• Korean Journal of Ecology and Environment
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• v.37 no.1 s.106
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• pp.112-121
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• 2004

A study was performed to examine the effects of UV-disinfected reclaimed water on microorganism concentration during rice culture. Four treatments were used and each one was triplicated to evaluate the changes of microorganism concentrations: stream water irrigation (STR), biofilter effluent irrigation (BE), UV-disinfected water irrigation with dose of 6 mW ${\cdot}$ s $cm{-2}$ (UV-6), and UV-disinfected water irrigation with dose of 16 mW ${\cdot}$ s $cm{-2}$ (UV-16). The indicator microorganisms of interest were total coliform (TC), fecal coliform (FC), and E. coli. The biofilter effluent from 16-unit apartment sewage treatment plant was used as reclaimed water and flowthrough type UV-disinfection system was used. Concentrations of indicator microorganisms in the treatment plots ranged from $10^2$ to $10^5$ MPN/100 mL during 24 hours after irrigation in May and June, where initial irrigation water for transplanting reparation was biofilter-effluent without UV-disinfection. It implies that initial irrigation using only non-disinfected reclaimed water for puddling in paddy field can be health-concerned because of more chance of farmer's physical contact with elevated concentration of microorganisms. The concentrations of microorganisms varied widely with rainfall, and treatments using UV-disinfected water irrigation showed significantly lower concentrations than others and their levels were within the range of paddy rice field with normal surface water irrigation. The mean concentrations of STR and BE during growing season were in the range of 4 ${\times}\;10^3$ MPN/100 mL for TC, and 2${\times}\;10^3$ MPN/100 mL for FC and E, Coli, While mean concentrations of UV-S and UV-lS were less than 1${\times}\;10^3$ MPN/100 mL for all the indicator microorganisms. Overall, UV-disinfection was thought to be feasible and practical alternative for agricultural reuse of secondary level effluent in Korea.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.57-65
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• 2013

This study was conducted to evaluate the effect of dietary Weissella koreensis (Wk), a prominent kimchi lactic acid bacteria supplementation on growth performance, nutrients utilization, gut microbiota and meat characteristics in broiler chicken. Both live and killed Wk was compared to know which could be more efficacious as a feed probiotics. Three Wk supplemented groups and no Wk supplemented group were designated according to supplementation levels and cell status. Those were; Control (no Wk), 0.1 % live Wk (LWk 0.1), 0.5% live Wk (LWk 0.5) and 0.5% killed Wk (KWk 0.5). Body weight gain and feed conversion efficiency were improved (P<0.05) by dietary LWk supplementation. KWk did not exert any benefit on growth performance. Crude protein utilizability of KWk supplemented diet was lower (P<0.05) than that of other diets. However, there were no differences among treatments in other nutrients utilization. Serum IgG concentration and relative weight of bursa of Fabricius was highest (P<0.05) in broiler chicken fed KWk 0.5 diet. Cecal anaerobic lactic acid bacteria count of LWk groups were higher (P<0.05) than those of control and KWk 0.5 groups. Dietary Wk supplementation failed to lower the count of cecal and fecal E. coli. There was no effect of dietary Wk on TBARS values and fatty acids profile of broiler leg meat. However, the dietary supplementation of Wk exerted characteristic difference on electronic nose flavor of broiler meat. This study showed that dietary supplementation of LWk was able to improve body weight gain, feed conversion efficiency and cecal lactic acid bacterial count in broiler chicken. Further, the result of this study implemented that a live kimchi lactic acid bacteria, LWk, but not killed Wk, could be used as a probiotic feed supplement for broiler.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.75-81
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• 2013

This experiment was conducted to investigate the effects of bacteriophage SE supplementation on growth performance, nutrient digestibility, blood profiles, visceral organ weight, meat quality and excreta microflora in broilers. A total of 340 1-d-old ROSS 308 broilers (mixed gender) with an initial average body weight (BW) of $41.71{\pm}0.16$ g were randomly allotted to 4 treatments with 5 replicate pens per treatment and 17 broilers per pen for 31 days. Dietary treatments were: 1) CON, control diet, 2) SE05, CON+0.05% bacteriophage, SE 3) SE10, CON+0.10% bacteriophage SE, and 4) SE15, CON+0.15% bacteriophage SE. During d 15 to 31, broilers fed SE15 diet had a higher (P<0.05) body weight gain than broilers fed CON diet. Overall, body weight gain in SE10 and SE15 was greater (P<0.05) than that in CON. Apparent total tract nutrient digestibility and blood characteristics did not differ (P>0.05) among treatments. The water holding capacity was increased (P<0.05) in SE15 compared with CON. Other meat quality in terms of pH value, breast muscle color ($L^*$, $a^*$, $b^*$) and drip loss were unaffected by dietary supplementation with bacteriophage SE. The visceral weight of bursa of Fabricius was increased (P<0.05) in broilers fed the bacteriophage SE incorporated diets compared with those fed the CON diet. No difference (P>0.05) was observed in visceral weight of liver, spleen, breast muscle, abdominal fat, gizzard and excreta concentrations of Lactobacillus, Clostridium perfringens, Escherichia coli, and Salmonella. In conclusion, dietary supplementation with 0.10 and 0.15% bacteriophage SE could improve the growth performance, breast muscle water holding capacity and bursa of Fabricius visceral weight in broilers.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.615-622
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• 2013

The purpose of this study was to evaluate microbial contamination of melons in Korea. A total of 123 samples including melon fruits, leaves, seeds, soils, and irrigation water were collected from farms and markets to detect total aerobic bacteria, coliform, Escherichia coli, and pathogenic bacteria such as Bacillus cereus, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus. Samples were collected from Iksan and Nonsan farms to monitor bacterial levels on pre-market melons. The total aerobic and coliform bacteria on melon cultivation were between 0.43 and 6.65 log CFU $g^{-1}$, and 0.67 and 2.91 log CFU $g^{-1}$, respectively. Bacillus cereus, a fecal coliform, was detected in soils and melon leaves from Iksan farm at 2.95, 0.73 log CFU $g^{-1}$, respectively, and in soils from Nonsan farm at 3.16 log CFU $g^{-1}$. Market melon samples were collected to assay bacterial load on melon being sold to consumers. The contamination levels of total aerobic bacteria in agricultural markets, big-box retailers, and traditional markets were 4.82, 3.94, 3.99 log CFU $g^{-1}$, respectively. The numbers of coliform in melon on the markets ranged from 0.09 to 0.49 log CFU $g^{-1}$. Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus were not detected in any samples. The count of total aerobic bacteria on melon seeds ranged from 0.33 to 3.34 log CFU $g^{-1}$. This study found that irrigation water, soil, manure and various farm work activities including post-harvest processes were latent sources of microbial contamination. These results suggest that hygienic management and monitoring of soil, water, and agricultural material should be performed to reduce microbial contamination in melon production.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.2
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• pp.161-168
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• 2014

This study aimed to investigate dietary concentrate:forage ratios (C:F) and undegraded dietary protein (UDP) on nitrogen balance and urinary excretion of purine derivatives (PD) in lambs. Four Dorper${\times}$thin-tailed Han crossbred castrated lambs with $62.3{\pm}1.9$ kg body weight at 10 months of age were randomly assigned to four dietary treatments in a $2{\times}2$ factorial arrangement of two levels of C:F (40:60 and 60:40) and two levels of UDP (35% and 50% of CP), according to a complete $4{\times}4$ Latin-square design. Each experimental period lasted for 19 d. After a 7-d adaptation period, lambs were moved into individual metabolism crates for 12 d including 7 d of adaption and 5 d of metabolism trial. During the metabolism trial, total urine was collected for 24 h and spot urine samples were also collected at different times. Urinary PD was measured using a colorimetric method and creatinine was measured using an automated analyzer. Intake of dry matter (DM) (p<0.01) and organic matter (OM) (p<0.01) increased as the level of UDP decreased. Fecal N was not affected by dietary treatment (p>0.05) while urinary N increased as the level of UDP decreased (p<0.05), but decreased as dietary C:F increased (p<0.05). Nitrogen retention increased as dietary C:F increased (p<0.05). As dietary C:F increased, urinary excretion of PD increased (p<0.05), but was not affected by dietary UDP (p>0.05) or interaction between dietary treatments (p>0.05). Daily excretion of creatinine was not affected by dietary treatments (p<0.05), with an average value of $0.334{\times}0.005$ mmol/kg $BW^{0.75}$. A linear correlation was found between total PD excretion and PDC index ($R^2$ = 0.93). Concentrations of creatinine and PDC index in spot urine were unaffected by sampling time (p>0.05) and a good correlation was found between the PDC index (average value of three times) of spot urine and daily excretion of PD ($R^2$ = 0.88). These results suggest that for animals fed ad libitum, the PDC index in spot urine is effective to predict daily excretion of PD. In order to improve the accuracy of the spot sampling technique, an appropriate lag phase between the time of feeding and sampling should be determined so that the sampling time can coincide with the peak concentration of PD in the urine.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.2
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• pp.141-149
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• 2017

To examine the cause of acute diarrheal disease in children and adolescents, 521 fecal samples underwent multiple-PCR for a period of two years, between March 2015 and February 20178, in the Jeju region of Korea. Based on the analysis of 179 positive samples, 102 samples were male (56.98%) and 77 were female (43.02%), and highest positive rates were shown in the age group of 3~4 years (51.96%) and 5~6 years (12.29%). When 209 cases (40.12%), including double infection were analyzed, there were 88 cases (16.89%) of norovirus-GII infection, 26 cases (4.99%) of Campylobacter spp. infection, 18 cases (3.45%) of rotavirus infection, 18 cases (3.45%) of Clostridium difficile Toxin B infection, 17 cases (3.26%) of adenovirus infection, 16 cases (3.07%) of Clostridium perfringens infection, 11 cases (2.11%) of astrovirus infection, 5 cases (0.96%) of Salmonella spp. infection, 3 cases (0.58%) of norovirus-GI, Yersinia spp. and Aeromonas spp. infections, and 1 case (0.19%) of verocytotoxin-producing E. coli infection. Based on a seasonal separation of early childhood, norovirus-GI and norovirus-GII mainly prevailed during the winter, when the temperature is low. Typical enteritis with an increased prevalence of rotavirus during the spring. Astrovirus prevailed between the months of April and October, when norovirus-GI, norovirus-GII, and rotavirus did not prevail. With increasing age, acute diarrheal disease was not only induced by a virus, but also by bacteria. Although a test for virus is an effective method when trying to identify the cause during early childhood by multiplex-PCR, it would be desirable to undergo tests for both virus and bacteria concurrently as age increases.

• Korean Journal of Poultry Science
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• v.42 no.1
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• pp.69-75
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• 2015

This work was carried out to evaluate the feces and ileal digestibility of canola meal and wheat bran in ducks. Ninety Pekin ducks (6-week-old, average 3.4 kg) were divided into three treatments (6 replications/treatment, 5 birds/replication) by feedstuffs (basal diet, canola meal, and wheat bran) and were fed on these diets in individual metabolic cages for one week. After one week, the samples for analysis were collected from feces and ileum. On comparison of treatments and collected sites, the feces digestibility of basal diet was the highest among treatments on chemical compositions except crude protein and crude fat and ileal digestibility of canola meal was the lowest (P<0.01). On comparison of treatments, the digestibility of basal diet was higher and that of wheat bran was lower when compared to other treatments (P<0.05). The feces digestibility was lower than the ileal digestibility in crude protein (P<0.05) and crude fat (P<0.01). The digestibility of amino acid was the highest at feces of control group among treatments (P<0.01). No significant difference was detected in terms of digestibility of isoleucine, leucine and phenylalanine among essential amino acids, and alanine, glycine and tyrosine among non-essential amino acids between control and wheat bran, and wheat bran and canola meal. However amino acid digestibility was higher in control group when compared to canola meal group (P<0.05). Other amino acid digestibilities were not significantly differ by treatments. These results may provide the basic data on amino acid digestibility of ducks to evaluate feedstuffs and to formulate optimum diet for commercial Pekin duck.

• Journal of Food Hygiene and Safety
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• v.34 no.6
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• pp.526-533
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• 2019

The purpose of this study was to investigate hazardous microorganisms in mixed baby leafy vegetables and various baby leafy vegetables used as raw materials for fresh-cut produce in spring and summer. To estimate microbial loads, a total of 298 samples including 181 samples of mixed baby leafy vegetables purchased in a Korean market and 117 samples of various baby leafy vegetables from distribution companies were collected. Fecal indicators (coliform and Escherichia coli) as well as food-borne pathogens (E. coli O157:H7, Salmonella spp., Staphylococcus aureus) were enumerated. As a result, the mixed baby leafy vegetable samples showed significantly higher (P<0.05) coliform bacteria numbers in summer (5.59±1.18 log CFU/g) compared to spring (3.60±2.53 log CFU/g). E. coli was detected in 1.3% (1/79) and 42.2% (43/102) of samples collected in spring and summer, respectively. Only one sample collected from a market in spring was contaminated with S. aureus. In the experiment with baby leafy vegetables, the number of coliforms detected in baby leafy vegetables cultivated in soil in spring was 1.15±1.95 log CFU/g, and that in summer was 4.09±2.52 log CFU/g. However, the number of coliforms recovered from baby leafy vegetables cultivated in media was above 5.0 log CFU/g regardless of season. Occurrences of E. coli were 44.4% (12/27) and 19.0% (4/21) for baby leafy vegetables cultivated in soil and media, respectively. However, E. coli O157:H7 and Salmonella spp. were not detected. These results are in relation to microbial loads on mixed baby leafy vegetables associated with raw materials. Therefore, it is necessary to develop and implement hygienic practices at baby leafy vegetable farms to enhance the safety of fresh produce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.5
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• pp.677-683
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• 2010

This study investigated the effect of young Phragmites communis (Pc) leaves on lipid profiles, lipid metabolism and erythrocyte antioxidant defense system in high-fat diet fed mice. Three groups of mice were fed different diets for 8 weeks: normal diet (Normal), high-fat diet (High-fat; 37% calories from fat) and high-fat diet supplemented with 1% Pc (wt/wt, HF-Pc). Body weight, daily food intake and energy intake tended to decrease by Pc supplement in high-fat fed mice. Pc supplementation significantly lowered plasma triglyceride and total cholesterol concentrations compared to the high-fat control group. Pc also lowered hepatic and heart cholesterol contents, whereas it significantly increased fecal excretion of triglyceride and cholesterol compared to the high-fat control group. Pc significantly inhibited fatty acid synthase, 3-hydroxy-3-methylglutaryl CoA reductase and acyl-CoA:cholesterol acyltransferase activities compared to the high-fat control group. Erythrocyte superoxide dismutase and catalase activities were also significantly higher in the high-fat group than in the normal group, however Pc supplementation reversed these changes. The Pc supplementation significantly lowered erythrocyte lipid peroxidation level compared to the high-fat control group. Accordingly, these results suggest that Pc improves lipid metabolism and erythrocyte antioxidant defense system in high-fat diet fed mice.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.790-795
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• 2005

The effects of liquid culture of Coriolus (C) versicolor on weight gain, food intakes, food efficiency ratios, serum and hepatic lipid concentrations were investigated in male rats fed the high cholesterol diets. Eight weeks old Sprague-Dawley rats were given three different types of diet for six weeks, respectively: a control diet ($ 20\% fat +0.5 \% $ cholesterol), two kinds of C versicolor diet (control diet + $ 30\% or 40\%$C. versicozor in water) according to the levels of C. versicolor supplementation. The body weight gains of the rats fed $ 30\% or 40\% $ C. versicolor diets were lower than those in the rats fed the control diet. The food intake, food efficiency ratios, and liver, kidney, epididymal fat pad weights of the rats fed $ 30\% or 40\%$ C. versicoEer diets were similar to those of the rats fed the control diet. The concentrations of hepatic cholesterol and triglyceride in the rats fed $ 30\% or 40\% $ C. versicolor diets were significantly lower than those in the rats fed the control diet. The concentrations in serum total cholesterol, LDL-cholesterol, and atherogenic index ratios were significantly lower in the rats fed $ 30\% or 40\%$ C. versicolor diets compared to those fed the control diet. The HDL-cholesterol/total-cholesterol ratios was significantly higher in the rats fed $ 30\% or 40\% $ C. versicolor diets compared to those fed the control diet. The fecal excretion of total lipid and triglyceride in the rats fed $ 40\% $ C. versicolor diet was significantly higher than that of the rats fed the control diet. There were no significant difference found in the serum trigly-ceride, phospholipid and HDL-cholesterol concentrations among the experimental groups. These results showed that the C. versicolor feeding decreased the hepatic cholesterol, triglyceride, and the serum total cholesterol, LDL-cholesterol and atherogenic index, and increased the serum HDL-cholesterol/ total-cholesterol ratio of the rats.