GC-MS profile and cytotoxicity of the hydrodistilled and extracted volatiles of the buds and flowers of Spathodea campanulata P. Beauv.

Abstract

Volatiles of Spathodea campanulata buds and expanded flowers were isolated by hydrodistillation / solvent extraction and direct solvent extraction. Products analysed included: primary and recovered oils (PO/RO) derived from distillates, chloroform extractives (CE) of the non-distilled fractions, and hexane concretes (HC). Number of components identified by GC-MS varied from 35-60 (88.56 - 98.17 % of the total composition). PO/RO showed close amounts of hydrocarbons and oxygenated compounds; yet, the latter prevailed in CE and HC samples. Hydrocarbon fraction was the least in buds CE (15.36 %) and greatest in flowers PO/RO (48.04 %); meanwhile, oxygenated constituents dominated flowers HC (74.04 %). Chief hydrocarbons were: alkanes and alkenes (flowers CE, 32.46 %; major phytane 16.41 %), and terpenoids (PO/RO: buds 22.44 %, major α-pinene 9.34 % vs. flowers 19.91 %, major β-selinene 8.51 %). Oxygenated constituents included: carbonyl compounds (flowers CE 31.83 %; major 6-benzofurancarboxyaldehyde 27.75 %); acids (HC: flowers 52.16 %, major hexadecanoic acid 32.47 % vs. buds 51.64 %, major 9, 12-octadecadienoic acid 30.19 %); esters and lactones (buds CE, 66.24 %; major 1, 2-benzenedicarboxylic acid diisooctyl ester, 38.99 %; and PO/RO, buds 31.52 % vs. flowers 28.01 %). The volatiles exhibited variable cytotoxic activities against (MCF7) and (HCT116) cell lines. Buds HC demonstrated the lowest IC50 (4.2 µg/ml). In conclusion, the stage of development and isolation techniques obviously influenced yield, composition and bioactivity.