Phytochemicals and antioxidant activity of anacardium occidentale L.

Abstract

Anacardium occidentale, locally known as “pokok gajus” is known for its medicinal purposes. The objectives of this study are to isolate compounds from the stem bark extract of A. occidentale and to study the antioxidant properties of the extracts. Cold maceration method was performed for the extraction of A. occidentale stem bark. Purification of the crude extracts using column chromatography successfully isolated two compounds. The isolated compounds were elucidated using spectroscopic methods including Fourier Transform Infrared and Nuclear Magnetic Resonance spectroscopy. These compounds were identified as stearic acid and β- sitosterol. The antioxidant potential of the crude extracts was determined using a 2,2-diphenyl- 1-picrylhydrazyl (DPPH) radical scavenging assay. The results revealed that methanol extract was most effective in the capability to scavenge free radicals as it exhibited the highest radical scavenging activity towards DPPH with an IC50 value of 87.67 μg/mL. Total phenolic content and total flavonoid content of the extracts were measured. Both total phenolic and flavonoid contents showed a good correlation with the antioxidant activity indicated that both compounds were the major contributors to the antioxidant capacity of the extracts. Based on the findings, A. occidentale can be considered as an effective source of natural antioxidants.