• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.643-647
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• 2004

Natural antimicrobial substance from peanut (Arachis hypogaea) shells was isolated and structurally elucidated. Peanut shells were extracted with methanol (MeOH) and concentrated in vacuo, MeOH extract was solvent-fractionated with ethyl acetate (EtOAc) and various buffer to obtain EtOAc acidic, neutral, and phenolic fractions. EtOAc neutral fraction, which showed antimicrobial activity, was purified through silica gel adsorption column, Sephadex LH-20 column, ODS column, and high performance liquid chromatographies, and its active substance was isolated and identified as pratensein (3',5,7-trihydroxy-4'-methoxyisoflavone) by spectroscopic methods of proton-nuclear magnetic resonance, mass spectrometry, and nuclear overhauser enhancement spectroscopy.

• Natural Product Sciences
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• v.26 no.4
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• pp.289-294
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• 2020

Eclipta prostrata is an annual herb, belonging to Asteraceae family, and has been traditionally used to improve immunity and treat hepatitis and bacterial disease in Korea. In this study, a new coumestan glucoside (1) along with ten known compounds (2 - 11) was isolated from E. prostrata. The chemical structures of isolates were elucidated to be wedelolactone-9-O-β-D-glucopyranoside (1), wedelolactone (2), demethylwedelolactone (3), apigenin (4), apigenin-7-sulfate (5), luteolin (6), luteolin-7-sulfate (7), luteolin-7-O-β-D-glucopyranoside (8), pratensein-7-O-β-D-glucopyranoside (9), 3,4-di-O-caffeoylquinic acid (10) and 3,5-di-O-caffeoylquinic acid (11) based on the spectroscopic evidence.