ABSTRACT
The bran of black rice contains 210～480 ppm iron, 50～70ppm zinc and 14.1% protein. In order to evaluate the bioavailability of bran iron, its relative biological availability (RBA) has been studied by means of the hemoglobin regeneration technique in anemic rats. All the rats were divided into five groups, the low-iron basal diet was supplemented with 23ppm Fe of ferrous sulfate in group A, 11.5% bran in group B, 11.5% bran plus 0.2% Vc in group C, 11.5% bran plus 2.3% cooked lean pork in group D and nothing in group E as the negative control The efficiencies of converting iron from the diet of group A, B, C, D into hemoglobin were 59%, 33%, 33% and 39% respectively and the relative biological availabilities were 100%, 56%, 56% and 66% respectively.
ABSTRACT
In order to clarify the disputing view-points in some publications, that the soy products are whether unfavourable or not to the bioavailability of diet iron, we estimated the relative bioavailability of the iron from soy flour by hemoglobin regeneration method in rats suffered from iron deficiency anemia. In this experiment the ferrous sulfate was used as a standard, wheat flour as a vehicle, and the pig blood powder as a reference substance. The iron content in the regeneration diet fed to rats of each group was 32 ppm in total, and among it 24ppm was originated from (1) soy flour, (2) soy flour plus wheat flour (half and half), (3) pig blood powder, (4) pig blood powder plus wheat flour (half and half), and (5) ferrous sulfate respectively.The experimental results showed that during the 5-week regeneration period the regenerated hemoglobin level of the rats of corresponding groups were (1) 6.6?1.6→9.4?1.7, (2) 7.0?0.9→10.4 ?1.5, (3) 6.4?1.6→ 11.4?1.4, (4) 6.1?0.6-11.1?1.9, and (5) 5.3?1.2-12.8 1.0, thereby the percentage of iron relative bioavailability of five groups were (1)45.4, (2)65.0, (3)74.0, (4)72.0, (5)100.0 respectively. The iron from soy flour showed a lowest bioavailability aalong the different diet sources in our exper-iment, and therefore the iron from soy products was unfavourable to prevent and treat the iron deficiency anemia. We also made some discussions and suggestions in this paper.