• Journal of Marine Life Science
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• v.2 no.2
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• pp.56-61
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• 2017

This study examined the environmental characteristics of shore pollution sources in the southern part of the Sinan, Jangsando area in the West Coast of Korea. A shoreline survey of the watershed was conducted to identify the pollution sources and measure the water discharge rate and microbial hygiene of water and finally estimate the possible impact area of pollution. Forty five of pollution sources in total were identified and they were grouped into sewage (33), agriculture waste water (1) and waste water from inland fish farm (11). Nine among them were discharged into the seawater and discharge volume was 72,857~281,250 l/min. Fecal coliforms of St. 72 (sewage) and St. 74 (shrimp farm) were 490 MPN/100 ml and 49 MPN/100 ml and the impact zones of the pollution were 4,389 m and 1,900 m respectively.

• Journal of Korean Society on Water Environment
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• v.26 no.2
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• pp.261-267
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• 2010

In order to evaluate the distribution level of Cryptosporidium and Giardia in drinking water resources, distribution of Cryptosporidium and Giardia was studied in intake water of main water treatment facility with treatment capacity over 50,000 ton/day in Korea. 10 L samples from each study sites were collected quarterly for 2 years between Oct. '04 and Dec. '07. Cryptosporidium and Giardia were filtered and concentrated by capsule filter and centrifugation, and analyzed by immunomagnetic separation process and fluorescent assay. Cryptosporidium oocysts and Giardia cysts were detected in 7.0% and 9.3%, respectively, of a total 776 samples from 97 study sites. And mean detection number of Cryptosporidium oocysts and Giardia cysts in total 776 samples was 0.11/10 L, 0.16/10 L, detection range of Cryptosporidium oocysts and Giardia cysts was 0~7/10 L, 0~4/10 L, respectively. In seasonal distribution, Cryptosporidium was more frequent in spring as 9.2% than other season, Giardia was more frequent in winter as 14.6% than other season, but there was not shown significant seasonal characteristics. In correlation analysis with total 776 data, Cryptosporidium had significant correlation to total coliforms at the 0.05 level, but correlation value was too low as 0.07 (r=0.07). In case of Giardia, what had significant correlation at the 0.05 level was total coliforms and fecal coliforms, but correlation value was too low as 0.26, 0.27 respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.992-1001
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• 2020

Objective: This study was conducted to investigate the effects of hot-melt extruded ZnO nano-particles (HME-ZnO) as an alternative for P-ZnO on growth performance, nutrient digestibility, Zn bioavailability, intestinal microbiota, and intestinal morphology of weanling pigs. Methods: A total of 450 piglets (Landrace×Yorkshire×Duroc) were randomly allotted to five treatments based on initial body weight and sex. The experimental diets were fed in a meal form as phase 1 from d 0 to 14 and phase 2 from d 15 to 28. Treatments were the control diet without ZnO supplementation, the diet containing 2,500 ppm Zn as ZnO, and three diets containing 500, 1,000, or 2,500 ppm Zn as HME-ZnO. Results: The overall result showed a higher (p<0.01) average daily gain in weanling pigs fed ZnO-supplemented diets in comparison to the control diet. There was a decrease (p<0.01) in fecal score in the ZnO-supplemented diets. Dietary supplementation of ZnO improved (p<0.05) crude protein digestibility. The weanling pigs fed the P-ZnO diet had a lower (p<0.01) Zn digestibility in the feces than HME-ZnO supplemented treatments. Weanling pigs fed diets supplemented with ZnO had greater (p<0.05) Lactobacillus spp. populations and lower Clostridium spp. (p<0.05) and Coliforms (p<0.01) populations in the ileum. Weanling pigs fed diets supplemented with increasing concentrations of HME-ZnO linearly decreased Clostridium spp. (p<0.05) and Coliforms (p<0.01) in the ileum. Lower (p<0.05) Clostridium spp. and Coliforms counts in the colon were observed in pigs fed with ZnO-supplemented diets. Weanling pigs fed diets supplemented with ZnO showed a greater (p<0.01) villus height in the duodenum. Conclusion: Dietary supplementation of HME-ZnO and P-ZnO showed a potential to improve the digestibility of protein, intestinal Coliform and Clostridium, villus height in duodenum and ileum. Moreover, HME-ZnO showed a higher Zn digestibility compared with P-ZnO.

• Journal of Microbiology
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• v.45 no.5
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• pp.379-387
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• 2007

A hundred and seventeen antibiotic-resistant Escherichia coli strains were isolated from public tap and spring waters which were polluted by fecal coliforms. There were no significant differences between two water sources as to the coliform pollution level (p> 0.05). All E. coli isolates were detected to be resistant to one or more antibiotics tested. Nearly 42% of the isolates showed multiresistant phenotype. Three (2.5%) of these isolates contained class 1 integron. Sequencing analysis of variable regions of the class 1 integrons showed two gene cassette arrays, dfr1-aadA1 and dhfrA17-aadA5. Resistance to ampicillin, tetracycline or trimethoprim-sulfamethoxazole was transferable according to the results of conjugation experiments. The rate of tetracycline resistance was 15%. tet(A)-mediated tetracycline resistance was widespread among tetracycline-resistant E. coli isolates. Genotyping by BOX-polymerase chain reaction (BOX-PCR) showed that some of the strains were epidemiologically related. This is the first report on the prevalence and characterization of class 1 integron-containing E. coli isolates of environmental origin in Turkey.

• Korean Journal of Community Nutrition
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• v.5 no.2
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• pp.333-342
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• 2000

The purpose of this study was to evaluate microbiological quality for each stage of the kimbap manufacturing process in summer and winter. Under the various controlled conditions through the simulation, the time-temperature data were collected and the microbiological quality(including total plate count, coliforms, and fecal coliform count) were evaluated. To determine the expected shelf life of Kimbap, a microbiolgical analysis according to the length of the storage time was performed. The microbiological analysis on both sanitary and unsanitary utensils was compared. The microbiological quality of the raw materials of Kimbap in summer was not at an acceptable level, but that of the heat-treated raw materials of Kimbap met the requirement according to the standards set by the Natick Research Center. The number of the microorganisms of the unsanitary utensils and the Kimbap made from unsanitary utensils was more than the acceptable criteria. Sanitary management is necessary to prohibit cross-contamination and to manufacture Kimbap safely. Results from storage times and storage temperature conditions(chilled and room-temperature storage) showed that the expected shelf-life of the Kimbap with the room-temperature storage was as less than 3 hours in summer, while it was as 7-10 hours in winter.

• Journal of Environmental Health Sciences
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• v.43 no.2
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• pp.143-156
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• 2017

The purpose of this study was to investigate water quality through a field survey at six floor fountain sites. The floor fountain facilities were designed and operated in such a way that tap water was stored in a water tank and recycled repeatedly. The water tank was cleaned once or twice per week in the summer. The number of facility users was low during the day due to sweltering heat, but up to 40 people, mainly children, were using them around 8 pm. Since the operation time was as short as 30 minutes, it is considered necessary to extend it for at least one hour for the number of users. As a result of the water quality test of the reservoir tank prior to operation after cleaning, it was measured to be within drinking water quality standards at the six facilities. As a result of the water quality test after use, ammonia nitrogen was measured to be 1.45 mg/L at Site IV. This exceeded the drinking water quality standard of 0.5 mg/L. In the case of turbidity, two cases exceed at 7.38 and 4.52 NTU when applying 4 NTU as the water quality standard for waterscape facilities. Twenty-eight cases exceed the standard of drinking water quality. The result of microbiological tests, at five sites excepting Site I, where disinfectant was injected, was that the maximum total colony count was 180,000 CFU/mL, total coliforms was 2,100,000 CFU/100 mL, fecal coliforms was 4,600 CFU/100 mL, Escherichia coli was 170 MPN/100 mL and Enterococcus was 100 CFU/100 mL. This exceeded the water quality standards of drinking water. Children are very likely to inhale because the water spews from below and falls from above, so it is necessary to apply water quality standards for ammonia nitrogen, turbidity and microbes. Current floor fountain facilities are highly susceptible to disease caused by microbial contamination because of water cycling and reuse, so it is necessary to change the water every day, clean the water tank, and perform chlorination. Therefore, it is necessary to inject calcium hypochlorite according to the free chlorine water quality standard of swimming pools with a different water tank capacity. In addition, facilities should be improved to prevent the reuse of water by installing the water tank at a separate location.

• Journal of Animal Science and Technology
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• v.64 no.1
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• pp.70-83
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• 2022

A set of studies was performed to determine the influence of dietary ZnO concentration and source during two phases (days 0 to 14 and days 15 to 28). Experiment 1: 168 weaned piglets were allocated to four treatment groups in six replicates. The treatments included a basal diet without ZnO supplementation (control), 2,500 mg ZnO/kg (In2500), 500 mg nano-ZnO/kg (N500), and 150 mg nano-ZnO/kg (N150). Experiment 2: 168 weaned piglets were divided into three treatment groups with eight replicates. The treatments included control, In2500, N300, and 150 mg nano-ZnO/kg (N150). An in vitro trial showed that the growth of Listeria monocytogenes, Escherichia coli, and Salmonella typhimurium was inhibited when exposed to 300 and 500 ppm of ZnO after 24 h of incubation. In experiment 1, the average daily gain (ADG) by the pigs was improved in the N500 and IN2500 treatment groups. Colonization of coliforms and Clostridium spp. significantly decreased in the pigs fed the N500 and IN2500 diets in phase 1. The total plasma antioxidant capacity was greater in the IN2500 and N500 treatment groups than in the control. Superoxide dismutase (SOD) activity was greater in pigs fed the IN2500 (phase 1) or the IN2500 and N500 (phase 2) diets than in the control and N150 treatment group. In experiment 2, pigs in the N300 treatment group showed a higher ADG and lower fecal score colonization of coliforms and Clostridium spp. compared with those in the N150 treatment group. In conclusion, nano-ZnO at a dose of 300 ppm showed the same growth as the pharmacological dose of Zn. This provides an option to the pharmacological dose.

• Journal of Environmental Health Sciences
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• v.15 no.2
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• pp.11-23
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• 1989

This study was performed to investigate present water quality and pollution characteristics of them in the basin area of the Mankyung river near Chonju urban stream. In order to obtain the pollution characteristics of this investigation, the physio-chemical water analysis as temperature, pH, DO, BOD, Cd, Cu, Pb and Zn, and coliform group and their correlation analysis were determined from March to August 1988. The main results were summarized as follows 1. Each chemical constituent detected in three streams has the following variation range as pH(6.7-7.3), DO(1.3-8.9 mg/l), BOD(1.6-162.5mg/l) and water temperature was dominated by atmospheric temperature. 2. In three streams, concentration range of heavy metal was Cd N.D.-2.8 $\mu$g/l, Cu 1.1-10.2 $\mu$g/l, Pb 2.1-13.2 $\mu$g/l and Zn 25.6-62.2 $\mu$g/l, and was shown the order of Zn, Pb, Cu and Cd. 3. In the investigation on the bacteriological pollution-in the three streams. 1) The average number of general bacteria contaminated in the Chonju urban stream was $1.7 \times 10^{5}$ numbers/ml, which was higher than $2.6 \times 10^{2}$ numbers/ml, in the Gosan stream and 1.6 $\times$ 10 numbers/ml in the Mankyung river. 2) The average number of total coliform, fecal coliform and fecal streptococcus contaminated in the Chonju urban stream which was the highest polluted site than those of the other sampling sites were respectively $2.1 \times 10^{5}$, $2.1 \times 10^{5}$ and $9.6 \times 10^{4}$ MPN/100ml. 4. Correlation coefficient between GB and TC in the Chonju stream, Gosan stream and Mankyung river was respectively 0.99, 0.96 and 0.99, Correlation coefficient between TC and FC in Chonju stream, Gosan stream and Mankyung river was respectively 0.99, 0.97 and 0.99 and correlation coefficient between FC and TC was respectively 0.99, 0.91 and 0.99. This results mean positively dose relationship between them. 5. The occupied percentage of FC of TC in the Chonju stream, Gosan stream and Mankyung river was respectively 88.1%, 68.4% and 77.9% and the percentage of Tc of TS was respectively 43.5%, 31.6% and 41.4%. These .results was considered indicative of pollution derived from domestic wastes which had been contaminated by the feces of inhabitants and domestic animals.

• Journal of the Korean Dietetic Association
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• v.4 no.2
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• pp.235-244
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• 1998

Hand washing is an important component of hygiene program for food handlers. Hands can be a source of direct or indirect contamination of foods with pathogenic microorganisms. In this study, the effectiveness of hand washing methods and the use of 70% alcohol solution against transient skin bacteria was tested in an university foodservice facility. 70% alcohol solution is sprayed for 5 seconds automatically when hands are placed in the dispenser. Samples were taken using swab technique in meat cutting area, vegetable trimming area, and vegetable cutting area: before and after washing hands according to planned methods, and after being sprayed with 70% alcohol solution after washing hands. The bacteriological analysis of total plate counts, coliform, fecal coliform of food handlers' hands was done. Statistical data analysis was completed with Mann-Whitney U test and Kruskal-Wallis model using the SPSS program. The levels of initial contamination of workers' hand were significantly different by the work areas($x^2$=9.156, p<0.01). Workers in the vegetable trimming area had more heavily soiled hands than in the other work areas. Mean of TPC counts and coliform was 8.97×$10^5$ CFU/12.4$cm^2$, 2.93×$10^2$ MPN/12.4$cm^2$ respectively, but fecal coliform was not detected. Transient bacteria were removed from hands after washing and using 70% alcohol solution but were not removed completely. Mean reduction percentage in TPC varied among work areas and ranged from 93.19% to 94.99%, and in coliforms from 97.31% to 100%. A significant difference in TPC was found between before and after hand disinfection (Z=-2.714, p<.01) and between standardized hand washing procedures and un-standardized hand washing procedures(z=-2.301, p<.01). Subjects using the hand sanitizer showed a great elimination of TPC(99.45% reduction), but this effect was valid only after following proper washing procedures. Based on the results, the most effective hand washing method was recommended as the combination of the standardized hand washing procedure with warm-water and use of the 70% alcohol solution. The results can be used to develop hand hygiene programs and training strategies for enhancing hand hygiene practices for food handlers in foodservice operations.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.154-159
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• 2011

Inadequate food handling and poor hand hygiene playa major role in the occurrence of foodborne diseases. The objective of this study was to find out if the level of microbial contamination on the hands of food preparers varies by time during their working period. This study focused on the contamination of aerobic plate count, total and fecal coliforms, Escherichia coli, Staphylococcus aureus, and Salmonella spp. Sampling from left hand and right hand of twenty food preparers was done with glove-juice method at every two hours during their work. Microbiological testing was conducted according to the Food Code of Korea. The microbiological load on the hands was changed over time. Samples taken from their hands before work and at 8 hours showed higher levels of bacteria than those taken at 2, 4, and 6 hours during work and/or after work (p < 0.05). The contamination levels of microorganisms were consistently higher in right hand than in left hand. Poor hand hygiene practices were indicated by the positive results for total and fecal coli forms, E. coli, S. aureus, and Salmonella spp. on the hands of some food preparers. This study indicates food preparers' hands can be a vehicle of pathogen during their work. The results of this study emphasize the importance of hand hygiene education and training targeting the food preparers.