• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1797-1804
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• 2007

Lycopene, an acyclic carotenoid found in tomatoes (Lycopersicon esculentum) and a number off fruits, has shown various biological properties, but its antifungal effects remain poorly understood. The current study investigated the antifungal activity of lycopene and its mode of action. Lycopene showed potent antifungal effects toward pathogenic fungi, tested in an energy-independent manner, with low hemolytic effects against human erythrocytes. To confirm the antifungal effects of lycopene, its effects on the dimorphism of Candida albicans induced by fetal bovine serum (FBS), which plays a key role in the pathogenesis of a host invasion, were investigated. The results showed that lycopene exerted potent antifungal activity on the serum-induced mycelia of C. albicans. To understand the antifungal mode of action of lycopene, the action of lycopene against fungal cell membranes was examined by FACScan analysis and glucose and trehalose-release test. The results indicated that lycopene caused significant membrane damage and inhibited the normal budding process, resulting from the destruction of membrane integrity. The present study indicates that lycopene has considerable antifungal activity, deserving further investigation for clinical applications.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.278-285
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• 1998

The microdilution assay recommended by NCCLS (National Committee for Clinical Laboratory Standards) is one of the standardized methods of antibiotic susceptibility test. This method has been widely used clinically to obtain MIC values of antibiotics on pathogenic microorganisms. It is more convenient, rapid and simple to test many samples than other test methods such as agar diffusion assay and broth macrodilution assay. The screening of antimicrobial agents from microbial extracts is too laborious in its process. Therefore, a number of screening methods having more simple procedure have been developed. In our laboratory, we applied microdilution assay for screening the antimicrobial agents. This assay showed dose-response results and was more sensitive than disc diffusion assay in our system. We tested 200 samples of microbial extracts originated from 100 microbial strains and selected several samples as potential candidates. In this report, we show that the microdilution assay is more convenient method in screeing of antibiotic susceptibility than those previously reported.

• Journal of the Korean Applied Science and Technology
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• v.26 no.3
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• pp.350-356
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• 2009

The objection of this research is to conform of practicable possibility and recycling of producing junk after citrus fruits is processed. In the middle of practicable possibility, with verification of antibiosis that tactiling sensibility in a microorganism. With extracting d-limonene oil that have 70${\sim}$90% a component of oil out of junk citrus peel, making certain the about 12000ppm(1.2%) concentration of it. By means of antibiosis property over the a pathogenic bacterium as well as a residence bacterium, considerating the limit of application against daily living supplies needs to antibiosis. Antibiosis effect of a stationing bacterium in the body permanently and by means of antibiosis verification of special bacteria Propionibacterium Acnes that causative skin trouble is selected, in based the antibiotic sencitivity test check up result of minimal inhibitory concentration(MIC).

• Journal of Animal Environmental Science
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• v.19 no.2
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• pp.183-190
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• 2013

Establishment of a new concept of environmental friendly livestock manure management is required based on the facts. But now liquid fertilizer quality in korea shows a large difference among regions and the regulations are uncertain. Focusing on precedent study on main level-grading factors of liquid fertilizer quality certification, the study collected laws and standards related to liquid fertilizer of livestock manure at home and abroad and produced evaluation standards. Liquid fertilizer was divided into four factors (fertilizing value, harmfulness, stability and uniformity). According to each item, scores were awarded based on 16 details: fertilizing value (Nitrogen concentration, the whole concentration of Nitrogen, Phosphoric acid and Kalium), harmfulness (heavy metals, pathogenic microorganism and antibiotics), stability (maturity degree and odour), uniformity (EC, BOD, SS, moisture content and salt). The grade of liquid fertilizer, A (42~48), B (34~41), C (26~33) were rated using total scores.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.3
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• pp.84-93
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• 2003

Photoreactivation of microorganism following UV-disinfection is one of the research topics of interest in assessing the UV-disinfection performance. Apparent photoreactivation was examined under fluorescent lamp and solar radiation as well as in darkness. Total coliform, fecal coliform, and Escherichia coli were used as indicator microorganisms, and their concentration was monitored with time after UV-disinfection. Under the darkness, their initial concentration of 10∼30 MPN/100 mL increased to the level of 100 MPN/100 mL after 24 hours, which implied that part of damaged microorganisms by UV-disinfection might be repairable with time. Under the fluorescent lamp, photoreactivation was more apparent that their concentration increased up to 1,000 MPN/100 mL which might significantly impair the water uses specially in reuse of reclaimed wastewater. However, their concentration further decreased down to below 2 MPN/100 mL under the solar radiation primarily due to additional disinfection by solar radiation rather than photoreactivation. Samples not disinfected by UV-disinfection also demonstrated substantial decrease of their concentration under solar radiation from about 5,000 MPN/100 mL to less than 30 MPN/100 mL in 24 hours. But direct reuse of effluent without disinfection is not recommended because natural decay by solar radiation may take time and be affected by climatic conditions. The result suggests that photoreactivation of pathogenic microorganisms may not be concerned in agricultural reuse of reclaimed wastewater because solar radiation may provide further disinfection after UV-disinfection.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.222-227
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• 2017

This study aimed to explore the potential for food-industry application of atmospheric pressure dielectric barrier discharge plasma (atmospheric pressure DBD plasma) as a non-thermal sterilization technology for microorganism. The effects of the key parameters such as power, oxygen ratio, exposure time and distance on Escherichia coli KCCM 21052 sterilization by the atmospheric pressure DBD plasma treatment were investigated. The experimental results revealed that increasing the power, exposure time or oxygen ratio and decreasing the exposure distance led to an improvement in the sterilization efficiency of E. coli. Furthermore, the atmospheric pressure DBD plasma (1.0 kW power, 1.0% (v/v) $O_2$, 5 min exposure time and 20 mm exposure distance) treatment was very effective for the sterilization of food-borne pathogenic bacteria. The sterilization rate of E. coli, Bacillus cereus KCCM 40935, Bacillus subtilis KCCM 12027, Bacillus thuringiensis KCCM 11429 and Bacillus atrophaeus KCCM 11314 were 72.3%, 74.6%, 88.5%, 84.7% and 91.3%, respectively.

• Korean Journal of Food Science and Technology
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• v.47 no.5
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• pp.574-578
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• 2015

The purpose of this study was to examine the antimicrobial effects of natural additives on pathogenic microorganisms in commercial chicken during storage. Chicken skin ($20cm^2$) inoculated with Salmonella Typhimurium or Pseudomonas aeruginosa was treated with 2% natural additives, including chitosan, epigallocatechin gallate (EGCG) and garlic, during storage at $4^{\circ}C$ for 12 days. A combination of the three natural additives significantly inhibited growth of S. Typhimurium compared to treatment with chitosan, EGCG or garlic alone (p<0.05). This combination also inhibited growth of P. aeruginosa compared to treatment with one or two of the natural additives (p<0.05). These results suggest that combined chitosan, EGCG, and garlic may be used as an antimicrobial agent in commercial chicken during refrigerated storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.261-269
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• 2012

In this study, 18 kinds of Korean medicinal herb extracts were examined for anti-microbial activities against pathogenic microorganisms. The methanol (MeOH) extracts from Schizandra chinensis, Rhus javanica and Caesalpinia sappan exhibited antimicrobial activities against most pathogenic microorganisms at concentrations of 5 mg/mL, whereas the other 15 extracts exhibited anti-microbial activities at concentrations of 30 mg/mL. The minimum concentration at which Schizandra chinensis extracts inhibited for S. epidermidis and Bor. bronchiseptica was 0.6 mg/mL. The MeOH extracts from Schizandra chinensis, Caesalpinia sappan, Rhus javanica and Seutellaria baicalensis which had higher anti-microbial activities were subsequently fractionated using 5 different solvents, and further screened for anti-microbial activities. The inhibitory effects of ethyl acetate (EtOAc) extracts on microbial growth were greater compared to any other solvent extracts. In order to investigate the inhibitory effect of Korean medicinal herbs with high anti-microbial activities on microbial proliferation, the MeOH extracts at concentrations of 0, 100, 300 and 500 ppm were added to the media. No addition of extracts caused rapid growth of microbes after 12 hours incubation. As the concentration of extracts from Rhus javanica and Caesalpinia sappan increased, the growth-inhibiting effect on gram-positive bacteria including S. aureus, S. epidermidis, and L. monocytogenes was prominent. Rhus javanica extracts exhibited growth-inhibiting activity for gram-negative bacteria including Sal. Pullorum and Sal. Choleraesuis. The low concentration of extracts from Rhus javanica and Caesalpinia sappan exhibited the growth of Bor. bronchiseptica and E. coli serotype $O_8$. However, the higher concentration of extracts from Rhus javanica and Caesalpinia sappan exhibited a strong inhibitory effect on microbial proliferation.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.240-246
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• 2012

This study evaluated the efficacy of strong acidic electrolyzed water (SAcEW), low alkaline electrolyzed water (LAlEW) and aqueous chlorine dioxide (ACD) for reducing pathogenic bacteria($Escherichia$ $coli$, $Bacillus$ $cereus$, $Salmonella$ Typhimurium, $Stapylococcus$ $aureus$) on Chinese cabbage. Artificially inoculated Chinese cabbage was immersed for 1, 5 and 10 min with TW, NaClO, EW and ACD. Generally, leaves showed more effective reduction than stems. Regarding the inhibitory effect, ACD treatment showed the highest effects rather than other treatments. When Chinese cabbage was immersed for 3 min in sterilized water, it was reduced to a minimum of 1.33 log CFU/g at LAlEW and a maximum of 4.70 log CFU/g at ACD. Compared to NaClO, ACD and LAlEW which showed a reduction of 3.2 log CFU/g ($Sal.$ Typhimurium) and 2.7 log CFU/g($B.$ $cereus$), respectively. Furthermore, the others had similar inhibitory effects compared to NaClO.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.97-102
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• 2003

Raw and washed spinaches were tested to evaluate the incidences of Aeromonas hydrophila, Escherichia coli O157:H7, Plesiomonas shigelloides, Pseudomonas aeruginosa, Salmonella spp., Shigella spp., Yersinia enterocolitica, Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Listeria monocytogenes, and Staphylococcus aureus. Four pathogenic bacteria were isolated from spinach samples, and identified by morphological and biochemical methods, including API and ATB identification systems. Isolates from MacConkey, Cereus Selective, Clostridium Perfringens, and Baird-Parker agar media were in 99.9, 99.8, 99.9, and 97.8% agreements with A. hydrophila, B. cereus, C. perfringens, and S. aureus at the species level, respectively. SET-RPLA revealed, among the five strains of S. aureus isolates, two produced type A enterotoxin. All five strains of B. cereus isolates produced enterotoxin as revealed with CRET-RPLA.