• Biomolecules & Therapeutics
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• v.15 no.4
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• pp.205-211
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• 2007

The fruits and stems of Opuntia ficus-indica var. saboten have been reported to exhibit a variety of pharmacological actions, including antioxidant, analgesic, anti-inflammatory, and anti-ulcer effects. In the present study, we evaluated effects of the butanol fraction (SK OFB901) prepared from the 50% ethanol extract of the stems on various types of neuronal injuries induced by oxidative stress, excitotoxins, and amyloid ${\beta}\;(A_{\beta})$ in primary cultured rat cortical cells. Its antioxidant and radical scavenging activities were also evaluated by cell-free bioassays. We found that SK OFB901 strongly inhibited the oxidative neuronal damage induced by $H_2O_2$ or xanthine/xanthine oxidase. In addition, it exhibited marked inhibition of the excitotoxic neuronal damage induced by glutamate, N-methyl-D-aspartic acid, or kainate. Furthermore, the $A_{\beta(25-35)}$-induced neurotoxicity was also significantly attenuated by SK OFB901. It was found to inhibit lipid peroxidation initiated by $Fe^{2+}$ and L-ascorbic acid in rat brain homogenates and scavenge 1,1-diphenyl-2-picrylhydrazyl free radicals. These results indicate that the butanol fraction prepared from the stems of Opuntia ficus-indica var. saboten exerts potent antioxidant and neuroprotective effects through multiple mechanisms, implying its potential applications for the prevention or management of neurodegenerative disorders associated with oxidative stress, excitotoxicity, and $A{\beta}$.

• Journal of Society of Preventive Korean Medicine
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• v.1 no.1
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• pp.48-54
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• 1997

Scutellariae radix, has been used as a natural drug for fever, inflammation, cataract, and liver disease in traditional medicine. This study was performed in order to investigate the antioxidative effects of Scutellariae radix aqua-acupuncture solution (SRAS) on lipid peroxidation by free radicals. Lipid peroxidation levels were determined by TBA method during the autoxidation of linoleic acid. In this linoleic acid autoxidation system, SRAS markedly exhibited antioxidant activity, which inhibited 89% of linoleic acid peroxidation. SRAS showed scavenging effects on ${\alpha},{\alpha}-diphenyl-{\beta}-picrylhydrazyl$(DPPH) radical, inhibited superoxide generation in xanthine-xathine oxidase system, and also inhibited lipid peroxidation of rat liver tissue by hydroxyl radical derived from $H_2O_2-FE^{+2}$ system. These effects were similar to those of $dl-{\alpha}-tocopherol$, BHA and BHT. In addition, SRAS protected the cell death induced by ter-butyl hydroperoxide (t-BHP) and significantly increased cell viability in the normal rat liver cell (Ac2F). On the basis of these results, it is suggested that SRAS might play a protective role in lipid peroxidation by free radicals.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.141-147
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• 2012

Biogenic amines have been used as chemical indicators to estimate bacterial spoilage of foods, particularly fish and fish products, cheese, and fermented foods. So far many chromatography methods have been developed to detect biogenic amines in foods. Although these instrumental analyses exhibit good sensitivity, they cannot be used as rapid detection methods due to the chemical treatment of the samples and the time-consuming process involved. For the rapid and simple detection of biogenic amines, enzyme linked immunosorbent assay kits are commercially available. In addition, analytical systems with enzyme-based amperometric biosensor detection have been increasingly developed. The biosensors used to detect the biogenic amines are based on the action of either amine oxidases or amine dehydrogenases that catalyzes the oxidative deamination of biogenic amines to the corresponding aldehydes and ammonia. This review mainly focused on the principle, development, and applications of the detection methods for rapid detection of biogenic amines in foods.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.133-137
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• 2015

The Galactic center uniquely provides opportunities to resolve how star clusters form in neutral gas overdensities engulfed in a large-scale accretion flow. We have performed sensitive Green Bank 100m Telescope (GBT), Karl G. Jansky Very Large Array (JVLA), and Submillimeter Array (SMA) mapping observations of molecular gas and thermal dust emission surrounding the Galaxy's supermassive black hole (SMBH) Sgr $A^{\ast}$. We resolved several molecular gas streams orbiting the center on ${\gtrsim}10$ pc scales. Some of these gas streams appear connected to the well-known 2-4 pc scale molecular circumnuclear disk (CND). The CND may be the tidally trapped inner part of the large-scale accretion flow, which incorporates inflow via exterior gas filaments/arms, and ultimately feeds gas toward Sgr $A^{\ast}$. Our high resolution GBT+JVLA $NH_3$ images and SMA+JCMT 0.86 mm dust continuum image consistently reveal abundant dense molecular clumps in this region. These gas clumps are characterized by ${\gtrsim}100$ times higher virial masses than the derived molecular gas masses based on 0.86 mm dust continuum emission. In addition, Class I $CH_3OH$ masers and some $H_2O$ masers are observed to be well associated with the dense clumps. We propose that the resolved gas clumps may be pressurized gas reservoirs for feeding the formation of 1-10 solar-mass stars. These sources may be the most promising candidates for ALMA to probe the process of high-mass star-formation in the Galactic center.

• Korean Journal of Weed Science
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• v.16 no.2
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• pp.100-107
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• 1996

Pre- and post-emergent control of Aneilema keisak was investigated in no-till paddy fields. In addition, a pot trial was conducted to determine use rates of the experimental post-emergent herbicide LGC40863. For pre-emergent control, butachlor(1,800g ai/ha), pretilachlor(600g ai/ha), pretilachlor plus pyrazosulfuron(300+18g ai/ha, respectively), thiobencarb plus bensulfuron(2,100+51g ai/ha, respectively), and molinate plus pyrazosulfuron(1,500+21g ai/ha, repectively) were treated at 20 days before seeding. Among the herbicides, molinate plus pyrazosulfuron was the least effective (23% control), while all other herbicides provided excellent(>95%) control of A. keisak. None of these herbicides caused rice phytotoxicity. However, rice yield in the plot treated with molinate plus pyrazosulfuron decreased about 50% due to poor A. keisak control. LGC40863 controlled A. keisak completely, by foliar application, across wide growth stages from the 5- to 15-leaf at 50g ai/ha in pot tests. In the field, treatment of LGC40863(30 to 50g ai/ha) provided >95% control of A. keisak when treated either at 15 days after transplanting or at non-productive tillering stage. Efficacy of 2,4-D and bentazon was insufficient when treated at non-productive tillering stage. These results suggest that, in no-till paddy fields, A. keisak is controlled by pre-emergent application of butachlor, pretilachlor, pretilachlor plus pyrazosulfuron, or thiobencarb plus bensulfuron, and by post-emergent application of LGC40863.

• Korean Journal of Materials Research
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• v.10 no.3
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• pp.246-252
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• 2000

Thermoelectric properties of the $Bi_2(Te_{0.85}Se_{0.15})_3$ alloy, prepared by mechanical alloying and hot pressing, were investigated with the variation of the hot-pressing temperature ranging from $300^{\circ}C$ to $550^{\circ}C$. Contrary to the p-type behavior of single crystal, the hot-pressed $Bi_2(Te_{0.85}Se_{0.15})_3$ alloy exhibited n-type conduction without addition of donor dopant. When the $Bi_2(Te_{0.85}Se_{0.15})_3$ powders were annealed in $(50{\%}\;H_2+50{\%}\;Ar)$ atmosphere, the hot-pressed specimens exhibited a positive Seebeck coefficient due to the reduction of the electron concentration by removal of the oxide layer on the powder surface and annealing-out of the excess Te vacancies. Figure-of-merit of the hot-pressed $Bi_2(Te_{0.85}Se_{0.15})_3$ alloy was improved by hot pressing at temperatures above $450^{\circ}C$, and the maximum value of $1.92{\times}10^{-3}/K$ was obtained for the specimen hot-pressed at $550^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.237-245
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• 2004

The physicochemical and physiological activities of domestic garlic from 3 different areas (Namhae, Jeju and Uiseong) were analyzed. The contents of moisture, ash, crude protein and crude fiber in garlic were little different in 3 kinds of area. Total sugar and water soluble phenolic compounds were higher in garlic from Namhae. The free sugars found in garlic were fructose, sucrose and lactose. Five kinds of organic acids were determined. Malonic acid and citric acid contents in garlic from Namhae were 23.7${\pm}$1.16 mg% and 22.1${\pm}$0.82 mg%, respectively. Total mineral content of garlic samples were in a range of 7112.6～9067.3 mg%, the potassium content showed the highest concentration (4117.3${\pm}$7.19～5175.3${\pm}$9.61 mg%). The electron donating abilities in 0.2% of garlic from Namhae and Uiseong showed 46.2${\pm}$1.25% and 37.0${\pm}$1.l6%, respectively. The nitrite scavenging effect was measured at different conditions (pH 1.2 and 4.2). The nitrite scavenging effects were higher at pH 1.2, and reached more than 95% by adding 0.2% and 0.1 % of garlic juice at pH 1.2. Addition 0.02～0.001 % garlic juice in showed the SOD-like activities. Its activity of garlic from Namhae. was a range of 6.0${\pm}$0.37～14.4～0.69%. It was found that 0.2% and 0.1% garlic showed strong antimicrobial action against growth of all the tested bacteria. Antimicrobial action. was showed 74.7${\pm}$0.70% and 51.7${\pm}$1.l1% on Sal. typhimurium in 0.2% of garlic from Namhae and Uiseong and 28.6${\pm}$0.90% on B. subtilis in garlic from Jeju.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.642-647
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• 2006

Yeast selection and the sterilization methods of strawberry juice were optimized for making strawberry wine. In addition, changes in the physicochemical characteristics of the wine during its fermentation were estimated. Maehyang and Yukbo cultivars of strawberry were tested for wine making; they contained 9.8 and 9.3% soluble solids and 0.59 and 0.58% titratable acidities, respectively. Among six yeasts tested, the Wg-15 and Sc-51 strains were selected based on the alcohol yield in the strawberry wine. Alcohol and soluble solid contents following heat treatment ($85^{\circ}C$, 10 min) or $K_2S_2O_5$ (200 ppm) treatment for sterilization were 7.10-7.20% and 5.60-5.80%, respectively, and no differences were observed between the Wg-15 and the Sc-51 strains. However, the flavor of wine produced following heat treatment was slightly better than that following $K_2S_2O_5$ treatment. The greatest amounts of alcohol were produced after 2 days of fermentation at $26^{\circ}C$. The alcohol content in wines produced with 12, 14, and 16% sugar content in the initial stages were 5.1, 6.0-6.2, and 7.5-7.7%, and the soluble solid contents were 3.9-4.3, 4.1-4.3, and 5.0-5.3%, respectively; no significant differences were observed between the Wg-15 and the Sc-51 yeast strains. For making strawberry wine, we proposed that the sugar content of Maehyang or Yukbo cultivars be adjusted to 16% soluble solids in the initial stages with heat treated at $85^{\circ}C$ for 10 min and fermentation with the Wg-15 or Sc-51 yeast strains at $26^{\circ}C$ for 8 days.

• Food Science and Preservation
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• v.23 no.5
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• pp.680-688
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• 2016

This study analyzed the changes in physicochemical components of Astragalus membranaceus (AM) fermented with Phellinus linteus. Moisture content, pH, total acidity, total reducing sugar content, extraction yield, free sugar content, free amino acid and isoflavonoid (calycosin, formononetin) were investigated. The moisture content was increased during fermentation with Phellinus linteus. The pH level increased while the total acidity significantly decreased during fermentation. The reducing sugar content were in the range of 0.32~0.61%. The extraction yield using water was higher than that using 80% ethanol. The major free sugars were identified as glucose, fructose, sucrose and the content of free sugars decreased through fermentation. However, the glucose and sucrose contents of the water extracts were increased. In addition, the free amino acid increased significantly during fermentation. Finally, calycosin and formononetins contents in water extracts of after 30 days of AM fermentaion with Phellinus linteus were (3.91 mg/100 g) and (1.38 mg/100 g), respectively. These results suggest that fermentation with Phellinus linteus could be used to increase the bioactivity of AM. The mycelium-fermented AM could be a valuable source of functional material and edible resource for industry.

• Applied Biological Chemistry
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• v.28 no.1
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• pp.28-35
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• 1985

Potato tubers treated at $4^{\circ}C$ for 4 weeks were irradiated with a dose of 0.12 kGy from $^{60}Co$ source and stored at $20^{\circ}C,\;70{\sim}90%$ humidity for 5 weeks. Changes of ${\alpha}-amylase$, peroxidase, indole acetic acid oxidase, indole acetic acid synthesizing enzyme activities were determined. In addition, treatment of gibberellin or indole acetic acid to tubers irradiated were carried out to examine reversal of sprout-inhibition of tubers irradiated. Results are as follows; 1. Irradiation by ${\gamma}-ray$ at 0. 12 kGy dose inactivated easily the enzyme activities in vitro. $D_{37}$ values obtained were 0.94, 0.36 kGy for ${\alpha}-amylase$ and peroxidase, respectively 2. Complete inhibition of the toter sprouting was resulted by the irradiation of tubers with a dose of 0.12 kGy. 3. The indole acetic acid oxidase activity increased 2 times immediately after irradiation. Meanwhile, indole acetic acid synthesizing activity decreased about $50{\sim}75%$ for 5-week storage in irradiated potatoes, whereas the activity increased about 3.5 times along with sprouting in non-irradiated tubers. 4. In morphological aspects, deformed buds with necrosis in the meristmatic tissue were developed in irradiated tubers. Treatment of gibberellin or indole acetic acid at the concentration of 100 or 20 ppm to the irradiated tubers reversed the sprout-inhibition partially. Nevertheless, the deformed buds remained without change.