Chemical Constituents, Antimicrobial Activity and Nitric Oxide Production Inhibitory Activity of Essential Oil from the Leaves of Croton kongensis Gagnep. Collected from Two Different Locations in Vietnam

In this study, essential oil from the leaves of Croton kongensis Gagnep. from two different locations in Thanh Hoa province, Vietnam, were obtained by hydrodistillation in a Clevenger-type apparatus and characterized by GC/MS analyses. The Nhu Xuan essential oil sample contained sabinene (52.17 %), (E)-caryophyllene (7.23 %), and linalool (6.33 %) as major components, while the Thuong Xuan essential oil sample contained sabinene (12.96 %), camphene (9.45 %), linalool (8.43 %), bornyl acetate (7.99 %), (E)-nerolidol (7.07 %), and (E)caryophyllene (6.53 %). Both essential oil samples showed promising antimicrobial activity against four bacterial and four fungal strains using the broth microdilution method, with minimum inhibitory concentrations (MICs) < 200 mu g/mL. However, the Thuong Xuan essential oil sample exhibited a broader spectrum of antimicrobial activity than the Nhu Xuan essential oil sample. Furthermore, the anti-inflammatory potential study showed that the Thuong Xuan essential oil sample exhibited better inhibition of nitric oxide production induced by lipopolysaccharide in RAW 264.7 cells than the Nhu Xuan essential oil sample, which has IC50 values of 97.32 and 172.67 <mu>g/mL, respectively. These findings provide a theoretical foundation for further investigation and use of the essential oil from C. kongensis leaves in the pharmaceutical and food industries.