Chemical characterization and antioxidant activities of polysaccharides isolated from the stems of Parthenocissus tricuspidata.

Four polysaccharides, PTP-1, PTP-2, PTP-3 and PTP-4, were obtained from the water extraction of the stems of P. tricuspidata by anion exchange chromatography and gel filtration. The antioxidant activities of four PTPs were investigated, exhibiting different antioxidant activities, in which PTP-4 performed noticeable, with strong superoxide radical activity (comparable to BHT), high DPPH radical activity (78.53% at 1250 μg/mL), moderate hydroxyl radical scavenging activity and reducing power activity. Furthermore, the chemical structure of PTP-4 was measured by FT-IR, GC, 1H and 13C NMR spectra, indicating its mainly composition of the arabinose, xylose, galactose, glucuronic acid, and mannose. Thus, the stems of P. tricuspidata could be used as a potential source for natural antioxidant.