Leigh M J, Miller D D
Am J Clin Nutr. 1983 Aug;38(2):202-13. doi: 10.1093/ajcn/38.2.202.
Iron binding by isolated dietary fiber in the presence of iron ligands was measured. Iron-ligand solutions were mixed with isolated fiber and incubated. Bound and polymerized iron were estimated by centrifugation and ultrafiltration, respectively. Results showed that iron binding varied greatly with ligand used and with pH. Based on these studies, it was predicted that ligands would influence iron availability in the order ascorbate less than citrate = nitrolotriacetic acid less than EDTA. When added to a complex meal containing beef, bread, green beans, and milk, iron availability (measured by an in vitro method) was little affected by fiber, citrate, and ascorbate, but enhanced by nitrolotriacetic acid and EDTA. When added to a semisynthetic meal, fiber, ascorbate, citrate, nitrolotriacetic acid, and EDTA increased iron availability. It appears that the effect of dietary fiber on iron availability is greatly dependent on the ligands present in the meal.
测定了在铁配体存在下分离出的膳食纤维对铁的结合情况。将铁 - 配体溶液与分离出的纤维混合并进行孵育。分别通过离心和超滤来估算结合态铁和聚合态铁。结果表明，铁的结合情况会因所用配体以及pH值的不同而有很大差异。基于这些研究，预计配体对铁有效性的影响顺序为抗坏血酸小于柠檬酸盐 = 次氮基三乙酸小于乙二胺四乙酸。当添加到含有牛肉、面包、青豆和牛奶的复合餐中时，铁的有效性（通过体外方法测定）受纤维、柠檬酸盐和抗坏血酸的影响较小，但次氮基三乙酸和乙二胺四乙酸会提高其有效性。当添加到半合成餐中时，纤维、抗坏血酸、柠檬酸盐、次氮基三乙酸和乙二胺四乙酸会提高铁的有效性。看来膳食纤维对铁有效性的影响在很大程度上取决于餐食中存在的配体。
