The bacteriological examination of spring water in Seogwipo-city was conducted. A total 11 spring water samples were performed from January to April, 2010. During the study period, the range of temperature was from 0.7 to $15.4^{\circ}C$, and result of the analyses showed that hydrogen ion concentrations (pH) for spring water was 0.33 to 7.8. salinity levels for sample average of 0.5 to 1.04‰, as the result of measuring dissolved oxygen (DO) for spring water showed that water dissolved oxygen were 1.02 to 7.14 mg/${\ell}$. The range of total coliform of spring water sample at 11 stations located in the designated spring water were <1.8~>1,600 MPN/100mL. And the range of geometric mean of total coliform were 1.9~117.1 MPN/100mL, The range of fecal coliform of spring water sample at 11 stations located in the designated spring water were <1.8~>1,600 MPN/100mL. And the range of geometric mean of fecal coliform were 1.8~68.1 MPN/100mL, respectively. Level of microbial contamination was examined in 11 samples for indication of bacterial contamination such as heterophic bacteria, EscherichiacoliO157;H7, salmonella spp., Vibrio parahaemolyticus, Staphylococcus aureus, Shigella spp. Were frequently detected from the spring water. Salmonella spp., S.aureus were detected in the range of $0{\sim}1.0{\times}10^1$, $0{\sim}3.0{\times}10^1$ CFU/ml, respectively. And the Escherichia coli O157;H7, Vibrio parahaemolyticus, Shigella spp. Were not detected from the examined spring water samples.
The seawater in the Taean area was surveyed to evaluate the conditions of the bay and compliance with the bacteriological criteria for a designated area for shellfish production for export. Samples of seawater were collected monthly at 34 sampling stations established in the survey area from January 2002 to December 2004. The bacterial density in the coastal area close to a pollution source located to the northeast of the survey area was higher than in the open sea to the west. The bacteriological counts in the water did not change with 16.5mm of rainfall, but increased abruptly after 65.4mm of rainfall. The total coliform and fecal coliform most probable numbers (MPNs) of 1,224 seawater samples in the survey area were <1.8-2,400 and <1.8-790 MPN/100 mL, respectively. The geometric mean and estimated 90th percentile of total coliforms were 1.9-3.4 and 2.7-26.3 MPN/100mL, respectively, and for fecal coliforms were <1.8-2.6 and 1.8-12.0 MPN/100mL, respectively. The bacteriological water quality in the Taean seawater area met the National Shellfish Sanitation Program criteria for an approved area and the Korea Shellfish Sanitation Program criteria for a designated area for shellfish production for export.
Naengmyon is a Korean buckwheat noodle with chilld broth, and the juice of dongchimi, a Korean radish pickle fermented with wild lactic acid bacteria, has been used as the broth for naengmyon traditionally. The purpose of this study was to demonstrate the inhibitory effect of dongchimi-juice against coliform bacteria in model system of naengmyon-broth. Dongchimi-juice was made from radish juice by the cultivation of lactic acid bacteria which had been isolated from kimchi. Three types of naengmyon-broth, beef-broth type, dongchimi-juice type and the mixed type, were made as model systems, and then the changes in viable cell counts of seven coliform bacteria, Klebsiella planticola Bo2, X. terrigena CO8, K. pneumoniae DOI, K. ozaenae DO4, Enterobacter sp. AO2, Enterobacter sp. CO7, Citrobacter sp. BO7 and Escherichia sp. DO3, which had been added to each type of naengmyon-broth in advance, were investigated during storage at 3$0^{\circ}C$ All coliforms grew rapidly in naengmyon-broth of beef-broth type, while none grew in dongchimi-juice type or in the mixed type. All coliforms died out far more rapidly in dongchimi-juice type than in mixed type. The decreasing slopes of Citrobacter sp. Bo7, K. planticola BO2, X. terrigena CO8 and K. ozaenae DO4 were more steep than those of the rest. It was thought that the preparation method of Korean traditional naengmyon such as dongchimi-naengmyon or Pyongyang style-naengmyon, which uses oxy dongchimi-) juice or the mixture of dongchimi-juice and beef-broth, would be very effective for preventing the growth of coliform bacteria from naengmyon.
This investigation was carried out to evaluate the removal effect of biological contaminants for the municipal sewage treatment process at Cheonggye Cheon terminal plant which in the first plant for municipal sewage treatment in Seoul area. It was conducted in raw influent, primary treatment water and secondary treatment water from September, 1986 to July, 1987. The results were as follow; 1, The primary treatment could eliminate microbials for $65.38\%$ of total bacteria, $64.35\%$ of total coliform, $62.16\%$ of fecal coliform $69.48\%$ of pseudomonas and $64.70\%$ of fecal streptococci in averages for a year respectively. 2. The secondary treatment could eliminate microbials for $97.50\%$ of total bacteria, $97.30\%$of total coliform, $95.95\%$ of fecal coliform, $97.00\%$ of pseudomonas and $96.53\%$ of fecal streptococci in average for a year respectively. 3. In the detect rate of pathogenic agent, salmonella spp was decreased $12.5\%$ to $4.2\%$ in primary treatment and it was not detected in secondary treatment, shigella spp was detected $4.2\%$ in influent water but it was not detected in primary and secondary treatment. 4. In the seasonal variation of treatment effect, the removal of summer was the highest, and the removal of all item in winter was lower than the other seasons. 5. There was significant correlation between water temperature and microbal all items (P<0.05) $NH_3-N$ and Microbal items (P< 0.01) at raw water.
In order to investigate the hygienic conditions of potable water in farm area, we examined the hygienic bacteriological and chemical tests of the 159 waters in the farm areas of Kwangjugun, Namyangju-gun, Yangpyung-gun Paju-gun and Hwasung-gun.The results were as follows: 1. Of the 159 waters, the average numbers of standard plate count and coliform were 920 $\pm$ 250ml and 450 $\pm$ 380/100 ml, respectively. The average pH was 6.74 $\pm$ 0.08, KMnO$_4$ consumption 4.18 $\pm$ 0.23 mg/l, turbidity 0.74 $\pm$ 0.08 degree, NH$_3$-N 0.07 $\pm$ 0.02 mg/l, NO$_3$-N 7.76 $\pm$ 0.48 mg/l, total hardness 101.3 $\pm$ 4.7mg/l, chlorine 18.6 $\pm$ 1.3mg/l, sulfate 12.9 $\pm$ 1.0 mg/l, lead 0.036 $\pm$ 0.003 mg/l, manganese 0.017 $\pm$ 0.003 mg/l, zinc 0.064 $\pm$ 0.005 mg/l, and copper 0.010 $\pm$ 0.001 mg/l, respectively. 2. Of the 159 waters, 84 samples (52.8%) were over 100 per ml of SPC or detected coliform per 100 ml water and 63 samples (39.6%) exceed over physicochemical limited criteria for potable water. NO$_3$-N was the primary item among excess contents of potable water in farm areas. 3. The contents of total hardness, chlorine and NO$_3$-N in Hwasung-gun were higher than those in the other regions, but the numbers of SPC and coliform in Yangpyung-gun and Namyangjugun were higher than those in the other regions. 4. The correlationships among many items were highly significant (SPC, Coliform, KMnO$_4$ consumption NH$_4$-N, NO$_3$-N, KMnO$_4$, Total hardness, Chlorine, Sulfate).
To evaluate the quality of drinking water and contamination sources in a rural community, this study was carried out on the summer of 2003 at Shin-Dong Myun, Chun-Cheon, Gang-Won province. Seventy three drinking water samples were collected from three different types of water supply systems. Sources of contamination were identified and the public perception of water quality area were evaluated. The findings of this study are as follows; Drinking water was mainly obtained from Local Water and Simple Piped Water Supply Systems, and pollution sources varied over the study area. Most of residents (>63%) were satisfied with the quality of drinking water and could not identify any contamination sources. Corresponding to this perception, measured water quality parameters generally met the Drinking Water Quality Standards (>64%). However, approximately 35.6% of samples exceeded the regulation for Nㅒ$_3$$^{-}$$_{-}$N, coliform, and general bacteria. The water quality was significantly different among the three water supply systems, and between the potentially contaminated areas and the rest of the areas (p<0.05). In the potentially contaminated areas, the levels of coliform and general bacteria contamination were significantly higher than the rest of the areas (p<0.05). The coliform and general bacteria values of Simple Piped Water were significantly higher than Own Piped Water's, and the NO$_3$$^{-}$$_{-}$N values of Own Piped Water were significantly higher than those of water's (p<0.05). Based on this study, NO$_3$$^{-}$$_{-}$N, coliform, and general bacteria were identified as a major problem of drinking water. To regularly manage drinking water supply systems, to identify contamination sources, and to add drainage systems are required in the study area.
Dehghani, Rouhullah;Miranzadeh, Mohammad Bagher;Tehrani, Ashraf Mazaheri;Akbari, Hossein;Iranshahi, Leila;Zeraatkar, Abbas
Membrane and Water Treatment
/
v.9
no.4
/
pp.273-278
/
2018
Due to the lack of water in arid and semi-arid areas, reuse of wastewater can be a suitable way to compensate for water scarcity. Therefore, in this research, evaluation of the quality of wastewater of Kashan Treatment Plant to use for irrigation was studied. This descriptive cross-sectional study was conducted in 2016. pH, TSS, TDS, turbidity, COD, BOD5, Total Kjeldahl Nitrogen, Total Phosphorus, Total Coliform, fecal coliform, nematode eggs of inlet and outlet of wastewater treatment plant in Kashan were studied. Mean and standard deviation and wastewater quality parameters before and after treatment were tested with SPSS 22 (2014) software. The mean wastewater output of COD, BOD5, TSS, TDS and turbidity were respectively 86.6, 41.2, 11.11, 1095 mgL-1 and 17.5 NTU and the pH was equal to 7.22. Also, the average of Total Kjeldahl Nitrogen and phosphorus were 22.4 and 2.2 mgL-1 respectively. The mean of Total Coliform and fecal coliform were 225, 161 MPN / 100 ml respectively. In addition, no nematode eggs were found in final effluent. The results indicated that the treatment plants had a significant role in the control of microbial and organic pollution load of wastewater. Also, it is concluded that all parameters were in accordance with the standards of Iran's Department of Environment, so, it can be used for unrestricted irrigation.
Experiments for the characterization of inactivation were performed in a series of batch processes with the total coliform used as a general indicator organism based on the chlorine residuals as a disinfectant. The water samples were taken from the outlet of a settling basin in a conventional surface water treat- ment system that is provided with the raw water drawn from the mid-stream of the Han River, The inactivation of total coliform was experimentally analysed for the dose of disinfectants contact time, filtration and mixing intensity. The curves obtained from a series of batch processes were shaped with a general tailing-off and biphasic mode of inactivation, i.e. a sharp loss of bacterial viability within 15 min followed by an extended phase. In order to observe the effect of carry-over suspended solids on chlorine consumption and disinfection efficiency, the water samples were filtered, prior to inoculation with coliforms, with membranes of both 2.5$\mu$m and 11.0 $\mu$m pore size, and with a sand tilter of 1.0 mm in effective size and of 1.4 in uniformity coefficient. As far as the disinfection efficiency is concerned, there were no significant differences. The parameters estimated by the models of Chick-Wat-son, Hom and Selleck from our experimental data obtained within 120 min are: log(N/N$\_$0/)=-0.16CT with n=1, leg(N/N$\_$0/)=-0.71C$\^$0.87/ with n 1 for the Chick-Watson model, log (N/N$\_$0/)=-1.87C$\^$0.47/ T$\^$0.36/ for the Hom model, log (MHo)=-2.13log (1+CT/0.11) for the Selleck model. It is notable that among the models reviewed with regard to the experimental data obtained, the Selleck model appeared to most closely resemble the total coliform survival curve.
A bacteriological study of sea water and oyster in Tongyeong coastal area was conducted to evaluate sanitary conditions of the bay and compliance of waters with the recommended bacteriological criteria fur the designated area of shellfish cultivation. The Samples were collected at 5 zone, 34 sampling stations(Fig. 1) established once a month from September 1997 to August 1998. During the study period, temperature ranged from 6.9 to 23.6$^{\circ}C$, transparency ranged from 2.6 to 6.2 m, chemical oxygen demand ranged from 1.35 to 1.82 mg/ι, dissolved oxy-gen ranged from 5.0 to 9.9 mg/ι, dissolved nitrogen ranged from 1.60 to 8.17 $\mu\textrm{g}$-at/ι, phosphate ranged from 0.14 to 1.21 $\mu\textrm{g}$-at/ι, Chlorophyll-a ranged from 2.03 to 69.9 mg/㎥, respectively. The coliform group and fecal coliform MPN's of sea water were ranged from <3.0~1,600 and <3.0~540, respectively. The coliform group and fecal coliform MPN's of oysters were ranged from <18~16,000 and <18~2,200, respectively. The viable cell counts in oyster ranged from $1.5\times$10$^2$to 8.2$\times$10$^3$. The coliform stoup, fecal coliform, classification of coliform group with IMViC reactions and pathogenic vibrios were analyzed. 437 strains that were obtained from Tongyeoung coastal area seawater samples represented E. coli group 47.5%, C. freundii group 14.8%, K. aerogenes 10.9%, unknown 26.8%, respectively. During the study period, infectious bacteria such as Vibrio ohoEerae, Salmonella sp. and Shigella sp. were not detected from the samples, but detection ratios of Vibrio parahaemolyticus and Vibrio vulnificus were 12~21% in summer months.
Eighty one products from 36 kinds of vitamin and mineral feed supplement collected during August, 1984 to February, 1985 were examined for microbiological contamination. In addition, 83 strains of coliform isolated from the samples were tested for the resistance to 8 kinds of antimicrobial drugs and distribution of R plasmid. General bacteria were detected in all of samples tested. Bacterial population was varied from less than 10 per gram of the sample to 1,400,000 per gram and 34 (42%) of 81 samples were contaminated with 100 to 1,000 cells per gram. Coliform isolation, which was more frequent in samples with larger number of general bacteria, was possible in 14 (17.3%) out of 81 samples tested and 6 (33.3%) out of 18 companies were coliform positive in their products. Forty one (49.4%) out of 83 coliform isolates were fecal coliform. The frequency of resistant strains was the highest to sulfadimethoxine (Sa) with 92.8% and followed by streptomycin (Sm, 67.5%), tetracycline (Tc, 50.6%), kanamycin (Km, 26.5%), chloramphenicol (Cm, 18.1%) and ampicillin (Am, 15.7%). No strain was resistant to nalidixic acid (Na) and gentamicin (Gm). The resistance frequency of fecal coliform strains were higher compare to non-fecal coliform strains. There were minimum inhibitory concentration (MIC) of $3,200{\mu}g/m{\ell}$ or higher in 7 strains to Am, 3 to Sm and 3 to Km, and 70 strains had MIC of $1,600{\mu}g/m{\ell}$ of higher to Sa while Tc had MICs from $1.6{\mu}g/m{\ell}$ to $400{\mu}g/m{\ell}$. All strains had MICs of $6.3{\mu}g/m{\ell}$ of lower to Na and $3.1{\mu}g/m{\ell}$ of lower to Gm. Seventy nine (95.2%) of 83 strains were resistant to one or more drugs tested. The most frequent resistance patterns were SaSm (14.5%) and followed by SaSmTc(12%), SaSmTcKm(8.4%) SaTc (8.4%) and SaSmKm (7.2%) ; total 19 different patterns were noted. Thirty two (40.5%) of 79 resistant strains were transferred all of a part of their resistance to Escherichia coli ML 1410. The frequency of transferable resistance was high in Am (100%) and Cm (80%) while low in Tc (38.1%), Sa (18.2%), Sm (17.9%) and Km (4.5%).
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