Chemical Diversity of Essential Oil of from Different Altitudes of Himalaya and Distillation Methods.

is an important temperate herb that is used in the pharmaceutical and essential oil industries. In India, this species is now on the verge of extinction due to the over-exploitation of its rhizomes from its natural habitat. It is hypothesized that the variations in bioactive compounds in its essential oil are very high among the wild populations as well as cultivated sources. Thus, this study was conducted to evaluate the chemical profiling of essential oil of four wild populations (Rupena, Kugti, Garola, and Khani) and two cultivated sources (CSIR-IHBT, Salooni), which were distilled at three consecutive days. The variation in oil concentration in roots/rhizomes was found significant ( ≤ 0.05), and the maximum value (0.35%) was registered with the population collected from Kugti and Khani. In essential oil, irrespective of population and distillation day, patchouli alcohol was the major compound, which ranged from 19 to 63.1%. The maximum value (63.1%) was recorded with the essential oil obtained from Garola's population and distilled on the first day. The percentage of seychellene was abruptly increased with subsequent days of extraction in all the populations. The multivariate analysis revealed that the essential oil profiles of Rupena, Kugti, Garola, and CSIR-IHBT populations were found to be similar during the first day of distillation. However, during the second day, Rupena, Kugti, Khani, and CSIR-IHBT came under the same ellipse of 0.95% coefficient. The results suggest that the population of Kugti is superior in terms of oil concentration (0.35%), with a higher proportion of patchouli alcohol (63% on the first day). Thus, repeated distillation is recommended for higher recovery of essential oil. Moreover, repeated distillation can be used to attain essential oil with differential and perhaps targeted definite chemical profile.