Low esterified pectin accelerates removal of lead ions in rats

Dietary pectin is an essential part of human diet possessing numerous beneficial properties including its capacity to bind metal ions, in particular, those of lead. It was suggested that pectins with different structure may variously influence lead metabolism and its toxicity. The present study was conducted to estimate metal binding capacity of calcium pectate and pectins with low and high degree of esterification and their effects on lead absorption, retention, and removal in laboratory rats. Under in vitro conditions, low esterified pectin was the most effective and bound 2.2 mmol of lead per gram. Treatment of rats with low esterified pectin and calcium pectate significantly reduced lead retention in liver, heart, kidney, and bones. In rats preliminary given the lead solution, removal of the metal ions from organs and femur after administration of low esterified pectin or calcium pectate was more pronounced than after treatment with high esterified pectin. This was proven by the several times reduced lead concentration in organs and 45.7% and 21% increased metal content in feces of the animals, respectively, for calcium pectate and low esterified pectin. The results suggest that pectin with a low degree of esterification and calcium pectate may be considered as perspective dietary compounds removing environmental lead from the body.