Planta Med 2009; 75 - PA60
DOI: 10.1055/s-0029-1234385

Isolation and structure elucidation of new antioxidants from leaves of Populus ussuriensis

CL Si 1, 2, L Wu 1, ZY Zhu 1, SM Li 3
  • 1Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science and Technology, 300457 Tianjin, China
  • 2State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, 510640 Guangzhou, China
  • 3Institut für Pharmazeutische Biologie, Philipps-Universität Marburg, D-35032 Marburg, Germany

Populus ussuriensis Kom. (Salicaceae) leaves have been widely used in folk medicines to treat various diseases [1–2]. A 70% acetone extract of P. ussuriensis leaves was analyzed for antioxidant activity by ABTS ·+ and DPPH free radical scavenging assays. After partitioning with several solvents, the EtOAc soluble fraction, which showed strong antioxidant activity, was further purified by Sephadex LH-20 column chromatography. The known phenolic acids ρ-coumaric acid (I) and caffeic acid (II), 5 known phenolic glucosides, salireposide (III), populoside (IV), suwonpopuloside (V), salicortin (VI) and grandidentatin (VII), and 2 new phenolic glucosides, 2-hydroxycyclohexyl-4'-O-p-coumaroyl-β-D-glucopyranoside (VIII) and 2-hydroxycyclohexyl-6'-O-p-coumaroyl-β-D-glucopyranoside (IX) were isolated as the active principles and their structures were elucidated on the basis of physicochemical and spectroscopic methods. This is the first report of the chemical composition of P. ussuriensis. Compounds I-VI and IX showed significant antioxidant activities (DPPH IC50 values of 6.68, 6.61, 6.75, 6.84, 6.76, 6.79 and 5.92 µM, respectively; ABTS ·+ TEAC values of 1.21, 1.28, 1.26, 1.05, 1.69, 1.60, and 2.00 mM, respectively), suggesting they may be exploited as biopreservatives in food applications and health supplements in functional food, to alleviate oxidative stress.

R1=p-coumaroyl, R2=H (VIII); R2=p-coumaroyl, R1=H (IX) (p-coumaroyl)

Acknowledgement s: Financial support from Natural Science Foundation of Tianjin City (09JCYBJC15800, 09JCZDJC21800).

References: [1] Zhang, XF. et al. (2006)J. Nat. Prod. 69:1370-1373.

[2] Lin, M. et al. (1993) Acta Pharm. Sinic. 28:437-441.