• Elastomers and Composites
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• v.51 no.2
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• pp.93-98
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• 2016

The composites of EVA/EPDM including aluminum trioxide (ATH) as a fire retardant were manufactured for the purpose of improving low temperature property and flame resistance in the rubbery materials. The ratio of EVA to EPDM didn't affect the flame resistance of the rubber composites. The addition of ATH resulted in increase of the flame resistance. In the evaluation of the cold resistance, the increasing EPDM content showed enhancement of cold resistance in the composites due to increasing low Tg EPDM. It was found out that tensile strengths of the composites showed a maximum value at 100 phr of ATH by reinforcing effect, but a minimum value at 200 phr of ATH owing to slippage between the flame retardant by the external stress. In the measurement of solvent resistance in tetrahydrofuran, the increasing ATH content yielded enhancement of solvent resistance by reducing swelling of the composite, and increasing EPDM content also resulted from increase of the solvent resistance by reduction of polarizability as well as increase of crosslink in the composites.

• Natural Product Sciences
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• v.16 no.1
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• pp.39-42
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• 2010

The content of hyperin in Acanthopanax species was determined by high performance liquid chromatography (HPLC). Hyperin was quantified by a reverse-phase column with elution program [initially gradient solvent (acetonitrile : water = 85 : 15 to 80 : 20 for 20 min), then isocratic solvent (acetonitrile : water = 80 : 20 for 20 min), and finally gradient solvent (acetonitrile : water = 80 : 20 to 65 : 35 for 20 min)]. UV detection was conducted at 210 nm. The content of hyperin in the fruits of Acanthopanax was measured in the species A. chiisanensis (2.04 mg/g), A. sessiliflorus (1.13 mg/g), A. divaricatus (0.98 mg/g), A. koreanum (0.75 mg/g) and A. senticosus (0.05 mg/g). The content of hyperin in A. chiisanensis was higher than that of other Acanthopanax species.

• International Journal of Industrial Entomology and Biomaterials
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• v.41 no.2
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• pp.36-44
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• 2020

Mulberry root bark is one of potential plant sources for antioxidant materials which can be used for the relief of oxidative stress. To explore the effects of solvent type and temperature on the structural characteristics and antioxidant activity of the root bark extracts, we prepared various extracts of mulberry root bark (Morus alba L.) using 0 - 100 % ethanol (EtOH) at RT - 100℃. EtOH concentration and temperature critically affected the extraction yields, the content of bioactive components, and antioxidant activity of the extracts. Use of high content of EtOH solvent and low temperature resulted in the low extraction yield. Meanwhile, it was revealed that the extract prepared using absolute EtOH at room temperature contained polyphenols and flavonoids with the highest contents among other extracts. Interestingly, the temperature differently affected the polyphenol and flavonoid contents according to the solvent types. In the case of 30% EtOH solvent, polyphenol and flavonoid contents increased with an increase in temperature, whereas in the case of 70 and 100 % EtOH, these contents decreased. Using the radical scavenging assay, it was confirmed that the 100% EtOH extracts had higher antioxidant activity compared to distilled water (DW) extracts regardless of temperature. Also, heating might extract more antioxidant components from the root bark. Especially, the extract prepared using 30% EtOH solvent at 100℃ showed the highest antioxidant activity. Taken together, these experimental results imply that the extraction parameters should be designed carefully considering the productivity, the extracted bioactive components, and antioxidant activity.

• Korean Journal of Pharmacognosy
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• v.39 no.3
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• pp.265-269
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• 2008

This study was carried out to observe the antioxidative activity, fibrinolytic activity, nitrite savenging ability and adenosine content of three medicinal mushrooms. Among water and ethanol extract of each mushroom, water extract of Inonotus obliquus (Czech) showed the highest antioxidative activity $(57.1{\mu}g/ml)$, nitrite scavenging ability (52.04%), fibrinolytic activity (86.8%) and adenosin content $(94.3{\mu}g/g)$, whereas nitrite scavenging ability of ethanol extract of Phellinus linteus showed higher than that of water extract. Apart from the above statements, water was effective than ethanol as extracting solvent in general. These results suggest that Inonotus obliquus (Czech) showed higher activities such as antioxidative activity, nitrite scavenging ability, fibrinolytic activity and adenosin content and water was effective as solvent except for nitrite scavenging ability.

• The Korean Journal of Food & Health Convergence
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• v.4 no.2
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• pp.17-23
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• 2018

Carica papaya is an important medicinal plant used in the management of different disease conditions. Phytochemical screening was carried out using different chemical test, Percentage yield and total phenolic content was evaluated using Folin Ciocalteu method in different solvent system; methanol, ethanol, ethyl acetate, n-butanol and n-hexane respectively. The phytochemical screening of the studies showed the presence of flavonoids, saponins, tannins, terpenoids, glycosides, steroids, carbonhydrate, anthraquinone and alkaloids. The percentage yield of crude extract and total polyphenol content was high in methanol, ethanol and ethyl acetate when compared with n-butanol and n-hexane. The studies show that Carica papaya leave extracts is a potent source of secondary metabolites. The use of the plant in the management of diseases is justified.

• Journal of Pharmaceutical Investigation
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• v.11 no.1
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• pp.6-14
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• 1981

Safety, efficacy and reliability are the three basic criteria that define the quality of any well-designed pharmaceutical dosage form. Content uniformity directly bears on each of the three criteria defining the quality of drug product. Effect of manufacturing methods and physicochemical properties of the drug on content uniformity of tablets was investigated. Chlorpheniramine maleate and micronized salicylic acid were used as main ingredients. Three different methods for incorporation of main ingredients with diluents were solvent mixing method, geometric dilution method, and simple mixing method. The solvent mixing method was the best one of the three.

• Membrane Journal
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• v.14 no.3
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• pp.240-249
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• 2004

Crosslinked PVA membranes were achieved by esterification between the hydroxyl groups of PVA and carboxyl group of sulfosuccinic acid (SSA). SSA containing sulfonic group was used as a chemical crosslinking agent as well as a donor of fixed anionic group ($-SO_3$H). The crosslinking density of membranes was controlled by SSA content and calculated using polar and non-polar solvent. The crosslinking density measured by using non-polar solvent such as xylene and benzene increases with SSA content. However, using the polar solvent such as water and methanol, the crosslinking density increases up to SSA content of 20 wt% and above the content decrease due to sulfonic acid groups. The crosslinked PVA membranes were studied in relation with water diffusion coefficient and mechanical property as well as proton conductivity and methanol permeability as a function of crosslinking density. These properties were all dependent on the effect of SSA content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.338-345
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• 2003

Response surface methodology was used for monitoring changes in phenolic compounds properties of Rubi Fructus extract depening on extraction conditons. The three independent variables (extraction conditions) were ratio of solvent to sample content (5, 10, 15 mL/g), ethanol concentration (20, 40, 60%) and extraction time (2, 4, 6 hr). It was anticipated that each of the five dependent Y variables (responses) would be affected by the three independent variables. The dependent responses were total yield, total phenolics content, electron donating ability, antioxidant ability and nitrite-scavenging ability (pH 1.2, 3.0, 4.2, 6.0). Total yield, total phenolics content, electron donating ability and antioxidant ability were affected by ratio of solvent to sample content. Nitrite- scavenging ability at pH 1.2 and pH 6.0 was affected by ethanol concentration, while it was affected by extraction time at pH 3.0 and pH 4.2. The optimum extraction conditions for total yield were 14.16 mL/g ratio of solvent to sample content,39.08% ethanol concentration and 2.99 hr extraction time. The maximum total phenolics content of extracts were shown at 14.06 mL/g ratio of solvent to sample content, 35.51% ethanol concentration and 3.15 hr extraction time.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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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.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.520-525
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• 1990

A modified method of urea adduct formation, in which water and organic solvent were used as the wetting agent and the reaction medium. respectively, is suggested to obviate methanolysis and to ease recovery in the separation of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil. With the new method the fraction in which the total content of EPA. DHA and their precursors is more than 80% could be obtained. Although the total content of precursors in the concentrate was hardly affected by the kind of the wetting agent or the organic solvent, the content of EPA and DHA varied significantly depending on the organic solvent. This finding made it possible to selectively enrich the desired components. After DHA-enriched fraction (I)HA is 50%) was obtained by using pentane, EPA-enriched fraction ( EPA is 53%)) could be obtained from the residue of DHA-enriched fraction by using heptane.