• Journal of Environmental Health Sciences
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• v.33 no.1 s.94
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• pp.21-29
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• 2007

Paeonia lactiflora was stepwise extracted with hexane, chloroform, ethyl acetate, butanol and water. Anti-microbial activity of each extract was investigated. Methanol extract of P. lactiflora revealed anti-microbial activity against S. mutans, C. albicans, and S. aureus. Also, hexane fraction revealed anti-bacterial activity against S. mutans and ethyl acetate fraction acted as potent anti-microbial agent on C. albicans and S. aureus. The relative growth ratio(RGR) of hexane fraction of P. lactiflora against S. mutans were determined as 77.8% in concentration of 0.125 mg/ml, 98.46% in 0.25 mg/ml and 100% in 0.5 mg/ml. The ethyl acetate fraction of P. lactiflora revealed RGR against C. albicans as 52.5% in concentration of 0.125 mg/ml, 60.83% in 0.25 mg/ml and 78.33% in 0.5 mg/ml. It indicate that increasing concentration increase RGR. The measured minimal inhibitory concentration(MIC) of hexane fraction on S. mutans KCTC 5316 strain was 0.5 mg/ml and MIC of ethyl acetate fraction on C. albicans KCTC 7270 was 2.0 mg/ml. The experiment of inhibition to growth of KB roll(oral squamous cell carcinoma) result 61.9% in butanol, 76.7% in hexane extract of P. lactiflora. The hexane extract exhibit potent inhibition effect to the growth of KB cell. These results suggest that the hexane extract of Paeonia lactiflora has antimicrobial activity against S. mutans and has preventive effect to dental caries in addition to potent inhibition to KB cell growth.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.621-625
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• 2004

Electron donating abilities, nitrite scavenging effects and antimicrobial activities of various fractions obtained from ethanol extract of Smilax china were examined. Among the fractions investigated, the highest electron donating ability was determined with ethyl acetate fraction showing about 81.0% when reacted for 10 min. However, the lowest ability was found from chloroform fraction. Ethyl acetate and butanol fractions also showed very high nitrite scavenging activity at all concentrations tested. All the fractions revealed antimicrobial activity against Listeria monocytogenes and Staphylococcus aureus, Gram (+) bacteria, at both 2.5% and 5.0% concentrations. However, no antimicrobial activity was observed on Escherichia coli O157:H7 and Salmonella Typhimurium, Gram (-) bacteria, at 2.5%, but very low activity was detected by 5.0% concentration of ethanol extract, ethyl acetate and water fractions.

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.179-185
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• 2007

Esterase isozymes were investigated from digestive juice of M. saltuarius adults after pesticide treatment. Twelve esterase isozymes were separated on 12% native-PAGE gel and stained with three different substrates(${\alpha}$-naphthyl acetate, ${\beta}$-naphthyl acetate, and ${\alpha}$-naphthyl butyrate). Interestingly, the isozyme of Est1(${\alpha}$-naphthyl acetate) was strongly inhibited by the carbofuran and methomyl. The Est1 activity was completely inhibited by the chlorpyrifos and partially inhibited by methidation about 70 %. In addition, eserine suppressed esterase isozyme activities of Est1 about 70% and isozyme activities of Est2, Est3, and Est4 were weakly inhibited. ${\alpha}$-pinene did not suppressed esterase isozyme activities but activities of esterases were very weakly inhibited in camphor and bornyl acetate.

• Microbiology and Biotechnology Letters
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• v.47 no.1
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• pp.54-63
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• 2019

Rubus coreanus Miquel (RCM), also known as Korean blackberry or bokbunja, is used as a South Korean traditional medicine to treat acne and inflammatory skin conditions. The antimicrobial activity of RCM root and its active compounds remain unclear. In this study, we prepared a 50% ethanol fraction, ethyl acetate fraction, and acid-treated ethyl acetate fraction (aglycone fraction) of RCM root, and evaluated antibacterial activities against the skin pathogens Staphylococcus aureus, Pseudomonas acnes, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. In a paper disc assay, all fractions of RCM root showed antimicrobial activities against the five skin pathogens. The ethyl acetate fraction displayed 6-, 12-, and 2-fold higher minimal inhibitory concentration (MIC) than the 50% ethanol fraction against S. aureus, E. coli, and P. acnes, respectively. The aglycone fraction displayed 2-fold higher MIC than methyl paraben against P. acnes, S. aureus, E. coli, and P. aeruginosa. The ethyl acetate fraction displayed a minimal bactericidal concentration (MBC) similar to that of methyl paraben, and the aglycone fraction showed 2- to 4-fold higher MBCs than those of methyl paraben. In particular, the ethyl acetate fraction was not cytotoxic and showed thermal stability after incubation at high temperatures ($60-121^{\circ}C$). Finally, the ethyl acetate fraction was separated and four components were identified: procyanidin C, propelagonidin dimer, ellagic acid, and methyl ellagic acid acetyl pentose. The compounds showed high antibacterial activities. These results suggest that RCM root is potentially applicable as a natural preservative in cosmetics.

• Biomolecules & Therapeutics
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• v.30 no.5
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• pp.427-434
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• 2022

The drug repurposing strategy has been applied to the development of emergency COVID-19 therapeutic medicines. Current drug repurposing approaches have been directed against RNA polymerases and viral proteases. Recently, we found that the inhibition of the interaction between the SARS-CoV-2 structural nucleocapsid (N) and spike (S) proteins decreased viral replication. In this study, drug repurposing candidates were screened by in silico molecular docking simulation with the SARS-CoV-2 structural N protein. In the ChEMBL database, 1994 FDA-approved drugs were selected for the in silico virtual screening against the N terminal domain (NTD) of the SARS-CoV-2 N protein. The tyrosine 109 residue in the NTD of the N protein was used as the center of the ligand binding grid for the docking simulation. In plaque forming assays performed with SARS-CoV-2 infected Vero E6 cells, atovaquone, abiraterone acetate, and digoxin exhibited a tendency to reduce the size of the viral plagues without affecting the plaque numbers. Abiraterone acetate significantly decreased the accumulation of viral particles in the cell culture supernatants in a concentration-dependent manner. In addition, abiraterone acetate significantly decreased the production of N protein and S protein in the SARS-CoV-2-infected Vero E6 cells. In conclusion, abiraterone acetate has therapeutic potential to inhibit the viral replication of SARS-CoV-2.

• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.89-94
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• 1982

Among the environmental pollutants, cadmium and lead compounds may impair human health. These compounds may inhibit the biological metabolic function of human body and may furthermore cause the disease directly or indirectly. This study was undertaken to investigate the effects of the immune response by intoxication of cadmium chloride and lead acetate. Cadmium chloride (8.8mg/kg, in saline 10ml) and lead acetate (15mg/kg, in saline 10ml) were administered by intraperitoneal injection. After 3 weeks, the rats were intoxicated with the above chemicals and immunized with sheep RBC. After 4 weeks, the immune response of rat spleen cells was measured by the Jerne's technique. The results were obtained as follows; 1. There was no change in leukocyte counts by the intoxication of cadmium chloride or lead acetate. 2. Cadmium chloride or lead acetate reduced hemoglobin contents for most intoxicated and immunized groups. 3. Hematocrits were decreased by the intoxication of cadmium chloride or lead acetate significantly. 4. It was determined that total protein, A/G (Albumin/Globulin), ${\alpha}-,\;{\beta}-\;and\;{\gamma}$-globulins in rat serum were not changed. 5. Intoxication by cadmium chloride or lead acetate reduced the number of hemolytic plaque to the sheep RBC in rat spleen cells. Therefore, antibody producing of rat spleen cells was suppressed by the intoxication of cadmium chloride and lead acetate.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.5
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• pp.573-579
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• 2014

VFAs like acetate are the major soluble metabolites of food waste leachates after digested. Therefore this study investigates the effect of acetate on growth rate and nutrient removal efficiency of Chlorella vulgaris to treat digested food waste leachates. The initial acetate concentration varied from 0 to 20 mM. As a result, Chlorella vulgaris growth rate was increased as high as the concentrations ranged from 0 to 20 mM. The same trend was observed with $NH_4$-N and $PO_4$-P consumption. The highest growth rate and the highest $NH_4$-N, $PO_4$-P removal rate were observed at acetate concentration of 20 mM. The microalgae growth rate and $NH_4$-N, $PO_4$-P removal rates were 1.5, 1.8, 2.3 times higher than the condition without acetate.

• Applied Biological Chemistry
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• v.39 no.4
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• pp.249-254
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• 1996

The volatile flavor components in mash of nonglutinous rice Takju brewed with or without addition of the starter were determined by GC and GC-MS using polar column. Various kinds of volatile components including alcohols(10), esters(9), organic acids(2) and aldehydes(7) were found in mash of nonglutinous rice Takjus. At the beginning stage of fermentation, 3 to 7 volatile flavor components were detected. The number of volatile flavor components were increased to 26 of to 28 after 16 days fermentation. Early in the brewing, just 3 kinds of flavor components including ethyl acetate, ${\beta}-phenylethyl$ acetate and acetic acid were detected in mash of nonglutinous rice Takju without the addition of the starter, when starter is added additional compounds of alcohol including ethanol were detected, which is suggested to be the effect of flavors originated from the starter. The common flavor compounds through the entire process of fermentation in mash of nonglutinous rice Takju were ethyl acetate, ${\beta}-phenylethyl$ acetate and acetic acid. The relative amount(peak area %) of flavor components were changed with the fermentation period, but the major volatile flavor components were ethyl alcohol, iso-amyl alcohol, hexenyl alcohol, ethyl acetate, ${\beta}-phenylethyl$ acetate and ${\beta}-phenylethyl$ alcohol. The relative amount(peak area %) of ethyl alcohol was the highest in mash of nonglutinous rice Takju with addition of starter. When the starter was not added in the mash of nonglutinous rice Takju, any alcoholic components were not detected in the early stage of fermentation. But the percent of peak area hexenyl alcohol was the highest after 16 days fermentation. Especially few sorts of ester were detected in mash of nonglutious rice Takju without addition of starter by 3 days fermentation.

• Journal of fish pathology
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• v.19 no.3
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• pp.243-251
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• 2006

The internal defense system of mollusks consists of circulating haemocytes. In order to understand the morphological characterization of haemocytes, light and electron microscopy were carried out in oyster, Crassostera gigas. Four types of haemocytes were recognized: type Ⅰ small hyalinocytes, type Ⅱ large hyalinocytes, type Ⅲ large granulocytes and type Ⅳ small granulocytes. Additionally, the activities of alkaline phosphatase (ALP), acid phosphatase (ACP), peroxidase (POD), α-naphthyl acetate esterase, β-glucuronidase, PAS, sudan black B and oil red O in haemocytes were analysed by immunocytochemical methods. The results indicate that enzymatic activities were abundant and more active in granulocytes than in hyalinocytes. After incubation with haemoctyes and Vibrio FKC, phagocytic index and percentage of phagocytic cell were and shown to be increased from 15 to 120 min. In addition, the enzymatic activities were higher than those of controls: ALP, ACP, α-naphthyl acetate esterase and β-glcuronidase, indicating that these enzymes can be related with phagocytosis in oyster.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.1
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• pp.47-55
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• 2009

In this study, the antioxidative effects, inhibitory effects on tyrosinase, and component analysis of fermented Melissa officinalis extracts were investigated. The ethyl acetate fraction of fermented extract ($8.38{\mu}g/mL$) showed the most prominent the free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activities ($FSC_{50}$) of extract/fractions of M. officinalis. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of some M. officinalis extracts on ROS generated in $Fe^{3+}$-EDTA/$H_{2}O_{2}$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction of fermented extract ($0.63{\mu}g/mL$) showed the most prominent ROS scavenging activity. The protective effects of extract/fractions of M. officinalis on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The M. officinalis extracts suppressed photohemolysis in a concentration dependent manner ($5\;{\sim}\;75{\mu}g/mL$). The inhibitory effect of M. officinalis extracts on tyrosinase was investigated to assess their whitening efficacy. Inhibitory effects ($IC_{50}$) on tyrosinase of some M. officinalis extracts was 50 % ethanol extract ($365{\mu}g/mL$) < ethyl acetate fraction of fermented extract ($122.43{\mu}g/mL$) < ethylacetate fraction ($94.8{\mu}g/mL$). Fractions of ethyl acetate both from ordinary and fermented M. officinalis extracts showed 2 band in TLC and 2 peak in HPLC (330 nm). In HPLC chromatogram of ethyl acetate fraction, peak 1 (51.64 %) and peak 2 (48.36 %) were identified as caffeic acid and rosmarinic acid in the order of elution time. Also, in HPLC chromatogram of ethyl acetate fraction of fermented extract, peak 1 (4.13 %) and peak 2 (95.87 %) were identified as caffeic acid and rosmarinic acid in the order of elution time. These results indicate that the component and content of ordinary and fermented extracts of M. officinalis are different. And the extract of M. officinalis can be used as an antioxidant.