Inappropriate of In vitro antimicrobial and anticancer activities from cashew (Anacardium occidentale L.) nut shell extracts

Abstract

Objective: Cashew nut is one of the major agriculture products in Southern of Thailand, and the volume of cashew nut shell is become increase as a by-product. Thus, cashew nut shell is attractive source for evaluation of antimicrobial activities as inexpensive source. This study was aimed to evaluates in vitro antimicrobial properties of the water extract (CW) and ethanol extract (CE) from cashew nut shell and to evaluate anticancer activity and cytotoxicity of extracts by in vitro screening test against cell lines and normal mammalian cells, respectively. Materials and Methods: CW and CE extracts were determined total phenolic compound by Folin-Ciocalteu reagent. Antibacterial activity of CW and CE against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii were evaluated by resazurin microplate assay (REMA). Antimicrobial activities of both extracts against herpes simplex virus Type I and Mycobacterium tuberculosis were tested according by green fluorescent protein (GFP)-based assay; Candida albicans was tested according by REMA; and Plasmodium falciparum was tested according by microculture radioisotope techniques. Anticancer activities of CW and CE were tested with MCF7, NCI-H187, HepG2-, and Caco2 cell lines; and cytotoxicity test was used Vero and human dermal fibroblasts, neonatal (HDFn) cells. Results: CW and CE were lack of in vitro antibacterial (maximum concentration = 100 μg/ml), antimicrobial, and anticancer activities (maximum concentration = 50 μg/ml). CW and CE (0-50 μg/ml) were lack of cytotoxicity against Vero cells and HDFn-neonatal dermal fibroblast. Conclusions: CW and CE extracts of cashew nut shell had no significant in vitro anticancer and antimicrobial activities with noncytotoxicity.