Antimicrobial Evaluation of Cardol and Cardol-Metal Complexes from the Nut Shell Liquid of <I>Anacardium occidentale</I>


  • David G. Oke Industrial Chemistry Programme, College of Agriculture, Engineering and Science, Bowen University, Iwo, Osun State, Nigeria.
  • Adesoji A. Olanrewaju Industrial Chemistry Programme, College of Agriculture, Engineering and Science, Bowen University, Iwo, Osun State, Nigeria.
  • Esther O. Faboro Industrial Chemistry Programme, College of Agriculture, Engineering and Science, Bowen University, Iwo, Osun State, Nigeria.
  • Labunmi Lajide Chemistry Department, Faculty of Science, Federal University of Technology Akure, Nigeria.


Cardol, as one of the major constituents of Cashew Nut Shell Liquids has received little attention
in terms of modification and applications. The presence of two hydroxyl groups and an alkyl side
chain of 15 carbon length make it a natural compound of interest. The present study is aimed at
modification and complexation of cardol, and the antimicrobial investigations of the compound
as well as its analogue and complexes. Isolated cardol from cashew nut shell liquid was nitrated,
and the compounds were used in the synthesis of metal (II) complexes of Copper, Cobalt, and
Zinc. The compounds and complexes were characterised by melting points, UV-Vis
spectrophotometry, Fourier Transform Infrared (FTIR) spectrophotometry, and Nuclear Magnetic
resonance (NMR) spectroscopy. The antibacterial and antifungal evaluations of both the
compounds and complexes were tested in vitro against some selected bacteria and fungi. From the
results, Copper complex of nitrocardol produced significantly higher antibacterial zone of
inhibition (11.5 ± 2.1 mm) against Pedobacter mendelii than tetracycline while Copper complex
of cardol showed significantly higher antifungal activity (13.5 ± 2.1 mm) against Rhizopus
stolonifar than clotrimazole (10.0 ± 0.0 mm). It was generally observed that modification and
metal complexation enhanced the antimicrobial activity of cardol. Further studies on these
complexes could be done to enhance their potencies and potentials for use as antibacterial and
antifungal agents.
Keywords: Anacardium occidentale, Cardol, Antifungal, Antibacterial, Complex


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How to Cite

Oke, D. G., Olanrewaju, A. A., Faboro, E. O., & Lajide, L. (2023). Antimicrobial Evaluation of Cardol and Cardol-Metal Complexes from the Nut Shell Liquid of <I>Anacardium occidentale</I>: Tropical Journal of Natural Product Research (TJNPR), 7(7), 3532–3537. Retrieved from