New Monoterpene Acid and Gallic Acid Glucose Esters with Anti-Inflammatory Activity from Blue Gum (Eucalyptus globulus) Leaves
Date of Original Version
Blue gum (Eucalyptus globulus) is a widely used botanical in the cosmeceutical and food industries. Although blue gum leaves are known for abundant essential oils, their nonvolatile phytochemical constituents and bioactivities remain unclear. Herein, a phytochemical investigation of blue gum leaves led to the identification of eight new monoterpene acid and gallic acid glucose esters (1-4 and 14-17; glubosides A-H, respectively) and 12 known analogues (5-13 and 18-20). Their structures were determined based on extensive spectroscopic data analysis, chemical degradation, and chiral separation. Oleuropeic acid conjugated glucose esters (1-13, 15, 16, 18, and 20) are reported as epimeric mixtures. Compounds 7, 12, 14, 19, and 20 (at 30 μM) inhibited nitrite release in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Compounds 7 and 14 (at 3-30 μM) also down-regulated proinflammatory biomarkers, including cytokines (TNF-α, IL-6, and IL-1β), protein expression (iNOS and COX-2), and transcription factor nuclear translocation (NF-κB) in LPS-stimulated RAW264.7 cells. This work highlights the anti-inflammatory potential of phytochemicals from blue gum leaves, which supports their further development as cosmeceutical and/or nutraceutical products.
Journal of Agricultural and Food Chemistry
Liu, Wei, Minglei Li, Guihua Wang, Hang Ma, Yu Mu, Dan Zheng, Xueshi Huang, and Liya Li. "New Monoterpene Acid and Gallic Acid Glucose Esters with Anti-Inflammatory Activity from Blue Gum (Eucalyptus globulus) Leaves." Journal of Agricultural and Food Chemistry 70, 16 (2022): 4981-4994. doi:10.1021/acs.jafc.2c00828.