• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.458-463
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• 2011

The effect of subcritical water for the extraction of total polyphenols and flavonoids from apple peel was investigated, and then the antioxidant activity of the extracts was estimated. Maximum yields of total polyphenolic compounds($36.4{\pm}1.9mg$ quercetin equivalent(QE)/g dried material) and flavonoids($9.9{\pm}0.8mg$ QE/g dried material) were obtained by subcritical water extraction(SWE) with operating conditions of $190^{\circ}C$, 1,300 psi, and 20 min. Furthermore, the highest antioxidant activity($76.1{\pm}1.1%$) was observed in the extract obtained from SWE using the same conditions. The flavonoids from the SWE of apple peel were compared to three conventional extraction methods in terms of their extraction efficiency and antioxidant activity. The SWE was significantly more effective than hot water ($90^{\circ}C$), methanol, and ethanol extraction for flavonoid yield by 4.7-, 2.2-, and 1.3-fold, respectively, and for antioxidant activity by 11.0-, 4.9, and 2.8-fold, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.585-590
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• 2002

The effects of a high level of sucrose on the moisture content, water activity, protein denaturation and sensory properties in Chinese-style pork jerky were investigated. The pork jerky with different levels (0, 12, 15, 18 and 21%) of sucrose was prepared. Fifteen frozen boneless pork legs from different animals were used in this trial. Sucrose is a non-reducing disaccharides and would not undergo non-enzymatic browning. Some studies pointed out that sucrose might be hydrolyzed during freezing, dehydration and storage into glucose and fructose, and cause non-enzymatic browning in meat products. The results showed that moisture content and water activity of pork jerky decreased with increase of the level of sucrose. At the same time, shear value was increased due to the reduced moisture content and water activity by osmotic dehydration. However, a higher level of sucrose had a significantly negative effect on protein solubility and extractability of myosin heavy chain of pork jerky due to non-enzymatic browning. From the results of sensory panel tests, the pork jerky with 21% of sucrose seems to be more acceptable by the panelists in hardness, sweetness and overall acceptability.

• Food Engineering Progress
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• v.14 no.4
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• pp.342-345
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• 2010

The purpose of current study was to examine bioaccessibility of antioxidant activity and total phenolic content in each part of water spinach (Ipomoea aquatic Forsk.). In vitro biomimicking system simulated human digestive fluid was employed in order to measure bioavailable anti-oxidative effect and phenolic content. Antioxidant activity and total phenolic content was measured by using the DPPH method and the Folin-Ciocalteu assay, respectively. Stem of water spinach had a higher DPPH free radical scavenging effect (5.43 mg/mL for $IC_{50}$) than leaf (5.95 mg/mL for $IC_{50}$), while leaf had a greater level of total phenolic content (287.45 ${\mu}g$ GAE/mL) than stem (216.45 ${\mu}g$ GAE/mL). Bioaccessible antioxidant capacity and digestive stability of total phenolic content showed a similar pattern to what found in raw materials. Our result also indicated that total phenolic content was not found to be a major marker for prediction of antioxidant activity. It is plausible that other constituents such as vitamin E and C in water spinach could be contributors for antioxidant activities.

• 한국해양학회지
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• v.5 no.1
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• pp.1-5
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• 1970

The hydration numbers of some salts present in sea water have been calculated by a simple model for the equation of the dielectric constant, and the mean activity coefficients from the theoretical formula proposed by Jhon and Eyring. The validity of the theory for the electrolyte solution is tested by evaluating the hydration numbers and the mean activity coefficients of some 1:1, 1:2, 2:1 and 1:3 electrolytes in sea water. The results show good agreement with the observations.

• Journal of Microbiology and Biotechnology
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• v.8 no.3
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• pp.191-196
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• 1998

This mini review describes the effects of water activity (${\alpha}_w$) on the kinetics, regio- and enantioselectivities of lipases, and various methods for measuring and controlling ${\alpha}_w$ in lipase catalyzed reaction in organic solvent.

• Korean Journal of Pharmacognosy
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• v.41 no.2
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• pp.130-135
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• 2010

This study was performed to the activity of antioxidant and anti-diabetic from Zanthoxylum schnifolium fruit. The Zanthoxylum schnifolium fruits were extracted with water, 100% methanol, 100% ethanol, 70% methanol and 70% ethanol. The activities of each extracts were measured by antioxidant tests, such as total phenolic contents, total flavonoid contents, hydroxyl radical activity, DPPH radical scavenging activity, reducing power and $\alpha$-glucosidase inhibition activity assay. The water extract represented the highest activity in the antioxidants properties in vitro, including hydroxyl radical activity, DPPH radical scavenging activity, reducing power. Furthermore, water extract also showed significantly high total phenolic contents but the 100% methanol extract showed high total flavonoid contents estimated as $196.48{\mu}g/mg$. The $IC_{50}$ values for $\alpha$-glucosidase inhibition activity of the 100% ethanol and 100% methanol extracts were $275.66{\mu}g/mg$ and $261.44{\mu}g/mg$. Our results indicated that the Zanthoxylum schnifolium fruit expected to be useful as antioxidants.

• The Korean Journal of Community Living Science
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• v.19 no.1
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• pp.3-10
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• 2008

This study was conducted to gather basic data on the physiological activities of flower extracts from 4 cultivars of white lotus to promote the increase of public consumption. Four cultivars of white lotus: c.v. 'Garam', 'Choeue', 'Baekhwageonryeon', and 'Seungdal' were harvested on 14, August, 2007, and the physiological activities of flower extracts obtained by hot water extraction and ethanol extraction were examined. Total phenol content was highest in the 'Garam' flower hot water extracts, $144.2{\mu}g{\cdot}mL^{-1}$, and lowest in the 'Seungdal' flower ethanol extracts, $63.4{\mu}g{\cdot}mL^{-1}$. DPPH radical scavenging activity was highest at 2,000ppm flower extract of 'Garam' obtained by hot water extraction and ethanol extraction of 90.9% and 83.0%, respectively. Total flavonoid content in the flower extracts of 'Garam' obtained by hot water extraction and ethanol extraction showed the highest levels at $34.1{\mu}g{\cdot}mL^{-1}\;and\;33.9^{\mu}g{\cdot}mL^{-1}$, respectively. Nitrite scavenging activity at 1,000ppm flower extract was highest in 'Garam'. Extracts obtain by hot water and ethanol showed 91.3% and 80.4% activity, respectively. No significant difference in tyrosinase inhibition activity was observed among the cultivars or as a result of extraction method. Overall anti-microbial activity of the flower extracts was slightly higher in 'Garam' than in the other cultivars.

• The Korea Journal of Herbology
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• v.21 no.4
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• pp.103-107
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• 2006

Objectives : This study was investigated to analyze the anti-oxidant activity of water and ethanol extracts from the Magnoliae Flos. Methods : The effects on electron donating ability (EDA), SOD-like activity and xanthine oxidase inhibition have been investigated the anti-oxidant activity for utilization as a natural material of cosmetics. Results : This study was investigated to analyze the anti-oxidant activity of water and ethanol extracts from the Magnoliae Flos. In the electron donating ability test, water and ethanol extract from Magnoliae Flos showed an effect of 75.6% and 83.5% at 1,000 ppm concentration, respectively. In the superoxide dismutase (SOD)-like activity, 1,000 ppm of water extract showed an effect of 45.2% and ethanol extract showed an effect of 64.2%. Xanthine oxidase showed a meaningful inhibitory effect of 68.8% in water extract and 23.2% at 1,000 ppm in ethanol extract. Conclusion : From these results, Magnoliae Flos showed the development possibility as a natural material of anti-oxidant cosmetics.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5207-5212
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• 2013

Background: Physical activity has been found to play a role in cancer prevention. The purpose of this matched case-control study was to investigate the association between physical activity levels, water intake, constipation and colorectal cancer (CRC). Materials and Methods: Two hundred and thirty-two patients diagnosed with CRC (125 male, 107 female) were enrolled in this case-control study. Cases were matched to 271 population controls (137 male, 134 female). Results: Drinking more than 4 cups of water daily decreased the risk of CRC by 33-42%; however, this effect was non-significant. Having constipation was found to be a significant risk factor for developing CRC with an OR=6.284 (95%CI=2.741-14.40). With reference to sedentary behavior, minimum activity (600-3000 Metabolic Equivalents Task (MET)) had 43% protection against CRC and the level of Health Enhancing Physical Activity OR was 0.58 (at 95%CI; 0.37-0.92). A significant negative association was found between CRC and physical activity levels expressed as both METs and MET-hours/week (p for trend=0.017 and 0.03, respectively). Among females, a significant trend of reduction in CRC by 62% was observed with increasing the level of physical activity expressed in MET (p for trend=0.04). Conclusions: The risk of CRC may be reduced by adopting a healthy lifestyle and practicing physically activity regularly, especially among females. Consuming adequate amounts of water and healthy bowel motility could also reduce the risk of CRC.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.330-335
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• 1991

The values of water activity in the different concentrations of NaCl and sodium lactate were measured by hygrometer in the water-sorbitol systems. Interaction of NaCl and sodium lactate was evaluated by Raoult's law. The discrepancy between experimental and theoretical value by the Raoult's law was defined as interaction between water-sorbitol and added solutes in the systems. The changes of interacted water and solutes were observed in whole range of water activity. The value of interacted water (water: sorbitol=1 : 1.1241) obtained by added sodium lactate was found to be higher than sodium chloride. The amount of interacted solute reached maximum about Aw 0.87, while the interactions between added solute and sorbitol showed an increasing tendency below Aw 0.87.