Removing Pb2+ with a pectin-rich fiber from sisal waste.

A pectin-rich dietary fiber from sisal waste (P-SF), containing 11.8% pectin, was produced by a sequential enzymatic-ultrasonic process. P-SF was effective in adsorbing Pb2+ from aqueous solution with a maximum adsorption amount of 184 mg g−1. Adsorption isotherms were fitted well by the Langmuir equation, and the adsorption kinetics could be described by a pseudo-second-order model. X-ray photoelectron spectroscopy and energy dispersive spectroscopy suggested that Pb2+ was adsorbed by P-SF via ion exchange, complexation and mineral precipitation. Dietary supplementation with 10% (w/w) P-SF in basal feed led to a significant decrease in Pb2+ in the brain, liver and kidney. P-SF has greater in vivo efficacy of Pb2+ removal as compared to commercial soybean dietary fiber. The reduction of brain Pb2+ level by P-SF was as effective as by a Pb2+ excretion drug. These findings suggested that P-SF has a great potential to be used as a dietary supplement to cope with Pb2+ poisoning.