Chemical Constituents Antioxidant and Antibacterial Activities of the Leaves and Flowers from Gardenia carinata Wallich

The essential oil of the leaves was isolated by hydrodistillation and the ethanolic extract of the flowers from Gardenia carinata Wallich. were analyzed for the first time using GC and GC-MS. For the leaves essential oil: Seventeen compounds were detected and eleven compounds were identified, corresponding to 71.10% of the total chromatographical oil compounds. The major constituents were phytol (13.80%), 3-hexene-1-ol, benzoate (12.50%), vitispirane (8.00%), hexadecanal (7.90%), β-damascenone (3.90%) and (E,E)-α-farnesene (3.80%). For the flowers extract: Seventeen compounds were identified, constituting 37.5% of the total chromatographical components. The typical compounds were heneicosane (9.70%), ethyl linolenate (5.70%), squalene (5.70%), 4-allylphenol (5.40%), stigmasterol (2.10%), n-docosane (1.60%), lupenone (1.40%), hexadecanoic acid (0.90%) and compesterol (0.70%). The leaves essential oil showed antibacterial activity against both Gram positive S. aureus with the most potent activity at 18.7 µg/disc, and Gram negative E. coli with an activity of 17.6 µg/disc. The oil was not active against Gram negative P. aeruginosa. The antioxidant activity of the leave essential oil and the ethanolic flower extract were evaluated by using the DPPH and ABTS radical scavenging assay. The leave essential oil showed medium antioxidant activity with the IC50 value of 15.24 ± 0.08 and 10.88 ± 0.05 mg/mL. The ethanolic flower extract possessed high antioxidant activity with the IC50 value of 3.68 ± 0.03 and 2.53 ± 0.03 mg/mL.