• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.678-684
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• 2005

Extraction conditions, spectrometric, and sensory properties of pigment extracts from green discolored garlic (GDG) were studied for development of green index to evaluate degree of green discoloration of garlic. GDG pigments were extracted using polar solvents, such as methanol, ethanol, and water. Methanol with 1% HCl resulted in highest extraction of green pigments. Extraction of pigments was affected by temperature, and extracted pigments were partially destroyed at high temperatures. Optimum conditions for extraction of green pigments were $20^{\circ}C$ for 30 min. Because green pigments are unstable at room temperature, and no method has been reported to evaluate degree of green discoloration of garlic, color chart was designed by mixing varying amounts of control and GDG. High correlation was observed between sensory scores and "a" value of color chart samples (y=-3.465x - 11.676) with $R^2$ of 0.993. Green index (GI) was developed based on linear regression equation between sensory scores and "a" values. Sensory panel recognized green discoloration of garlic at $GI{\geq}3.0$. GI developed in this study could be utilized to evaluate degree of green discoloration of garlic during cold storage and distribution of garlic.

• Korean journal of food and cookery science
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• v.16 no.4
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• pp.372-377
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• 2000

Six kinds of herbs(applemint, geranium, lemonbalm, rosemary, sage and thyme) were extracted with water and 95% methanol, and the electron donating ability, antibacterial activity and nitrite scavenging effect were examined. The electron donating ability of herbs ranged from 60.7 to 92.2% and the highest value was observed in geranium, followed by sage and lemonbalm. Antibacterial activity of methanol extracts was much stronger than that of water extracts and gram positive bacteria were more sensitive than gram negative bacteria. Rosemary and geranium exhibited excellent antimicrobial activities against a wide range of bacteria. Nitrite scavenging activity, which was measured at various pH conditions(1.2, 3.0, 3.6, 4.2), was the highest in all herbs at pH 1.2 and the lowest at pH 4.2, suggesting that it is pH dependent. Methanol fraction also provided higher nitrite scavenging effect than the water fraction.

• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.343-348
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• 2010

The surface of low density polyethylene (LDPE) film was oxyfluorinated under different reaction conditions to introduce hydroperoxide groups and change surface characteristics. Hydroperoxide functional groups created by oxyfluorination were used as active sites for graft polymerization with hydrophobic monomer, acryl amide (AM), and hydrophilic monomer, methyl methacrylate (MMA) to carry out the second modification of the LDPE film surface. The surface properties of the OFPE films and grafted OFPE films were characterized by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method, ATR-IR, contact angle measurement and DSC. From the results of DPPH method, the amount of hydroperoxide groups on the oxyfluorinated LDPE film continuously increased as the total pressure in the oxyfluorination and the partial pressure of fluorine gas increased. The water contact angle and surface free energy measurements showed that hydrophilic liquid (water) contact angle on LDPE film surface decreased with hydrophilic AM grafting and hydrophobic liquid (methylene diiodide) contact angle on LDPE film surface decreased with hydrophobic MMA grafting. These were attributed to AM or MMA monomer grafting and the wettability of LDPE filmsurface to hydrophilic and hydrophobic liquids were improved.

• Analytical Science and Technology
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• v.7 no.2
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• pp.187-191
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• 1994

A reactive intermediate 1,2-dihydropyridine derivative 2 has been prepared and isolated from the reaction of pyridine with $^tBuLi$ and trimethylchlorosilane in nonpolar condition at low temperature 2 has characterized by $^1H-NMR$ fine structure analysis with SPINX3. The mechanistic information of formation of 2 was obtained from synthesized 2,5-disubstituted pyridine derivatives 3 and 4.

• Journal of Life Science
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• v.22 no.7
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• pp.958-963
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• 2012

The antioxidant activities of 6 solvent extracts of Artemisia capillaris were evaluated in a dintroflurobenzen (DNFB)-induced allergic mouse model. In vitro antioxidant activities were determined using DPPH and the FRAP test. Methanol (DPPH: 85.87%, FRAP: 1.772) and $dH_2O$ (DPPH: 60.69%, FRAP: 3.185) extracts showed the highest antioxidant activities compared with other solvents (ethyl acetate 41.81%, 0.407, hexane 8.37%, 0.328, etc.). In addition, we tested atopic dermatitis (AD)-like skin lesions in mice treated with DNFB. The methanol extract of A. capillaris on the AD-like skin lesions in DNFB-induced atopy inhibited ear thickness increases (47%) and the skin lesions (45%) compared with a positive control (methanol). The results suggest that they have potential as natural antioxidants and allergy-improving substances and that they may be valuable materials in the functional food or cosmeceutical industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1793-1798
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• 2015

Antioxidant activities of various solvent extracts from Coriolus versicolor were investigated for their total polyphenol content, total flavonoid content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging activity. C. versicolor extracts were produced by organic solvents such as ethanol, ethyl acetate, and methanol. Total polyphenol and flavonoid contents in the ethanol and ethyl acetate extracts were higher than those in the methanol extract. DPPH radical scavenging activity of methanol extract showed the highest value of 80.3%, which was similar to that of ascorbic acid (85.5%). All extracts showed good (>90.0%) ABTS cation radical scavenging activity. The antimicrobial activities of these extracts from C. versicolor were evaluated against six strains of bacteria using the disc diffusion method. All extracts showed antimicrobial activities against all tested bacteria except Staphylococcus aureus. These results indicate that various extracts from C. versicolor could be useful as natural antioxidant and antimicrobial agents.

• Journal of Ginseng Research
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• v.11 no.2
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• pp.118-122
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• 1987

This study was carried out to investigate the effective components, especially saponins, in aerial parts of Panax ginseng. The contents of methanol and ethanol extracts in ginseng leaf were 35.9% and 27.3%, much higher than 15.4% and 8.37% in ginseng root and 21.7% and 16.3% in ginseng stem. And ginseng stem showed as high content of crude fiber as 39.2% which is very high compared with other two parts of ginseng. The contents of total crude saponin were 4.78%, 2.38% and 19.58% in ginseng root, stem and leaf, respectively. In ginseng leaf seven root ginseno-sides-ginsenoside-Rgl(3.32%), -Re(3.24%), -Rd(2.32 %), -Rc(0.65%), -Rb2(0.92%), -Rbl(0.29%), and -Rf(0.11%)-were analyzed by HPLC, Seven gisneno- sides-ginsenoside-Rgl(0.28%), -Re(0.3%), -Rd(0.05%), -Rf(0.01%), -Rc(trace), -Rb2(trace) and -Rbl(trace)-were detected in ginseng stem. Ginseng leaf contained high percentage of saponin and especially of ginsenoside-Rgl, -Re and -Rd. Therefore, ginseng leaf was good resources for ginsenoside-Rgl, -Re and -Rd.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.256-261
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• 1991

To isolate new antioxidants from twelve edible seaweeds, mixed methanol and chloroform extract of marine algae was fractionated into several subfractions and their antioxidant activities were measured by using AOM and 1, 1-diphenyl-2-picrylhydrazyl (DPPH). Especially the aqueous-methanol soluble fractions of brown and red algae showed a considerable antioxidant effect. Their antioxidant activities were stronger than synthetic antioxidants such as BHA, BHT, under the same concentration. Further fractionation of the aqueous-methanol soluble fractions using silica gel column chromatography yielded five subfractions. Among them methanol fraction exhibited high DPPH quenching activities. Also, it was confirmed to be benzene-derivative substances of two compounds by UV, HPLC, GC/MS analysis. Its each molecular weight was about 181, 238. These results suggested the existence of two effective natural antioxidant compounds in three edible marine algae.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.8-12
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• 2005

This study was performed to determine the inhibitory effects on cell survival and Quinone reductase induced activity of Aster yomena (AY) on human cancer cells which, using methanol, was extracted and fractionated into five different solvent types: hexane (AYMH), ethylether (AYMEE), ethylacetate (AYMEA), butanol (AYMB) and aqueous (AYMA) partition layers. The experiment was conducted to determine cytotoxicity of various Aster yomena partition layers on HepG2, HeLa and MCF-7 cells by MTT assay. Among various partition layers of Aster yomena, A YMEE and A YMEA showed the strong cytotoxic effects on all cancer cell lines we used. The Quinone reductase (QR) induced activity on HepG2 cells, A YMH at a does of 100 $\mu$g/mL was 2.46 times more effective compared to the control value of 1.0.

• Korean Chemical Engineering Research
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• v.47 no.1
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• pp.59-64
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• 2009

This study investigated the surface characteristics of polylactic acid (PLA) film after one atmospheric pressure plasma treatment. We used de-ionized water and diiodomethane as polar and non-polar solvents, respectively, for measuring contact angles, and subsequently calculated the surface free energy of PLA film. The contact angle and free energy of PLA surface were optimized at the treatment time of 30 sec, RF-power of 70 W, Ar gas flow rate of 6 lpm and air exposure time of 5 min. We analyzed the change of chemical functional groups on the surface of PLA film through XPS and were able to observe the change of polar functional groups such as -C=O, -CO, -COO on the surface of PLA film after one atmospheric pressure plasma treatment.