• Journal of fish pathology
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• v.4 no.2
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• pp.71-77
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• 1991

From August to October of 1991, a bacterial disease occurred in cultured flounder, of 0 age Paralichthys olivaceus, in Cheju-do. Typical symptoms of the diseased fish were the hemorrage of the opercle, discoloration of the body, exophthalmus and hemorrhage of the eyes. The causative organism isolated from diseased fish was identified as a $\beta$-hemolytic Streptococcus. This bacterium was not identical with any known Streptococcus species listed in Bergey's Manual of Determinative Bacteriology 8th edition. However there was a close similarity between this species and Streptococcus sp. isolated from flounder and reported by Tashio (1983). The isolated bacteria streptococcus sp. showed very high sensitivity to the SM and EM, however, it resisted to the high concentration of Penicillin. In the pathagenicity analysis, about $1.1{\times}10^9$, $1.1{\times}10^7$, $1.1{\times}10^5$, $1.1{\times}10^3$, $1.1{\times}10^1cells$/100g B.W of isolated bacteria were injected percutaneouly. The results showed that this inoculation size $1.1{\times}10^3cells$/100g B.W was the threshold for the induction of mortality in pathogenicity analysis.

• Journal of fish pathology
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• v.14 no.2
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• pp.71-80
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• 2001

The purpose of this study was to investigate the microbiological characteristics and the distributions of the bacteria causing streptococcicosis occurred in marine fish farm, Korea. Many kinds of cultures fishes suffered from the disease accompanied with typical symptoms, including darkening of the skin, exophthalmia, petechiae inside of the opercula and distended abdomen. The isolates from the diseased fishes were compared with Lactococcus garvieae by biochmical, biophysical and serological methods and polymerase chain reaction(PCR) assay. We isolated 35 strains of the geuns Streptococcus from the diseased olive flounder, Paralichthys olivaceus, yellow tail, Seriola quinqueradiata and Korean rockfish, Sebastes schlegeli. 15 strains out of the isolates were identified to L. garvieae and the others were not because of their different biochemical and biophysical charateristics. Seven strains of the isolates were agglutinated by rabbit serum raised against L. garvieae $KG^+$ phenotypic cells(ATCC49156)as a reference strain. Twenty-one strains of the isolates identified to L. garvieae since they were formed the expected band through performing PCR assay using specific primers, pLG-1(5'-CATAACAATGAGATCGC-3') and pLG-2(5'-GCACCCCGCGGTTG-3'). In the present study, it showed that L. garvieae was a dominant strain causing streptococcicosis in the tested area due to occurrence of 21 strains as L. garvieae out of all the isolates, 9 atrains as Streptococcus sp. and 5 strains as Enterococcus sp.

• The Journal of the Korean dental association
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• v.9 no.12
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• pp.807-811
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• 1971

This report was concerned with the isolation and identification of bacterial flora in the human dental plaque and the dextransucrase activity of isolated species. The results were obtained as follows: 1. The bacterial flora, isolated from the human dental plaque, was identified as 3 species of resembling streptococci, Streptococcus salivarius strain SD-1, Streptococcus bacilli, Lactobacillus brevis strain SD-3, Lactobacillus acidophilus strain SD-2 and SD-7, resembling Staphylococcus sp, and one species of resembling Leuconostoc mesenteroides strain SD-6. 2. The dextransucrase activites of resembling Streptococcus mitis strain SD-9 and Streptococcus salivarius strain SD-1 were exhibited the highest among the isolated species of human dental plaque.

• Journal of Microbiology and Biotechnology
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• v.7 no.2
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• pp.101-106
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• 1997

Strain improvement for the enhanced production of streptokinase and streptodornase in Streptococcus sp. ATCC 12449 was performed. Strain UB111, a hyperproductive mutant which was isolated by use of nitrosoguanidine and selection of colonies with large clear zones on DNase test agar plates supplemented with $1{\%}$ glucose and $0.5{\%}$ ammonium chloride, produced about 3 fold more streptokinase and streptodornase than the wild type when tested in shake flask fermentations. The enhanced production of both streptokinase and streptodornase was achieved by cultivating the mutant in a pH-controlled fermentor containing fermentation medium enriched with yeast extract ($2.1{\%}$). Under these conditions, the mutant produced 7300 units/ml of streptokinase and 800 units/ml of streptodornase.

• Journal of Microbiology and Biotechnology
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• v.6 no.4
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• pp.265-269
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• 1996

An isolate of Streptomyces rochei synonym was found to produce antibiotics with narrow anti-microbial spectrum against Streptococcus and Xanthomonas sp. Among the antibiotic complex produced by the strain, the main active compound was isolated, and its physico-chemical properties and biological activities were investigated. Molecular weight of the compound was determined to be ${[M+H]}^+$ 797 (FAB-MS). UV, $^1H \;and\;^{13}C$ NMR, and IR spectra suggested that the compound is a kirromycin-like aurodox group antibiotic. However, the anti-microbial spectrum of the main compound was slightly different from that of kirromycin. In addition, it was newly found that kirromycin showed a selective anti-microbial activity against Streptococcus pyogenes and phytopathogenic Xanthomonas sp.

• Applied Biological Chemistry
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• v.31 no.1
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• pp.33-37
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• 1988

Three species of Pediococci, Pediococcus pentosaceus, Pediococcus acidilactici and Pediococcus halophilus were isolated from Kimchi. P. pentosaceus and P. acidilactici showed inhibitory activity against Streptococcus faecalis, Pseudomonas sp., P20 and Vibrio parahaemolyticus. However, the growth of all test organisms was not inhibited by P. halophilus. Ten strains contained one to seven plasmids, ranging in size from 1 to 60 megadaltons.

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.222.1-222
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• 1994

No Abstract, See Full Text

• Journal of fish pathology
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• v.18 no.2
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• pp.147-156
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• 2005

To obtain antimicrobial algae against fish pathogenic bacteria, we screened 80% methanolic extracts of 30 algae using fish pathogenic bacteria, Staphylococcus sp., Streptococcus sp., Edwardsiella tarda and Vibrio anguillarum. Among them, Corallina officinalis, Dumontia simplex, Gloipeltis furcata, Grateloupia lanceolata and Grateloupia turuturu were effective for growth inhibition of a Gram-positive bacterium, Staphylococcus sp.. Sargassum thunbergii and Polysiphonia morrowii exhibited significant inhibitory effects against the growth of Gram-negative bacteria, both E. tarda and V. anguillarum. Moreover, antimicrobial activity-guided fractionation for P. morrowii extract yielded significantly active 90% methanolic fraction. This fraction significantly inhibited the growth of E. tarda exhibiting a MIC of 1 mg/ml. In addition, its antimicrobial activity was stable under various pH conditions.

• Journal of fish pathology
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• v.12 no.1
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• pp.42-48
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• 1999

The disinfectant effects of total residual oxidants (TROs) produced by ozonization of natural sea water were investigated against fish pathogenic bacteria isolated from flounder and red seabream. The concentration of 0.1 mg TROs/liter was stable for 20 min in filtered natural seawater, and those of 0.3 and 0.5 mg TROs/liter were also stable for more 1 hr. Disinfectant effects of TRO against Edwardsiella tarda, Vibrio sp., Streptococcus sp. and Staphylococcus sp. were observed with a concentration of 0.1 mg/liter for 180 sec, and the treatment killed more than 99.9% of bacterial cells. With TROs of 0.3 to 0.5 mg/ liter, the viable cells of the bacteria were reduced by more than 99.99% in 60 sec.

• Journal of Veterinary Clinics
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• v.19 no.1
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• pp.19-22
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• 2002

The examination with 96 bacteria isolates for antibiotics susceptibility was resulted in exploring many antibiotics resistance isolates from the diseased fishes. Vibrio sp. isolates were demonstrated over 90% resistances for Penicillin (P), Amoxicillin (Amc), Erythromycin (I), Colistin (CL). Streptomycin (S). Novobiocin (NV) and Neomycin(N), these isolates were, however, appeared over 80% susceptibilities for Norfloxacin (Nor), CE and UB. In Edwardsiella tarda case, 90 to 100% high resistance was observed for P, Doxycycline (Do), Tetracyclin (Te), Oxytetracycline (T), E, CL, Sulfamethoxasoletrimetoprim (SXT), S, Oxolinic acid (OA), W, Neomycin(N), on the contrary, 90 to 100% high susceptibilities was found for Amc, Nor, Ciprofloxacin (Cip), Orbifloxacin (ORB), Enrofloxacin (ENR), Flumeguine (UB) and NA. CL, Pefloxacin (PEF),S, Flumeguine (UB), OA, NA, NV N was exhibited 90 to 100% resistances for Streptococcus sp., on the other hand, 100% susceptible to AMC and 80% susceptible to Do, Te, ENR and UB was recognised. Lastly, Photobacterium damsela subsp. piscicida was showed 100fe susceptible to Amc and 86% susceptible to NOR, CIP ENR and UB. As a consequence, fish bacterial pathogens isolated from Kyeongnam area, especially Tongyeong-si, Geoje-si, and Goseong-gun, were showed highly resistant to a variety of antibiotics available in the field.