A nematicidal tannin from Punica granatum L. rind and its physiological effect on pine wood nematode (Bursaphelenchus xylophilus).

Abstract The ethanol extract of Punica granatum L. rind was tested to show significant nematicidal activity against pine wood nematode. Three nematicidal compounds were obtained from the ethanol extract by bioassay-guided fractionation and identified as punicalagin 1 , punicalin 2 , and corilagin 3 by mass and nuclear magnetic resonance spectral data analysis. Punicalagin 1 was most active against PWN among the purified compounds with the LC 50 value of 307.08 μM in 72 h. According to the enzyme assays in vitro , punicalagin 1 could inhibit the activity of acetylcholinesterase, amylase and cellulase from PWN with IC 50 value of 0.60 mM, 0.96 mM and 1.24 mM, respectively. The morphological structures of PWNs treated by punicalagin 1 were greatly changed. These physiological effects of punicalagin 1 on PWN may helpful to elucidate its nematicidal mechanism.