Nephelium lappaceumL. (Rambutan)is a renowned seasonal fruit in Southeast Asia and has been cultivated for centuries in tropical regions. Research on the phytochemicals of this plant arescarce. Rambutan seeds are known to containphenolics and flavonoids as the primary constituents. Unfortunately, the flavonoid structuresin rambutan seeds remainunexamined. This study presents the extraction and structural elucidation of a flavonoid glycoside from the ethyl acetate fraction of N. Lappaceumseeds. Methanol crude extract of N. Lappaceumseeds wasacquired through maceration and subsequently partitioned between n-hexane and ethyl acetate. Various chromatographic methods, such as vacuum liquid chromatography (VLC), column chromatography (CC), and preparative thin-layer chromatography (PTLC), were employed on the ethyl acetate fraction to obtaincompound 1. Phytochemical assays employing 10% NaOH, Shinoda, and 5% FeCl3on compound 1demonstrated the presence of a flavonoid. According to the NMR data (1D and 2D) and HRTOF-MS-ES, compound1was characterised as the flavonoid glycoside,kaempferol-7-O-α-rhamnose or α-rhamnoisorobin.
Marissa et al. (Thu,) studied this question.