Assessment of zinc deficiency and effect of dietary carrot, amchur and onion on zinc status during repletion in zinc-deficient rats

BACKGROUND: Food acidulants, beta-carotene-rich vegetables and sulfur compound-rich Allium spices are known to improve zinc bioaccessibility from food grains. This animal study evaluated the positive influence of these promoters of zinc bioaccessibility on zinc status during zinc repletion in Wistar rats previously rendered zinc-deficient by feeding a zinc-deficient semi-synthetic diet for 4 weeks. Groups of these zinc-deficient animals were subsequently maintained on a zinc-containing grain-based diet for 2 weeks. Various experimental diets consisted of the grain-based diet supplemented with (1) carrot, (2) onion, (3) amchur, (4) carrot + amchur and (5) onion + amchur. RESULTS: Zinc deficiency was confirmed by lower zinc concentration in tissues and bones and lower activity of zinc-containing enzymes. Zinc concentration was 10-15% lower in serum, liver and kidney of zinc-deficient rats. Bone weight in zinc-deficient rats was 20% lower than that in normal rats. Activities of zinc-containing enzymes ( hepatic superoxide dismutase and alcohol dehydrogenase and serum alkaline phosphatase) were lower in the zinc-deficient group. Animals fed diets supplemented with these promoters of zinc bioaccessibility showed better zinc status in tissues and bones compared with those repleted with the control stock diet. CONCLUSION: This animal study supports the claim of promoters of zinc bioaccessibility for improving zinc status, which may find practical application. (C) 2011 Society of Chemical Industry