Researchers from Nigeria investigated the bioactive constituents of Anacardium occidentale, also known as cashew, and evaluated its effects on histamine-induced paw edema and bronchoconstriction. They reported their findings in an article published in the Journal of Integrative Medicine.
The leaves of A. occidentale have long been used for the treatment of inflammation and asthma, but the bioactive components responsible for these activities have not been characterized.
For their experiment, the researchers prepared extracts from the leaves of A. occidentale using ethanol as solvent.
They used gas chromatography and mass spectrometry to identify the active components of the extracts and their solvent-soluble portions.
Isolation and characterization of these components were done using column chromatography and Fourier transform infrared spectroscopy, respectively.
The researchers then measured the percentage of protection provided by the extracts using guinea pigs with histamine-induced bronchoconstriction.
They examined their anti-inflammatory effect by measuring the increase in paw diameter and calculating the percent edema inhibition in rats with histamine-induced paw edema.
The researchers reported that the A. occidentale extracts and their hexane-, ethyl acetate- and chloroform-soluble portions exhibited significant bronchodilatory and anti-inflammatory activities.
They identified oleamide (9-octadecenamide) as the most abundant compound in the A. occidentale extracts.
Compared with the extracts and their solvent-soluble portions, oleamide showed higher bronchodilatory (32.97 percent) and anti-inflammatory activities (98.41 percent).
Based on these findings, the researchers concluded that A. occidentale leaf can be used for the management of bronchoconstriction and inflammation, thanks to the bronchodilatory and anti-inflammatory activities of its active component, oleamide.
Journal Reference:
Awakan OJ, Malomo SO, Adejare AA, Igunnu A, Atolani O, Adebayo AH, Owoyele BV. ANTI-INFLAMMATORY AND BRONCHODILATORY CONSTITUENTS OF LEAF EXTRACTS OF ANACARDIUM OCCIDENTALE L. IN ANIMAL MODELS. Journal of Integrative Medicine. January 2018;16(1):62–70. DOI: 10.1016/j.joim.2017.12.009