Chromatographic Separation of Vitamin B6 Components in Food Extracts

Vitamin Value Assay, Comparison of Vitamin B6 Values of Selected Food Samples by Bioassay and Microbiological Assay

“…Analyses for proximate composition were made according to procedures of the AO AC (7) with minor modifications. Moisture determinations were made using the vacuum oven at 50°C.…”

“…Generally, reported losses of thiamine were slight (7,8) and nonsignificant (5, 6, 13) in red meats and poultry important nutritionally.…”

“…Results of tests for the stability of riboflavin were less consistent. Reported changes ranged from a decrease of 31% (7) to an increase of 22 to 42% (13) in pork loins, and decreases up to 46% were reported for beef rib steaks (5). Kotschevar (4) obtained greater losses of thiamine and riboflavin in sliced calf liver than in ground calf liver stored in an atmosphere of carbon dioxide, suggesting that oxidation during freezer storage could be a factor in losses of these two vitamins.…”

“…The chromatographic separation of food extracts into pyridoxine, pyridoxal, and pyridoxamine fractions, using an ion exchange column with Dowex 50 resin, has made it possible to assay for these three factors individually and to calculate the total vitamin B6 content of the food (3,6,7).…”

Vitamin B6 content of feeds

“…It was of interest to examine the pyridoxamine, pyridoxal, and pyridoxine contents of the few feedstuffs for which data are available to see whether this might be related to the type of extraction required for maximum liberation of vitamin Be. A number of studies (Polansky et al, 1964;Ra'oinowitz and Snell, 1948;Toepfer et al, 1960Toepfer et al, , 1963 have revealed wide variations in the relative amounts of the three forms of vitamin B6 from one material to another. There is some indication that 0.0557V acid extraction is more effective where pyridoxamine is predominant (Brewers' dried yeast and fish meal) or where pyridoxal is the major component (meat and bone meal).…”