• Elastomers and Composites
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• 제54권3호
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• pp.188-200
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• 2019

Rubber articles contain various organic additives such as antidegradants, curing agents, and processing aids. It is important to extract and analyze these organic additives. In this paper, various extraction methods of organic additives present in rubber composites were introduced (solvent extraction, Soxhlet extraction, headspace extraction, and solid-phase microextraction), and the extracts were characterized using gas chromatography/mass spectrometry (GC/MS). Solvent and Soxhlet extractions are easy-to-perform and commonly used methods. Efficiency of solvent extraction varies according to the type of solvent used and the extraction conditions. Soxhlet extraction requires a large volume of solvent. Headspace sampling is suitable for extracting volatile organic compounds, while solid-phase extraction is suitable for extracting specific chemicals. GC/MS is generally used for characterizing the extract of a rubber composite because most components of the extract are volatile and have low molecular weights. Identification methods of chemical structures of the components separated by GC column were also introduced.

• 생약학회지
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• 제30권3호
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• pp.275-279
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• 1999

The solvent extracts from Aloe arborescens and Aloe vera were randomly screened for inhibitory effects on the growth of tumor cell lines. In case of Aloe vera extracts, butyl alcohol extract and ethyl alcohol extract showed antitumor activity at $100\;{\mu}g/ml$ on lung cell lines(A427, Sk-mes-1, Calu-3 and 3LL). In Aloe arborescens extracts, butyl alcohol extract and ethyl alcohol extract exerted high activity at $100\;{\mu}g/ml$ on breast cell line(Hs-578T) and lung cell line(Sk-mes-1), respectively. The solvent extracts from Aloe vera exerted antitumor activity broadly on various tumor cell lines. In contract, the solvent extracts from Aloe arborescens exerted specific antitumoricity on a few tumor cell lines.

• 한국응용과학기술학회지
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• 제41권2호
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• pp.520-529
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• 2024

Lycium barbarum extract has a high potential to be developed as a health functional food due to the various health-promoting effects of Lycium barbarum. This study analyzed changes in nutritional and functional components depending on the extraction solvent (purified water and a mixture of purified water and alcohol) and the condition of the sample. The nutritional components (carbohydrates, protein, fat, ash), organic acids, amino acids, total phenolic compounds, and total flavonoids of the extract produced during the extraction process were analyzed. The nutritional composition and functional substances of the extracts showed some differences depending on the type of solvent and the condition of the sample. The amounts of crude protein (7.61%), crude fat (1.63%), carbohydrate (90.22%), and ash (0.54%) of dried Lycium barbarum extract using purified water as a solvent were similar to those of the powder sample extract. The highest content of citric acid was 4.31 mg/mL, similar to the case of acetic acid, when the powder sample used a mixture of purified water and alcohol as a solvent. The highest amino acid content was 357.39 mg/mL when the powder sample was mixed with purified water and alcohol as a solvent. The total amount of phenolic compounds was 686.16 g/L when the powder sample was extracted with a mixture of purified water and alcohol as a solvent. The highest total flavonoid content was 111.32 g/L when the powder sample was extracted with a mixture of purified water and alcohol as a solvent.

• Preventive Nutrition and Food Science
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• 제16권4호
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• pp.321-327
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• 2011

Water, methanol and ethanol extracts of ginseng leaves were assayed for total phenolics and flavonoids, ascorbic acid, cupric and ferrous ion chelating activities, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP) assay and ABTS radical cation decolourization (TEAC) assay for their antioxidant properties. The ethanol extract of ginseng leaves contained significantly (p<0.05) higher amounts of total phenolics and flavonoids (600.57 and 1701 mg/100 g) than methanol (374.43 and 1512.64 mg/100 g) and water extracts (248.30 and 680.05 mg/100 g). Among solvent extracts of ginseng leaves, the ethanol extract showed the most powerful antioxidant activities. However, the ferrous ion chelating activity of ginseng leaf extracts were lower than the cupric ion chelating ability. These differences in concentrations of key antioxidants among various solvent extracts seemed to be responsible for their differences in antioxidant activities. These results suggest that ethanol extract of ginseng leaves has the most effective antioxidant capacity compared to the methanol and water extracts tested in the present study. Thus, it can be applied for the effective extraction of functional material from ginseng leaves for the usage of pharmaceutical and/or food industries.

• 한국식품영양과학회지
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• 제34권1호
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• pp.1-7
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• 2005

DPPH radical 소거 활성은 추출물의 농도가 증가함에 따라 높게 나타났으며, 추출용매별 radical 소거활성은 거의 유사한 경향으로 나타났다. 프로폴리스 추출물의 첨가농도가 증가함에 따라 환원력이 증가하는 경향을 나타내었으며, 특히 50% 에탄을 추출물이 가장 강한 환원력을 나타내었다. 유지에 프로폴리스 추출물을 첨가하여 과산화물가, TBA가 및 산가를 측정한 결과 95% 에탄을 추출물이 가장 높은 산패 억제능을 나타내었다. 프로폴리스 추출물의 농도가 증가함에 따라 아질산염 소거 활성이 증가하였으며, 물추출물 500 $\mu$g을 첨가하였을 때 90%의 가장 높은 활성을 나타내었다. 프로폴리스의 각종 추출물을 이용하여 항균활성을 측정한 결과 50%에탄을 추출물에서 가장 높은 활성을 나타내었으며, 특히 Bacillus subtilis균과 Bacillus cereus균과 같은 그램 양성균에서 높은 활성을 나타내었다. 프로폴리스의 각종 추출물을 이용하여 1, 10 및 100 $\mu$g/mL 농도로 각각 첨가한 후 A549(폐암세포)에 대한 in vitro에서의 세포독성을 조사한 결과 70% 에탄을 추출물 100 $\mu$g/mL를 첨가하였을 때 62.63%의 가장 강한 세포독성을 나타내었으며,95% 에탄올 추출물, 물추출물 및 50% 에탄을 추출물 순으로 나타났다.

• Food Science and Biotechnology
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• 제14권6호
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• pp.715-721
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• 2005

Antioxidant activities of grape seeds extracted with various solvents were evaluated by measuring total phenol and flavanol contents, thiobarbituric acid reactive substances (TBARS) following lipid peroxidation, 2-deoxyribose degradation, SOD-like activity, 2,2'-azino-bis(3-ethylbenzthizaoline-6-sulfonic acid (ABTS) radical-scavenging ability, and electron-donating ability using 1,1-diphenyl-2-pycryl hydrazil (DPPH) method. Total phenol and flavanol contents of mixted-solvent extracts were higher than those of single-solvent extracts, with the mixing ratio of 17:3 (ethyl acetate: water) (EW) showed the highest contents. Antioxidant activities (%) of TBARS following phosphatidylcholine peroxidation were 14, 45, 45, 7, 4, 25, 21, 23, and 20% for ascorbic acid (AA), butylated hyroxytoluene (BHT), quercetin (Q), acetone extract (AT), ethyl acetate (EA) extract, methanol (MeOH) extract, 4:1 (EA) extract, 9:1 (EW)-extract, and 17:3 EW extract, respectively. Antioxidant activities for 2-deoxyribose degradation were 5, 80, 87, 78, 56, 73, 64, 60, and 75% in AA, BHT, Q, AT, EA, MeOH extract, 4:1 EW extract, 9:1 EW extract, and 17:3 EW extract, respectively. MeOH grape seed extract showed distinctly stronger electron-donating activity than other solvent extracts.

• 한국식품영양학회지
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• 제7권4호
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• pp.332-337
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• 1994

The antioxidant activity of solvent extracts isolated from barley leaves was investigated by measuring peroxide value. The fractions of methanol extract obtained from preparative TLC was also studies, with UV-Visible spectrum, total phenol contents and hydrogen donating ability(HDA) The antioxidant activity of various solvent extracts was, in decreasing order, methanol> ethyl ether> methylene chloride $\geq$ ethyl acetate $\geq$acetone> hexane. The antioxidant activity of the fractions of methanol extract was, in decreasing order, fraction 2> fraction 3> fraction 1 and their activity was all superior to that of tocopherol at 500 ppm level. All fraction(1, 2 and 3) exhibited a strong UV absorption at 280 m which would be specifically produced by phenolic compound. UV absorption at 280 m of fraction 2 was greater than those of fraction 1 and 3. In the visible spectrum of these fractions, the maximum .absorption wavelengths of fraction 1, 2 and 3 were 660, 460 and 460 m, respectively. Antioxidant activity of barley leaves seemed to be due to the flavonoids containing phenolic group by UV spectrum and total phenol content.

• 동의생리병리학회지
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• 제31권3호
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• pp.188-193
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• 2017

This study investigated the antioxidant activities of distilled water, ethanol and methanol extracts of Plunus mume flower buds (PFB). The various solvent extracts of PFB were evaluated for their total polyphenol, flavonoid, reducing power and free radical scavenging activities by FRAP and DPPH analysis. The ethanol extract of PFB contained significantly higher amounts of total polyphenols (145 mg GAE/g) and flavonoids (25.43 mg QE/g) than methanol (132 and 25.42) and distilled water (113.6 and 18.04). Among solvent extracts of PFB, the ethanol extract showed the highest antioxidant activities. The 100% ethanol extract of PFB contained significantly higher amounts of total polyphenols and flavonoids than 70% and 50% ethanol extracts. Moreover, the 100% ethanol extract of PFB showed high efficacy in DPPH radical scavenging activity and in collagenase inhibition activity. This results suggest that 100% ethanol extract of PFB has the most effective antioxidant capacity compared to the methanol and water extracts tested in the present study. Thus, it can be applied for the effective extraction of functional material from PFB for usage of cosmeceutical and/or food industries.

• 한국식품영양학회지
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• 제28권5호
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• pp.774-781
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• 2015

The objective of the present study was to determine the total phenol and flavonoid contents and to evaluate the antioxidant potential, of different solvent extracts (ethyl acetate, n-butanol, chloroform, and water) from Robus idaeus in various radical scavenging models (DPPH activity, superoxide dismutase (SOD) activity, reducing power, and nitrite scavenging activity), along with their antimicrobial potential. Measurement of total phenol and flavonoid content of the ethyl acetate extract of R. idaeus was found to be significantly higher than those of the other extracts. The ethyl acetate extract (at a concentration of $1,000{\mu}g/mL$) showed significantly higher reducing power and DPPH radical scavenging activity as compared to the other extracts. Results were dose-dependent. Moreover, the ethyl acetate extract of R. idaeus ($1,000{\mu}g/mL$) showed potent antioxidant efficacy ($85.5{\pm}1.18%$) as evidenced by nitrite scavenging ability at pH 1.2. All solvent extracts of R. idaeus showed lower SOD-like activity (13.72~20.54%). In addition, the antimicrobial activity of all solvent extracts except water extract showed strong inhibition (inhibitory zones in mm) of Staphylococcus aureus ($19.40{\pm}1.00mm$) and Bacillus cereus ($20.50{\pm}0.21mm$) growth. In particular, ethyl acetate extracts (100 mg/mL) showed antimicrobial activity comparable to that of tetracycline (0.01 mg/mL), which was used as a positive control. The results of this study indicate that the ethyl acetate extract of R. idaeus is a natural antioxidant and antimicrobial, with enriched phenols and flavonoids concentration, that has potential in the development of health-enhancing food products.

• 한국식품영양과학회지
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• 제30권2호
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• pp.338-343
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• 2001

The ethanol extract of Quercus mongolica leaf was fractionated by various organic solvents, and their antimicrobial and antioxidative activities were investigated against several microorganisms. The ethanol extract of Quercus mongolica leaf at two thousand $\mu\textrm{g}$ per disc showed 17~21mm inhibition zone against Gram postive and Gram negative bacteria. Among the various solvent fractions from ethanol extract of Quercus mongolica leaf, the hexane fraction showed the strongest antimicrobial activity. Minimal inhibitory concentration (MIC) of hexane fraction was 250$\mu\textrm{g}$/mL against Bacillus cereus, 250~500$\mu\textrm{g}$/mL against Listeria monocytogenes, 500$\mu\textrm{g}$/mL against Staphylococcus aureus, Salmonella typhimurium, Escherichia coli O157, and Pseudomonas aeruginosa. Also, the hexane and chloroform fraction had the similar antioxidative activity compared to that of butylated hydroxy toluene(BHT).