C22:1 omega 5-anacardic acid was found to be a good inhibitor of both potato lipoxygenase and ovine prostaglandin endoperoxide synthase with approximate IC50's of 6 and 27 microM, respectively. Very similar inhibition was seen with the crude exudate, rich in omega 5-anacardic acids, from glandular trichomes of an arthropod-resistant strain of geranium, Pelargonium xhortorum. The saturated anacardic acid (C22:0 sat), abundant in the trichome exudate of susceptible strains, was nearly as inhibitory toward both prostaglandin endoperoxide synthase and lipoxygenase as the omega 5-unsaturated compound. However, the dimethyl derivative of C22:1 omega 5-anacardic acid was a poor inhibitor of prostaglandin endoperoxide synthase and caused only moderate (32%) inhibition of lipoxygenase even at 135 microM. The possible role of prostaglandin endoperoxide synthase and lipoxygenase inhibition in the enhanced pest resistance of geraniums which produce the omega 5-AnAs is discussed.
Inhibition of lipoxygenase and prostaglandin endoperoxide synthase by anacardic acids
Grazzini, R., Hesk, D., Heininger, E., Hildenbrandt, G., Reddy, C. C., Cox-Foster, D., Medford, J., Craig, R., & Mumma, R. O. (1991). Inhibition of lipoxygenase and prostaglandin endoperoxide synthase by anacardic acids. Biochemical and Biophysical Research Communications, 176(2), 775-780.