Essential Oils From Chromolaena odorata (L.) R. M. King and H. Robinson Stem Barks and Leaves: Chemical Analysis, Biological Activity and In Silico Approach.

The current study first describes the chemical profiles of essential oils from Vietnamese Chromolaena odorata fresh stem barks and leaves. The gas chromatography-flame ionization detection/mass spectrometry (GC-FID/MS) analysis revealed that α-pinene (6.97%-38.91%), β-pinene (5.68%-11.64%), geijerene (10.60%-26.68%), germacrene D (9.33%-16.87%), and (E)-caryophyllene (5.03%-9.12%) were the major compounds. Essential oils showed strong anti-inflammation against NO (nitric oxidative) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells with IC values of 42.44-49.01 µg/mL. Two essential oils also exhibited cytotoxicity against four cancer cell lines, K562, HeLa, HepG2, and MCF-7, antioxidant activity to capture DPPH radicals, and antidiabetics in α-glucosidase inhibition. Both samples showed varying levels in the antimicrobial experiment, especially the leaf essential oil, which showed strong antibacterial activity against the bacterium Bacillus subtilis with a MIC value of 64 µg/mL. From the molecular docking investigation, geijerene had a higher affinity for cyclooxygenase-2 (COX-2) than the other main compounds, whereas germacrene D had the strongest binding affinity for two protein targets, COX-2, and B. subtilis FtsZ. It was discovered that the main factor stabilizing the bindings of these compounds to the target proteins was hydrophobic interactions.