• Journal of Environmental Science International
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• v.17 no.7
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• pp.817-826
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• 2008

Using high voltage electric fields induced by high voltage AC (10-12 kV/cm, 20 kHz) and pulsed (20-30 kV/cm, 40 Hz) electric field generator as a semipermanent and environment-friendly disinfecting apparatus, the disinfection effect of coliform group in the effluent of sewage plant was investigated. The effects of electric field strength, treatment time, discharge area of a discharge tube, water quality factors (electric conductivity, pH and SS) on its death rate were examined. The death rate of coliform group was increased with increasing electric field strength and treatment time. For AC and pulsed electric field generator, the critical electric field strength was 6 kV/cm and 2 kV/cm, respectively, and the critical treatment time was 5 min and 2 min, respectively, regardless of electric field strength. Comparing the death rate of coliform group by AC and pulsed electric fields used in this study, its death rate was higher for the latter than the former, but did not increase linearly with increasing electric field strength. The results obtained for the effects of discharge area, electric conductivity, pH and SS on the death rate of coliform group using AC electric field (12 kV/cm, 20 kHz) were as follows: its death rate showed the trend to increase linearly with increasing discharge area; for the effect of electric conductivity, its death rate was increased with increasing electric conductivity, regardless of ionic species, increased with increasing cationic valency, but was similar between the same cationic valency; the pH $5{\sim}9$ used in this study did not affect its death rate; its death rate was decreased with increasing SS concentration.

• Journal of The Korean Society of Integrative Medicine
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• v.4 no.4
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• pp.109-117
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• 2016

Purpose : This study was designed to provide basic data of effective sanitization method of sprout vegetable for microbiological safety. Methods : Sanitization treatments were performed by dipping the sprout into chlorine and vinegar water. Microbial analysis were composed of the total plate count(TPC) and coliform group count(CGC). Result : Among chlorine water sanitization, the microbial reduction was largest in 100ppm chlorine water, and its TPC and coliform group count decreased to 6.01 log CFU/g and 5.06 log CFU/g. The effective dipping time in 100ppm chlorine water treatment was 5.97 log CFU/g and 5.91 log CFU/g for 30min and 60min, in which TPC were below the microbiological safety limits of 6.00 log CFU/g. Coliform group counts were decreased to 5.44, 5.46, 5.42 log CFU/g in the dipping the spouts for 30min, 60min and 90min. As a result of sanitizing alfalfa spout by vinegar water, a microbial counts tended to decrease with increasing concentration and the dipping time. The effective concentration of vinegar water was 2% for TPC(6.00 log CFU/g) and 1% for coliform group count(5.20 log CFU/g). With 1% vinegar water treatment, TPC became below the microbiological safety limits in all samples and in particular, the sample treated for 60min and 90min(4.93, 4.54 log CFU/g). While coliform group counts were decreased to 3.91 log CFU/g in the dipping the sprouts for 90min, those were still beyond the permitted limit. Conclusion : To secure the food safety of food service facilities including kindergarten feeding, it is considered that along with the systematic study of effective disinfection method for microbiological control at the preconditioning level of spout vegetable within the range of secured maleficence to human body, and the study regarding the measures to lower the initial microbiological pollution of spout vegetable.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.217-221
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• 1975

This study was carried out to evaluate the sanitary quality of Jarhi-dom, Chromis notatus, and its products, during the period from May to October, 1975. And bacterial density of the sea water in the estuary of Sogwipo was compared. The number of general bacteria and coliform group in the sea water appeared lower than that of other areas. Both Jarhimuchim-hoe and Jarhimul-hoe showed higher bacterial densities than the fresh fish when caught and sold in the market although Jarhimuchim-hoe showed slightly higher density than Jarhimul-hoe. Vibrio parahaemolyticus was detected in some samples of sea water and Jarhi-dom, but it was not regarded for food poisoning. Bacterial densities in total plate counts, coliform group and Vibrio parahaemolyticus was highest in August and September.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.1045-1051
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• 2021

Eighty-nine different types of commercially salt-fermented fishery products comprising various raw materials were analyzed for total aerobic bacteria, number of coliform bacteria, fecal coliform, and Escherichia coli. The food-poisoning bacterial content of the samples was investigated using next-generation sequencing. The mean mass of total aerobic bacteria in Jeotgal was 6-1.8×10⁹ CFU/g, and that in Aekjeot and Sikhae was 4-2.2×10⁵ CFU/mL and 1.9×10⁵-8.4×10⁸ CFU/g, respectively. Coliform bacteria were detected in 9 (28.1%) of 32 Jeotgal samples; 15 (46.8%) of 32 seasonal Jeotgal samples; and in 5 (55.5%) of 9 Sikhae samples. Fecal coliform and E. coli were not detected in 86 of the 89 samples. Yersinia enterocolitica was detected only in Galchi jeot (salt-fermented hairtail) (1 type) and not in other Jeotgal samples. These results contribute to our knowledge regarding the bacterial stability of salt-fermented fishery products.

• Journal of Ecology and Environment
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• v.48 no.1
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• pp.110-119
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• 2024

Background: The Mae Kha Canal is one of Chiang Mai's most important waterways. It supports local agriculture, irrigation, and transportation as well as provides stormwater drainage to prevent floods. Due to the unregulated rapid urbanization of the city and lack of efficient waste and wastewater management systems over the past few decades, the canal has become heavily polluted. This study aimed to evaluate the water quality of Mae Kha canal through assessment of the physico-chemical water quality and coliform bacteria. Moreover, benthic macroinvertebrates were samples and assessed using the Biological Monitoring Working Party (BMWP^Thai) and Average Score Per Taxon (ASPT^Thai) as biological indices. Results: The physico-chemical showed low dissolved oxygen levels, high levels of ammonia and phosphates, and elevated levels of biochemical oxygen demand, indicating that the water quality had significantly deteriorated. The canal was found to be heavily polluted, with most sites falling into the polluted to very heavily polluted. Coliform bacteria analysis revealed alarmingly high levels of total coliform bacteria and fecal coliform bacteria in the canal. The BMWP^Thai and ASPT^Thai scores indicated poor to very poor water quality. Conclusions: The physico-chemical and coliform bacteria indicated that the water quality of the Mae Kha canal had significantly deteriorated. The biological indices also indicated the poor to very poor water quality. This study underscores the urgent need for comprehensive remediation efforts, emphasizing strategic planning, investment, and community engagement to revive the canal's ecological health and water quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.429-436
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• 1998

A bacteriological study of sea water and oyster in Charan Bay was conducted to evaluate sanitary conditions of the bay and compliance of waters with the recommended bacteriological criteria for the designated area of shellfish cultivation, The Samples were collected at 23 sampling stations(Fig. 1 and Fig. 2) estaslished once a month from January 1997 to December 1997, During the study period, temperature ranged from 4.7 to $25.6^{\circ}C$, transparency ranged from 3.3 to 6.2m chemical oxygen demand ranged from 1.67 to 2.18 mg/$\ell$, dissolved oxygen demand ranged from 5.4 to 10.0 mg/$\ell$ dissolved nitrogen ranged from 1.65 to 7.88 $\mu$g-at/$\ell$, phosphate ranged from 0.15 to 1.16 $\mu$g-at/$\ell$, Chlorophylla-a ranged from 0.95 to 12.69mg/$\ell$. The coliform group and fecal coliform MPN's of sea water were ranged from <1.8$\~$l,600 and <1.8$\~$540, respectively. The coliform group and fecal coliform MPN's of oysters were ranged from <18$\~$16,000 and <18$\~$1,400, respectively. The viable cell counts in oyster ranged from $1.5\times10^2$ to $7.5\times10^3$. The bacteriological criteria of sea water in shellfish growing area should be less than 70 per 100 ml of sea water for median value of coliform MPN, and below $10\%$ of the samples which contain over than 230 for coliform MPN or over than 43 for fecal coliform MPN. The sea water from 432 samples were complied water coliform criteria recommended for designated shellfish growing area. The coliform group, fecal coliform, classification of coliform group with IMViC reactions and pathogenic vibrios were analyzed. During the study period, infectious bacteria such as Vibrio cholerae, Salmonella sp, and Shigella sp, were not detected from the samples, but detection ratios of Vibrio parahaemolyticus and Vibrio vulnifirus were $7\~17\%$ in summer months.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.1
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• pp.31-36
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• 1983

This experiment was carried out to evaluate the sanitary quality of ground water in Pusan area(see Fig. 1). One hundred and thirty two water samples were collected from the 11 stations from October 1981 to Sept ember 1982. To evaluate the sanitary quality, coliform group, fecal coliform, viable cell count and composition of coliform group by IMViC reaction were observed. The median value of coliform group MPN of the samples were 59/100 ml in Udong and Daesindong, 68/100 ml in Suyeong, Yeonsandong and Sungjigog, 43/100 ml in Jenpodong and Mangmidong, 33/100 ml in Yeongdo and Dongrae, and 13.3/100 ml in Gammandong. Geometric mean of fecal coliform MPM was 4.1/100ml in Udong, 8.6/100 ml in Suyeong, 8.1/100 ml in Jenpodong, 6.1/100 ml in Daesindong and Dongrae, 8.7/100 ml in Yeongdo, 7.1/100 ml in Mangmidong, 6.5/100 ml in Yeonsandong, 9.1/100 ml in Sungjigog, 3.0/100 ml in Gammandong and 7.6/100 ml in Gupo. The seasonal difference of total coliform showed much more contamination in June or July when there were more climers than in December though it was caused by the rise of loafer temperature. With 50 percentile of total coliform MPN July was about 30 times higher than December for July was 163.5/100 ml and December 5.3/100 ml, Particularly, June was about 1.3 times higher than July in contamination because of a sudden increase of people using it. Composition of coliform was $7.64\%$ Escherichia coli, group, $42.86\%$ Citrobacter freundii group, $16.78\%$ Klebsiella aerogenes group and $32.72\%$ others. Plate count of samples was varied from 48 to $4.4{\times10}^2/ml$ during the study period.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.95-102
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• 2006

To evaluate bacteriological water quality of groundwater in Yeungnam Province, samples were taken from 123 locations during summer and 117 locations during winter. The medians of heterotrophic plate counts.(HPCs) were 30 CFU/mL for the summer samples and 40 CFU/ml for the winter, and more than 25% showed HPCs higher than 100 CFU/ml. Coliform bacteria were detected from 46% of the summer samples and 30% of the winter. In these coliform-positive samples, the medians of coliform counts were 20 CFU/ml for the summer samples and 4 CFU/ml for the winter. Genera such as Citrobacter, Enterobacter, Escherichia, Klebsielia, Pantoea, Rahnellia, and Serratia were identified from the coliform isolates; among them, 48% were members of the genus Enterobacter. While E. cloacae, E. amnigenus, and K. pneumoniae were the most frequently isolated species, E. coli was isolated only from 1 location. The coliform counts were positively correlated with the HPCs, which also positively correlated with water temperature. The results of present study provide further insight on the extent of groundwater contamination with coliform bacteria.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.91-98
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• 2009

As consumption of kimchi has increased, factories have begun to produce this traditional Korean fermented vegetable dish on a large scale. Following the rise in manufacturing, the hygienic conditions under which commercial kimchi is being made have become an issue. We isolated 17 coliform bacteria from commercial kimchi that had not been fully fermented. These bacteria were partially identified as one of seven different species from three genera by 16S rDNA sequence analysis as follows: Enterobacter intermedius, Ent. cloacae, Ent. amnigenus, Klebsiella terrigena, K. ornithinolytica, K. oxytoca, and Hafnia alvei. Lactobacillus paraplantarum KNUC25 has been isolated from over-fermented Chinese cabbage kimchi and its antimicrobial activity reported in the literature. In our study, the KNUC25 strain showed antibacterial activity against isolated coliform bacteria and some pathogenic coliform bacteria through spot-on-the-lawn tests and viable cell tests. Through development and use of a cell-free supernatant of L. paraplantarum KNUC25, we effectively controlled coliform bacteria in commercial kimchi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.19-26
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• 1979

To evaluate the sanitary conditions of four species of commercial shellfish (Crassostrea gigas, Tapes japonica, Mytilus coruscus and Anadara granosa), the psychrotrophic coliforms and the bacterial flora were monthly examined from January to December, 1978. Viable cell counts of the samples submitted were $1.3\times10^3\~2.5\times10^6/g$ and the numbers of coliform and E. coli were above $0\~5.5\times10^2/g\;and\;2\~9.2\times10^2/100g$ respectively. Among the 373 coliform bacteria isolated from the samples submitted, 298 strains were identified as coliform by IMViC test, $44^{\circ}C$ culture and gelatin liquefaction test. E. coli type I and K. aerogenes type I were the most predominant ones among the identified coliform as 138 strains and 71 strains respectively. The psychrotrophic coliform growing at $5^{\circ}C$ were 186 $strains(50\%)$ among 373 strains of isolated coliform. Vibrio and Pseudomonas were the most predominant groups. Among 453 strains of isolated bacteria, Vibrio was 240 $strains(53\%)$ and Pseudomonas was 91 $strains(20\%)$. Moraxella, Acinetobacter, Enterobacteriaceae and Flavobacterium-Cytophage were scantly detected. In seasonal variation of general bacterial flora, a lot of Vibrio appeared from May to October, did Moraxella during the winter season and the other genuses showed no seasonal change.