VITAMIN-B6 AND PYRIDOXINE GLUCOSIDE CONTENT OF WHEAT AND WHEAT FLOURS

Analysis of different wheats and flours for vitamin B6 using water ext racts and reverse-phase high-performance liquid chromatography reveale d significant variation in content of pyridoxine (PN) and pyridoxine g lucoside (PNG), a glycosidic adduct of B6 with partial human bioavaila bility found in many plant foods. Other vitameric forms of vitamin B6 were not detected. In 22 American and Canadian wheats, total vitamin B 6 (the sum of PN plus PNG observed in samples) content varied over a t hreefold range of 3.4 to 11.1 nmol/g. PNG accounted for a significant portion of the variation (1.9-8.8 nmol/g), with less variation in PN ( 0.9-2.7 nmol/g). Mean values (+/- standard deviations) were 5.0 +/- 1. 8 nmol/g for total vitamin B6; 1.7 +/- 0.5 nmol/g for PN; and 3.4 +/- 1.8 nmol/g for PNG. American hard wheats contained significantly more vitamin B6, mostly as PNG, compared to Canadian hard wheats. The same pattern was seen for Colorado hard wheats compared to others. Hard whe ats contained more vitamin B6 than did soft wheats. Flours milled from 16 of the cultivars contained approximate to 75 less B6 than did the corresponding wheats.