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64 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGYdried sample. The dried sample was extracted with methanol (MeOH) (3 L %u00d7 3) at room temperature using conventional ultrasound-assisted technique. The extracting solution was then collected and evaporated under reduced pressure to yield 618.5 g methanol residue. The methanol residue was partitioned sequentially with solvents in the order of increasing polarity as following: n-hexane, chloroform, ethyl acetate (each solvent 3 L %u00d7 3). Concentration of the extracted solutions afforded n-hexane extract (150.0 g), chloroform extract (59.0 g), ethyl acetate extract (17.7 g), and methanol extract (360.0 g). The chloroform extract was loaded onto silica gel chromatography column (CC) eluted with a gradient solvent system of chloroform-methanol (100:0 to 0:100, v/v) to afford 11 fractions A-K. Fraction E was fractionated by employing CC over silica gel, eluting with a gradient of n-hexane-acetone (70:1 to 0:100, v/v) to obtain thirteen subfractions, E1-E13.Subfraction E8 was separated on silica gel CC using a gradient solvent system of chloroform-ethyl acetate (100:0 to 0:100, v/v) to yield eight subfractions: E8.1 (19.1 mg), E8.2 (38.7 mg), E8.3 (8.8 mg), E8.4 (71.1 mg), E8.5 (16.6 mg) and E8.6 (7.7 mg). Subfraction E8.1 was purified by using preparation thinlayer chromatography eluted with chloroform-acetone (7:3, v/v) to obtain compound 1 (4.3 mg) and compound 2 (6.5 mg).Vanillic acid (1): White powder solid. 1H-NMR (CD3COCD3): %u03b4H 7.58 (1H, dd, J = 8.2, 1.6 Hz, H-6), 7.56 (1H, d, J = 1.6 Hz, H-2), 6.90 (1H, d, J = 8.2 Hz, H-5), 3.90 (3H, s, 3-OCH3). 13C-NMR (CD3COCD3): %u03b4C 166.7 (1-COOH), 151.2 (C-4), 147.2 (C-3), 123.9 (C-6), 122.1 (C-1), 114.6 (C-5), 112.7 (C-2), 55.4 (3-OCH3).Naringenin (2): White powder solid. 1H- and 13C-NMR (CD3COCD3): see Table 1.