Purification and Identification of Antioxidant Substances in Human-Placenta Extracts

Abstract

We attempted to purify and identify the active antioxidants in human-placenta extracts (PLx). Purification was performed successively by 40% methanol precipitation, Sephadex G-50 gel chromatography, and high-performance liquid chromatography (HPLC). The supernatant of PLx after 40% methanol precipitation possessed 85% of the original antioxidant activity. Elution of the antioxidants from gel chromatography gave mainly three peaks with approximately 98% recovery of the antioxidant activity. The antioxidant activity was then fractionated by HPLC with a recovery of approximately 90% of the activity. Three components were obtained, and based on HPLC retention times, UV, NMR, and FAB-MASS, they were identified as uracil, tyrosine, and phenylalanine.