• Journal of Ginseng Research
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• v.45 no.6
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• pp.665-675
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• 2021

Background: Ginsenoside Rg1 (Rg1), an active ingredient in ginseng, may be a potential agent for the treatment of Alzheimer's disease (AD). However, the protective effect of Rg1 on neurodegeneration in AD and its mechanism of action are still incompletely understood. Methods: Wild type (WT) and APP/PS1 AD mice, from 6 to 9 months old, were used in the experiment. The open field test (OFT) and Morris water maze (MWM) were used to detect behavioral changes. Neuronal damage was assessed by hematoxylin and eosin (H&E) and Nissl staining. Immunofluorescence, western blotting, and quantitative real-time polymerase chain reaction (q-PCR) were used to examine postsynaptic density 95 (PSD95) expression, amyloid beta (Aβ) deposition, Tau and phosphorylated Tau (p-Tau) expression, reactive oxygen species (ROS) production, and NAPDH oxidase 2 (NOX2) expression. Results: Rg1 treatment for 12 weeks significantly ameliorated cognitive impairments and neuronal damage and decreased the p-Tau level, amyloid precursor protein (APP) expression, and Aβ generation in APP/PS1 mice. Meanwhile, Rg1 treatment significantly decreased the ROS level and NOX2 expression in the hippocampus and cortex of APP/PS1 mice. Conclusions: Rg1 alleviates cognitive impairments, neuronal damage, and reduce Aβ deposition by inhibiting NOX2 activation in APP/PS1 mice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.68-78
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• 1997

Laboratory and greenhouse studies were conducted to determine differential sensitivities on absorption of $^{14}$ C-oxyfluorfen and the anatomical responses in wheat and barley to protoporphyrinogen oxidase-inhibiting herbicides [oxyfluorfen (2-chloro-1- (3-ethoxy -nitrophen-oxy)-4-(trifluoromethyl) benzene, acifluorfen(5-[2-chloro-4-(trifluoromethyl) phenoxy]-2-nitro-benzoic acid), bifenox(methyl-5-(2, 4-dichlorophenoxy)-2-nitrobenzoate) and oxadiazon(5-tert-butyl-3-(2, 4-dichloro-5-isopropoxyphenyl)-1, 3, 4-oxadiazol-2-one)]. I$_{50}$ value of the tolerant wheat cultivars to oxyfluorfen was about 10$^{-4}$ , whereas that of the susceptible barley cultivars was about 10$^{-6}$ M, showing significant difference between the two groups. When foliage were applied with acifluorfen, bifenox or oxadiazon, the oxyfluorfen-tolerant wheat showed less decreased in shoot fresh weight and chlorophyll content than the susceptible barley. Also, when soil-applied with these herbicides test plants showed similar tendency in foliar application. Electrolyte leakage from the tissue treated with these compounds was the more influenced in the barley than the wheat. Malondialdehyde(MDA) production as index of lipid peroxidation was greater in the barley than the wheat by treatment of these compounds. Therefore, the differential sensitivities of wheat and barley to protoporphyrinogen oxidaseinhibiting herbicides was showed by our greenhouse and in vitro experiment. The absorption rates of $^{14}$ C-oxyfluorfen were higher in the barley than the wheat. And this tendency was showed appararitly difference by increase of treatment durations. After the oxfluorfen and oxadiazon treatment, the tolerant wheat did not show the structural damage in leaf surface, but the susceptible barley was damaged in the leaf waxy layer. However, the acifluorfen and bifenox treatment showed no difference between wheat and barley. The anatomical changes by these compounds treatment were not observed in the tolerant wheat but epidermal cell and mesophyll cell were highly broken in the susceptible barley.

• Biomolecules & Therapeutics
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• v.17 no.4
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• pp.412-417
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• 2009

In the course of screening for antioxidant compounds by measuring the radical scavenging effect on DPPH (1,1-diphenyl- 2-picrylhydrazyl), a total extract of the twigs of Vitex rotundifolia (Verbenaceae) was found to show potent antioxidant activity. Subsequent activity-guided fractionation of the methanolic extract led to the isolation of three iridoid compounds, 10-O-vanilloylaucubin (1), 10-O-p-hydroxybenzoylaucubin (2) and aucubin (3), two C-glycoside flavones, vitexin (4) and orientin (5), and a quinic acid derivative, 3,4-di-O-caffeoylquinic acid (6). Their structures were elucidated by spectroscopic studies. Among them, compounds 5 and 6 showed the significant antioxidative effects on DPPH free radical scavenging test. In riboflavin-NBT-light and xanthine-NBT-xanthine oxidase systems, compounds 5 and 6 exhibited the formation of the blue formazan in a dose-dependent manner. Compounds 5 and 6 showed better superoxide quenching activities than vitamin C.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1145-1150
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• 2000

면역증강물질을 생산하는 균주를 해수로부터 분리하여 동정한 결과 크림색의 둥근 점질성의 집략을 나타내었으며, Gram 음성의 간산형이고, 미약한 운동성을 가지며 catalase 양성과 oxidase 음성 반응을 보였다. 균주를 6시간 , 20시간, 72시간, 및 144시간 뱅양하여 전자 현미경사에서 관찰한 결과 20시간 배양한 영양세포는 1.25~0.6$\times$0.6$\mu\textrm{m}$ 크기의 간균 형태를 갖추었으며 시간이 흐를수록 세포내 관립의 밀도가 증가하면서 세포형태가 다형태성으로 변하였다. 세포내 과립의 존재를 확인하기 위해 sudan black B로 염색한 결과 양성으로 polyhy-droxy butyrate로 예상되었다. 생육을 위한 최적 온도는 3$0^{\circ}C$, pH는 3.0~10.0이었으며, 호기성균이었다. D-Glu-cose, D-mannose, D-mannitiol. insitol, maltose 등의 당과 L-asparagine, L-glutamate 등의 아미노산을 이용하였고 특시, O/F test에서 glucose와 maltose를 산화 하였다. 이상과 같은 결과로 해양세균 유래인 Pseudo-mallei group의 Burkholderia 속으로 확인되었음로 본 균주를 Burkholderia sp. IS-203으로 명명하였다.

• Korean Journal of Veterinary Service
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• v.30 no.1
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• pp.77-84
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• 2007

The present study was carried out to investigate the incidence of Campylobacter spp. from the chicken carcasses in slaughterhouse. A total of 9 strains were primarily isolated from enrichment culture and selective culture of the sample with candle and microaerophilic chamber method. Nine of Gram-negative, catalase-positive and oxidase-positive strains were further isolated by the determination of biochemical characteristics and finally identified as Campylobacter jejuni with HIP 400F and HIP l134R primers. Therefore, this PCR method proved to be useful as a routine diagnostic test for the Campylobacter detection and confirmation of C. jejuni and C. coli in naturally contaminated poultry samples.

• Journal of Applied Biological Chemistry
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• v.43 no.2
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• pp.74-78
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• 2000

A strain that produces a high level of carboxymethyl cellulase was isolated from rotten leaves. The isolated strain was revealed to be gram-negative, oxidase-positive, and catalase-negative. From the electron microscopic features, it was identified as a rod-shaped bacterium with peritrichous flagella and did not form spores. Morphological and biochemical characteristics of the strain were found to be similar to the Pseudomonas species. However, carbon utilization test showed different results. Based on the results, this new strain was identified as Pseudomonas sp. CMC-50. CMCase produced by this strain showed a strong activity in neutral and weak acidic conditions and maximum activity at $50^{\circ}C$.

• Environmental Analysis Health and Toxicology
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• v.12 no.3_4
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• pp.1-13
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• 1997

First- and second-order kinetic oxidation rates of trichlorobenzenes (TCBs) were obtained and compared by a chemical activation system (CAS) which mimics mixed functional oxidase activity. The system consists of EDTA, ferrous sulfate, ascorbic acid, and $H_2O_2$ in potassium phosphdte buffer (monobasic at pH 7.4). The rate of transformation in CAS was enhanced in the presence and absence of catalase in the sequence 1, 2, 3-TCB < 1, 2, 4-TCB < 1, 3, 5-TCB. In general, the rates of degradation were greater in the test media with catalase. The effect of photolysis on the degradation of the TCBs with the CAS were examined. Sensitized photolysis with nitrite, Fenton's reagent, TiO$_2$ and triethylamine (TEA) studied in concert with the CAS demonstrated significant enhancement of the degradation rate of TCBs. Disappearance rates of TCBs in CAS with prior photolysis or prior photosensitization were at least 10-fold higher than the sum of the rate for each single experiment. This study proves that the combination of the CAS and photolysis can be used as a suitable technique for enhancing degradation of TCBs in aqueous systems.

• Journal of Nutrition and Health
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• v.26 no.6
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• pp.680-691
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• 1993

Rats were fed for an 8-week period a low riboflavin diet(5ug riboflavin/day) or a control diet(30ug/day) supplied either ad libitum or by pair feeding in order to study the effect of riboflavin on the metabolism of lipids and neurotransmitters. Erythrocyte glutathione reductase (EGR) and monomine oxidase(MAO) activity in the liver and brain were assayed. EGR activity coefficient in riboflavin deficient rats was significantly higher than in ad libitum controls whereas MAO activity was decreased in the deficient rats. Fatty acid composition showed a different trend in the serum, liver and brain. In the serum, the concentrations of essential fatty acids and $\omega$-3 fatty acids(eicosapentaenoic acid, docosahexaenoic acid)were decreased about 20-40% in the deficient and pair-fed than in the ad libitum controls. Brain serotonin and 5-HIAA(5-hydroxyindole acetic acid) concentrations were decreased in the riboflavin deficient rats. Learning ability measured by a water maze and exploratory activity using the open field test were not impaired in the deficient rats. These results indicate that brain lipid metabolism was protected in subclinical riboflavin deficiency, however, riboflavin deficiency affected brain serotonin content.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.98.2-99
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• 2003

Bacterial canker of sweet cherry (Prunus cerasus L.) was observed in farmers' orchard in Goesan, Chungbuk in 2003. Typical canker symptom occurred on the branches or twigs of sweet cherry in early spring and bacterial exudates oozed out of the cracked barks of diseased trees. Watersoaked brown symptom appeared on the leaves and severe infection caused thorough defoliation on the branches or twigs of sweet cherry. When cut the severely infected branches or twigs, irregular and rusty-colored symptoms in sapwood and heartwood were clearly found, indicating that they could serve as specific symptoms of bacterial canker of sweet cherry. The gram negative, aerobic bacterium isolated from the lesion produced fluorescent pigments on King's B agar medium but did not grow at 37$^{\circ}C$ The bacterium formed Levan-type colonies, and showed negative reactions in oxidase reaction, arginine dihydrolysis test, and pectolytic activity Based on the biochemical and pathological characteristics, the causal organism was identified as Pseudomonas syringae pv. morsprunorum. This is the first report on bacterial canker of sweet cherry in Korea.

• The Plant Pathology Journal
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• v.18 no.1
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• pp.23-29
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• 2002

A total of 672 Cryphonectria parasitica was isolated from 2,536 blight lesions on chestnut twigs, which were collected from major chestnut plantations all over Korea. Isolation rates of each province ranged from 13.5% in Jeonbuk-ds to 37.4% in Gyeongnam-do, with an average rate of 25.6%. The isolates were classified into six groups according to color and shape of colony on PDA: smooth margin (S), irregular margin (I), yellow to brown (Y), white (W), and white with yellow center (C). Among these groups, IY was the most abundant with an isolation rate of 65%. On the other hand, SW, SC, IW, and SY were quite rare, with isolation rates ranging from 1.5% to 5.8%. When the 672 isolates were inoculated on the chestnut twigs,380 isolates (56.5%) caused lesions larger than the standard virulent isolate EPISS-2, while 158 isolates (23.4%) caused smaller lesions than the standard hypovirulent isolate UEP-1. However, 87.4% of the isolates belonged to the virulent group and only 12.6% belonged to the hypovirulent group based on Bavendamm test. In the provinces of Jeonnam-do, Jeonbuk-do, and Gyeongnamdo, which have high density of chestnut trees, the rates of hypovirulent-like isolates were over 20%.