UPSI Digital Repository (UDRep)
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UPSI Digital Repository (UDRep)
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| Abstract : Perpustakaan Tuanku Bainun |
| The aim of this study was to investigate the essential oil, major constituents, and antioxidant activity of Garcinia urophylla leaf and stem bark. Essential oil was obtained from the leaves using hydrodistillation and its chemical composition was determined by gas chromatography (GC) and gas chromatography mass spectrometry (GC-MS). Phytochemicals were isolated using column chromatography techniques and their structures were elucidated via spectroscopic methods and comparisons with literature data. Antioxidant activity was assessed using the total phenolic content assay and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Results showed that the leaf oil primarily consists of _-caryophyllene (56.2%), _-humulene (26.3%), and _-gurjunene (6.3%). Isolation and purification of the leaves and stem bark extracts yielded eight phytochemicals which were identified as _-mangostin, _-mangostin, _- amyrin, lupeol, lupeol acetate, ferulic acid, syringic acid, and caffeic acid. The hexane leaf extract exhibited the highest phenolic content with 425.9 mg GAE/g, while the isolated lupeol acetate showed the strongest DPPH free radical scavenging activity with an IC50 value of 33.0 _g/mL. In conclusion, the essential oil composition revealed sesquiterpene hydrocarbons as the principal components, whereas phytochemical studies of the leaves and stem barks extracts identified xanthones, phenolics, and terpenes as major compounds. These findings indicate that G. urophylla is a potential source of bioactive compounds with antioxidant properties for the prevention of free radical-related diseases such as atherosclerosis and diabetes. |
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