The Isolation of Cotton Plant Components by High-Performance Liquid Chromatography

Abstract

The use of high-performance liquid chromatography (HPLC) to separate components of extracts of cotton bracts is described. A chloroform extract of the aqueous extract of the bracts and an ethanol extract of the dried aqueous extracts were used. The facile separation of 1,7-dihydroxy-4-isopropyl-1,6-dimethyl-2(1H)-naphthalenone (lacinilene C), its 7 methyl ether, and β-sitosterol from the chloroform extract, and 7-hydroxy-6-methoxycoumarin (scopoletin), cinnamic acid, and hydroxy cinnamic acid from the ethanol extract illustrate the capability of HPLC to separate the complex mixture of compounds in cotton plant parts. Preliminary separations by preparative thin-layer chromatography gave several major bands, but the HPL chromatograms showed that each band contains the same compounds, though in varying concentration, demonstrating the higher resolution of HPLC. Scopoletin was a major component in both extracts. Cinnamic and hydroxy cinnamic acids were identified by GC/MS. The other compounds were identified by pmr spectroscopy.