Antioxidant activity in the extracts of two edible aroids

Abstract

Two neglected species of Araceae, Alocasia macrorhiza (Linn.) G. Don and Alocasia fornicata (Roxb.) Schott are important as food and ethno medicine in Asia and Africa. Their bioefficacy is documented in the Ayurveda. The solvent extracts of different edible parts of these two species like rhizomes, leaves, roots and stolons were screened for in vitro antioxidant properties using standard procedures. The successive extracts in hexane, benzene, toluene, chloroform, diethyl ether, ethyl acetate and water fraction exhibited IC(50) values in the following order, roots>rhizome>leaves for Alocasia macrorhiza and leaves>stolon for Alocasia fornicate, respectively in 2,2-diphenyl-1-picryl hydrazyl antioxidant inhibition assay. Maximum antioxidant activity was observed in diethyl ether extracts for both species. The IC(50) values were comparable with those of quercetine and ascorbic acid as standards. These results suggest that the two aroid species have antioxidant activity in their edible parts and should be extracted using diethyl ether solvent.

Keywords: Alocasia fornicata (Roxb.) Schott; Alocasia macrorhiza (Linn.) G. Don; Antioxidants; Edible aroids; Extraction; free radical scavenging.

Fig. 1

Giant taro, Alocasia macrorhiza (linn.) G. Don

Fig. 2

Shola kachu, Aalocasia fornicata (roxb.) Schott

Fig. 3

Calcium oxalate crystals in roots of giant taro Alocasia macrorhiza (linn.) G. Don