Investigation of the chemical composition, antimicrobial and antioxidant activities of cashew nut testa extracts (Anacardium occidentale L.)

Abstract

The cashew nut testa (Anacardium occidentale L.) is an agricultural byproduct with great potential, containing numerous natural compounds with significant biological activities. This study investigates the chemical composition, antimicrobial properties, and antioxidant capacity of the ethyl acetate extract derived from cashew nut testa. Qualitative analysis revealed the presence of compounds such as polyphenols, flavonoids, coumarins, and tannins, while alkaloids and saponins were not detected. The total polyphenol and catechin contents, along with their derivatives, were 566.50±0.76 mg GAE/g and 517.50 mg/g, respectively, with catechin (247.21 mg/g) being the predominant compound, followed by epigallocatechin gallate (166.27 mg/g) and epicatechin (94.49 mg/g). The extract exhibited strong antimicrobial activity, particularly against Staphylococcus aureus (21.00±0.50 mm) and Candida albicans (11.33±0.58 mm). Furthermore, the extract demonstrated remarkable antioxidant activity, with an IC50 value of 10.05±0.06 µg/ml, which was lower than that of vitamin C (11.62±0.18 µg/ml). These findings suggest that the ethyl acetate extract from cashew nut testa is a promising raw material with potential applications in pharmaceuticals and functional foods.