• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.25-36
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• 1996

This study was carried out to isolate some bacterial strains which had potentiality of good degrader of fungicides from herbicide free soil and to clarify degradation of a fungicide mycrobutanyl[2-p-chlorophenyl-2-(1H-1,2,4-triazole-1-ylmethyl)-hexanenitrile]. Ten strains of the gram-positive and the gram-negative bacteria were isolated and identified. Most of them vigorously proliferated at 55ppm of mycrobutanil, but the stains were not grown when more than 70ppm of this fungicide were treated Staphylococcus spp. I, Actinobacillus spp. III, and another I of the isolated bacteria degraded more than 35% of the treated mycrobutanil. These three strains could utilize mycrobutanil as nitrogen and carbon sources. Mycrobutanil was rapidly decomposed by these strains when applied once or three times. Tested bacteria gradually increased in growth when mycrobutanil was applied repeatedly. Degradation of mycrobutanil and growth of these bacteria were greater in pH 5.5, and they were high in the order of $28^{\circ}C$ > $18^{\circ}C$ > $38^{\circ}C$.

• Food Science and Preservation
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• v.17 no.3
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• pp.391-397
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• 2010

Yams (Dioscorea spp.) have been used as medicinal and edible resources worldwide. In the present study, methanol extracts were prepared from various kinds of yam, including D. batatas (Gyeongbuk No. 1 and No. 4), D. alata L. (Gyeongbuk No. 5 and No. 6), and D. bulbifera and D. nipponica, and the antioxidant, antithrombin, and antimicrobial activities of these extracts were evaluated. The water content of the various yams was 54.7~83.2% (D. batatas> D. alata L.>D. nipponica>D. bulbifera) and the methanol extracts contained 0.59-1.59% (w/v) solid matter (D. alata L.>D. batatas >D. nipponica>D. bulbifera). The mean concentrations of total polyphenols, total flavonoids, and total sugars in the different types of yam were 49.82 mg/g, 9.79 mg/g, and 173.81 mg/g, respectively. Analysis of DPPH radical-scavenging activity showed that D. alata L. Gyeongbuk No. 6 had a strong antioxidant capacity (IC50=$142.30{\mu}g/mL$), whereas the other yams showed reduced levels of activity (IC50=371-$486{\mu}g/mL$). D. alata L. Gyeongbuk No. 6 showed a strong antithrombin activity against human thrombin. Upon treatment with a D. alata methanol extract (1.5 mg/mL), thrombin time was increased 7.35-fold compared with that when methanol alone was used. In an antimicrobial activity assay, the D. nipponica extract showed moderate antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Proteus vulgaris, and Salmonella typhimurium. Our results indicate that different varieties of Dioscorea spp., including D. batatas, have useful biochemical attributes, including antioxidant, antithrombin, and antibacterial activities.

• The Journal of Dong Guk Oriental Medicine
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• v.6 no.1
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• pp.177-203
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• 1997

Various kinds of medicinal herbs and prescribed herb medicines which have usually been used for treatment of reducing fever, purging intense heat, and detoxication were secreened for antibacterial activity against Proteus vulgaris, S. aureus, and E. faecalis which causing puerperal infection. Minimal inhibitory concentrations of water and ethanol-soluble extracts of Hwangyon(C. japonica), Omae(P. mume), and Omiza(S. chinensis) were determined and using thin-layer chromatography the extracts of Hwangyon and Omiza were separated. The results obtained were as follow : 1. The water-soluble extracts of Keumeunhwa(L. japonica), Chiza(G. jasminoides), Hwangyon(C. japonica), Dansam(S. miltiorrhiza), Omae(P. mume) and Omiza(S. chinensis) showed antibacterial activities against P. vulgaris ; among them, the extracts of Hwangyon, Omae, and Omiza showed high antibacterial activities. The water-soluble extracts of Keumeunhwa(L. japonica), Hwangyon(C. japonica), Hwangkeum(S. baicalensis), Hwangbaek(P. amurense), Dansam(S. miltiorrhiza), Daehwang(R. coreanum), Omae(P. mume), Omiza(S. chinensis), Gingseng(P. ginseng), and Gamcho(G. uralensis) showed antibacterial activities against S. aureus : among them, the extracts of Hwangyon and Omiza showed high antibacterial activities. The water-soluble extracts of Banggi(C. trilobus), Daehwang(R. coreanum), Omae(P. mume), Omiza(S. chinensis), and Gamcho(G. uralensis) inhibited the cell growth of E. faecalis : among them, Omae and Omiza showed high antibacterial activities. The extract of Hwangyon(C. Japonica) and Omae(P. mume) showed no inhibition against E. coli. However, the extract of Omiza(S. chinensis) inhibited cell growth of both E. coli and B. subtilis. 2. The water- and ethanol-soluble extract of Hwangyon(C. Japonica) showed antibacterial activities against P. vulgaris and S. aureus, those of Omae(P. mume) against P. vulgaris and E. faecalis, and those of Omiza(S. chinensis) against all species tested, P. vulgaris, S. aureus, and E. faecalis. With the exception that ethanol-soluble extract of Hwangyon(C. japonica) showed much higher antibacterial activity against S. aureus than water-soluble one, antibacterial activities of both water-and ethanol-soluble ones were similar to each other of other two medicinal herbs. 3. When the prescribed herb medicines were tested, Sambohwan showed antibacterial activities against P. vulgaris and S. aureus. No prescribed herb medicine inhibitied the cell growth of E. faecalis. 4. Minimal inhibitory concentrations(MICs) of both water- and ethanol-soluble extracts of Hwangyon(C. japonica), Omae(P. mume), and Omiza(S. chinensis) against P. vulgaris were $2.5mg/m{\ell}$, $10mm{\ell}$, and $20mg/m{\ell}$, respectively. Those of both Hwangyon(C. japonica) and Omiza(S. chinensis) against S. aureus were $1.25mg/m{\ell}$ and $10mg/m{\ell}$, respectively. MICs of water-soluble extracts of Omae(P. mume) and Omiza(S. chinensis) against E. faecalis were $2.5m{\ell}$ and $5m{\ell}$, and those of ethanol-soluble extracts were $5m{\ell}$ and $10m{\ell}$, respectively Except for those of E. faecalis the cell growth of P. vulgaris and S. aureus were inhibited by much lower concentration of ethanol-soluble extracts used. As a result, the antibacterial compounds against P. vulgaris S. aureus, and E. aecalis are contained in the extracts of Hwangyon(C. japonica), Omae(P. mume), Omiza(S. chinensis), the prescribed herb medicine, Sambohwan, and might be used for treatment of puerperal infection. Further study should be carried out to identify which compounds affect the cell growth inhibition of P. vulgaris S. aureus, and E. faecalis.

• Korean Journal of Microbiology
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• v.50 no.2
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• pp.101-107
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• 2014

Community-acquired antimicrobial resistant bacteria are an emerging problem world-wide. In Korea, resistant bacteria are more prevalent than in other industrialized countries. The aim of this study was to investigate the isolation frequency of methicillin-resistant staphylococci (MRS), Pseudomonas, and Enterobacteriaceae from surrounding environment (home, colleges, public transportation system and possessions) in Seoul, and to examine the level of drug resistance to 13 antimicrobial agents, which are in wide spread clinical use in Korea, as well as new agent, tigecycline in Enterobacteriaceae isolates. Of total 239 samples, 18 (7.5%) MRS, 10 (4.2%) Pseudomonas, and 30 (12.6%) Entarobacteriaceae were isolated. A total of 5 (2.1%) methicillin-resistant S. aureus (MRSA) were detected in home (2 samples), colleges (1 sample), and et cetera (2 sample). A total of 5 (2.1%) Escherichia coli were detected in in home (1 samples), public transportations (3 sample), and et cetera (1 sample). Resistance to cephalosporins, fluoroquinolones, carbapenems, ${\beta}$-lactams, tetracyclines, and aminoglycosides was found in 71.9%, 71.9%, 68.8%, 68.8%, 50.0%, and 25.0% of 32 Enterobacteriaceae isolates, respectively. Also, resistance rate to trimethoprim/sulfamethoxazole of the isolates was a 43.8%. Moreover, 59.4% of the isolates were resistant to new agent, tigecycline and resistance to all agents tested was observed in 3 isolates. Five E. coli isolates were resistant to most of the agents tested, but some of them were susceptible to ciprofloxacin and gentamicin. This study can serve as a data point for future comparisons of possible changes in antibiotic resistance levels in surrounding environment. And multilateral strategies for preventing the incidence and spread of antibiotic resistance are needed.

• Journal of Food Hygiene and Safety
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• v.34 no.6
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• pp.526-533
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• 2019

The purpose of this study was to investigate hazardous microorganisms in mixed baby leafy vegetables and various baby leafy vegetables used as raw materials for fresh-cut produce in spring and summer. To estimate microbial loads, a total of 298 samples including 181 samples of mixed baby leafy vegetables purchased in a Korean market and 117 samples of various baby leafy vegetables from distribution companies were collected. Fecal indicators (coliform and Escherichia coli) as well as food-borne pathogens (E. coli O157:H7, Salmonella spp., Staphylococcus aureus) were enumerated. As a result, the mixed baby leafy vegetable samples showed significantly higher (P<0.05) coliform bacteria numbers in summer (5.59±1.18 log CFU/g) compared to spring (3.60±2.53 log CFU/g). E. coli was detected in 1.3% (1/79) and 42.2% (43/102) of samples collected in spring and summer, respectively. Only one sample collected from a market in spring was contaminated with S. aureus. In the experiment with baby leafy vegetables, the number of coliforms detected in baby leafy vegetables cultivated in soil in spring was 1.15±1.95 log CFU/g, and that in summer was 4.09±2.52 log CFU/g. However, the number of coliforms recovered from baby leafy vegetables cultivated in media was above 5.0 log CFU/g regardless of season. Occurrences of E. coli were 44.4% (12/27) and 19.0% (4/21) for baby leafy vegetables cultivated in soil and media, respectively. However, E. coli O157:H7 and Salmonella spp. were not detected. These results are in relation to microbial loads on mixed baby leafy vegetables associated with raw materials. Therefore, it is necessary to develop and implement hygienic practices at baby leafy vegetable farms to enhance the safety of fresh produce.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.660-665
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• 1999

Structure of water soluble chitosan (WSC) was confirmed by Fourier transform infrared spectrometer (FT-IR), X-ray diffractometer and thermal analyser. The viscosity average molecular weight of WSC ranged from $3.0{\times}10^{4}$ to $4.5{\times}10^{4}$. Using the WSC having viscosity average molecular weight of $3.0{\times}10^{4}$, the antimicrobacterial effects against microorganism and oral microorganism showed 81.7% and 80.6% for Staphyloccus aureus and Bacillus subtilis, respectively, while the anitmicrobacterial effect exhibited 100% and 73.8% against Streptococcus mutans and Streptococcus sanguis, respectively. Therefore it is concluded that WSC is more effective against oral microorganism that microorganism in terms of antimicrobacterial effects. WSC sample with the viscosity average molecular weight of $4.5{\times}10^{4}$ exhibited a half of the antimicrobacterial effect of the low MW sample, indicating that the WSC with low MW was better than that with high MW. Chitin and chitosan showed a drastic decrease of acidity from pH 7.0 to 4.9 after 8 minute incubation time and reached an equilibrium after that. WSC, however, restrained pH of the sample from lowering up to about 16 minutes of incubation and reached an equilibrium after that. WSC obviously showed a buffering effect against pH change.

• Tuberculosis and Respiratory Diseases
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• v.58 no.2
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• pp.167-173
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• 2005

Background : Airborne particles during Yellow Sand phenomena are known to be associated with the respiratory disease. The purpose of this study was to evaluate the concentration and metal component properties of Yellow Sand particles and compare with airborne microbial concentration and species in non Yellow Sand and Yellow Sand phenomena. Methods : Samplings were carried out in 2002 in Seosan, during non Yellow Sand and Yellow Sand phenomena. Samples were taken using the 8-stage Cascade impactor and metallic elements were analyzed by XRF. Those were culture on the media for bacterial and fungal culture and celline for virus. Results : The concentration of total suspended particulate matter were respectively $80.2{\mu}g/m^3$, $40.3{\mu}g/m^3$ in non Yellow Sand and Yellow Sand phenomena. The concentration of metallic elements such as Ca, Fe, Cu and Zn in Yellow Sand phenomena were higher than its in non Yellow Sand. Two bacteria, Bacillus species and Staphylococcus were grown in two periods. In both periods, several fungal spores(Mucor species, Cladosporum, Alternaria, Aspergillus, Penicillium, and Alternaria species) were identified. The differences of bacteria and fungus species not observed in Yellow Sand and non Yellow Sand. Any viruses were not isolated in between both periods. Conclusions : The concentration of total suspended particulate matter and some metallic elements in Yellow Sand phenomena were higher than its in non Yellow Sand. The difference of bacteria and fungus species was not observed in non Yellow Sand and Yellow Sand phenomena.

• Journal of Animal Environmental Science
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• v.10 no.2
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• pp.87-92
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• 2004

This research was carried out to investigate the effects of ozone and anion treatments in improving the quality of the drinking water far livestock. The drinking water was treated with an ozone concentration of 0.658 $\~$0.722 g/h and with anion of 3.27 $\~$ 6.17$\times$1,000,000 pieces/sec. With the ozone and anion treatments, the pH was significantly increased from a range of pH 6.38 $\~$ 7.14 to a range of pH 7.5 $\~$ 7.8(P<0.05). Also, with the ozone and anion treatments, the dissolved oxygen (DO) concentration in the drinking water was increased from a range of 2.0 $\~$ 3.5 mg/$\iota$ to 5.5 $\~$ 6.1 mg/$\iota$(P<0.05): the DO decreased in the control. The dissolved ozone was not increased in the beginning of the experiment, but was increased by 0.48$\~$0.56 mg/L after 48 h of the ozone and anion treatment. The colony numbers of Staphylococcus aureus, Salmonella enteritis, and Escherichia coli disappeared after one hour of ozone and anion treatment.

• Culinary science and hospitality research
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• v.15 no.4
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• pp.1-8
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• 2009

The aim of this study is to investigate the microbial contamination assessment of raw Jinmichae to cook and to establish its control. Three kinds of Korean Jinmichae products(K1, K2, K3) and three kinds of imported Jinmichae products(Chile: F1, Peru: F2, Mexico: F3) were collected from markets and department stores in Seoul and Gyeonggi-do. The results were as follows; Aerobic mesophilic bacteria in raw Jinmichae(F2) was detected $7.20{\times}10^7$ CFU/g, which exceeded the acceptable standard level, $1.0{\times}10^6$ CFU/g. The rest of raw groups fell up to $1.0{\times}10^3{\sim}1.0{\times}10^4$ CFU/g. Aerobic mesophilic bacteria were detected in blanched and fried Jinmichae groups. Boiled Jinmichae group did not exceed the acceptable standard level of $1.0{\times}10^6$ CFU/g. However, all the fried groups exceeded the level. E. coli were detected in raw Jinmichae but it was able to be controlled by blanching. Unlike this, E. coli was not completely controlled by roasting for 20 seconds relative to 40, 60 seconds. S. aureus were effectively controlled by boiling, however, it was not controlled by roasting. After roasting Jinmichae for 60 seconds, S. aureus were detected in the half of all groups. In this study, Jinmichae were found to be favorable one of side dishes in school meal service. Jinmichae can be contaminated by microbial pathogens such as S. aureus, E. coli, etc. Therefore, further studies are needed to monitor microbial pathogens and to provide their control.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.170-175
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• 2009

The extract of Platycarya strobilacea is known to possess a wide range of pharmacological activities including anti-inflammatory, anti-fungal, and anti-cancer properties. We have reported that the ethyl acetate fraction of Platycarya strobilacea (PS-ET fraction) has high potential as an antioxidant agent (J. Soc. Cosmet. Scientists Korea 34(4) 275, 2008). In this study, antibacterial activity of the fraction and stability of the cream containing 0.2% PS-ET fraction were investigated for the application to cosmetics. Antibacterial activity of PS-ET fraction against various skin pathogenic bacteria (Propionibacterium acnes, Staphylococcus aureus, and Pityrosporum ovale) was measured by minimum inhibitory concentration (MIC). MIC values of PS-ET fraction on P. acnes, S. aureus, and P. ovale were 0.13%, 0.06% and 0.25%, respectively. The results showed that the antibacterial activity of the fraction was the highest in the S. aureus. For the stability evaluation, pH and viscosity of the cream containing 0.2% PS-ET fraction were measured. The results showed that pH changes of the cream containing PS-ET fraction was lower than the control cream without PS-ET fraction. And the PS-ET fraction could repress the decrease of viscosity of the cream against sunlight treatment. These results suggest that the fraction of Platycarya strobilacea has high potential as bactericide against the skin pathogenic bacteria and could be added to improve the stability of cosmetic products.