Naturally occurring odd number fatty acids in the rhizome oil of Alpinia speciosa K. Schum.

Abstract

Contrary to usual observations, the rhizome oil of Alpinia speciosa K. Schum. is found to contain not only one but as much as five odd number carbon atoms containing natural fatty acids, apart from eight even carbon fatty acids. Among the fatty acids containing odd number of carbon atoms, the useful pentadecanoic acid (C-15) is main (21.9%) and others are C-23 (5.7%), C-13 (1.9%), C-11 (3.1%) and C-9 (0.1%). Among the fatty acids containing even number of carbon atoms, the highly unsaturated linolenic acid (C-18:3) is main (27.4%) and the next is the very useful arachidic acid (C-20), 22.4%. The total saturated fatty acids constitute 65.7% and unsaturated 34.3%.