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SECTION I: MOLECULAR GENETIC ENGINEERING AND BIOCHEMICAL TECHNOLOGY 231wavelengths, 254 nm and 366 nm, using a 10% H2SO4 solution in ethanol as a reagent, heated gradually on an electric stove until color developed.Column Chromatography (CC): Column chromatography was conducted using silica gel (0.040-0.063 mm, Merck) as the stationary phase and RP-18 (0.040 mm, Merck) and Diaion%u2122 HP20 resin (Misubishi) as the mobile phase.Nuclear Magnetic Resonance (NMR) Spectra: 1H-(500 MHz) and 13C-(125MHz) spectra were recorded on a Bruker AM500-FTNMR machine using TMS as the internal standard.2.3. Extraction and Isolation of CompoundsThe avocado leaves, after harvesting, were dried and then ground to obtain 2 kg of powdered leaves. The sample was extracted with ethanol at 500C, three times, each for 4 hours. The extract was combined, filtered through filter paper and the solvent was removed under reduced pressure, yielding 160g of total extracts. From the 160g of total extracts, sequential partitioning was performed using n-hexane and ethyl acetate as solvents, with each solvent extracted three times. The extracts were combined and the solvents were removed under reduced pressure, resulting in corresponding extracts: n-hexane extracts (35g), ethyl acetate extracts (50g) and water extracts (75g).The ethyl acetate extracts (50g) was subjected to separation through column chromatography on normal phase silica gel, with a gradient solvent system of n-hexane:acetate (50:1, 10:1, 5:1, 1:1, 100% EtOAc), yielding 5 fractions labeled E1 to E5.Fraction E2 was separated using normal phase silica gel column chromatography, with a solvent system of n-hexane:EtOAc (10:1), yielding 5 fractions labeled E2.1 to E2.5. Fraction E2.2 was separated using normal phase silica gel column chromatography, with a solvent system of n-hexane:EtOAc (5:1), yielding 4 fractions