| dc.description.abstract | The isolation and identification of flavonoid compounds from the bark of
Casuarina cunninghamiana Miq. have been carried out through several stages,
beginning with maceration extraction using methanol as the solvent, followed by
partitioning with ethyl acetate and n-hexane. The ethyl acetate extract was then
evaporated and analyzed using Thin Layer Chromatography (TLC) to determine the
optimal solvent system. Compound isolation was performed using column
chromatography with silica gel as the stationary phase and a mixture of
chloroform:ethyl acetate (90:10; 80:20; 70:30; 60:40; 50:50; 40:60; 30:70; 20:80;
10:90 v/v) as the mobile phase.The isolated compound was obtained as a yellow
orange amorphous solid weighing 5.5 mg, with an Rf value of 0.53 using
chloroform:ethyl acetate (30:70 v/v) as the eluent. Based on UV-Visible
spectrophotometric analysis in acetone solvent, two major absorption peaks were
observed at maximum wavelengths (λmax) of 282 nm (band II) and 315 nm (band I).
The FT-IR spectrum showed the presence of hydroxyl (–OH), ketone carbonyl (C=O),
aromatic C=C, C-H, C-O, C-O-C, and sp² C-H groups at absorption bands of 3427.08
cm⁻¹, 1695.21 cm⁻¹, 1581.63 cm⁻¹, 1381.03 cm⁻¹, 1284.59 cm⁻¹, 1124.50 cm⁻¹, and
704.02 cm⁻¹. Meanwhile, the ¹H-NMR data showed meta-coupled aromatic doublet
proton signals of H-6 (δ 6.9321–6.9279 ppm) and H-8 (δ 6.9561–6.9598 ppm), a
doublet of doublet at δ 7.60–7.72 ppm corresponding to H-2′, H-5′, H-3′, and H-6′,
and a singlet signal at δ 7.03 ppm corresponding to the H-3 position, which is
characteristic of flavones. Overall, the spectroscopic data indicate that the isolated
compound belongs to the flavonoid group, specifically a flavone. | en_US |
