Antifeeding activity of isoquinoline alkaloids identified in Coptis japonica roots against Hyphantria cunea (Lepidoptera: Arctiidae) and Agelastica coerulea (Coleoptera: Galerucinae).
The anti-feeding activity of 3 isoquinoline alkaloids identified from roots of Coptis japonica Makino toward 4th-instar larvae of Hyphantria cunea Drury and adults of Agelastica coerulea Baly was examined using the leaf-dipping bioassay. The biologically active constituents of the Coptis roots were characterized as the isoquinoline alkaloids berberine, palmatine and coptisine by spectroscopic analysis. In a test with H. cunea larvae, the anti-feeding activity was much more pronounced in an application of a mixture of palmatine iodide and berberine chloride (1:1, wt:wt) at 250 ppm (82.3%) and 500 ppm (100%), compared with palmatine iodide (76.0%) and berberine chloride (75.4%) alone at 500 ppm. These results indicate a synergistic effect. With A. courulea adults, berberine chloride showed 57.5 and 91.1% anti-feeding activity at 125 and 250 ppm, respectively; whereas, weak activity was obtained in application of 500 ppm of palmatine iodide (41.4%) and coptisine chloride (52.4%) alone. The Coptis root-derived compounds merit further study as potential insect-control agents.
Park
I K
IK
School of Applied Biology & Chemistry and Research Center for New Bio-Materials in Agriculture, College of Agriculture and Life Sciences, Seoul National University, Republic of Korea.
Lee
H S
HS
Lee
S G
SG
Park
J D
JD
Ahn
Y J
YJ
D000818:Animals; D001599:Berberine / Q000031:analogs & derivatives* / Q000737:chemistry; D001600:Berberine Alkaloids / Q000737:chemistry; D001517:Coleoptera; D005247:Feeding Behavior; D007546:Isoquinolines / Q000737:chemistry; D015394:Molecular Structure; D009036:Moths; D018517:Plant Roots; D010946:Plants, Medicinal
D001600:Berberine Alkaloids; D007546:Isoquinolines; C034384:coptisine; D001599:Berberine; C005413:palmatine