1.Antibacterial effects of carvacrol against Staphylococcus aureus and Escherichia coli O157:H7.
Journal of Biomedical Research 2014;15(3):117-122
The objective of this study was to investigate the antimicrobial effects of carvacrol (CV) against Staphylococcus aureus (S. aureus) and Escherichia coli O157:H7 (E. coli O157:H7) strains in milk. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of CV against S. aureus and E. coli O157:H7 were determined. In addition, bactericidal kinetics and antimicrobial activity of CV against the aforementioned pathogens in milk over a period of 2 weeks were investigated. CV exhibited antibacterial activity against both foodborne pathogens tested. The MIC and MBC of CV against S. aureus were 15.0 and 20 mg/mL, respectively, whereas those against E. coli O157:H7 were 16.0 and 32 mg/mL, respectively. In time-kill assays, CV at MBC reduced the number of S. aureus and E. coli O157:H7 in milk to undetectable levels within 24 hr. The antibacterial effects of CV persisted for 14 days without any loss of activity. Results of this study suggest that CV has a potential antibacterial activity against foodborne pathogens such as S. aureus and E. coli O157:H7 in milk.
Escherichia coli*
;
Foodborne Diseases
;
Kinetics
;
Microbial Sensitivity Tests
;
Milk
;
Staphylococcus aureus*
2.Development of an analytical method for the determination of dl-methylephedrine hydrochloride in porcine muscle using liquid chromatography-tandem mass spectrometry
Won-Seok CHAE ; Suk KIM ; Hu-Jang LEE
Korean Journal of Veterinary Research 2020;60(4):209-213
This study examined the residue of dl-methylephedrine hydrochloride (MEP) on the muscle of pigs administered orally with MEP 12 g/ton feed for seven consecutive days. Twenty healthy cross swine were administered MEP. Four treated animals were selected arbitrarily to be sacrificed at 1, 2, 3, 4, and 5 days after treatment. MEP residue concentrations in the muscle were determined by liquid chromatography coupled with tandem mass spectrometry. The drug was extracted from muscle samples using 10 mM ammonium formate in acetonitrile followed by clean-up with n-hexane. The analyte was separated on an XBridgeTM hydrophilic interaction liquid chromatography column using 10 mM ammonium formate in deionized distilled water and acetonitrile. The correlation coefficient (R2 ) of the calibration curve was 0.9974, and the limits of detection and quantification were 0.05 and 0.15 μg/ kg, respectively. The recoveries at three spiking levels were 94.5–101.2%, and the relative Standard Deviations was less than 4.06%.In the MEP-treated group, MEP residues on one day post-treatment were below the maximum residue limit in the muscle. The developed method is sensitive and reliable for the detection of MEP in porcine muscle tissues. Furthermore, it exhibits low quantification limits for animal-derived food products destined for human consumption.
3.Development of an analytical method for the determination of dl-methylephedrine hydrochloride in porcine muscle using liquid chromatography-tandem mass spectrometry
Won-Seok CHAE ; Suk KIM ; Hu-Jang LEE
Korean Journal of Veterinary Research 2020;60(4):209-213
This study examined the residue of dl-methylephedrine hydrochloride (MEP) on the muscle of pigs administered orally with MEP 12 g/ton feed for seven consecutive days. Twenty healthy cross swine were administered MEP. Four treated animals were selected arbitrarily to be sacrificed at 1, 2, 3, 4, and 5 days after treatment. MEP residue concentrations in the muscle were determined by liquid chromatography coupled with tandem mass spectrometry. The drug was extracted from muscle samples using 10 mM ammonium formate in acetonitrile followed by clean-up with n-hexane. The analyte was separated on an XBridgeTM hydrophilic interaction liquid chromatography column using 10 mM ammonium formate in deionized distilled water and acetonitrile. The correlation coefficient (R2 ) of the calibration curve was 0.9974, and the limits of detection and quantification were 0.05 and 0.15 μg/ kg, respectively. The recoveries at three spiking levels were 94.5–101.2%, and the relative Standard Deviations was less than 4.06%.In the MEP-treated group, MEP residues on one day post-treatment were below the maximum residue limit in the muscle. The developed method is sensitive and reliable for the detection of MEP in porcine muscle tissues. Furthermore, it exhibits low quantification limits for animal-derived food products destined for human consumption.
4.Conditions for the disinfectant efficacy test under subzero temperatures
Won Seok CHAE ; Wooseog JEONG ; Hu Jang LEE
Korean Journal of Veterinary Research 2019;59(1):43-45
To establish appropriate conditions for a disinfectant efficacy test at subzero temperatures, this study examined mixtures of frozen foot-and-mouth disease virus or avian influenza virus solutions and disinfectant diluents at −5℃ and monitored temperature and freezing status of an anti-freezing diluent (AFD, 15% ethanol + 30% propylene glycol + 55% distilled water) over time at various subzero temperatures. Viral solutions and disinfectant diluents froze before the mixtures reached −5℃, whereas the AFD was not frozen at −30℃. The times taken for the AFD to reach −10, −20, −30, and −40℃ from room temperature were 36, 39, 45, and 48 min, respectively.
Animals
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Ethanol
;
Foot-and-Mouth Disease Virus
;
Freezing
;
Influenza in Birds
;
Propylene Glycol
5.Conditions for the disinfectant efficacy test under subzero temperatures
Won Seok CHAE ; Wooseog JEONG ; Hu Jang LEE
Korean Journal of Veterinary Research 2019;59(1):43-45
To establish appropriate conditions for a disinfectant efficacy test at subzero temperatures, this study examined mixtures of frozen foot-and-mouth disease virus or avian influenza virus solutions and disinfectant diluents at −5℃ and monitored temperature and freezing status of an anti-freezing diluent (AFD, 15% ethanol + 30% propylene glycol + 55% distilled water) over time at various subzero temperatures. Viral solutions and disinfectant diluents froze before the mixtures reached −5℃, whereas the AFD was not frozen at −30℃. The times taken for the AFD to reach −10, −20, −30, and −40℃ from room temperature were 36, 39, 45, and 48 min, respectively.
6.Comparison of Urea Kinetic Modeling, Standardized Creatinine Clearance and Indices of Nutrition in Continuous Ambulatory Peritoneal Dialysis (CAPD) Patients.
Jong Myoung LEE ; Dong HU ; Yu Seong JEONG ; Ik Deuk JANG ; Hyun Ho BAE ; Jee Yoon KIM ; Joong Kyoung KIM ; Meung Soon YOON ; Si Rhae LEE
Korean Journal of Medicine 1997;52(3):389-399
OBJECTIVES: Protein-calorie malnutrition has been shown to be prevalent among patients on chronic dialysis, And assessment of nutritional status of continuous ambulatory peritoneal dialysis(CAPD) patients has assumed greater importance because of the association of protein-calorie malnutrition with increasing morbidity and mortality. So we observed the incidence and clinical effect of protein-calorie malnutrition, and we compared the indices of nutrition with dialysis adequacy utilizing urea kinetic modeling and cretinine clearance in CAPD patients. METHODS: We performed a cross-sectional study in which eight parameters, based on anthropometry, blood chemistry and subjective symptoms, were scored according to the degree of abnormalities in 82CAPD patients. A malnutrition index was derived from these scores. We also performed comparative analysis to identify significant correlations of the indices of urea kinetic modeling and creatinine clearance with the other parameters of nutritional status. RESULTS: The malnutrition index classified 47(57%) patients as normal, 30(37%) intermediately malnourished, and 5(6%) as severely malnourished. Malnutrition index showed a significant correlation with the body mass index(BMI), triceps skinfold thickness(TSF), mid-arm circumference(MAC), mid-arm muscle area (MAMA), duration of CAPD, subjective symptoms, serum albumin, transferrin, cholesterol, and triglyceride. The malnutrition index also showed a significant correlation with residual renal function(RRF), and standardized creatinine clearance(SCCr). The TWR-Kt/V(total Kt/Vurea per week with consideration of residual renal urea clearance) was significantly lower in the severely malnourished group than in the normal group. Serum alkaline phosphatase and BUN levels were higher in the severely malnourished group than in the normal and inter-mediate groups. CONCLUSION: In assessing the nutrition status of CAPD patients, body weight, TSF, MAC, MAMA, subjective symptoms, serum albumin, transferrin, cholesterol, triglyceride, urea nitrogen, and alkaline phosphatase were considered useful parameters. There was a trend of increased BUN and decreased TWR-Kt/V in severely malnourished patients, and the value of SCCr was significantly lower in malnourished patients. However, no meaningful relationships between TW-Kt/V and malnutrition index or between NPCR(normalized protein catabolic rate) and malnutrition index were found m this cross-sectional study. As the number of patients with longer duration of CAPD or negligible RRF has increased in the malnourished patients, regular monitoring of these parameters, especially TWR-Kt/V and SCCr, may be helpful to assess dialysis adequacy to keep good nutritional status of each CAPD patient.
Alkaline Phosphatase
;
Anthropometry
;
Body Weight
;
Chemistry
;
Cholesterol
;
Creatinine*
;
Cross-Sectional Studies
;
Dialysis
;
Humans
;
Incidence
;
Malnutrition
;
Mortality
;
Nitrogen
;
Nutritional Status
;
Peritoneal Dialysis, Continuous Ambulatory*
;
Protein-Energy Malnutrition
;
Serum Albumin
;
Transferrin
;
Triglycerides
;
Urea*
7.Anti-diabetic effects of aqueous extract of Dendropanax morbifera Lev. leaves in streptozotocin-induced diabetic Sprague-Dawley rats
Min-Jae KIM ; Ye-Jin KANG ; Dong-Eon LEE ; Suk KIM ; Se-Hun LIM ; Hu-Jang LEE
Korean Journal of Veterinary Research 2021;61(4):e38-
This study examined the anti-diabetic effects of aqueous extracts of Dendropanax morbifera leaves (DMWEs) in streptozotocin-induced diabetic Sprague-Dawley (SD) rats. Thirty male SD rats (body weight [BW], 250.4 ± 19.7 g) were divided into the following six groups: normal control rats (NC), diabetic control rats (DC), diabetic rats treated with metformin HCl 100 mg/kg BW (DT), diabetic rats treated with DMWEs 50 mg/kg BW (DM-50), diabetic rats treated with DMWEs 100 mg/kg BW (DM-100), and diabetic rats treated with DMWEs 200 mg/kg BW (DM-200). From two weeks of administration of DMWEs, the BW of all groups treated with DMWEs increased significantly compared to DC (p < 0.05). At four weeks after treatment, the blood glucose levels in DT, DM-100, and DM-200 decreased below 200 mg/dL, while the glycated hemoglobin concentrations in all groups administered DMWEs were similar to those of NC and DT. Regarding the blood biochemical parameters, the levels of aspartate transaminase, alanine transaminase, blood urea nitrogen, and creatinine in DM-100 and DM-200 were similar to those in NC and DT. Overall, these results highlight the effectiveness of DM-100 in the treatment of diabetes.
8.Analysis of antibiotic residues in milk from healthy dairy cows treated with bovine mastitis ointment using ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry.
Eun Kee PARK ; Yong Jae RYU ; Chun Nam CHA ; Chang Yeul YOO ; Suk KIM ; Hu Jang LEE
Korean Journal of Veterinary Research 2016;56(4):233-239
This study was conducted to analyze penicillin G (PEG), streptomycin (STR) and neomycin (NEO) residues in milk of healthy lactating cows. Milk samples were collected from all four quarters of 12 dairy cows 2–7 days after intramammary infusions of an ointment containing PEG, STR and NEO once (n = 4; group I) or twice (n = 4, group II) daily. Ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry was used to determine the antibiotic residues in the samples. The correlation coefficient (r 2) of the calibration curves for all antibiotics was > 0.999 and the limits of detection and quantification were 0.002–0.005 µg/mL and 0.007–0.02 µg/mL, respectively. Recovery rates were ranged from 75.5 to 92.3%. In group I, PEG, STR and NEO residues were detected in milk at 2, 3 and 2 days post-treatment, respectively, which were below the maximum residue limit (MRL). In group II, PEG, STR and NEO residues were detected in milk at 2, 3 and 3 days post-treatment, respectively, which were bellow the MRL. These results suggest that a 3-day for milk withdrawal period after the ointment treatment might be sufficient for reduction of the antibiotic residues below the MRL.
9.Influence of various photoperiods on stress hormone production, immune function, and hematological parameters in ICR mice.
Seung Hyu PARK ; Il Gyue KIM ; Hyung Chan KIM ; Mi Jeong GANG ; Song Ee SON ; Hu Jang LEE
Korean Journal of Veterinary Research 2015;55(2):111-116
In the present study, the effects of different photoperiods on stress, immunity, and hematological parameters in ICR mice were evaluated. Fifty male ICR mice 7 weeks old (body weight, 27.3 +/- 2.5 g) were divided into five groups: DP-0 (0/24-h light/dark cycle), DP-6 (6/18-h light/dark cycle), DP-12 (12/12-h light/dark cycle), DP-18 (18/ 6-h light/dark cycle), and DP-24 (24/0-h light/dark cycle). During the experimental period, no significant differences in body weight or feed intake were observed between the groups. Hematological analysis revealed that white blood cell, red blood cell, and hemoglobin values for the DP-0 group were significantly different compared to those of the other groups. After 28 days, no significant difference in serum cortisol concentration was observed among the groups, but serum cortisol levels increased in a light exposure-dependent manner. Total serum immunoglobulin G (IgG) concentrations of the DP-0 and PD-6 groups were significantly increased compared to those of the other groups (P < 0.05), and serum total IgG levels decreased in a light exposure-dependent manner. Results of the present study indicated that various photoperiods affect hematological parameters and total serum IgG levels in ICR mice while having no significant effects on body weight, feed intake, or cortisol levels.
Animals
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Body Weight
;
Erythrocytes
;
Humans
;
Hydrocortisone
;
Immunoglobulin G
;
Leukocytes
;
Male
;
Mice
;
Mice, Inbred ICR*
;
Photoperiod*
10.Evaluation of antibacterial and therapeutic effects of egg-white lysozyme against Salmonella Typhimurium in ICR mice infected with Salmonella Typhimurium.
Hee Gyu KIM ; Jae Seung HWANG ; Woo Young JAE ; Song Ee SON ; Hu Jang LEE
Korean Journal of Veterinary Research 2016;56(2):103-108
Salmonellosis is a major bacterial zoonosis that causes self-limited enteritis in animals and foodborne disease and typhoid fever in humans. Recently, multi-drug-resistant strains of Salmonella spp. have increased and caused more serious problems in public health. The present study investigated the antibacterial effects of egg-white lysozyme (EWL) against Salmonella (S.) Typhimurium and the therapeutic effects of EWL for murine salmonellosis. Evaluation of the antibacterial effects of EWL against S. Typhimurium revealed a minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of EWL of 6.25 and 300 µg/mL, respectively. In the bacterial growth inhibition test, EWL at 300 (p < 0.05) and 600 µg/mL (p < 0.01) significantly inhibited the growth of S. Typhimurium at 4 h postincubation. EWL administration at MIC (LYS-1), MBC (LYS-2) and 2× MBC (LYS-3) for 14 days resulted in mortality of mice infected with S. Typhimurium of 70, 40 and 10%, respectively, while that of control mice (CON) was 90%. Counts of S. Typhimurium in murine spleens were significantly lower in LYS-2 and LYS-3 than CON (p < 0.05). The results of this study indicate that EWL has the potential for treatment of ICR mice infected with S. Typhimurium.
Animals
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Enteritis
;
Foodborne Diseases
;
Humans
;
Mice
;
Mice, Inbred ICR*
;
Microbial Sensitivity Tests
;
Mortality
;
Muramidase*
;
Public Health
;
Salmonella Infections
;
Salmonella typhimurium*
;
Salmonella*
;
Spleen
;
Therapeutic Uses*
;
Typhoid Fever