• Journal of Environmental Health Sciences
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• v.36 no.3
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• pp.229-235
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• 2010

Efforts to evaluate water pollution using indicator microorganisms have been underway for decades, and driven by research on water purity control applications, water quality criteria are growing more and more strict. Furthermore, recent reports indicate that high concentrations of antibiotics are not absorbed, and are present in excrement from animals and humans dosed with unnecessarily high levels of antibiotics. This has emerged as very important issue from the standpoint of being an ecological and health hazard. In this study, water pollution was analyzed through physicochemical and microbiological means, and antibiotic resistance in indicator microorganisms was assessed. In physicochemical analysis, biochemical oxygen demand (BOD)$_5$ and chemical oxygen demand (COD)$_{Mn}$ evaluation showed that pollution by organisms was highest at the G1 location with a high human population, and the DP location which has many livestock-containing households. The indicator organism levels at the G1 location were: Total Coliforms (1205 colony forming units (CFU)/100 ml), Fecal Coliforms (270 CFU/100 ml), Escherichia coli (253 CFU/100 ml) and Fecal Streptococci (210 CFU/100 ml), while for the DP location levels were: Total Coliforms (1480 CFU/100 ml), Fecal Coliforms (438 CFU/100 ml), E. coli (560 CFU/100 ml), and Fecal Streptococci (348 CFU/100 ml). Levels of fecal indicator microorganisms such as Fecal Coliforms, E. coli and Fecal Streptococci were high at all locations in the fall (the period after the rainy season), and the yearly distribution was similar between these organisms. If the number of livestock-containing households was high, almost all strains of E. coli (as distinct from the other indicator organisms) showed resistance to antibiotics, with the degree of resistance varying between areas. E. coli strains from the OY area in particular, which has a high population density, showed strong resistance to AM10 and Va30. While strong antibiotic resistance was observed overall at the DP and OY locations, no resistance was observed at the EB location.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1158-1165
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• 1997

This study was designed to investigate the changes in microflora and enzyme activities of traditional kochujang during aging, which was prepared with a meju fermented for various periods of time. The number of bacteria was highest in all samples after 30 days of fermentation at $20^{\circ}C$, while that of mold in kochujang prepared with a 40-day- or 60-day-fermented meju was highest at 15th day of aging when yeast appeared. The activities of carbohydrases and proteases were highest in kochujang prepared with a 40-day-fermented meju followed by a 60-day-fermented meju. These results suggest that kochujang prepared with a meju aged for 40 days had the highest quality in terms of physicochemical, microbiological and enzyme activities of kochujang during fermentation.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.254-259
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• 2003

Effects of freeze-drying on microbiological and sensory characteristics of yulmoo-kimchi (leaf radish kimchi) were investigated. Freeze-dried yulmoo-kimchi was stored at 0, 10 or $25^{\circ}C$ for 60 days and rehydrated with water. Optimum rehydration time of freeze-dried yulmoo-kimchi was 2 hr. Number of lactic acid bacteria of freeze-dried, 10 days-stored, rehydrated yulmoo-kimchi decreased significantly (p<0.05) in comparison with that of reference sample (non-freeze-dried yulmoo-kimchi), while no significant changes were observed after 10 days. As storage temperature increased, number of lactic acid bacteria of 10 days-stored samples decreased. pH value slightly increased by freeze-drying, while it decreased gradually during 60 days of storage. Sensory properties of freeze-dried/rehydrated sample were slightly inferior to those of reference sample, but those were relatively good when the sample was evaluated solely. Overall acceptability of freeze-dried, $0^{\circ}C$-stored, rehydrated sample was significantly inferior to reference sample (p<0.05) and it gradually decreased as storage temperature increased. Between storage periods of 10 through 60 days, sensory properties of 0 and $10^{\circ}C$-stored sample slightly decreased, while those of $25^{\circ}C$-stored sample decreased markedly.

• Korean Journal of Microbiology
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• v.53 no.1
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• pp.1-8
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• 2017

Measles virus is a highly contagious, exanthematic virus, preventable by the use of an effective live-attenuated vaccine. However, measles virus remains endemic in many area of the world causing nearly 200,000 deaths per year and still a major cause of child mortality, mostly in developing countries. In March 2014, Republic of Korea was certified as a 'national measles elimination' by the WHO as a result of a high-quality case-based surveillance system and population immunity, which was achieved by a high vaccination rate (>95.0% since 1996). But, since the beginning of 2014, the Gyeonggi province has experienced a resurgence of measles cases. In this study, we investigated the characteristics of measles viruses isolated from confirmed measles in Gyeonggi province during January 1, 2014 ~ July 31, 2014, 60 isolates were obtained from 72 confirmed measles specimens. Genotypic distributions and genetic diversities of isolated measles virus were analyzed by sequencing of nucleoprotein (N) gene. 58 (96.7%) imported cases were identified. The predominant genotype was B3, which reflects the circulating measles virus in adjacent countries. The sequences of nucleoprotein (N) gene of isolated MeV were showed that the strains characterized showed the highest degree of identity (99%) with the Philippine related strains in 2013-2014. Therefore, infected traveler returning from the Philippines transmitted secondary infection in Korea.

• Journal of Life Science
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• v.16 no.1
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• pp.141-147
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• 2006

The effect of traditional Doenjang supplemented with the extracts of herb medicines (refer as DHM) on the taste component and microbial properties was investigated. The DHMs were divided to four group. Fatty acid compositions were similar between DHMs and control as ratio of each fatty acid to total fatty acids. Concentration of total free amino acid from groups II , III and IV was higher than that of control. Major organic acids were phytic acid, lactic acid, and butyric acid. In isoflavone of DHMs, free daidzein and genistein contents were mostly similar among the groups, and groups m and W were slightly higher as compared with control. Viable cell count of DHMs was shown to be $2.5\times10^7\;CFU/ml$, a similar trend of control. Protease activity of DHMs was higher than that of control(67.65 units), but amylase activity between DHMs and control was almost identical Sensory scores of group II and IV were shown to be brighter than those of group I and II, and decreasing off-odor was more effective. In over all eating-quality, group III and IV were evaluated to be favorable as compared with control and the other DHMs because of supplementing the sweet taste of extracts to Korean indigenous Doenjang.

• Korean Journal of Oriental Medicine
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• v.12 no.1
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• pp.49-57
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• 2006

Objectives : This study has attempted to establish an organized system for the microbiological quality of raw materials which are important factors in preparing the standard for microbial limits. Methods : This study has first set up microbial contamination limit test. total aerobic microbial count and total fungi count, int accordance with testing method of the Korea Pharmacopeia 8th edition in order to establish an inspection standard for microbial contamination. Results : The microbial contamination of 18 items that are highly prone to contamination by three regions(Seoul, Daejeon, Gyeongsangbuk-do), As a result, Morus alba Linne and Rehmannia glutimosa Liboschitz var. purpurea Makino showed as high contaminated by WHO's Microbial Contamination Limit standard. In case of Yukjin medicine in the Theory of Herb Medicinal Properties, total bacterial contamination rate showed as 17.7%, total fungal contamination rate showed as 41.2% and total aerobic mircobial count and total fungi count on Ephedra sinica Stapf. Pinellia ternate Breitenbach, Evodia officinalis Dode showed as high measured. The microbial conatmination rate materials which make up Yukmijihwanghwan were mostly high therefore the total aerobic microbial count was measured as high in case of Yukmijihwanghwan, the characteristics about microbial contamination strain is to be researched. Conclusions : By combining the basic data and experimental results related to microbial contamination of herb medicine, the most ideal storage standards for herb medicine has been attempted to be presented.

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.215-221
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• 2015

Chicken breast meat samples were injected with marinade solution (salt, sugar, phosphate, monosodium glutamate, and nucleic acid) with or without 2% citrus peel extract (CPE), and then a subset were irradiated with a 1 or 2 kGy electron beam (EB) and/or subjected to high-pressure (HP) at 300 or 400 MPa. The initial total aerobic bacterial (TAB) count of the control sample was 4.57 log CFU/g and reached 7.17 log CFU/g after 3 days of storage at $4^{\circ}C$. The 2 kGy EB reduced the TAB count to 4.61 log CFU/g after 7 days. The 400 MPa HP treatment was also effective in reducing the TAB count, but the effect was slightly less than that noted with the 2 kGy EB. The CPE, in combination with the EB and HP, decreased the TAB count by 1.71 and 1.32 log CFU/g at the initial stage and further decreased the count during storage. The 2 kGy EB and the HP (300 and 400 MPa) increased the thiobarbituric acid-reactive substances value, whereas the CPE did not show an antioxidative effect. The EB and HP caused no difference in the sensory qualities. In contrast, the CPE decreased all sensory qualities tested. Sensory panelists commented that the samples with CPE were not in the "rejection" category but were "unfamiliar" for chicken breast meat. In conclusion, the EB was more effective than HP in improving the microbial quality of marinated chicken breast meat. The use of CPE in the marinade solution may synergistically increase the shelf life; however, it is necessary to develop an appropriate formulation to ensure that the sensory qualities are maintained.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.118-125
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• 2008

Diverse organic amendments available in local areas have been used to improve soil quality in red pepper field and so the need for investigating the soil chemical and biological properties changed by the organic amendments application is increasing. Soil microbial diversities were measured by phospholipid fatty acid (PLFA) and Biolog $EcoPlate^{TM}$. Compost was most effective for improving soil chemical properties including pH, EC, total nitrogen, P, K, and Ca, and bark increased soil organic matter significantly (P=0.05). Compost increased the fatty acids indicating actinomycetes and vascular arbuscular fungi, and ratio of cy19:0/18:1w7c and monounsaturated fatty acids/saturated fatty acids in soils in PLFA analysis. Bark increased soil fungal indicators in PLFA analysis (P=0.05). Principal component analysis of Biolog EcoPlate data and PLFA differentiated the compost- and bark-amended soils from other organic matteramended soils especially the soil incorporated with compost. More researches are needed to use bark for improving soil microbial properties because the soil chemical and microbiological properties caused by compost and bark are significantly different.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.437-444
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• 2016

Rapid and reliable identification of microorganisms is important to maintain food quality and to control safety. MALDI-TOF MS-based identification methods are relatively fast and simple compared to other conventional methods including gram staining and biochemical characterization. A colony on subcultured media can be directly prepared on the analysis plate without further complex treatments. In this study, we confirmed the applicability of MALDI-TOF MS-based identification of foodborne pathogens such as Salmonella Enteritidis/Typhimurium, Staphylococcus aureus, Vibrio parahaemolyticus, Clostridium perfringens, Listeria monocytogenes, Yersinia enterocolitica, Bacillus cereus, Campylobacter jejuni, Campylobacter coli, and Cronobacter sakazakii on the Korea Food Standard Codex. MALDI-TOF MS data of the pathogenic reference strains were incorporated into a commercial MicroID (ASTA Inc.) database. Other pathogenic reference strains and seven isolates from various food samples were correctly identified to the species level by using the MicroID database. In conclusion, MALDI-TOF MS is comparable with commercial biochemical identification.

• Journal of Food Hygiene and Safety
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• v.3 no.4
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• pp.233-239
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• 1988

Vegetable mixed codiments, commercial products prepared using soybean,paste and natto, respectively as the ingredients, were used ina study to evaluate the efficacy of gamma irradiationas a means of decontamination and the emphasis was placed upon the determination of the effect of irradiation on the microbiological and some physicochemical properties of the samples. The number of microorganisms contaminated ranged from $10^{6}\;to\;10^{7}$ cells per gram in mesophilic total bacteria, which were composed of thermophilts and acid tolerant bacteria by over 90%. They were reduced by 3 to 4 log cycles with irradiation at 10 kGy. Gamma irradiation at 5 kGy could eliminate the microbial populations of yeasts and molds ($10^{2}\;to\;10^{3}$ cells per gram) and coliforms ($10^{6}\;to\;10^{6}$ cells per gram of natto condiments). However, total destruction of microorganisms in soybean-paste and natto condiments was shown to be possible at a dose-range more than 10 kGy. Irradiationup to 10 kGy was not detrimental to the physicochemical properties of the sample, such as pH. amino nitrogen, rancidity and color, even though some change was brought about in the content of sulfur-containing amino acids.