• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1206-1212
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• 2010

This study was performed to establish optimum extraction condition of Tricholoma matsutake. A central composite design was applied to investigate the effects of independent variables, extraction temperature ($X_1$), extraction time ($X_2$) and water per sample ($X_3$) on dependent variables such as soluble solids contents ($Y_1$), total phenolics contents ($Y_2$), reducing sugar contents ($Y_3$), electron donating ability ($Y_4$) and nitrite scavenging ability ($Y_5$). The optimum extraction conditions were predicted and monitored by response surface methodology using SAS program based regression analysis. Soluble solids content, electron donating ability and nitrite scavenging ability were highly affected by water per sample. However, the contents of total phenolics and reducing sugar were affected by water per sample and extraction temperature as well. The optimum extraction conditions for soluble solids were 34.84 mL/g (water/sample) at $78.85^{\circ}C$, for 3.33 hr. In contrast, the optimum extraction conditions of electron donating ability were temperature of $91.00^{\circ}C$, time of 1.62 hr and water per sample of 39.42 mL/g. Taken together, the optimum ranges for hot water extraction of Tricholoma matsutake were $70{\sim}90^{\circ}C$, 2~4 hr and 30~50 mL/g.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.268-275
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• 2013

This study was performed to investigate the antioxidant activity of cherry added into meat products. Water and methanol were used to extract the antioxidant compounds from cherry. Total phenolic compounds of the methanol and water extract of cherry were 2.17 g/100 g and 2.77 g/100 g, respectively. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of methanol extract showed similar activities to those with ascorbic acid at all concentrations (from 0.1% to 2.0%). Especially, water extract of cherry showed similar activity to those of ascorbic acid (AA), and methanol extract, when 2% of cherry extract was added. The reducing power of cherry was not comparable to those with AA, however no differences in reducing power were observed between the water and methanol extract. The iron chelating ability of cherry was observed in the range of 17.8-94.0% at both water and methanol extracts. An increased iron chelating ability was observed with increased concentration up to 2%. Iron chelating ability for water extract of cherry tended to be lower than those with methanol extract. After pork patties were manufactured with methanol extract of cherry at 0.5 and 1.0%, physicochemical properties, lipid oxidation and microbial changes of patties were measured. The addition of methanol extract of cherry reduced pH, brightness, redness, yellowness and thiobarbituric acid reactive substance (TBARS). During 14 d of storage, pH, TBARS and microbial counts were increased, while redness and yellowness values were decreased. Since the addition of methanol extract of cherry lowered TBARS during storage, it could be used as a natural antioxidant in meat products.

• Journal of Korea Water Resources Association
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• v.50 no.11
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• pp.715-723
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• 2017

Extracellular Polymeric Substances (EPS) in the water environment assemble fine, colloidal particles, such as clays, microorganisms and biomass, in large flocs, which are eventually subject to sedimentation and deposition and determine water/sediment quality and quantity. This study hence aimed to investigate the way that water and colloidal chemistry affects EPS-mediated flocculation of colloidal particles, using a jar-test experiment. Especially, ionic strength, divalent cation and humic substances concentrations were selected as experimental variables in the jar-test experiments, to elucidate their effects on EPS-mediated flocculation. A higher ionic strength increased flocculation capability, reducing electrostatic repulsion between EPS-attached colloidal particles and enhancing particle aggregation. 0.1 M NaCl ionic strength had higher flocculation capability, with 3 times larger floc size and 2.5 times lower suspended solid concentration, than 0.001 M NaCl. Divalent cations, such as $Ca^{2+}$, built divalent cationic bridges between colloidal particles and EPS (i.e., $colloid-Ca^{2+}-EPS$ or $EPS-Ca^{2+}-EPS$) and hence made colloidal particles to build into large, settelable flocs. A small $Ca^{2+}$ concentration enhanced flocculation capability, reducing suspended solid concentration 20 times lower than the initial dosed concentration. However, humic substances, adsorbed on colloidal particles, reduced flocculation, because they blocked EPS adsorption on colloidal particles and increased negative charges and electrostatic repulsion of colloidal particles. Suspended solid concentration in the tests with humic substances remained as high as the initial dosed concentration, indicating stabilization rather than flocculation. Findings about EPS-mediated flocculation in this research will be used for better understanding the fate and transport of colloidal particles in the water environment and for developing the best management practices for water/sediment quality.

• Journal of the Korea Concrete Institute
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• v.18 no.2 s.92
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• pp.205-211
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• 2006

The objective of this study was to evaluate the durability of low shrinkage high performance concrete(LSHPC), which was combined with expansive additives and shrinkage reducing admixtures. We tested for not only LSHPC but also high performance concrete(HPC) and normal concrete(NC) to be compared with the durability of LSHPC. HPC was made in the same water-binder ratio of LSHPC without expansive additives and shrinkage reducing admixture. As a result, it was found that LSHPC had higher compressive and tensile strength than that of HPC. LSHPC showed more excellent performance than HPC and NC in the case of resistance to chloride ion penetration and resistance to carbonation and also showed nearly 100 durability factor in the freeze-thawing test with 500 cycles. From the examination about the watertightness and the pore distribution, it was found that the durability of LSHPC was improved because its hardened cement paste is organized closer. So we can conclude that when LSHPC is applied to structures in field, it is possible to reduce the shrinkage and crack in concrete and improve the durability.

• Journal of the Korean GEO-environmental Society
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• v.10 no.4
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• pp.5-13
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• 2009

The runoff-reducing facilities using infiltration was considered for the sustainable and sound water management. However, for practical utilization, many problems are attended and therefore effort on improvements are required. In this study, methods of improvement for infiltration facilities proposed by Infiltration-Storage System (ISS) and the effect of runoff reduction were analyzed by hydraulic experimental study. In order to analyze the infiltration characteristics of proposed runoff reduction facilities in this study, it was applied to various rainfall condition and surface material considering development and urbanization influences. As a results of hydraulic model experiment, Infiltration-Storage System (ISS) made addition to effect of reduction by lower layer of accumulative infiltration quantities. And then as rainfall-intensity was increased, accumulative infiltration rates were increased in this study. Thus, Infiltration-Storage system (ISS) was more efficient than existing runoff reduction facilities because of increasing infiltration rate. Such a result was guaranteed application of ISS as runoff-reducing facilities. Therefore, ISS is expected to be capable for practical application if subsequent research for improvements are followed. Additionally, results of this study are expected to provide fundamental research data on infiltration facilities.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.60-64
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• 2006

The effect of far-infrared (FIR) irradiation and heat treatment on the antioxidant activity of extracts from citrus pomaces (CP) was evaluated. CP were placed in pyrex petri dishes (8.0 cm diameter) and irradiated at $100^{\circ}C$ and $150^{\circ}C$ for 5, 10, 15, 20, 40 or 60 min with a FIR heater or simple heater, respectively. After FIR irradiation or simple heat treatment, 70% ethanol extracts (EE) and water extracts (WE) of CP were prepared and radical scavenging activity (RSA) and reducing power of the extracts were determined. The antioxidant activities of the extracts increased as the time of heating or FIR-irradiation increased. When CP were FIR-irradiated at $100^{\circ}C$ far 30min, the values of RSA and reducing power of EE increased from 14.9% to 44.2%, and 0.290 to 0.886, respectively, compared to the untreated control. Simple heat treatment of CP at $100^{\circ}C$ for 60 min also increased RSA and reducing power of EE to 44.7%, and 1.045, respectively. FIR irradiation and heat treatment increased RSA and reducing power of WE from CP, too. These results indicated the antioxidant activity of CP extracts was significantly affected by FIR irradiation and heating temperature and duration on CP, and that the FIR irradiation and heat treatment process can be used as a tool for increasing the antioxidant activity of CP.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.205-212
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• 2014

This study was designed to investigate the antioxidant activities (ORAC value, DPPH and ABTS radical scavenging activity, FRAP activity, and reducing power) and nitrite scavenging activities of Acanthopanax senticosus extracts fermented with the mycelia of three different mushroom species: Ganoderma lucidum, Phellinus linteus, and Hericium erinaceus. The highest total phenol content (42.09 GAE mg/g) and ORAC value ($74,912{\mu}M$ TE/g) were observed in a hot water extract of A. senticosus fermented with G. lucidum. The highest DPPH radical and nitrite scavenging activities were observed in a 70% ethanol extract of A. senticosus fermented with G. lucidum. In addition, ABTS radical scavenging activity (8-88%), FRAP activity (0.1-0.2), and reducing power (0.3-0.7) were increased by ethanol addition in all samples in a dose-dependent manner. These results provide a basic understanding of the antioxidant and nitrite-scavenging activities of A. senticosus extracts fermented with different mushroom mycelia.

• Food Science and Preservation
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• v.10 no.4
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• pp.540-546
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• 2003

Biological activities of solvent fractions obtained from Cnsicum annuum leaves, being used in material of functional food, were examined by the methods of DPPH scavenging activity, reducing power, nitrite scavenging activity, antimicrobial activity and inhibitory effect on tyrosinase activity. The highest yield was obtained from water fraction, where as the lowest yield was obtained from ethyl acetate traction, 16.9% and 0.6%, respectively. Hydrogen donating activity of Capsicum annuum leaves in increased with increasing amount of extract. Reducing power of the ethyl acetate fraction is increased as the amount of extract is increased. Even in the presence of 900 $\mu\textrm{g}$ of ethyl acetate fraction, reducing power was significantly higher than it was fer the control in which there was no extract. Among the various solvent fractions, ethyl acetate fraction showed the strongest scavenging effect on hydrogen peroxide. Nitrite scavenging effects of all concentrations diminished at higher pH, while in the case of pH 1.2, it showed a nitrite scavenging effect of more than 90% at concentration above of ethyl acetate fraction 500 $\mu\textrm{g}$. Among the various solvent fractions from methanol extract of Capsicum annuum leaves, ethyl acetate and butanol fraction showed the strongest antimicrobial activity. Antimicrobial activity of ethyl acetate fraction was 20 mm against Bacillus cereus, 18 mm against Staphylococcus aureus and 17 mm against Streptococcus mutans. Ethyl acetate fraction showed the strongest of inhibitory activity of tyrosinase.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.357-364
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• 2022

In this study, antioxidant efficacy was analyzed to verify the value of use as an antioxidant-related functional cosmetic material using Cheongtaejeon tea extract. Cheongtaejeon tea was extracted, concentrated, and freeze-dried with hot water and 70% ethanol as a solvent to prepare samples, and then ABTS⁺ radical scavenging activity, electron donating ability, SOD-like ability, reducing power, ferric reducing antioxidant power (FRAP), total phenolic, and flavonoid contents were analyzed. In the ABTS⁺ radical scavenging activity experiment, both the Cheongtaejeon hydrothermal extract (CTW) and the Cheongtaejeon 70% ethanol extract (CTE) showed erasure activity of more than 98% at a concentration of 1,000 ㎍/mL, and in the electron donating analysis experiment, CTW and CTE, respectively, 42.20% and 78.82%. As a result of SOD-like activity measurement, activity of 39.73% and 67.39% of CTW and CTE, respectively, was confirmed. In the case of FRAP and reducing power experiments, both CTW and CTE showed high effects, and as a result of analyzing the total phenol and flavonoid contents, both CTW and CTE showed high contents. Based on the results of the experiment, the Cheongtaejeon tea extract is expected to have a highly valuable as a functional cosmetics material related to antioxidants.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.267-273
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• 2008

Water-soluble fraction (WSF) from edible mushroom hinmogi (Tremella fuciformis) were obtained by water extraction, and polysaccharides in the WSF were separated by ethanol precipitation. The inhibitory effects of the polysaccharides on 3T3-L1 adipocyte differentiation were evaluated by the reduction of peroxisome proliferators-activated receptor ${\gamma}$ ($PPAR{\gamma}$) translation, triglyceride accumulation, Oil Red-O staining, and expression levels of $PPAR{\gamma}$, CCAAT/enhancer binding protein a (C/$EBP{\alpha}$), and leptin. The $PPAR{\gamma}$ translation in 3T3-L1 cells was inhibited by the treatment with polysaccharide precipitated by 80% ethanol (P80) which showed highest inhibitory activity among polysaccharides tested. In addition, treatment of P80 to 3T3-L1 cells significantly inhibited the triglyceride accumulation, Oil Red-O staining, and mRNA expression of $PPAR{\gamma}$, C/$EBP{\alpha}$, and leptin in a dose-dependent manner. Based upon these results, P80 from edible mushroom hinmogi shows the inhibitory activity on the differentiation of 3T3-L1 adipocytes. Therefore, it might be employed as a potential anti-obesity material.