• Applied Biological Chemistry
• /
• v.32 no.1
• /
• pp.44-49
• /
• 1989

To isolate new antioxidants from Panax ginseng, methanol extract of Panax ginseng was fractionated into several subfractions and their antioxidant activities were measured by using ${\alpha}$, ${\alpha}-diphenyl-{\beta}-picrylhydrazyl$(DPPH). Four compounds were isolated from two subfractions that showed high DPPH quenching activities by silica gel, ${\mu}$ Bondapak $C_{18}$ or Sephadex LH-20 column chromatography. The four compounds were confirmed to be phenolic substances by color reaction and UV spectral analysis.

• Korean Journal of Pharmacognosy
• /
• v.25 no.1
• /
• pp.11-19
• /
• 1994

Gleditsia japonica var. koraiensis NAKAI(Leguminosae) is commonly distributed in Korea and has been used as a folk medicine in the treatment of bronchitis, neoplasm and blennorrhgia in the Orient. The aqueous acetone extract of the leaves of G. japonica was subjected to a combination of Sephadex LH-20, Cosmosil $75C_{18}-OPN$, TSK-gel Toyopearl HW 40F, Avicel cellulose, and MCI-gel CHP 20P chromatographies with various solvent systems. Twelve compounds were isolated and confirmed to be vitexin(1), isovitexin(2), orientin(3), isoorientin(4), 4-caffeoyl quinic acid(5), 5-caffeoyl quinic acid(6), 3, 5-dicaffeoyl quinic acid(7), 4, 5-dicaffeoyl quinic acid(8), caffeic acid(9), quercetin(10), isoquercitrin(11) and luteolin-7-O-glucoside(12), on the basis of chemical and spectroscopic evidences.

• Proceedings of the KIEE Conference
• /
• 2001.11b
• /
• pp.106-108
• /
• 2001

As 3V cathode material, a new doping spinel material, LiMn1.6Se0.4O4 powder with a phase-pure polycrystalline was synthesized by a sol-gel method. In spite of Jahn-teller distortion in 3V region($2.4{\sim}3.5V$), the LiMn1.6Se0.4O4 electrode shows no capacity loss. The material in the 3V region initially delivers a discharge capacity of 100mAh/g which increase with cycling to reach 105mAh/g after 90cycles. And 5V cathode material LiNi0.5-xMxMn1.5O4(M=Cr, V, Fe) compounds have been synthesized by sol-gel method. a series of electroactive spinel compounds, LiNi0.5-xMxMn1.5O4(M=Cr, V, Fe) has been studied by crystallographic and electrochemical methods. The material presents only one plateau at around 4.5 V vs. Li/Li+ with a large discharge capacity of 152mAh/g and fairly good cyclability.

• YAKHAK HOEJI
• /
• v.40 no.5
• /
• pp.558-562
• /
• 1996

Betulinic acid and alphitolic acid, the triterpenoids of Zyziphi Fructus, were isolated with silica gel column chromatography and used as the standard substances for the analysis. The compounds were determined with HPLC and HPTLC. They were separated on reversed phase column (Nova-Pak C18) with 0.05M Na2HPO4-methanol (19:81) in HPLC and detected at 210nm. Separation on HPTLC precoated silica gel F254 plates was carried out with chloroform-methanol (6:1) and the separated compounds were reacted with p-anisaldehyde and detected at 540nm. The contents of betulinic acid and alphitolic acid in Zyziphi Fructus from four different regions in Korea were in the range of 2.9~3.8% and 3.2~3.9%, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.11
• /
• pp.5637-5645
• /
• 2012

To enhance the reutilization of waste skate skin for the functional food resources, the investigations of extraction characteristics, antioxidative activity of skate skin water extracts on the oxidation of three cooking oils were carried out, and rheological properties, storage safety and sensory evaluation of collagen gel from skate skin were performed. Aromatic and phenolic compounds contents of $50^{\circ}C$ extracts were higher by 49.4% and 32.7%, respectively, than those of $25^{\circ}C$ extracts. Reducing power of extract at $50^{\circ}C$ was higher by 52.74% than that of $25^{\circ}C$ extract, but was 14.9% of ascorbic acid and 27.8% of BHT. Electron donating ability was corresponded to reducing power and phenolic compounds contents. Antioxidative effect of extracts on cooking oil was higher at $50^{\circ}C$ extract than $25^{\circ}C$ extract, and its order was on corn seed oil, soybean oil and olive oil. Antioxidative effect of $50^{\circ}C$ extract showed 38.27~96.83% and 49.53~75.31% of those of ascorbic acid and BHT, respectively, over three cooking oil. The optimum extraction condition for collagen gellation was $100^{\circ}C$, 2 hours extraction under 2.5 folds hydrolysis, and gel strength was lowered above 50% by 10% seasoning.

• Applied Biological Chemistry
• /
• v.50 no.3
• /
• pp.204-209
• /
• 2007

The objective of this research was to evaluate the inhibitory activities of phenolic compounds isolated from Crataegi Fructus on ${\alpha}-amylase$ and ${\alpha}-glucosidase$. The content of total phenolic compounds of water extract from Crataegi Fructus was 22.5 mg/g. The inhibitory activity of the water extract (200 ${\mu}g/ml$) from Crataegi Fructus on ${\alpha}-amylase$ and ${\alpha}-glucosidase$ was determined to be 100% and 82.6%, respectively. Isolation of inhibitory compounds was carried out on Sephadex LH-20 and MCI-gel CHP-20 column chromatography using a gradient elution procedure of increasing MeOH in $H_2O$. The chemical structure of the inhibitory compound against ${\alpha}-amylase$ and ${\alpha}-glucosidase$ was confirmed as chlorogenic acid by spectroscopic analysis of FAB-MS, NMR and IR spectrum.

• Journal of Applied Biological Chemistry
• /
• v.55 no.4
• /
• pp.217-220
• /
• 2012

The fruits of Acanthopanax sessiliflorus Seeman (Araliaceae) were extracted with 70% aqueous ethanol at room temperature. The concentrated extract was partitioned with ethyl acetate (EtOAc), n-butyl alcohol, and $H_2O$, successively. From the EtOAc fraction, two compounds were isolated through the repeated silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatographies. According to the results of physicochemical and spectroscopic data including NMR, mass spectrometry, and infrared spectroscopy, the chemical structures of the compounds were determined as 3,5-dihydroxycinnamic acid (1) and protocatechuic acid (2). Compound 1 was isolated from the fruits of A. sessiliflirus Seeman for the first time. And the compounds were evaluated for the radical scavenging the antioxidant capacity using 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)diammonium salt, 1,1-diphenyl-2-picrylhydrazy, and oxygen radical absorbance capacity assay.

• Journal of Applied Biological Chemistry
• /
• v.54 no.3
• /
• pp.178-183
• /
• 2011

The stem woods of Lindera obtusiloba Blume were extracted in 80% aqueous methanol and the concentrated extract was partitioned with ethyl acetate (EtOAc), butanol (n-BuOH), and $H_2O$, successively. From the EtOAc and n-BuOH fractions, five compounds were isolated through the repeated silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatographies. On the basis of spectroscopic data including mass spectrometry, IR, $^1H$-NMR, $^{13}C$-NMR, distortionless enhancement by polarization transfer, and two-dimensional-NMR gradient correlated spectroscopy (gCOSY), gradient heteronuclear single quantum correlation (gHSQC), gradient heteronuclear multiple bonding connectivity (gHMBC), the chemical structures of the compounds were determined as asarinin (1), (+)-catechin (2), (-)-epicatechin (3), hyperin (4), and nudiposide (5). Compounds 1 and 5 were isolated for the first time from the stem wood of L. obtusiloba Blume.

• Journal of Applied Biological Chemistry
• /
• v.64 no.4
• /
• pp.343-349
• /
• 2021

The rhizomes of Cnidium officinalis were extracted in aqueous MeOH, and the concentrate was fractionated via systematic solvent fractionation to EtOAc, n-BuOH, and aqueous fractions. The repeated column chromatography of EtOAc and n-BuOH fractions using silica gel, octadecyl silica gel, and Sephadex LH-20 as stationary phase to afford five lipids. They were identified to be methyl linoleate (1), linoleic aicd (2) 6-linoleoyl-𝛼-D-glucopyranosyl 𝛽-D-fructofuranoside (3), 1-linolenoyl-3-(𝛼-D-galactopyranosyl (1→6)-𝛽-D-galactopyranosyl) glycerol (4), and 1-linoleoyl-3-(𝛼-D-galactopyranosyl (1→6)-𝛽-D-galactopyranosyl) glycerol (5) on the basis of spectroscopic data such as IR, MS, and Nuclear magnetic resonance (NMR). Compounds 1 and 3-5 were isolated for the first time from this plant in this study. The NMR data of fatty acids 1 and 2 reported in literatures are different each other. Authors identified the NMR data without ambiguity. Compound 3, a conjugate of sucrose and fatty acid, and compounds 4 and 5, digalactosyl monoglyceride, are very rarely occurred in natural source. Through the immune enhancement and anticancer activity of the reported lipid compounds, the potential as various pharmacologically active materials of Cnidium officinalis rhizome can be expected.

• Natural Product Sciences
• /
• v.22 no.1
• /
• pp.64-69
• /
• 2016

A method for simultaneously identifying antioxidative compounds was developed using time-based LC-MS coupled with DPPH assay regardless of the time consuming process. The methanolic extract of Polygonum aviculare (Polygonaceae) showed significant DPPH radical scavenging activity. Time-based DPPH assay for simultaneous identification of active compounds from the extracts of P. aviculare was used. Major peaks of ethyl acetate fraction of P. aviculare showed high DPPH radical scavenging activity. A simple phenolic compound (1) and six flavonoids (2-7) were isolated from the ethyl acetate fraction of P. aviculare by silica gel and sephadex LH-20 column chromatography. The structures of seven compounds were determined to be protocatechuic acid (1), catechin (2), myricitrin (3), epicatechin-3-O-gallate (4), avicularin (5), quercitrin (6), and juglanin (7) based on the analysis of the $^1H$-NMR, $^{13}C$-NMR and ESI-MS data. All compounds exhibited significant antioxidant activity on DPPH assay and active compounds were well correlated with predicted one.