Abstract

BIOACTIVITY AND COMPOSITION OF THE FLOWERS OF SPATHODEA CAMPANULATA P. BEAUV

Naglaa G. Shehab, Hanaa H. Eid and Soheir M. El Zalabani

Abstract

Among plant metabolites, phenolics were found to possess a wide spectrum of biological activities. The purpose of this study was to investigate the ethanol extract of the flowers of Spathodea campanulata P. Beauv. (EEFSC) in terms of bioactivity and composition. Special emphasis was made on its phenolic components. The LD50 of EEFSC (up to 4 g/kg) indicated its safety. The growth inhibitory activity of EEFSC, and its hexane, chloroform, ethyl acetate and n-butanol fractions was evaluated in-vitro against a set of microorganisms and 2 human tumor cell lines (breast and colon). The chloroform fraction exhibited the highest antibacterial effect and the least IC50 against both cell lines. The anthelmintic and acute anti-hyperglycemic potentialities of EEFSC were also explored and found noticeably significant. RP-HPLC with UV detection was employed for identification and quantification of the floral phenolics. Six compounds were isolated from the active chloroform and ethyl acetate/n-butanol fractions. The purified isolates included three phenolics, and were identified as phytol, α- methylcinnamaldehyde, β-sitosterol-3-acetate, naringenin, catechin-3-O-α-rhamnopyranoside and 5, 6, 4' trihydroxy flavonol-7-O-α-rhamnopyranoside, all being for the first time reported from the flowers. The observed bioactivities were correlated to the isolated constituents.

Keywords: Spathodea campanulata, Flowers, Antitumor, Anthelmintic, Antihyperglycemic.