Antioxidant and Cytotoxic Phenolic Compounds of Areca Nut(Areca catechu)

Areca catechu L.(Palmae), commonly known as an important economical seed crop, is widely cultivated in tropical and subtropical areas, including India, Southeast Asia, East Africa and New Guinea. Areca nut(frequently known as betel nut) is the ripe fruit of the tree A. catechu. Areca nut can be chewed and it is a common masticatory in tropical and subtropical countries. It was estimated in the early 1990s that 10% to 20% of the world’s population chewed betel quid daily. Areca nut is commonly used in folklore medicine for treatment of various diseases such as dyspepsia, constipation, beriberi and oedema. It’s reported that the areca nut of A. catechu possesses anthelmintic, anti-inflammatory, antioxidant, psychoactive, antidepressant, anti-HIV-1 effects and so on. Areca nut contains 50%―60% sugars, 15% lipids (glyceride of lauric, myristic and oleic acid), 15% condensed tannins(phlobatannin, catechin), polyphenolics(NPF-86IA, NPF-86IB, NPF-86IIA and NPF86IIB) and 0.2%―0.3% alkaloids(arecoline, arecaidine, guvacine and guvacoline). Although a lot of literature showed that areca nut had a strong antioxidant activity, no exact component contributing the antioxidant activity to areca nut has been reported yet. During the course of our searching for antioxidant genus from tropical medicinal plants, 11 phenolic compounds possessing antioxidant activity were isolated by bioassay-guided fractionation from the EtOAc fraction of areca nut, which exhibited considerable antioxidant activity by DPPH assay in our preliminary test. This paper describes the structural determination of these compounds, their antioxidant activities by DPPH assay, and cytotoxic activity by MTT method.