An efficient method for the quantification of hydroxamic acids from wheat by thin layer chromatography-densitometry

A new method is described for the quantification of 2,4-dihydroxy-7-methoxy -1,4-benzoxazin-3-one (DIMBOA) and 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBO A), the main hydroxamic acids in wheat and rye extracts, respectively, in c ereal extracts based on densitometry of scanned thin layer chromatographic plates. The method allows the simultaneous quantification of up to five sam ples, and is linear between 0.5-7 mu g and 10-30 mu g for DIMBOA and betwee n 0.5-3.0 mu g and 10-30 mu g for DIBOA. Quantification of DIMBOA by this m ethod generates a linear correlation with results obtained following analys is by high performance liquid chromatography. The possibility of applying t his methodology to mixtures of DIBOA and DIMBOA is discussed. (C) 1998 John Wiley & Sons, Ltd.