Planta Med 1991; 57(1): 65-68
DOI: 10.1055/s-2006-960021

© Georg Thieme Verlag Stuttgart · New York

Activity-Guided Isolation and Identification of Azadirachta indica Bark Extract Constituents which Specifically Inhibit Chemiluminescence Production by Activated Human Polymorphonuclear Leukocytes

J. M. van der Nat1 , W. G. van der Sluis1 , L. A. 'tHart1 , H. Van Dijk2 , K. T. D. de Silva3 , R. P. Labadie1
  • 1Section of Pharmacognosy, Faculty of Pharmacy, State University of Utrecht, Catharijnesingel 60, 3511 GH Utrecht, The Netherlands
  • 2Section of Experimental Immunology, Laboratory for Microbiology, Medical Faculty, State University of Utrecht, Utrecht, The Netherlands
  • 3Department of Chemistry, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
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Publication History


Publication Date:
05 January 2007 (online)


The A. indica crude aqueous bark extract inhibits the generation of chemiluminescence by activated human polymorphonuclear leukocytes (PMN). Guided by this activity the responsible compounds were purified by extraction with different organic solvents and HPLC. Gallic acid, (+)-gallocatechin, (-)-epicatechin, and (as a 2:1 mixture) (+)-catechin and epigallocatechin were isolated and identified by means of HPLC, TLC, MS, 1H-NMR, UV, and CD data. Commercial samples of gallic acid, (+)-catechin and (-)-epicatechin showed the same effects. To our knowledge the identified catechins have never been described as constituents of A indica.