Total polyphenol content, in vitro antifungal and antioxidant activities of callus cultures from inula crithmoides

Abstract

This is the first report on the antioxidant and antifungal activities of callus cultures from Inula crithmoides L. (Asteraceae). Callus cultures were initiated from leaf sections, on initial culture MS basal medium supplemented with various concentrations of 2,4-D (2,4-dichlorophenoxyacetic acid), NAA (1-naphthaleneacetic acid) and IBA (indole-3-butyric acid) and a 72% survival was achieved. Significant differences between the various auxins used as phytohormones on callus growth were found. Maximum callusing was noticed on the leaf explants grown on MS basal medium supplemented with 1 mgL-1 2,4-D. Subsequently the antioxidant and antimicrobial activities of the methanol extract from calli were investigated. Antioxidant studies suggested that the methanol extracts of dark-grown and light-grown callus were able to reduce the stable free radical 2,2-diphenyl-1-picrilhydrazyl (DPPH). In the inhibition against lipid peroxidation, extracts of dark-grown callus showed the strongest effect with IC50 values better than those of the standards. The methanol extract of callus cultures had significant antifungal activity only against two of the fungi tested: Alternaria solani and Phytophthora cryptogea. Against all the other tested fungi, the I. crithmoides calli extracts showed fungistatic activity.