Classification of some Boesenbergia and Alpinia extracts and their medicinal products based on chemical composition, antioxidant activity, and concentration of some heavy metals

Abstract

The result showed total phenolic content, total flavonoid content and radical scavenging activity in ethanol extracts higher than oil extracts and massage products of Boesenbergia rotunda, Alpinia conchigera, Alpinia galangal, and Alpinia siamensis. Fourier-transform infrared spectroscopy of the ethanol extracts provided specific peaks in a range of 4,000 to 550 cm1 . Chemical differentiation between Alpinia sp. and Boesenbergia sp. was indicated by main peaks that corresponded to aromatic and N-H in amino acids, O-H in phenyl group, and C-O in carbohydrates and glycoprotein. Chemical differentiation among three Alpinia species were wavenumber ranges of C-O in acid or ester, C-O in carbohydrates and glycoprotein, and C-H in isoprenoids. The cluster and PCA analysis showed good separation of chemical compositions and antioxidant activity among the ethanol extract, massage solution and oil extract. Additionally, Ni, and Cd were found in all massage products, especially Ni above its maximum permission level.