• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.241-246
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• 2001

Distribution of pathogenic vibrios in the seawater of live fish tank and effect of environmental factors on their existence were investigated by collecting samples from fish markets and restaurants in 6 different cities. Pathogenic vibrios and coliforms were determined by using the most probable number (MPN) procedure, and aerobic plate count was enumerated by the standard pour plate method. No Vibrio chulerae O1 was detected in all the samples tested. Detection rates of V. cholerae non-O1, V. parahaemolyticus and V. vulnificus in all the smaples tested were 7.7%, 69.2% and 23.1%, respectively. Water temperature and trubidity of the seawater measured were higher in the pathogenic vibrios positive samples than in those negative samples. However, higher salinity and pH were shown in the pathogenic vibrios negative samples than in positive samples. The aerobic plate counts and MPN or total and focal coliforms in the seawater were higher in the presence of pathogenic vibrios than in the absence of pathogenic vibrios. In this study, the presence of pathogenic vibrios in the seawater tested was closely related with other physiochemical parameters and populations of coliforms, indicators far food safety.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.1-8
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• 2009

With the development of IT convergence technology and the construction of master plan for the four rivers restoration of the government, the importance of the eco-friendly water pollution management is being spotlighted. In this paper, we proposed the effective water pollution management using the reservoir tank automatic classification for improving the water quality and on-line managing efforts of ceo-friendly reservoir tanks. The proposed method defined the seven factors of water pollution evaluation and managed the water pollution according to hydrogen ion concentration(pH), chemical oxygen demand(COD), suspend solid(SS), dissolved oxygen(DO), count of coliform group(MPN), total phosphorus(T-P), and total nitrogen(T-N) using the sensors. We measured the values for the seven factors from the reservoir tank and normalized to ranging from 1 to 9. To evaluate the performance of the water pollution management using the reservoir tank automatic classification, we conducted F-measure so as to verify usefulness. This evaluation found that the difference of satisfaction by the traditional system was statistically meaningful.

• Journal of Korean Society on Water Environment
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• v.25 no.3
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• pp.363-369
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• 2009

We developed the Eco medium for Escherichia coli and total coliforms, which was modified by Violet Red Bile (VRB) medium, and derived the standard curve of exponential phase at $OD_{410}$ by using type strains such as E. coli ATCC11303, Enterobacter cloacae KCTC2361, Klebsiella pneumoniae KCTC2241, and Citrobacter freundii KCTC2359. Also, we used total 93 samples of spring and stream water to compare the detection ability of total coliforms between the method using Eco medium and such as most probable number (MPN), and plate count methods. As a result, the qualitative analysis of E. coli and total coliforms using Eco medium contained ortho-nitrophenyl-$\beta$-galactoside (ONPG) and 4-methylumbelliferyl-$\beta$-D-glucuronide (MUG) was same as those of Korean standard methods (Colilert kit). And the colony forming unit (CFU) detected in Eco medium was similar to those of result from MPN and plate count methods. Moreover, the agreement, sensitivity, and specificity of the developed kit was more than 97.5% in comparison with Colilert kit for 350 samples. Thus, the Eco medium can be used both qualitative and quantitative analysis of E. coli and total coliforms.

• Applied Biological Chemistry
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• v.33 no.2
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• pp.138-142
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• 1990

The effects of heavy metals Cd, Cu, Cr, Ni, and Zn on the degradation of the insecticide fenitrothion (O, O-dimethyl O-4-nitro-m-tolyl phosphorothioate), the fungicide IBP (5-benzyl O, O-diisopropyl phosphorothioate), and the herbicide butachlor (N-butoxymetyl-2-chloro-2', 6'-diethylacetanilide) in flooded soils were examined in the laboratory. The degradation of the 3 pesticides in soil was greatly inhibited by the amendment of the 5 heavy metals. The inhibition rate was high in the order of butachlor>IBP>fenitrothion. Populations of fenitrothion-and butachlor-degrading microbes, which were counted by the MPN method, were lower in heavy metals added soil than in the control soil. The effect of heavy metals on the degradation of the 3 pesticides in soil varied with the kind and concentration of heavy metals and the kind of pesticides.

• Korean Journal of Veterinary Service
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• v.20 no.2
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• pp.169-175
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• 1997

This study was carried out to assess the effect of the chlorine treatment into water for processing chicken products in each stage of slaughtering, with a special viewpoint related with reducing the viable number of microorganisms by which the water and the chicken body were contaminated. The mean bacterial number on chicken samples after picking process was log5.37$\pm$0.20~5.84$\pm$0.160CFU/$\textrm{cm}^2$. When assessed by standard plate count method, it was the higher one than any other processing stage in which eviscerating, pinning, packaging, and chilling was followed in order of the mean bacterial number. The coliform bacterial numbers on carcasses after sampling from different processing stages were log2.11$\pm$0.63~2.88$\pm$0.25MPN/$\textrm{cm}^2, which show almost similar numbers in each processing stage. But, after chilling process the number was decreased slightly. The bacterial counts in the water for scalding and chilling showed log3.43 $\pm$ 0.59~5.06$\pm$0.21 and log4.30$\pm$0.21~6.62$\pm$0.33CFU/$m\ell$, respectively. In the coliform counts for the water taken out from the 2nd chilling tank, the number was log1.97$\pm$0.35~2.91$\pm$0.22MPN/$m\ell$ which showed higher than those of the 1st and the 3rd chilling tank water. The effect of chlorination in reducing the bacterial numbers was accepted at the residual chlorine concentration of 1$m\ell$/$\ell$by showing the reduction from $10^8$ to $10^4$CFU level and the numbers were decreased less than 10CFU at the concentration of 5mg/$\ell$, when assessed by viable cell counts. In conclusion, these results suggested that chlorination In chilling water with final concentration of 5mg/$\ell$was strongly recommended to reduce the bacterial numbers on final chicken products.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.815-818
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• 2001

Indicator organisms are frequently used to monitor bacterial contamination of water. The most common indicator organisms used in water quality monitoring are coliforms and Escherichia coli. To develop a rapid and quantitative method for detecting the coliforms and E. coli in water, cell growth kinetics and defined substrate technology were applied in this study.

• Journal of Food Hygiene and Safety
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• v.32 no.4
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• pp.249-253
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• 2017

This study aimed to compare the automated most-probable-number (MPN) TEMPO BC and the quantitative mannitol-egg yolk-polymyxin (MYP) plate methods for enumeration of Bacillus cereus in food samples known to be frequently contaminated. Food products that were naturally or artificially contaminated with B. cereus were analyzed by both methods. A difference of less than 1 log (CFU/g) between the two methods was noted in 95.3% samples. There were no significant differences in artificially contaminated products between the two methods in terms of $R^2$ values for sauce products, jorim products, fish products, etc. However, a significant difference was noted for sunsik, fermented soybean products, and products. The linear equation of naturally versus artificially contaminated food was $log_{(TEMPO\;BC)}=0.8453{\times}log_{(MYP\;plate\;agar)}+0.1642$. Statistical analysis of the results showed good agreement between the two methods. Due to growing interest in food safety, the use of the TEMPO BC method may increase. In response to this trend, the results from this study will offer valuable comparative data on the feasibility of existing methods and help develop new approaches for food safety testing.

• Microbiology and Biotechnology Letters
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• v.24 no.3
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• pp.364-370
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• 1996

Sediments collected from the Jungnang-cheon and its tributaries were used to enumerate anaerobic bacteria by most probable number (MPN) methods. A simple method was developed to detect ferrous ion in the culture fluid in order to count the number of iron ion reducers, and sulfate-reducing bacteria (SRB) and methanogens were detected by the presence of FeS precipitate in the culture or methane in the head space, respectively. The numbers of iron reducer was in the range of 10$^{7}$ - 10$^{8}$ /g in the sediment of the stream containing higher organic content than the tributaries. The sediments of tributaries were analyzed to contain iron reducers less than 10$^{7}$ cells/g. With one exception the numbers of SRB and methanogens were less than 10$^{3}$ cells/g in the sediment. From these results it is concluded that organics in the sediment support the growth of iron reducers, which out-compete SRB and methanogens.

• Korean Journal of Hydrosciences
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• v.2
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• pp.115-126
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• 1991

The anaerobic digester with sludge from sewage treatment plant was operated in the laboratory for two year to investigate the enumeration and activity of methanogenic microorganisms. In this experimental study, the effects of HRT on the degradation characteristics of organic materials and on the number of methanogenic bacteria produced were investigated. By making the media with the repeated wxperiment, the number and activity of methanogenic bacteria were measured. The increase of the removal rate of organic acid in the digester was oberved at HRT of 2 days. The total number of methane forming bacteria estimated by the MPN method showed 2.3 $\times$ $ at HRT of 3 days, 7$\times$$ of 5 days and 7.9$\times$$ $/ml of 10 days. The optimum incubation time for measuring the number of methanogenic bacteria was found as more than four weeks. The PMA revealed 161ml CH$/l day at HRT of 10 days and the PUA 290mg COD/l day. At the incubation time 4.3 days, the maximum value of CH$ *59.1%) was found. At this time, $ was found as 15.3% and $ 25.6%.

• Journal of Animal Environmental Science
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• v.5 no.2
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• pp.123-132
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• 1999

This study was carried out to find deodorization management method of the efflux from swine slurry treated by thermophilic aerobic oxidation reactor. Three kinds of deodorization methods in Lab-scale reactors, were used in this experiment; No treatment, air injection treatment(50$m\ell$ air/min. $\ell$) and inoculumn of photrophic bacteria treatement(108 cell(Most probable number, MPN)/$m\ell$). The concentration of volatile fatty acids(VFAs), hydrogen sulfide(H2S), and ammonia(NH3) were analyzed during the treatment period(50 days). The major results obtained as follows. 1. Air injection method to efflux showed very high removal effect on malodorants such as VFAs, hydrogen sulfide(H2B). But ammonia(NH3) was emitted to much. 2. PTB inoculum method was also effective in removal of malodorants, VFAs, Hydrogen sulfide(H2S), when it was applied to the efflux. 3. We found that the concentrations of malodorants, VFAs, H2S, NH3 had some relatinships with the pH, ORP, BOD in the efflux.