Altitudinal variation in the volatile constituents of Artemisia nilagirica

The essential oils of Artemisia nilagirica (Clarke) Pamp. of the family Asteraceae collected from different altitudes of the Garhwai region were subjected to detailed GC/MS analysis in order to determine the variation of concentration in their constituents. Plants collected from 500 m altitude afforded [alpha]-thujone (36.99%) as a major constituent whereas only a small percentage of [alpha]-thujone was found in the plants collected from two other sites.The 4-nitrobenzonoic acid-4-methoxyphenyl ester (22.12%) was obtained in a high concentration from the plants collected at 1200 m altitude but in the plants from two other altitudes it was found only in small proportion. Similarly, I-linalool (32.47%) was the major constituent of plants at 2000 m altitude but in other plants it was detected in very low concentration. Since the concentration of plant constituents changed from one altitude to another, the medicinal properties of such plants would vary accordingly. Key words: Artemisia nilagirica, Asteraceae, anti-dermatophytic activity, [alpha]-thujone, I-linalool