• Natural Product Sciences
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• v.7 no.3
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• pp.72-75
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• 2001

The antioxidant activity of roasted defatted perilla (Perilla frutescens) seed was determined by measuring its radical scavenging effect on 1,1-diphenyl-2- picrylhydrazyl (DPPH) radicals, inhibitory activity on total reactive oxygen species generation in kidney homogenates using 2',7'-dichlorodihydro-fluorescein diacetate, and scavenging effect on authentic peroxynitrites. The methanolic extract of roasted defatted perilla seed showed strong scavenging activity in both DPPH and peroxynitrite radicals, and thus fractionated with several solvents. The antioxidant activity potential of the individual fraction was in the order of ethyl acetate>n-butanol>dichloromethane>water>n-hexane fraction. The ethyl acetate soluble fraction exhibiting strong antioxidant activity was further purified by repeated silica gel and Sephadex LH-20 column chromatography. Luteolin was isolated as one of the active principles from the ethyl acetate fraction, together with the inactive chrysoeriol and apigenin.

• Ocean and Polar Research
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• v.39 no.2
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• pp.115-124
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• 2017

The objective of this study is to evaluate the antioxidant activity of the fruits of Ligustrum japonicum. The crude extract was successively fractionated into n-hexane, 85% aqueous methanol (85% aq.MeOH), n-butanol (n-BuOH), and water fractions by means of solvent polarity. The crude extract and its solvent fractions were evaluated for their antioxidant effect by four different assay systems: scavenging power on peroxynitrite and intralcellular ROS produced in HT-1080 cells; DNA oxidation inhibition; ferric reducing antioxidant power (FRAP). The n-BuOH fraction exhibiting potent antioxidant activity was further purified by C18 silica gel column chromatography and RP-HPLC to give tyrosol (1) and salidroside (2). The structure of isolated compounds was determined by extensive 2 D NMR experiments such as $^1H$ COSY, NOESY, HSQC and HMBC as well as by comparison with the published spectral data.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.2
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• pp.120-127
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• 2003

Cyclodextrin glucanotransferase (CGTase) from Bacillus stearothermophilus synthesized vanillin and ethyl vanillin monoglucoside, with a series of its maltooligoglucosides by transglycosylation with dextrin as a donor, and vanillin or ethyl vanillin as an acceptor. The monoglucoside formed from reaction mixture of vanillin or ethyl vanillin by the successive actions of CGTase and Rhizopus glucoamylase was isolated by extraction with n-butanol saturated with water and silica gel column chromatography. The structure of the isolated monoglucoside was identified as vanillin- $\alpha$ -D-glucoside and ethyl vanillin- $\alpha$ -D-glucoside, respectively, by FAB-MS, UV, IR, 1H-NMR, 13C-NMR spectra and products by hydrolysis with acid, $\alpha$ - and $\beta$ -glucosidases.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.131-131
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• 1998

In the course of screening for new natural compounds having antioxidant activity from microbials, mushrooms as well as plants. We have isolated novel sesquiterpenoid and officinalic acid from methanolic extracts of Stereum ostrea. The dried fruit body( 450 g) of Stereum ostrea was extracted with methanol, then methanolic extract was partitioned between water and hexane, chloroform, and ethyl acetate, subsequently. The chloroform extract was subjected on silica gel, Sephadex LH-20 and RP-18 column chromatography, successively. And two compounds were isolated and identified as new triterpenoids and officinalic acid using $^1$H - NMR, $\^$13/C - NMR as well as Mass spectra.

• Journal of Food Hygiene and Safety
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• v.14 no.2
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• pp.153-159
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• 1999

This study was undertaken to evaluate antioxidative activities of substances isolated from marine resources against human low density lipoprotein (LDL). Methanol-water extract(80 : 20, v/v) of Sargassum ringgoldianum had the highest antioxidant activity and the active substance was purified by silica gel column chromatography by eluting chlorform : methanol mixture (80 : 20 v/v). The active fraction was seperated to several spots on the TLC in chlorofrom : methanol (10 : 1, v/v) mixture. Antioxidative activity of band 4 of fraction 2 on TLC was highest than that of $\alpha$-tocopherol against human LDL oxidation by the method of thiobarbituric acid reactive substance (TBARS). The band 4 of fraction 2 inhibited the copper mediated oxidation of human LDL with almost completely at 1 or 2 mg/ml.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.118-119
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• 2016

γ-C₂S is known as a kind of substance that it does not react with water at room temperature. However it could react with the CO₂ producing CaCO₃ and silica gel as the carbonation products. Thus γ-C₂S can be used as a mineral addition to improve the compressive strength and durability of concrete. On the other hand, the manufacture of γ-C₂S can give an effective utilization of industrial by-product with low energy consumption and low CO₂ emission. This paper aims to summarize the development situation on this field.

• Bulletin of Food Technology
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• v.7 no.2
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• pp.64-73
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• 1994

Using 20 lipases from various microbial origins medium chain glycerides, namely, mono-, di-, and tri-carproyl glycerols from glycerol and acid were synthesized in isooctane. Enzyme reaction was performed at 0.35 M of capric acid, 0.025M of glycerol and the same mass of silica gel to remove water in 5ml of isooctane with 30mg of lyophilized lipase. Among 20 lipases, eleven lipases showed good synthetic activities, especially lipase from Pseudomonas aeruginosa (Lipase PS), Rhizomucor miehei origined lipase and Chromobacterium viscosum lipase (Lipase CV) showed good activities for production of tricaproylglycerol, while Lipase OF-360 (origined from Candida rugosa) and Lipase D (Rhizopus delemar) were good for production of dicaprolyglycerol. The lipases, especially Lipase PS, have high thermal stability at $ 60^{circ}C$, and optimum pH of lyophilization for dehydrating the lipase was pH 6.5.

• Archives of Pharmacal Research
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• v.29 no.2
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• pp.178-182
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• 2006

Four crystal forms of cephradine were isolated by recrystallization and characterized by powder X-ray diffractometry, differential scanning calorimetry, and thermogravimetric analysis. The dissolution patterns of four crystal forms of cephradine were studied in water at $37{\pm}0.5^{\circ}C$, 90 rpm for 120 min. The amount dissolved at 120 min was highest for Form 1 ($100\%$), followed by Form 3 ($98.9\%$), Form 4 ($77.83\%$), and Form 2 ($75.55\%$). After storage for two months at $0\%$ RH (silica gel, $20^{\circ}C$), $52\%$ RH (saturated solution of $Na_{2}Cr_{2}O_{7}{\cdot}2H_{2}O/20^{\circ}C$), and $95\%$ RH (saturated solution of $Na_{2}HPO_{4}/20^{\circ}C$), none of the crystal forms showed transformation.

• YAKHAK HOEJI
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• v.22 no.4
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• pp.238-241
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• 1978

A simple and convenient method of detecting N, N-dimethy laniline (D.M.A.) residues in ampicillin trihydrate (A.T.) was established. D.M.A. was extracted by chloroform from the chloroform presaturated N/10-ammonia water solution of A.T. and chromatographed on silica gel G thin layer. Blue spot appeared in 15minutes after spray of 2, 6-dichloroquinonechlorimide solution was compared with the blue spot of reference concomitantly processed. The developing solvent was prepared by mixing equal volume of cyclohexane and chloroform. To quantitate the amount of D.M.A. in A.T., T.L.C. was performed with the Eastmann Chromatogram sheet, then color density was measured by Cosmo Superclick densitometer. The developing solvent at this time was cyclohexane-chlorofonn (3+7) mixture. The peak areas obtained with the amount of D.M.A ranging from 0.05 to 2.0 .mu.g were linear to color density. Better sensitive results would be available with the densitometer equipped with monochromator.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.436-439
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• 1998

In order to find out anti-platelet activating factor (PAF) from natural resources, Korean medicinal plants used for the treatments of peripheral circulation disorders were tested for their possible protective effects on PAF-induced anaphylactic shock. From the above screening, the methanol extract of Gentiana scabra showed a potent antagonistic activity against PAF. Water suspension of the extract was partitioned with $CH_2$$CI_2$ and EtOAc, successively. The EtOAc fraction which showed the highest activity was chromatographed on silica gel to yield 6 fractions. From the fraction which showed higher PAF-antagonistic activity than the other fractions, compound 1 was isolated by recrystallization. On the basis of spectral data, compound 1 was identified as 2-hydroxy-3-methoxybenzoic acid glucose ester. The compound prevented the mice from the PAF-induced death at a dose of 300 $\mu\textrm{g}$/mouse.