• Journal of Environmental Health Sciences
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• v.2 no.1
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• pp.21-24
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• 1975

During April and May, 1973 rain water samples were collected five different times in nine selected areas of Seoul city. The pH factor and bacteria counts were measured. The following results were obtained. 1. The lowest pH was 6.18 at Moon Rae Dong and the highest was 6.30 at Jong Am Dong. This difference is not significant at the 0. 05 level. 2. The pH factor did not vary significantly with the time of sample collection. 3. Dae Bang Dong had the highest Total Plate Count of $1.9\times 10^3/ml$, Bo Moon Dong and An Kook Dong had the lowest Total Plate Count at $4.1\times 10^2/ml$. 4. The total plate count varied greatly according to the time of sample collection. This result can be used to remove are pollutants. 5. The Total plate Count is nearly inversely proportional to the length of time during which the sample is collected.

• Food Science of Animal Resources
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• v.18 no.1
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• pp.27-34
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• 1998

This study was carried out to evaluate of the microbial and sensory quality of ready-made hamburger and sandwich. Initial total plate count of hamburger for establishment A and B were 1.2$\times$102 cfu / g and 3.4$\times$102 cfu / g, respectively, and for establishment C was 7.9$\times$104 cfu / g. After 48 hour storage at 1$0^{\circ}C$, total plate count of hamburger for establishment A and B increased to 1.2$\times$104 cfu / g and 6.8$\times$103, respectively, and for establishment C increased to 1.2$\times$107 cfu / g. Initial total plate count of sandwich for establishment A and B were 3.2$\times$102 cfu / g 7.9$\times$102 cfu / g, respectively, and for establishment C was 1.1$\times$105 cfu / g. After 48 hour storage at 1$0^{\circ}C$, total plate count of hamburger for establishment A and B increased to 8.1$\times$103 cfu / g and 2.3$\times$104, respectively, and for establishment C increased to 4.4$\times$108 cfu / g. No E. coli, Salmonella, Vibrio, and Staphylococcus aureus were detected under simulated storage conditions. There was no significant changes in pH, acid value, and volatile nitrogen number under simulated conditions. In sensory evaluation of hamburger and sandwich, sensory score was lowered by increase of total plate count.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.422-427
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• 2007

The purposes of this study were to investigate the concentration of total coliforms in sewage effluents during the period from August 2004 to October 2005. The removal efficiency range of multi-tube method and plate count method were $31.3{\sim}99.5%$ and $66.8{\sim}99.2%$, respectively. Though a correlation between the multi-tube method and the plate count method in the same sample is low, not only is an experimental procedure very simple, but the time required also is short. The seasonal correlation between methods showed more sensitive spring and summer than autumn and winter. So the study indicated plate count method can be used in rapid and reliance identification of total coliform more than the multi-tube method.

• Journal of Food Hygiene and Safety
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• v.17 no.2
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• pp.55-60
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• 2002

In order to investigate the microbiological contamination of spring water, we performed the standard plate count, coliform and psychrotrophilic bacteria in 109 spring waters in Seoul. Of 109 spring waters, geometirc mean standard plate count was 0.19 CFU/ml, and the highest in Mt. Boolam, 4..43 CFU/ml and Mt. Dobong, 3.86 CFU/ml, but not detected in Mt. Woomyun and Mt. Cheonggye. Four spring waters have shown over 100 CFU/ml in standard plate count. The geometric mean psychrotrophilic bacteria was 49.2 CFU/ml, the most prevalent spring water was Mt. Nam, 125 CFU/ml, the lowest Mt. Woomyeun. Among a total of 109, coliform was detected from 21 spring waters(19.3%) and the geometric mean of coliform was 0.005 MPN/100ml. The isolated genera of coliform were 7 isolates of E. coli(33%), 5 Klebsiella(24%), 4 Enterobacter(19%), 3 Citrobacter(14%) and 2 Serratia(10%), respectively. The 22 spring waters(20.2%) failed to meet the standard limits of drinking water based on regulation in Korea. The inappropriate rate of standard plate count in spring water was 4.5%, that of coliform was 81.1% and both of them was 13.6%. There was the significant correlation between standard plate count and psychrotrophilic bacteria in spring water(r=0.95, p<0.01).

• Journal of Environmental Health Sciences
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• v.42 no.2
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• pp.126-132
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• 2016

Objectives: This study aims to provide basic data regarding the bacterial total plate count in the atmospheric environment for related studies. Methods: Total plate count and the identification of culturable bacteria in the atmospheric environment in Incheon took place in 2015 using periodic survey. Correlationship analysis was performed between the number of culturable bacteria and environmental elements. In addition, an estimation of novel bacterial species was undertaken using the similarities and phylogenetic tree based on the 16S rRNA gene. Results: The total plate count of culturable bacteria was on average $176CFU/m^3$, and did not exceed $610CFU/m^3$ in the atmospheric environment. Periodic monthly measuring of total plate count was highest in June at $293CFU/m^3$, while the lowest was in July at $125CFU/m^3$. Furthermore, as a result of the identification of culturable bacteria, the genera Arthrobacter and Kocuria were dominant, while novel bacterial taxa that belong to the genera Chryseobacterium and Herbiconiux were separated. Conclusion: The total number of culturable bacteria from the atmospheric environment in Korea is on average $176CFU/m^3$. In addition, the genera Arthrobacter and Kocuria dominate. The presence of novel bacterial taxa are expected in the atmospheric environment, such as belonging to the genera Chryseobacterium and Herbiconiux.

• Journal of Environmental Health Sciences
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• v.36 no.2
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• pp.141-147
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• 2010

Indicator bacteria of fecal pollution were enumerated and compared by various detection methods for influent and final effluent of a sewage treatment plant. Total coliforms were enumerated by four methods including most probable numbers, chromogenic enzyme substrate test, membrane filtration, and plate counts and were about $10^4$ for influent and $10^2{\sim}10^3\;CFU/ml$ for final effluent. Fecal coliforms ranged between $10^3$ and $10^4$ for influent and $10^2\;CFU/ml$ for effluent by chromogenic enzyme substrate test and membrane filtration. Fecal streptococci counts were 1-log less than fecal coliforms counts, $10^2{\sim}10^3$ for influent and $10^1\;CFU/ml$ for effluent. Total coliforms numbers by plate count both in influent and in effluent showed 1-log higher than by the other three methods. Statistical analysis revealed that numbers of total coliforms by plate count in final effluent had the highest average of correlation (r=0.778, p<0.01) compared with those by the other three methods. In addition, total coliforms numbers by plate count showed most significant correlation (r=0.835, p<0.01) with those by chromogenic test which is well-known as its highest recovery efficiency. These results suggest that the plate count would be the optimum detection method for total coliforms in wastewater treatment plants which are the only microbiological standard of final effluent from wastewater treatment plants in the Republic of Korea, considering economic aspects and difficulties in laboratories.

• Journal of Food Hygiene and Safety
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• v.19 no.4
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• pp.209-216
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• 2004

Dry rehydratable film methods were compared to conventional methods for the enumeration of microorganisms in Korean traditional foods. Kimchi, doenjang, kochujang, kanjang, takju, sujeongkwa and sikhe were used as Korean traditional foods. $Petrifilm^{TM}$ aerobic count plate, $Petrifilm^{TM}$ coliform count plate, $Petrifilm^{TM}$ E. coli/coliform count plate, $Petrifilm^{TM}$ yeast and mold count plate and $Petrifilm^{TM}$ staph express count plate were compared to plate count agar, most probable number (MPN) for coliform, MPN for E. coli, potato dextrose agar and coagulase test, respectively. Regression analysis indicated that correlation coefficient values were 0.974-0.998, 0.913-0.995, 0.955-0.978, 0.968-0.986 and 0.998-0.999 for total aerobic bacteria, yeast and mold, coliform, E. coli and S. aureus, respectively. There were no significant differences between two methods, suggesting that $Petrifilm^{TM}$ plates can be used as an alternative to conventional method for the determination of microorganisms in Korean traditional foods.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.764-769
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• 1994

This study was performed to obtain fast, consistant and reliable estimation system of bacterial counts of raw milk, which effectively related to the quality of sanitaion and the condition of production at the farm. This study compared regression equation and correlation coefficient relationship between standard plate counts and data of Malthus conductance method for the detection time of total, psychrotrophs, coliform bacterial counts in raw milk. Regression equation (RE) between conductance detection time (Y) and total bacterial log counts (X) was Y=18.27651 - 2.07550X, with correlation coefficient -0.95(n=201). In coliform, RE was Y=9.320848 - 1.15598X with correlation coefficient -0.90 (n=207). Psychrotrophs had the RE of Y=29.96008-3.02487 with correlation coeffecient -0.9 (n=201). This conductance method gave results more quickly and was less labor-intensive than traditional standard plate count method.

• Journal of Korean Society on Water Environment
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• v.40 no.4
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• pp.161-167
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• 2024

The demand for bottled water in South Korea is steadily increasing, but there are challenges regarding water sources and violations of water quality standards. Consumers struggle to identify products that do not meet these standards, highlighting the need for improved water management. This study aims to investigate the use of flow cytometry to identify microbial behavior in bottled water. Twelve different bottled water brands were selected for this study. A novel non-culture-based analysis method called total cell count via flow cytometry was utilized, which is not commonly used to assess drinking water quality. This method was compared to conventional culture-based methods for heterotrophic plate count and E. coli experiments, in order to introduce new indicators for hygiene management. Adenosine triphosphate analysis was also conducted to assess cell activity, and total organic carbon was measured to determine the presence of organic matter. The total cell counts varied among the different bottled water brands. The adenosine triphosphate levels ranged from 37.1ng/L to 221.7ng/L, while the total organic carbon ranged from 0.4 to 0.6 mg/L. Furthermore, E. coli was not detected in any of the bottled waters, and with the exception of two cases, the levels of heterotrophic bacteria did not exceed the drinking water standard of 100 CFU/mL. This study demonstrated a correlation between total cell count and heterotrophic plate count, suggesting that non-culture-based analysis could be valuable in promptly assessing microbial contamination, in contrast to the conventional methods that require approximately 48 hours for incubation.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.4
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• pp.419-430
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• 2005

In this study, to prove the effect of soybeans's electron donating ability and its addition on eel gouem, storage and sensory characteristics were examined. During the storage period, pH values of all gouem samples were decreased with initial increase except the control. BSB $3\%$ sample had the lowest pH value and YSB $10\%$ sample was the highest 6.71 in pH value at first storage day. The electron donating ability of soybeans were increased with the amount of addition. The electron donating ability of SBSB 20g sample was the highest, which was 2 ${\~}$ 3 times higher than that of YSB sample. L values of all the gouem samples had a tendency to decrease according to the storage period and amount of addition. All samples' a values were increased throughout the storage period, while b values decreased except the control and GNG sample. TBA and VBN values of all the samples were up and down throughout the storage period SBSB $10\%$ sample had the lowest in TBA value. The electron donating ability of all soybean samples and TBA value of eel gouem samples showed a negative correlation. Total plate count of bacteria was increased rapidly for initial storage period, but all samples showed a tendency of slow growth after the 8th day of storage. During all storage days, SBSB, BSB samples had a similar tendency of low total plate count growth. GNG $10\%$ sample showed the lowest in total plate count of bacteria at sixteenth day of storage. Sensory scores of all samples decreased with storage. For all the items of the sensory evaluation, SBSB $5\%$ sample got the highest score among all eel gouem samples. GNGSB sample showed the lowest in TBA value and total plate count of bacteria. And in the sensory evaluation, GNGSB sample got the highest scores for several items.