Antioxidant Activity of Aqueous Extract Fractions of Velvet Antler (Cervus elaphus Linnaeus)

Velvet antler is believed to have body strengthening, immunomodulatory and anti-aging effects. It is used in Chinese commercial functional foods and nutraceuticals. The antioxidant activity of the aqueous extract of velvet antler (AEVA) from Germs elaphus Linnaeus was evaluated with DPPH-radical scavenging, FRAP, Fe(2+) -chelating and inhibition of linoleic acid autoxidation assays. AEVA showed antioxidant activity in all four assays. After removal of protein from AEVA, the antioxidant activity was significantly elevated. A semi-preparative HPLC equipped with a C(18) column was used for further separation of the non-protein components (AEVA-S). Identification of the most active fraction (AEVA-SII) of AEVA-S was accomplished by LC/MS, HPLC and UV/Vis analyses. The HPLC chromatogram showed five main peaks identified as nucleotides (3'-CMP, 2'-CMP, 3'-UMP and 2'-UMP) and hypoxanthine. Nucleotides in AEVA-SII exhibited no free-radical scavenging and ferric-reducing activity. Only UMP exhibited Fe(2+)-chelating activity which accounted for 34.75% of the total Fe(2+) -chelating activity of AEVA-SII. The results indicated that other unidentified components with antioxidant activity were present in AEVA-SII.