• YAKHAK HOEJI
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• v.48 no.1
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• pp.6-12
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• 2004

Near-infrared spectra of methanol-water mixtures and acetonitrile-water mixtures were acquired to find interactions between solvents widely used for reverse-phase liquid chromatography. Mixtures were prepared to give a series of increasing mole fractions of methanol or acetonitrile in water. Data matrices of acquired spectra were analyzed to determine the proper number of principal components of each mixture system using Malinowski's factor indicator function. Initial guess of score matrix and loading matrix were calculated by nonlinear iterative partial least squares (NIPALS) algorithm for faster computation. Iterative target transform factor analysis (ITTFA) was applied to convert the initial estimation of score matrix to true concentration profile and loading matrix to pure spectra of pure components of the mixtures. In case of methanol-water the number of principal components was found to be 4 and those initial guess of factors were converted to the pure spectra of water methanol and two kinds of complexes. In case of acetonitrile-water the number of pure components of the mixtures was found to be 3 and the pure spectrum of acetonitrile-water complex was found. The nonlinear characteristics of concentration profiles of complexes in the solvent mixtures may give a good criteria in understanding their elution characteristics in reverse-phase liquid chromatogrsphy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.305-312
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• 1995

Ixeris dentata was extracted with methanol and then the methanol extract was further fractionated to hexane, chloroform, ethyl acetate, butanol and aqueous fraction. The methanol extract of lxeris dentata had the strong antimutagenic effect on the aflatoxin B1(AFB1) and N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) in Ames mutagenicity test and SOS chromotest. Among the solvent extracted fractions from the methanol extract, the chloroform fraction exhibited the greatest antimutagenic effect suppressing the mutagenicity of AFB1 with inhibition rate of 74 percent. The methanol extract of Ixeris dentata also revealed the inhibitory effect on the growth of MG-63 human osteosarcoma cells after 6 days of breeding at 37℃. The chloroform fraction and the ethyl acetate fraction from the methanol extract of lxeris dentata were most effective and inhibited the growth of MG-63 cells by 97 and 93 percent, respectively. It is suggested that the inhibitory effects of lxeris dentata on the mutagenicity and the growth of MG-63 human osteosarcoma cells are strong in the lipid soluble fractions.

• Korean Chemical Engineering Research
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• v.43 no.3
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• pp.387-392
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• 2005

Recently, dimethyl carbonate (DMC) is considered as an alternative of MTBE (methyl tert-butyl ether), additive for non-leaded gasoline with their fast biodegradation rate and low toxicity. DMC is usually synthesized so far by oxidative carbonylation of methanol, and recently developed synthetic process is also started with methanol. Since the phase equilibria of the system, consisted of DMC and methanol or other reaction products on different temperature and pressure is necessary for the optimum separation process design and operation. However the reported phase equilibria and physical properties for DMC mixtures in the Dortmund Data Bank (DDB; thermodynamic property data bank) are quite rare. Besides, infinitely dilute properties are not found. In this work, isothermal vapor-liquid equilibria at 333.15 K for methanol+DMC binary system and mixing properties, excess molar volume and viscosity deviation at 298.15 K are directly measured and correlated. Additionally, infinitely dilute activity coefficient of methanol in the DMC solvent at three different temperatures are measured and compared with predicted values using modified UNIFAC (Dortmund).

• Journal of the Korean Applied Science and Technology
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• v.34 no.1
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• pp.163-172
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• 2017

The purpose of this study was to measure the bioactivity and antioxidant activity of peel from Gardenia jasminoides Ellis fructus (GJE). GJE have been known to contain functional materials such as crocin, crocetin, geniposide, gardenosid, geniposidic acid, iridoid glycosides etc. We were separated into GJE peel. After that, we determined proanthocyanidin. GJE peel were extracted by 70% methanol, ethyl acetate (EA) and distilled water (DW) of three solvents. To investigate by the solvent extract of flavonoid content and value as a functional food ingredient of GJE peel through antioxidant activities (DPPH radical scavenging activity, ABTS radical scavenging activity, superoxide dismutase like ability, hydroxyl radical scavenging activity, ferrous ion-chelating capacity) were performed. Solvent extract antioxidant activity of increasing concentrations (0.2, 0.4, 0.6 mg/mL) were significantly increased (p<0.05). GJE peel extracts showed lower activity than positive control (ascorbic acid, BHA, EDTA). These results, by a solvent of peel were found that the relationship with the increase of flavonoid content increased physiological activity. The antioxidant activity of the extract from the other except for the EA extract on peel was observed at a high level. The results suggest that GJE peel can be used as nutraceutical foods and natural antioxidant.

• The Journal of Korean Medicine
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• v.27 no.2 s.66
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• pp.122-133
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• 2006

Objectives : The amyloid $\beta$-protein ($A\beta$) is the principal component of the senile plaques characteristic of Alzheimer's disease (AD) and elicits a toxic effect on neurons in vitro and in vivo. Many environmental factors including antioxidants and proteoglycans modify $A{\beta}toxicity$. In this study, we have investigated the protective effects of water- and organic solvent-extracts of Hemerocallis fulva root fractions pre-extracted with methanol on $A\beta$-induced oxidative cell death in cultured rat pheochromocytoma (PC12) cells. Methods : For this study, we used MTT reduction assay for detection of protective effects of water- and organic solvent-extracts of Hemerocallis fulva root fractions pre-extracted with methanol on $A{\beta}_{25-35}$-induced cytotoxicity to PC12 cells. We also used cell-based $\beta$-secretase assay system to investigate the inhibitory effect of water- and organic solvent-extracts of Hemerocallis fulva root on $\beta$-secretase activity. Results : We previously reported that methanol extracts of Hemerocallis fulva root strongly attenuated cytotoxicity induced by the three $A\beta$ fragments ($A{\beta}_{25-35},\;A{\beta}_{1-42}\;A{\beta}_{1-43}$) to both SK-N-MC and PC12 cells. In the present study, we found that butanol-, ethylacetate-, chloroform-, and water-extracts of Hemerocallis fulva root fractions pre-extracted with methanol had strong protective effects against $A{\beta}_{25-35}$-induced cytotoxicity to PC12 cells and inhibitory potency to $\beta$-secretase activity. Conclusion : These results suggest that butanol-, ethylacetate-, chloroform-, and water-extracts of Hemerocallis fulva root fractions pre-extracted with methanol may contain the protective component(s) against $A\beta$-induced cell death in PC12 cells as well as inhibitory component(s) to $\beta$-secretase activity.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.31-36
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• 1997

This study was conducted to investigate the physiological functionality of the hot water, 70% acetone and 70% methanol extracts from the pumpkin. Extraction yield and pH of each solvent extract from various parts of pumpkin were investigated. Extraction yield from flesh were from 63.7% for 70% acetone to 68.2% for hot water. pH of 70% acetone extracts and hot water extracts were 5.01∼5.45 and 5.78∼6.22, respectively, and pH of the flesh part was the highest. The content of soluble solid was the highest in methanol extracts. Flesh part contained the highest concentration of soluble solid. Color of the extracts from fiber was higher than that of other parts. The content of the total sugar was in the decreasing order of flesh, fiber and peel. The content of total polyphenol and flavonoid from each solvent extract of peel was higher than that of other parts. Some differences were observed in physiological functionality of each solvent extracts from various parts of pumpkin. The nitrite scavenging ability of hot water extract from flesh, acetone and methanol extract from fiber and edible portion was higher than other parts. The electron donating ability was the highest in acetone and methanol extracts of peel, methanol extracts of flesh and edible portion, and acetone extracts of fiber.

• Food Science and Preservation
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• v.21 no.2
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• pp.246-253
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• 2014

The objective of this study was to investigate the antioxidative acitivities of various solvent extracts from haw (Crataegus pinnatifida Bunge) pulpy. The Freeze-dried pulpy of haw was extracted with five solvents (70% methanol, 70% ethanol, chloroform:methanol (CM, 2:1, v/v), n-butanol, and ethyl acetate or EA), and the DPPH, reducing power, ferric-reducing antioxidant power (FRAP), ABTS, NO, hydroxyl radical scavenging activity were then measured. The DPPH radical scavenging activity of the 70% methanol and 70% ethanol extracts were 92.89% and 91.17% in the 0.8 mg/mL concentrations, respectively, which were higher than those of the other extracts. The reducing power and FRAP decreased in the following order: 70% methanol, 70% ethanol, n-butanol, EA, and CM extracts. The ABTS radical scavenging activity was high in the 70% methanol and 70% ethanol extracts and low in the n-butanol extract. The NO radical scavenging activity was high in the 70% methanol and 70% ethanol extracts but low in the CM extracts. On the other hand, the hydroxyl radical scavenging activity was high in the n-butanol and 70% methanol extracts but low in the EA extract. These results suggest that the 70% methanol and 70% ethanol extracts from haw will be useful as natural antioxidant and biohealth foods.

• Korean journal of food and cookery science
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• v.24 no.4
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• pp.452-459
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• 2008

The purpose of this study was to investigate the antioxidative effects of Sea tangle powder(STP) solvent extracts as well as Maejakgwa made with STP. The STP solvent extracts were added to soybean oil at a quantity of 0.05%. The solvents used for extraction were methanol, ethanol, ethyl acetate, and petroleum ether. Soybean oil without added STP was used as a negative control, and soybean oil samples containing 0.02% butylated hydroxy toluene(BHT) and $\alpha$-tocopherol were used as positive control, respectively. Each sample was stored at $50^{\circ}C$ for 30 days. The oxidation levels of these samples were determined by measuring their acid values, peroxide values, and thiobarbituric acid(TBA) values. The soybean oil samples containing the STP extracts had lower oxidation levels than both the negative control and $\alpha$-tocopherol positive control, and the sample containing the 0.05% methanol extracts had the lowest oxidation. According to the Rancimat method, the methanol extract(320 min) and ethanol extract(316 min) demonstrated longer induction periods as, compared to the control(253 min), $\alpha$-tocopherol(255 min), and BHT(309 min) samples. For the Maejakgwa, acid values increased over the storage period, however, the samples made with STP had lower values than the control group. Peroxide values increased rapidly for 30 days and then decreased. The TBA values of the Maejakgwa samples made with 3% and 9% STP were lower than those of the 15% STP sample and the control. In conclusion, the oxidative stability of soybean oil containing solvent extracts of STP and Maejakgwa made with STP were increased.

• Korean Chemical Engineering Research
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• v.56 no.3
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• pp.376-380
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• 2018

The astaxanthin recovery efficiencies were compared in acetonitrile, acetone, methanol, dichloromethane : methanol (1:3, v/v) and ethylacetate : ethanol (1:1, v/v) as a extraction solvent after the grinding of the H. pluvialis cells. The astaxanthin extraction yield in acetone was 1.13~1.29 times higher than other extraction solvents. It was also found that 96.7% of astaxanthin accumulated in H. pluvialis could be recovered by a single extraction. Since astaxanthin exists mainly as astaxanthin esters in H. pluvialis, a gradient reversed-phase HPLC analysis was carried out for the separation of astaxanthin esters from the extracts of H. pluvialis. Among the astaxanthin inside the H. pluvialis cell, free astaxanthin was 45.9% and astaxanthin esters were the rest.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.3
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• pp.180-188
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• 2015

To investigate the tendency of $Li^+$ exchange from polar organic solvents, $Li^+$-ion exchange into zeolite Y (Si/Al = 1.56) was attempted by undried methanol (crystal 1) and formamide (crystal 2) solvent. Two single crystals of Na-Y were treated with 0.1 M LiNO3 in each of the two solvents at 323 K, followed by vacuum dehydration at 723 K. Their structures were determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group $Fd{\bar{3}}m$, at 100(1) K. In both structures, $Li^+$ for $Na^+$ ions filled preferentially sites I' and II. The remaining $Na^+$ ions occupied sites I', II, and III' in both structures, in additional to above sites, and $Na^+$ ions occupied site I in crystal 2. While the 68 % exchange of $Li^+$ for $Na^+$ was achieved from undried methanol, only 40 % exchange was observed from undried formamide, indicating that the undried methanol was more effective than undried formamide as solvent for $Li^+$ exchange under the conditions employed.