Vicine and convicine [2,4,5‐trihydroxy, 6‐aminopyrimidine,5‐(β‐D‐glucopyranoside)]; compounds having similar chemical and probably physiological activity, were resolved on a cation‐exchange column and were detected by monitoring at 280 nm. Quantitative results obtained with the procedure was shown to be similar to those obtained with two other procedures. This method, however, was superior to other methods as it gave individual values for both vicine and convicine rather than a composite value; sample preparation was simple and the method could readily be adapted to automatic analysis.