• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.511-516
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• 1994

P multocida was isolated from 80(17.7%) of 450 pneumonic lungs of slaughter pigs. The majority of the biochemical and cultural characteristics of P multocida isolates were identical to those of the reference strains employed. Seventy seven strains(96.3%) among 80 isolates were capsular serotype A while the remaining 3(3.8%) were serotype D. All isolates were very susceptible to ampicillin, ceftiofur, cephalothin, ciprofloxacin and penicillin-G although some of them were resistant to sulfamethoxin and/or streptomycin. Sixty one(76.3%) of all 80 P multocida isolates were dermonecrotic toxin producers. Out of 77 isolates of serotype A and 3 isolates of serotype D, 59(76.6%) and 2(66.7%) were toxigenic, respectively. No difference was noted in dermonecrotic toxigenicity of the isolates in relation to capsular serotypes.

• Restorative Dentistry and Endodontics
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• v.9 no.1
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• pp.89-99
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• 1983

The rational approach to antimicrobial therapy of infected root canals is based on accurate identification of the infecting organism and on the organism's susceptibility to antimicrobial agents as measured by standardized techniques. In establishing criteria for the selection of antibiotics, a susceptibility test should be performed. The purpose of this study was to investigate the susceptibility of 224 aerobic and anaerobic microbial strains isolated from infected root canals to various antibiotics. This was performed by using 7 antibiotic sensi-disc: Penicillin (10 units), Ampicillin (10 mcg), Tetracycline (30 mcg), Streptomycin (10 mcg), Kanamycin (30 mcg), Lincomycin (2 mcg), and Clindamycin (2 mcg). The results were as follows; 1. Strains isolated from infected root canals was shown to be most susceptible to Clindamycin, while Streptomycin exhibited least antibacterial properties. 2. Anaerobes were found to be susceptible to Penicillin, Ampicillin, and Clindamycin. 3. Streptomycin and Kanamycin were shown to be effective against Staphylococcus aureus and Staphylococcus epidermis, however, unidentified G(+) cocci organisms were found to be resistant to these agents. 4. Bifidobacterium sp. was susceptible to Lincomycin while G(+) rods were resistant to it. 5. Staphylococcus aureus, Micrococcus sp., and anaerobes were highly susceptible to Clindamycin. 6. All of the antibiotics tested were shown to be very effective against Eubacterium sp.

• Microbiology and Biotechnology Letters
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• v.3 no.1
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• pp.7-15
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• 1975

The possibilities of utilizing acid-hydrolyzate of "Sliced and dried sweet potatoes" as a carbon source for the microbial production of L-Glutamic Acid(L-GA) with Micrococcus glutamicus were investigated and the results showed as follows： 1) The highest hydrolysis rate, 74.6% of the reducing sugar based on the weight of dry matter, was obtained when the sweet potatoes were hydrolyzed with 0.8% of HCI at 2.0kg/$cm^2$ for 30 minutes. The most favorable hydrolyzate for the growth of the cells, however, was found to be the one obtained by treating the sweet potatoes with 0.5% HCI at 2. 0kg/$cm^2$ for 10 minutes. Reducing sugar content of the hydrolyzate was 10% as glucose. 2) Biotin content of the hydrolyzate was 25$\mug$/1 and it was proved to be excess in amount for the L-GA production. 3) The effects of addition of antibiotics, alcohols and fatty acid esters on the L-GA production were tested in the biotin excess medium. The production of L-GA was most increased to 32.5g/l with the addition of 10 I. U. of penicillin per ml. to the culture medium at 4 hours after inoculation. But the addition of alcohols, especially fatty acid esters, showed no significant effects. 4) Among the organic nutrients tested. " Gluten acid hydrolyzate" greatly enhanced the production of L-GA adding it＇s concentration of 1.0% to the medium. 5) The maximum production of L-GA resulted in 35g/1 when the cells were grown for 48 hours in the hydrolyzate medium supplemented with 1.0% of "Gluten acid hydrolyfate" and with 10 I. U. of penicillin per ml added at 4 hours after cultivation.

• Microbiology and Biotechnology Letters
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• v.2 no.3
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• pp.141-147
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• 1974

The cultural conditions for L-glutamate production were investigated using Brevibacterium flavum nov. sp. D2209B, the most productive strain among 5 strains reported in preceeding paper. A temperature of 3$0^{\circ}C$ and a medium volume of 30 ml per 500-flask were selected as standard culture conditions. And the following results were obtained. 1. When the concentration of acetate in the medium was below 30 g per litre, the maximum amount of L-glutamate was accumulated. 2. KH$_2$PO$_4$, MgSO$_4$, FeCI$_3$ and MnCI$_2$ were required for the L-glutamate poduction, but the concentration of those inorganic salts little effected. 3. Signifcant amount of L-glutamate was accutnulated in the limited biotin concentration less than 0.3 ug per litre. 4. The addition of malic acid or succinic acid enhanced the accumulation. 5. The L-glutamate accumulation was related to the incubation time of seed; the amount of L-glutamate accumulated was maximum by inoculating 16-20 hour incubated seed. 6. In the medium containing sufficient amount of biotin for growth, L-glutamate accumulation was stimulated by the addition of penicillin at appropreate time during incubation.

• Applied Biological Chemistry
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• v.36 no.1
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• pp.11-16
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• 1993

A bacteria strain producing extracellular protein was isolated and identified from soil samples, and the optimum conditions of producing protein were investigated. Eleven strains of bacteria were isolated from soil samples. Among which WY-60 strain showed a very strong capability of producing protein and identified as a Bacillus sp. The optimum composition of nutrient medium for the production of the protein by WY-60 was fructose 4.0%, polypeptone 1.0%, $NH_4NO_3$ 0.1%, $K_2HPO_4$ 0.1%, $MgSO_4{\cdot}7H_2O$ 0.005%, $CaCO_3$ 1.0% and the optimum pH and temperature were 8.0 and $30^{\circ}C$, respectively. The penicillin G and lincomycin added to the above medium were effective for the protein production of the WY-60, but other antibiotics were non-effective. The maximum production of protein was obtained after 5 days culture.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.2
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• pp.185-192
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• 2016

Ampicillin, a ${\beta}$-lactam antibiotic, dose-dependently protects neurons against ischemic brain injury. The present study was performed to investigate the neuroprotective mechanism of ampicillin in a mouse model of transient global forebrain ischemia. Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral common carotid artery occlusion for 40 min. Before transient forebrain ischemia, ampicillin (200 mg/kg, intraperitoneally [i.p.]) or penicillin G (6,000 U/kg or 20,000 U/kg, i.p.) was administered daily for 5 days. The pretreatment with ampicillin but not with penicillin G significantly attenuated neuronal damage in the hippocampal CA1 subfield. Mechanistically, the increased activity of matrix metalloproteinases (MMPs) following forebrain ischemia was also attenuated by ampicillin treatment. In addition, the ampicillin treatment reversed increased immunoreactivities to glial fibrillary acidic protein and isolectin B4, markers of astrocytes and microglia, respectively. Furthermore, the ampicillin treatment significantly increased the level of glutamate transporter-1, and dihydrokainic acid (DHK, 10 mg/kg, i.p.), an inhibitor of glutamate transporter-1 (GLT-1), reversed the neuroprotective effect of ampicillin. Taken together, these data indicate that ampicillin provides neuroprotection against ischemia-reperfusion brain injury, possibly through inducing the GLT-1 protein and inhibiting the activity of MMP in the mouse hippocampus.

• Journal of Life Science
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• v.25 no.1
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• pp.29-36
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• 2015

Prodigiosin, a member of natural red pigment family, is produced by Serratia marcescens, and characterized by a common pyrrolylpyrromethane skeleton. This pigment has been reported with the effects of anticancer, immunosuppressant, antifungal, and algicidal activities. Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of hospital infections. In this study, anti-MRSA properties of prodigiosin isolated from Serratia sp. PDGS 120915 were investigated. We identified and purified prodigiosin using high performance liquid chromatography (HPLC) and evaluated anti-MRSA activity. Purified prodigiosin inhibited the growth of MRSA. The minimum inhibitory concentrations (MICs) of prodigiosin were determined to $32{\mu}g/ml$ against the MRSA strains. Fractional inhibitory concentration (FIC) indices of ampicillin and penicillin were indicated synergistic effects of prodigiosin on MRSA.

• Analytical Science and Technology
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• v.23 no.2
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• pp.119-127
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• 2010

An effective method for the simultaneous analysis of ${\beta}$-lactams from surface water was established. After solid-phase extraction with HLB (Hydrophilic Lipohilic Balance) cartridge at pH 2, seven ${\beta}$-lactams (amoxicillin, ampicillin, penicillin G, cefaclor, cefadroxil, cefatrizine and cephradine) were determined using LC/ESI-MS/MS. In this newly established method, correlation coefficients ($r^2$) of calibration curves for seven ${\beta}$-lactams in blank surface water appeared to be 0.9911~0.9995 in the concentration range of 0.01~1.0 ng/mL. The limits of detection (LODs) and the limits of quantificaiton (LOQs) in spiked surface water were shown to be 0.0003~0.0234 ng/mL and 0.0046~0.0778 ng/mL, respectively. The developed method is believed to serve as a rapid and reliable method for the qualitative and quantitative analysis of residual ${\beta}$-lactam antibiotics from aquatic environment.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.165-169
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• 2006

A Citrobacter sp. MB 2, azo dyes decolorizing bacterium, was isolated from the wastewater and soil and identified as Citrobacter sp.. It was examined that optimum conditions for culture media were 0.5% of sucrose, 1.0% of yeast extract, 0.1% of $K_2HPO_4$, 0.1% of $NaHCO_3$ per distilled water. The best efficient condition of culture was obtained at pH 7.0, $30^{\circ}C$ and aerobic shaking culture. The number of Citrobacter sp. MB2 in optimum medium was increased more than 7 fold compared to basal medium and 50 fold compared to nutrient broth. This strain was exhibited strong resistance against metal salts and antibiotics (ampicillin and penicillin G).

• Food Science of Animal Resources
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• v.41 no.2
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• pp.324-334
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• 2021

This study aimed at determining the genetic and virulence characteristics of the Listeria monocytogenes from smoked ducks. L. monocytogenes was isolated by plating, and the isolated colonies were identified by PCR. All the obtained seven L. monocytogenes isolates possessed the virulence genes (inlA, inlB, plcB, and hlyA) and a 385 bp actA amplicon. The L. monocytogenes isolates (SMFM2018 SD 1-1, SMFM 2018 SD 4-1, SMFM 2018 SD 4-2, SMFM 2018 SD 5-2, SMFM 2018 SD 5-3, SMFM 2018 SD 6-2, and SMFM 2018 SD 7-1) were inoculated in tryptic soy broth (TSB) containing 0.6% yeast extract at 60℃, followed by cell counting on tryptic soy agar (TSA) containing 0.6% yeast extract at 0, 2, 5, 8, and 10 min. We identified five heat resistant isolates compared to the standard strain (L. monocytogenes ATCC13932), among which three exhibited the serotype 1/2b and D-values of 5.41, 6.48, and 6.71, respectively at 60℃. The optical densities of the cultures were regulated to a 0.5 McFarland standard to assess resistance against nine antibiotics after an incubation at 30℃ for 24 h. All isolates were penicillin G resistant, possessing the virulence genes (inlA, inlB, plcB, and hlyA) and the 385-bp actA amplicon, moreover, three isolates showed clindamycin resistance. In conclusion, this study allowed us to characterize L. monocytogenes isolates from smoked ducks, exhibiting clindamycin and penicillin G resistance, along with the 385-bp actA amplicon, representing higher invasion efficiency than the 268-bp actA, and the higher heat resistance serotype 1/2b.