• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.452-460
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• 2018

This study was conducted to investigate the physiological activities of Houttuynia cordata extracts and fractions. H. cordata extracts were extracted with 50% ethanol and the ethyl acetate fractions were obtained from the extracts. Minimum inhibitory concentration (MIC) values of the ethyl acetate fraction for S. aureus and B. subtilis were $78{\mu}g/mL$ and $312{\mu}g/mL$, respectively, indicating the high activity against gram-positive bacteria. The free radical scavenging activity ($FSC_{50}$) for 1,1-diphenyl-2-picrylhydrazyl (DPPH) was higher in the ethyl acetate fraction with $12.00{\mu}g/mL$ compared to that of $27.15{\mu}g/mL$ for 50% ethanol extract. The total antioxidant activity ($OSC_{50}$) values for reactive oxygen species (ROS) produced in $Fe^{3+}-EDTA/H_2O_2$ system by a luminol-dependent chemiluminescence method were 2.91 and $0.983{\mu}g/ml$ for the 50% ethanol extract and ethyl acetate fraction, respectively. To investigate cellular protective effects on the HaCaT cell, the intracellular ROS scavenging activity was measured after UVB irradiation and the ethyl acetate fraction of H. cordata showed the activity in a concentration-dependent from $1.6{\mu}g/mL$ and a reduction rate of 54.3% at a maximum concentration of $12.5{\mu}g/mL$. Also, HaCaT cell protective effect against $H_2O_2$-mediated decreased the cell viability of the ethyl acetate fraction of H. cordata which significantly increased the cell viability from $0.8{\mu}g/mL$ and the maximum cell viability showed 86.9%. The ethyl acetate fraction of the H. cordata extracts was analyzed by TLC and HPLC. As a result, quercitrin, isoquercitrin, hyperoside, chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, rutin and afzelin were identified. From the above results, it was suggested that the extracts and fractions of H. cordata have a potential to be applied in the field of cosmetics as a natural antioxidant/preservative capable of protecting the cell membrane from the oxidative stress by eliminating ROS and exhibiting the antimicrobial effect.

• Food Science of Animal Resources
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• v.26 no.4
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• pp.418-425
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• 2006

This study was conducted to evaluate extraction properties of crude saponin and ginsenosides, and their effects on sensory properties of emulsified pork sausage. Non-dried ginseng root was boiled in 0 (e.g., 100% distilled water), 20, 40, 60, 80 or 100% ethanol, and powdered by a freezing dry method. Weight of dried powder for the 0% ethanol extraction was 20% of initial non-dried ginseng weight, while $20{\sim}80%$ and 100% ethanol extractions resulted in approximately 15 and 10% of their initial weights, respectively. On the other hand, crude saponin content in the dried powder was linearly increased for a higher ethanol content where 100% ethanol extraction resulted in 123.52 mg/g. LC/MS analysis of crude saponin for quantifying ginsenosides showed that Rb1, Rb2 and Rc were significantly (p<0.05) higher levels for both 80 and 100% ethanol extractions. In the case of Rg1 ginsenoside, 60, 80 and 100% ethanol extractions resulted in significantly (p<0.05) higher levels. Emulsified pork sausages containing 0, 1 or 2% ginseng extracts were smoked or non-smoked and their sensory characteristics and preference were evaluated. Smoking process significantly (p<0.05) decreased juiciness and tenderness, but the treatment significantly (p<0.05) improved flavor and consumer preference. It was particularly noticed that a 2% addition of ginseng extract prevented the adverse effects of smoking process on juiciness and tenderness while the 2% addition significantly (p<0.05) improved consumer preference. The current results implied that addition of ginseng extract in emulsified pork sausage could improve sensory quality.

• Preventive Nutrition and Food Science
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• v.22 no.3
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• pp.203-210
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• 2017

The antioxidant and antimicrobial activities of three kinds of strawberry ethanol extracts from Robus corchorifolius L. f. (RCL), Rubus parvifolius L. var. parvifolius (RPL), and Duchesnea chrysantha Miq. (DCM) were investigated. The RPL was highest (P<0.05) in phenolic, flavonoid, and anthocyanin contents. 2,2-Diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activities of RPL and DCM extracts were higher than that of RCL (P<0.05). Hydrogen peroxide scavenging activity of RPL was high compared to DCM and RCL (P<0.05). RCL exhibited a significant (P<0.05) potent antioxidant activity in nitric oxide radical inhibition. Inhibition diameter zone (nearest mm) of extracts against the test bacteria ranged from 11.5 in RCL to 12.5 in DCM against Staphylococcus aureus, from 10.5 in RCL to 13.5 in DCM against Streptococcus pneumoniae, from 8.5 in DCM to 10.5 in RCL against Escherichia coli, and the same inhibition of 10 mm in three of the extracts against Klebsiella pneumoniae. However, there was no inhibition against fungi Aspergillus niger and Candida albicans. Three of the extracts had the same minimum inhibitory concentration values of 12.50, 12.50, and $6.25{\mu}g/mL$ against S. aureus, K. pneumoniae, and S. pneumoniae, respectively. On the other hand, MIC values of 12.50, 12.50, and $6.50{\mu}g/mL$ were recorded for RPL, DCM, and RCL against E. coli, respectively. The result of present study revealed that extracts from three kinds of strawberries could be potential candidates as antioxidant and antimicrobial sources for functional food industries.

• Natural Product Sciences
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• v.24 no.3
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• pp.159-163
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• 2018

Two new polyketides, chinoketides A and B (1 - 2) with a known compound xylarphthalide A (3), were isolated from the solid medium of the endophytes from the leaves of the relic plant Distylium chinense with the "black-box" co-culture method, and the structures of two new compounds were elucidated by NMR, MS and CD spectra. And the absolute configurations of chinoketides A (1) and B (2) were determined as 2R,3R,8S and 5R,6S by calculating their ECD spectra to compare with the experimental CD spectra. Finally, the antimicrobial activities were evaluated to Erwinia carotovora sub sp. Carotovora (Jones) Bersey et al, and the results showed that compounds 1 - 3 displayed the antimicrobial activities with MIC value at 20.5, 30.4 and $10.2{\mu}g/mL$.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.24-27
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• 2009

Solid-state dye-sensitized solar cells (DSSCs) have been constructed employing supramolecular electrolytes with multiple hydrogen bonding. A supramolecule was facilely synthesized by one-pot reaction between the amines of methyl isocytosine (MIC) and the epoxy groups of poly(ethylene glycol diglycidyl ether) (PEGDGE) to produce quadruple hydrogen bonding units. Hydrogen bonding interactions and dissolution behavior of salt in supramolecular electrolytes are investigated. The ionic conductivity of the supramolecular electrolytes with ionic liquid, i.e. 1-methyl-3-propylimidazolium iodide (MPII) reaches $8.5{\times}10^{-5}$ S/cm at room temperature, which is higher than that with metal salt (KI). A worm-like morphology is observed in the FE-SEM micrographs of $TiO_2$ nanoporous layer, due to the connection of $TiO_2$ nanoparticles resulting from adequate coating by electrolytes. DSSCs employing the supramolecular electrolytes with MPII and KI exhibit an energy conversion efficiency of 2.5 % and 0.5 %, respectively, at 100 $mW/cm^2$, indicating the importance of the cation of salt. Solar cell performances were further improved up to 3.7 % upon introduction of poly(ethylene glycol dimethyl ether) (PEGDME) with 500 g/mol.

• Journal of Life Science
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• v.8 no.6
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• pp.648-653
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• 1998

The development of natural food preservatives instead of chemical synthetic food preservatives is world wide inte-rest. Authors already investigated that cinnamon bark extract revealed antimicrobial activity against general spoilage microorganisms of food especially its acitivity was stronger against molds than against bacteria. In this paper, authors examined the mirobial flora from the spoiled fish meat paste products and also checked the possibility of cinnamon bark extract food preservative for prolong the shelf life of the fish paste product and breads. The predominat bacteria was Bacillus sp. as about 98% of the total microorganisms isolated from unpacked or packed spoiled fish meat paste products. While molds and yeast are not detected from the vacuum packed products. The MIC(minimum inhibitory concentration) of cinnamon bark extract against the isolated spoilage bacteria and molds was 160~640$\mu\textrm{g}$/$m\ell$ and 40~80$\mu\textrm{g}$/$m\ell$, respectively. When the diluted cinnamon bark extract (the extract : ethanol=1 : 3) was sprayed on the surface of fried fish meat paste product, molds growth was delayed by 2 days at room temperature. The shelf lifes of sandwich and glutinousrice bread which surface sprayed with the diluted extract(1 : 1) was extended by 5 and 7 days, respectively.

• Journal of Life Science
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• v.8 no.5
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• pp.520-525
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• 1998

Effects of plant growth regulators and anti-oxidants for rapid multiplication of Cymbidium kanran were investigated. The best gelling agent was 2.5 g/1 gelrite which needed less quantity (about 28%) and half price than 9 g/1 chemi-cal agar. Undefined edible agar was only a little bit worse than chemical agar in growth, but the price was half as much as the latter. The higher concentration of BA and NAA, the deeper browning of medium that prevented from performing its functions of plant growth regulators. Polyvinylpyrrolidone (M.W. 40,000) was the most effective anti-oxidant other than ascorbic acid, aspartic acid, and rutin in protecting the browning of medium, enhancing the effect of plant growth regulators, and thus prolonging the subculture cycle. Vigorous seedlings were obtained by 0.1∼1.0 mg/1 BA,0.1 mg/1 NAA and 1 g/1 polyvinylpyrrolidone treatments. Therefore, the best result for growth and econo-mic aspects in rhizome culture of Cymbidium kanran were obtained by using MS basal medium with 2.5 g/1 gelrite, 1 g/1 polyvinylpyrrolidone, 0.1∼1.0 mg/1 BA and 0.1 mg/1 NAA.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.143-147
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• 2003

Sensitivity of Phytophthora infestans isolates to fungicides metalaxyl and ethaboxam in Korea was examined with 260 isolates for 3 years (9 isolates in 2000,93 isolates in 2001, and 158 isolates in 2002). Both Al and A2 mating types were found from the isolates collected for 3 years. Al mating type was dominant in the population with 8 isolates (88.9%) in 2000, 84 isolates (89.4%) in 2001, and 138 isolates (87.3%) in 2002. Only some isolates from diseased tomatoes in Buyergun and diseased potatoes in Pyeongchanggun were of the A2 mating type. As for metalaxyl sensitivity, 77.0% of the isolates were moderately resistant with 8 isolates (88.9%) in 2000, 73 isolates (77.7%) in 2001, and 120 isolates (75.9%) in 2002. Meanwhile, those found resistant were 1 isolate (11.1%) in 2000, 16 isolates (17.0%) in 2001, and 33 isolates (20.9%) in 2002. Only 5 isolates (3.2%) were sensitive to metalaxyl in 2002. There was no significant difference in the sensitivity among years. As for ethaboxam, no isolate was able to grow at 5.0 $\mu\textrm{g}$ /ml, and only four isolates (1.5 %) grew at 1.0 $\mu\textrm{g}$ /ml with heavy retardation compared with the untreated control. Based on these 3-year results, the minimum inhibitory concentration (MIC) of ethaboxam to p. infestans was determined to be 0.2-1.0 $\mu\textrm{g}$ /ml. Results indicate that resistance development by p. infestans to ethaboxam is not likely to occur in the natural condition. furthermore, there was no indication of cross resistance between metalaxyl and ethaboxam because all the isolates, regardless of classification for their sensitivity to metalaxyl, were not able to grow at 5.0 $\mu\textrm{g}$ /ml of ethaboxam.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.174-179
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• 1997

The antimicrobial and GTase(Glucosyltransferase) inhibition activity were investigated for solvent fractions of Gall-nut, variety of fork drugs and Red-grape husk water extracts. Among them, Gall-nut and Red-grape husk water extracts were selected for the powerful antimicrobial and GTase inhibition activity. The methanol fractions of Gall-nut and Red-grape husk were showed very powerful antimicrobial activity on both B. subtilis and E. coli. The MIC(Minimum Inhibitory Concentration) of gall-nut methanol fraction were 1.0mg/ml for B. subtilis and 3.0mg/ml for E. coli. Red-grape husk were 2.0mg/ml for B. subtilis and 3.0mg/ml for E. coli. The methanol fractions of Gall-nut and Red-grape husk were showed very powerful Gtase inhibition activity. The concentrations of these fractions for 80% inhibition of GTase activity were 1.08$\times$10-3mg/ml and 1.08$\times$10-2mg/ml, respectively. The principal compound for the antimicrobial and GTase inhibition activity in tese extracts seems to be polyphenol derivatives.

• Korean journal of food and cookery science
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• v.19 no.4
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• pp.470-476
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• 2003

Daehwang (Rheum tanguticum) was extracted by methanol, and the antimicrobial activities of the extract, against some food hazardous microorganisms, were investigated by the paper disc method. The minimum inhibitory concentration (MIC) of the extract against the microorganisms was determined, and the extract components were analyzed by GC/MS. The Daehwang extract showed the strongest antimicrobial effect against P. aeruginosa. The MICs on S. aureus, P. aeruginosa and S. typhimurium were 250, 300 and 300mg/$m\ell$, respectively. In the methanol extracts from Daehwang, 120 different compounds were separated, with the extraction yield of the phenolic compounds being relatively high (29.85%). Substances with antimicrobial activity, such as 2-methoxy-phenol and 4-vinyl-2-methoxy-phenol were detected in the study.