• 한국동물위생학회지
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• 제32권1호
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• pp.93-102
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• 2009

In this study, antimicrobial resistance of E. coli isolated from domestic beef on sale in Busan and Gyeongnam province was investigated from March to October 2008. A total of 400 beef samples were collected for the monitoring of antimicrobial resistance, and 39 (9.8%) strains of E. coli were isolated. Antimicrobial resistance test was carried out by agar disc diffusion method with 17 antimicrobials. In general, E. coli isolates showed the highest antimicrobial resistance to tetracycline (85.3%), followed by doxycycline (76.5%), streptomycin (61.8%) and sulfamethoxazole/trimethoprim (61.8%). Then they showed higher resistance to several antimicrobials like kanamycin and neomycin (55.9%). However, They had low antimicrobial resistance to amikacin (8.8%), amoxicillin/clavulanic acid (2.9%). Of 39 isolates, 31 (79.5%) were resistant to more than 2 antimicrobials. Among 17 antimicrobials examined, tetracyclines were the most resistant, followed by aminoglycosides, sulfonamides. The resistance was seemed to be correlated to amounts of antimicrobial use. In the result of this study, we suggest that there be need to regulate the abuse of antimicrobial on food-producing animals in Korea because the concern on antimicrobial resistant is gradually increased worldwide.

• 한국축산식품학회지
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• 제30권2호
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• pp.223-231
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• 2010

In order to develop a new starter for fermented milk, Lactobacillus paracasei subsp. paracasei BFI46 (BFI46) obtained from new-born infant feces was investigated for physiological characteristics. Good immunomodulating activity was evident compared with commercial lactic acid bacteria starter cultures. The optimum growth temperature of BFI46 was $40^{\circ}C$ with 12 h required to reach pH 4.3. Testing with 13 different antibiotics revealed greatest sensitivity of BFI46 to penicillin- G and chloramphenicol, and heightened resistance to neomycin, kanamycin and polymyxin. BFI46 displayed higher esterase activities compared to 18 other enzymes, was comparatively tolerant to bile juice and able to survive at pH 2 for 3 h, and displayed high resistance against Escherichia coli and Salmonella Typhimurium with a survival rate of 57.14% and 96.36%, respectively. The results indicate that BFI46 could be an excellent starter culture for fermented milk with high level of immunomodulating activity.

• 대한피부과학회지
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• 제56권10호
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• pp.624-627
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• 2018

Allergic contact dermatitis is an inflammatory condition associated with periorbital erythema, edema, and pruritus. The periorbital skin is relatively thin compared with the skin over other facial areas; therefore, it is vulnerable to allergen penetration and may show a variety of cutaneous manifestations. Recently, vision enhancement surgery is a widely performed procedure, and the prevalence of senile cataract and glaucoma is increasing. The prevalence of periocular allergic contact dermatitis is increasing secondary to the growing use of topical ophthalmic medications. Several studies in Korea have reported periocular allergic contact dermatitis secondary to the use of topical ophthalmic medications including latanoprost ($Latano^{(R)}$), fluorometholone ($Tolon^{(R)}$), polymyxin B ($Terramycin^{(R)}$), atropine sulfate ($Atropine^{(R)}$), neomycin sulfate ($Cambison^{(R)}$), and befunolol hydrochloride ($Bentos^{(R)}$), among others. However, ofloxacin ($Effexin^{(R)})$-induced allergic contact dermatitis has not been reported in the domestic and/or foreign literature. We report a case of periocular allergic contact dermatitis secondary to the use of ofloxacin ophthalmic ointment.

• 한국미생물·생명공학회지
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• 제48권4호
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• pp.429-438
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• 2020

The emergence of multi-drug resistant, pathogenic methicillin-resistant Staphylococcus aureus (MRSA) is a threat to global health and has created a need for novel functional therapeutic agents. In this study, we evaluated the underlying mechanisms of the anti-MRSA effect of an azaphilone pigment, sclerotiorin (SCL) from Penicillium sclerotiorum. The antimicrobial activity of SCL was evaluated using agar disc diffusion, broth microdilution, time-kill assays and biophysical studies. SCL exhibits selective activity against Gram positive bacteria including MRSA (range, MIC = 128-1028 ㎍/ml) and exhibited rapid bactericidal action against MRSA with a > 4 log reduction in colony forming units within three hours of administration. Biophysical studies, using fluorescent probes and laser or electron microscopy, demonstrated a SCL dose-dependent alternation in membrane potential (62.6 ± 5.0.4% inhibition) and integrity (> 95 ± 2.3%), and the release of UV260 absorbing materials within 60 min (up to 3.2 fold increase, p < 0.01) of exposure. Further, SCL localized to the cytoplasm and hydrolyzed plasmid DNA. While in vitro checkerboard studies revealed that SCL potentiated the antimicrobial activity of topical antimicrobials such as polymixin, neomycin, and bacitracin (Fractional Inhibitory Concentration Index range, 0.26-0.37). Taken together these results suggest that SCL targets the membrane and DNA of MRSA to facilitate its anti-MRSA antimicrobial effect.

• Journal of Dairy Science and Biotechnology
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• 제41권4호
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• pp.211-218
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• 2023

This study aimed to identify lactic acid bacteria isolated from eight fermented milk products in Iran. We enumerated Lactobacillus species using De Man-Rogosa-Sharpe (MRS)-maltose and MRS agar with pH adjusted to 5.2, as well as assessment at 37℃ for 48 hr, studied Streptococcus spp. using M17 agar at 43℃ for 24 hr, and assessed Bifidobacterium species using nalidixic acid, paromomycin sulfate, neomycin sulfate, and lithium chloride (BL-NPNL) agar at 37℃ for 48 hr. The total viable Streptococcus spp. cell in fermented milk varied at 4.73-8.83 log CFU/mL. However, Bifidobacterium spp. were not detected in any of the tested samples. Lactobacilli were not detected in four of the eight samples, and viable Lactobacilli cells in the remaining four samples ranged 2.48-3.85 log CFU/mL. The pH of the tested samples ranged 3.53-4.19, and soluble solids (Brix measurement) ranged 7.5%-17.9%. A total of 130 isolates of gram-positive catalase-positive bacteria were characterized at the species level using 16S rRNA sequencing. Sequence analysis identified six species: Streptococcus thermophilus, Lactobacillus delbrueckii subsp. sunkii, Lactobacillus delbrueckii subsp. indicus, Lactiplantibacillus plantarum, Lacticaseibacillus rhamnosus, and Levilactobacillus brevis.

• Current Research on Agriculture and Life Sciences
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• 제11권
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• pp.11-17
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• 1993

완두에 있어서 보다 효율적인 형질전환 방법을 모색하고 형질전환된 개체를 얻고자 본 실험을 수행하여 얻어진 결과는 다음과 같다. 형질전환은 발아중인 완두의 생장점(shoot tip)을 제거한 다음 T-DNA내에 GUS gene과 neomycin phosphotransferase II gene이 들어있는 binary vector를 가진 Agrobacterium tumefaciens를 생장점을 제거한 부위에 감염시켰다. 감염 후 새로 형성된 shoot는 개체당 4~5개였으며, 그중 GUS유전자가 발현하는 shoot만을 정상적인 식물체로 분화 시켰다. 감염부위에서 형성된 shoot에서의 GUS유전자의 발현빈도는 10%내외였다. 이들 개체로 부터 genomic DNA를 분리하여 Dot blot hybridization분석 결과 T-DNA가 식물체 내에 존재함을 알 수 있었고, 수확한 종자를 발아시켜 Sorthern blot hybridization한 결과 T-DNA가 다음세대로 전달되었음이 확인되었으며 형질전환율은 2%이내였다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권10호
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• pp.1390-1394
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• 2004

We have achieved efficient transformation system for forage-type tall fescue plants by Agrobacterium tumefaciens. Mature seed-derived embryogenic calli were infected and co-cultivated with each of three A. tumefaciens strains, all of which harbored a standard binary vector pIG121Hm encoding the neomycin phosphotransferase II (NPTII), hygromycin phosphotransferase (HPT) and intron-containing $\beta$-glucuronidase (intron-GUS) genes in the T-DNA region. Transformation efficiency was influenced by the A. tumefaciens strain, addition of the phenolic compound acetosyringone and duration of vacuum treatment. Of the three A. tumefaciens strains tested, EHA101/pIG121Hm was found to be most effective followed by GV3101/pIG121Hm and LBA4404/pIG121Hm for transient GUS expression after 3 days co-cultivation. Inclusion of 100 $\mu$M acetosyringone in both the inoculation and co-cultivation media lead to an improvement in transient GUS expression observed in targeted calli. Vacuum treatment during infection of calli with A. tumefaciens strains increased transformation efficiency. The highest stable transformation efficiency of transgenic plants was obtained when mature seed-derived calli infected with A. tumefaciens EHA101/pIG121Hm in the presence of 100 $\mu$M acetosyringone and vacuum treatment for 30 min. Southern blot analysis indicated integration of the transgene into the genome of tall fescue. The transformation system developed in this study would be useful for Agrobacterium-mediated genetic transformation of tall fescue plants with genes of agronomic importance.

• Asian-Australasian Journal of Animal Sciences
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• 제24권5호
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• pp.643-649
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• 2011

The objective of this study was to determine the effect of feeding direct-fed microbials (DFM) on the growth performance and prophylaxis of calf diarrhea during the pre-weaning period as an alternative to antibiotics. A multi-species DFM was formulated including three lactic acid bacteria (Lactobacillus salivarius Ls29, Pediococcus acidilactia Pa175, and L. plantarum Lp177), three Bacillus strains (B. subtilis T4, B. polymyxa T1 and SM2), one yeast, Saccharomyces boulardii, and a nonpathogenic E. coli Nissle 1917. Lactic acid bacteria and Bacillus strains were selected based on the antibacterial activity against various animal pathogens, especially pathogenic E. coli using agar diffusion methods in vitro. Test and control groups were fed milk replacer and calf starter supplemented with DFM ($10^9$ cfu each of eight species/d/head, n = 29) or with antibiotics (0.1% neomycin sulfate in milk replacer and Colistin 0.08% and Oxyneo 110/110 0.1% in calf starter, n = 15), respectively. Overall fecal score and the incidence rate of diarrhea were reduced in the DFM group compared to the antibiotics one. About 40% of calves in antibiotic group suffered from diarrhea while in DFM group only 14% showed diarrhea. There was no difference in the average daily gain and feed efficiency of two groups. The hematological levels of calves were all within the normal range with no significant difference. In conclusion, the feeding of multispecies DFM during the pre-weaning period could reduce calf diarrhea and there was no difference in the growth performance between the groups, thus showing the potential as an alternative to antibiotics.

• 한국축산식품학회지
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• 제30권1호
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• pp.154-162
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• 2010

This study was carried out to compare the efficacy and selectivity of TOS and BS media for enumeration of bifidobacteria in commercial fermented milk products. First, bifidobacteria was isolated from 20 fermented milk products, and all isolated bifidobacteria were identified by genomic technology as Bifidobacterium lactis. The two media significantly differed from each other with regard to the recovery of B. lactis, that is, the recovery of this organism was as much as 6 logs lower on BS medium than on TOS. When the concentration of BS solution (mixture of paromomycin sulfate, neomycin, sodium propionate, and lithium chloride) used in BS medium was reduced to 50% (BS50), a relatively high percentage recovery of bifidobacteria from pure cultures was achieved. Susceptibility tests to antibiotics and tests for selective agents for the isolated bifidobacteria and lactic acid bacteria were conducted. The BS solution inhibited some lactic acid bacteria and Bifidobacterium species, while mupirocin (MU) suppressed the growth of all tested lactic acid bacteria but not Bifidobacterium. As compared with BS50 medium, TOS with or without MU showed good bifidobacteria recovery and readily distinguishable colonies; in particular, TOS supplemented with MU had a high selectivity for bifidobacteria. In conclusion, all results suggested that TOS medium with or without MU was found to be suitable for selective enumeration of bifidobacteria from mixed cultures in fermented milk, and better in that capacity than BS medium.

• 한국식품위생안전성학회지
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• 제9권3호
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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%)