Phytochemical profiling of the essential oils from three species and their and dengue protease inhibition activity.

The chemical compositions, and anti-dengue activity of the essential oils of the rhizomes of Linn., Roxb., and Roxb. had been investigated. The oil was mainly composed of ar-turmerone (54.0%) and curlone (17.7%), while the oil was rich in curzerenone (23.4%), 1,8-cineole (21.2%), and camphor (7.1%). Xanthorrhizol (21.6%), β-curcumene (19.5%), ar-curcumene (14.2%), and camphor (9.2%) were the major compounds in the oil. Among the oils, the oil was found to be the most active NSB-NS3 protease inhibitor (IC 1.98 μg/mL). PLS biplot disclosed that the essential oils were classified into three separated clusters based on their characteristic chemical compositions, with positioned closest to the anti-dengue activity. Four compounds from the oil have both hydrogen and hydrophobic bonds that could be responsible for the DENV-2 NS2B-NS3 inhibitory effect.