• Journal of Food Hygiene and Safety
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• v.9 no.3
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• pp.123-131
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• 1994

An enzyme-linked immunosorbent assay(ELISA) was developed for the detection of residual gentamicin(GM) in edible animal products. The immunogen(GM-KLH conjugate) and coating antigen(GM-BSA conjugate) were prepared by coupling GM sulfate to keyhole limpet hemocyanin(KLH) and bovine serum albumin(BSA) in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, respectively. Polyclonal antibody to GM was produced in rabbits(New Zealand White, female) by using the immunogen and the antibody titer was measured by indirect ELISA. A competitive ELISA was developed using GM-bovine serum albumin conjugate as a coating antigen, GM(as standards or sample), polyclonal antibody to GM, secondary antibody conjugated with horseradish peroxidase as an enzyme, and H2O2 and o-phenylenediamine dihydrochloride as a substrate and a chromophore, respectively. The detection limit of GM was 10 ng/ml and the standard curve of GM(n=26) was linear up to 10 $\mu\textrm{g}$/ml in this competitive ELISA system. There were no cross-reactivities of the partially purified antibody between GM and the various antibiotice such as amikacin, benzyl-penicillin, chloramphenicol, erythromycin, furazlidone, kanamycin, neomycin, oleandomycin, streptomycin, sulfathiazole and thiamphenicol(CR50<0.05%)

• International Journal of Oral Biology
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• v.31 no.1
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• pp.7-10
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• 2006

Mitis-salivarius sucrose bacitracin(MSB) medium is widely used in the selective isolation of mutans streptococci(MS), a designation for a group of oral cariogenic species. Recently, we have isolated three bacterial strains grown on MSB agar from human dental plaques. The three strains exhibited biochemical characteristics similar to those of the biotype IV of MS, with the exception that they manifested a positive reaction for arginine deaminase. The objective of this study was to identify and characterize these three clinical isolates. The bacteria were identified with biochemical tests as well as by 16S rDNA cloning and sequencing. In order to compare the antibiotics susceptibility of the clinical isolates with that of type strain, the minimum inhibitory concentrations of 9 antibiotics were determined using broth dilution assays. The results identified all of our three clinical isolates as Enterococcus faecalis. All E. faecalis strains were found to be susceptible to penicillin G, amoxicillin, augmentin, and vancomycin, but were resistant to ciprofloxacin, cefuroxim axetil, and clindamycin. Our findings indicate that E. faecalis is capable of growing on MSB agar, and suggest that the MSB medium be improved so that only MS should be recoverable on the medium, as originally devised for their selection.

• Food Science of Animal Resources
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• v.38 no.2
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• pp.391-402
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• 2018

The aim of the present work was to provide information about Enterococcus strains isolated from pre-packaged chicken samples in Ankara (Turkey), focusing on their prevalence, phenotypic and genotypic characteristics, and antibiotic resistance. We report the first study on the occurrence of antibiotic resistant enterococci in pre-packaged chicken samples in Ankara. A total of 97 suspicious enterococcal isolates were identified from 122 chicken samples. All isolates were identified to species level by phenotypic and molecular methods. In the 16S rDNA sequence analysis, Enterococcus faecium (61.85%) and Enterococcus faecalis (38.15%) were found to be the most frequently detected Enterococcus spp. Of the 97 isolates tested for hemolytic activity, 12.37% enterococcal strains were ${\beta}$-hemolytic. ${\beta}$-Hemolysin was most prevalent among E. faecium (58.33%) compared to E. faecalis (41.66%). Disk diffusion method was used for determining of antibiotic resistance. The analysis of the antimicrobial resistance of the 97 Enterococcus isolates revealed that the resistance to kanamycin (98.96%), rifampicin (80.41%) and ampicillin (60.82%) was most frequent. Furthermore, resistance to erythromycin (38.14%) and ciprofloxacin (34.02%) was also observed. The frequencies of resistance to tetracycline (9.27%), penicillin G (8.24%), and chloramphenicol (3.09%), gentamicin (2.06%) and streptomycin (1.03%) were low. None of the isolates was resistant to vancomycin. Multi-drug resistance was found in 97.93% of Enterococcus strains. E. faecium strains showed a more resistant phenotype than E. faecalis strains according to the antibiotic resistance levels. The results of this study indicated that chicken meat is a potential reservoir for the transmission of antibiotic resistance from animals to humans.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.470-476
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• 2007

To evaluate the vancomycin resistance of Enterococcus spp. (VRE) from Saengsik and Sunsik, Enterococcus were isolated and identified from 25 Saengsik and 35 Sunsik samples, and resistance of Enterococcus to other antibiotics was also assessed. Thirty nine Enterococcus, 16 strains from Saengsik, and 23 strains from Sunsik, were ultimately isolated. The most frequently collected Enterococcus isolates in Saengsik were E. casseliflavus and E. hirae, and were E. casseliflavus and E. faecium in Sunsik. However, E. faecalis was not detected in those foods. Minimum inhibitory concentrations of vancomycin against the isolates were below $4\;{\mu}g/mL$ and no strains evidenced profound levels of resistance. The isolates were found to be susceptible to vancomycin with the exception of eight E. casseliflavus and three E. gallinarum. All Enterococcus isolates proved resistant to streptomycin and chloramphenicol. 23% of the isolates were resistant to penicillin; however, all of the isolates were sensitive to tetracycline. Six and 48%, respectively, of the strains from the Saengsik and Sunsik proved resistant to erythromycin. All of E. mundtii and E. hirae isolates from Saengsik, and 20% of E. gallinarum and E. casseliflavus isolates from Sunsik were found to be ampicillin-resistant. All of E. gallinarum, E. casseliflavus, and E. faecium were rifampin-resistant. The antibiotic resistances of Enterococcus were relatively low, and this low vancomycin resistance was similar to that evidenced by Enterococcus isolates obtained from the other foods. However, there may be a need for some review of the accepted antibiotics criteria for Enterococcus and VRE in ready-to-eat foods.

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.202-207
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• 1994

A mutant strain PRM1 defective in light-activated heterotrophic growth was isolated from Synechocystis sp. PCC 6803. PRM1 could be grown at growth rate equivalent to Synechocystis 6803 under mixotrophic growth conditions. However, PRM1 could not be grown under light-activated heterotrophic conditions, in which a daily pulse of light for 5 min was given. These results suggest that PRM1 is not defective in heterotrophic metabolism, but in the transduction pathway of light signal essential to the growth. Plasmid patterns, absorption spectra of whole cells, and the exterior and interior structures of PRM1 were similar to those of Synechocystis 6803, except that PRM1 could not produce amorphous slime holding cells together.

• Journal of Embryo Transfer
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• v.17 no.2
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• pp.123-128
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• 2002

The present study aimed at determining the effective dose of Folltropin, a follicle timulating hormone (FSH), on superovulation in indigenous cows of Bangladesh. Fifteen regularly cycling 5～7 years old dry cows, weighing 200～250 kg with 2.5～3.0 body condition scores (BCS) were divided into three groups (n＝5). Individual groups were superovulated with 100, 200 or 300 mg of Folltropin per animal. The superovulation treatment was initiated at Day 10 or Day 11 of the estrous cycle (Day 0＝day of estrus). Alfaprostol (6 mg) was injected to each cow 72 h after the initiation of superovulation treatment to induce eestrus. After confirming standing estrus, the cows were inseminated 2～3 times, 12 h apart, depending on the duration of estrus. At Day 6 or Day 7, individual horns of the uterus were flushed with 150～200 $m\ell$ of phosphate buffered saline supplemented with BSA (0.2％), penicillin (100 IU／$m\ell$) and streptomycin (100 $\mu\textrm{g}$／$m\ell$) using a two-way foley catheter. The embryos were concentrated, removing the excess medium through an embryo filter, and identified under a stereomicroscope. The identified embryos were collected, washed four times, evaluated and graded as excellent, good, fair or poor. The excellent, good and fair embryos were considered as transferable quality embryos. The mean (range). numbers of embryos collected vs. transferable quality embryos far 100, 200 and 300 mg of Folltropin were 4.5 (1～10) vs. 3.5 (1～8); 2.5 (1～4) vs. 1 (0～2) and 0.0 (0～0) vs. 0.0 (0～0), respectively, Folltropin at a dose of 100 or 200 mg produced suitable ovarian stimulation for superovulation in indigenous zebu cows of Bangladesh. A dose of 300 mg or more Folltropin consistently caused preovulatory corpora lutea formation in the ovaries and resulted in zero embryo recovery.

• Korean Journal of Clinical Laboratory Science
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• v.42 no.2
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• pp.86-91
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• 2010

We evaluated the performance of a novel screening test, PBP2a MRSA rapid kit (Dinona Inc., Iksan, Korea), for methicillin-resistant Staphylococcus aureus (MRSA) based on a immunochromatographic assay. The test is able to detect penicillin-binding protein 2a (PBP2a) using the nasal specimens from health care workers. The nasal specimens were obtained from 69 healthcare workers and were incubated in enrichment broth followed eight hours incubatin in BHI with cefoxitin $4{\mu}g/mL$. These broth were tested by PBP2a Rapid Kit. The enrichment broths were also directly tested for tube coagulase using the conventional identification method. 19 of 22 MRSA showed positive results by PBP2a rapid test and direct coagulase test (the sensitivity for detection of MRSA, 86.36%). While, 8 of 47 non-MRSA showed false positive results for the two tests. All of the 8 non-MRSA which showed false positive were co-colonizing isolates with MRCNS and MSSA. In addition, 46 of 49 methicillin-resistant staphylococci (MRS) showed positive results for PBP2a MRSA rapid kit (the sensitivity for detection of MRS, 93.8%), and all of 20 non-MRS showed negative results (specificity, 100%). The combination of PBP2a MRSA rapid kit and direct coagulase test showed the good sensitivity for detection of MRSA from anterior nares but frequently showed false positive results from the co-colonizing carrier with MRCNS and MSSA.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1336-1342
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• 2005

The present research work was conducted to evaluate the beneficial effects as well as the safety aspects of lactobacilli as probiotic. Lactobacilli were isolated from poultry faecal samples, feed samples and from some known preparations procured from poultry feed manufacturers. L. acidophilus and L. sporogenes were tested for the antibacterial activity against four poultry pathogens viz. Escherichia coli, Salmonella spp., Proteus spp. and Pseudomonas aeruginosa. Cell free supernatant (CFS) of L. acidophilus exhibited significantly higher antibacterial activity against Salmonella spp. at original pH (4.50${\pm}$0.02). At the adjusted pH (6.50${\pm}$0.02) significantly higher antibacterial activity was recorded against indicator organism except for P. aeruginosa. Likewise, L. sporogenes exhibited similar antibacterial activity at original as well as adjusted pH except for E. coli. Antibacterial activity against E. coli was significantly higher at adjusted pH than at original pH of CFS. The competitive exclusion of E. coli by lactobacilli over the intestinal epithelial cells (IEC) was checked. L. acidophilus strain I, which was of poultry origin, exhibited maximum attachment over IEC as compared to other three strains of non-poultry origin viz. L. acidophilus strain II, L. sporogenes strain I and II. Overall, L. acidophilus exhibited higher competitive exclusion as compared to L. sporogenes. All the lactobacilli of poultry origin were most sensitive to penicillin G, amoxycillin, ampicillin and chloramphenicol, least sensitive to sulphamethizole, ciprofloxacin, neomycin, norfloxacin and pefloxacin and resistant to metronidazole and nalidixic acid. The isolates from probiotic preparations were most sensitive to ampicillin, amoxycillin and tetracycline, least sensitive to sulphamethizole, norfloxacin, neomycin and ceftriazone and resistant to nalidixic acid and metronidazole. Eight of the multiple drug resistant lactobacilli isolates were studied for the presence of plasmids. Plasmids could be extracted from six isolates of lactobacilli. These plasmids could be responsible for bacteriocin production or for antibiotic resistance of the strains. The lactobacilli need further studies regarding their safety for use in the probiotic preparations.

• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.19-28
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• 2000

There are several main antibacterial susceptibility tests, such as agar dilution method, broth dilution method and disk diffusion technique. Especially, for minimal inhibitory concentration (MIC) test, agar dilution method has been widely used. But that method is so complicated and bothering that it's difficult to treat a large amount of strains. On the other hand, modified broth dilution method(add 1% glucose and 0.018% phenol red as a pH indicator to broth) is fast and easy to perform. Most of all, it can visualize the result by color. The MICs of 22 antibiotics Including penicillins, aminoglycosides, cephalothin, chloramphenicol, lincomycin, ceftiofur, vancomycin and quinolones, erythromycin, colistin. sul-fadimethoxine, trimethoprim for arcanobacterium pyogenes 14 strains, actinobacillus pleuropneu-moniae 41 strains and pasteurella multocida 37 strains, which were collected from porcine during 1996 ∼ 1999, were determined by modified broth dilution method. Actinobacillus pleuropneumoniae was highly susceptible to all kinds of quinolones such as ciprofloxacin, enrofloxacin and norfloxacin and to all aminoglycosides, like gentamicin, apramycin, kanamycin and ampicillin, cephalothin and ceftiofur. But It was quite resistant to solfadimethoxin, colistin and vancomycin. Pasteurella multocida was found to have high susceptibility to ampicillin, cephalothin, chlorampenicol and gentamicin but had mid-degree susceptibility to other aminoglycosides. In addition, it was susceptible to norfloxacin and nalidixic acid, but not to newer fluoroquinolone like ciprofloxacin and enrofloxacin and it was resistant to colistin and kanamycin. Arcanobacterium pyogenes was highly susceptible to most of quinolones such as cipoofloxacin, enrofloxacin and norfloxacin and gentamicin and penicillin G. But it also obtained high resistance against the early quinolone, nalidixic acid and aminoglycosides such as amikacin, apramycin and kanamycin and erythromycin, chlorampenicol, tetracyclin and vancomycin.

• Korean Journal of Microbiology
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• v.23 no.1
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• pp.1-8
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• 1985

Three strains (JC1, JC2, and HY1) of aerobic carbon monoxide (CO)-utilizing Acinetobacter were isolated from soil through CO-enrichment culture technique. All of them were Gram-negative, nonmotile, and rod-shated but they were changed to spherical form at the end of logarithmic phase. They were resistant to penicillin and able to frow at $42^{\circ}C$. The guanine plus cytosine contents of the DNAs ranged from 43 to 44.5 mol%. Oxidase was not present in all cells. The colonies were smooth and whitish yellow. Heterotrophic growth occurred on several sugars, organic acids, amino acids, and alcohols. The doubling times under and atmosphere of 30% CO and 70% air at $30^{\circ}C$ were 19h, 25h, and 35h, respectively, for JC1, JC2, and HY1, JC1 was studied in more detail. The cells were grown optimally in a mineral medium (pH 6.8) under a gas mixture of 30% CO and 70% air at $30^{\circ}C$. Growth of the cells with CO did not depend on molybdenum. It was able to grow with 100 ppm of CO in air as a sole source of carbon and energy.