• Korean journal of applied entomology
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• v.17 no.1 s.34
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• pp.7-13
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• 1978

Experiments were conducted to study the integrated control of one of the major pests of citrus, the citrus red mite, Panonychus citri (McGregor). Studies were conducted in Seogwipo, Cheju Island, 1973-1976. Results obtained were: 1. The major peak of citrus red mite occurrence was mid-July to mid-August. 2. Standard field populations of citrus red mite were also high in September, October, and November. 3. A total of 10 species of natural enemies of citrus red mite were found. These included; Oligota yasumatusi Kistner, Anystis baccarum L., Hemerobiid sp., Semidalis albate E., Orius sp., Agistemus terminalis Q., 3 species of lady beetles (Coccinellidae), and one unidentified species of predacious mite. 4. Annual occurrence of citrus med mite tended to decrease in unsprayed fields, but increased in fields receiving standard treatments. 5. With fungicides, there was an increase in mite populations associated with use of Bordeaux mixture and copperpowder sprays. Streptomycin, however, did not effect on increase in mite numbers.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1977.06a
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• pp.3.1-3
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• 1977

Now a lot of antibiotics are available for daily clinical use. Streptomycin, above all them, is widely used because of its effects upon tuberculosis. Recently, however, the ototoxic effects of SM was noticed especially on the vestibular sensory organs, so called, SM deafness. The authors have clinically investigated the incidence of SM deafness of 198 cases of admission at Masan National Hospital for treatment of pulmonary tuberculosis. The results obtained were follows; 1. The incidence of SM deafness was 30 cases (15.2%) of total 198 cases. 2. SM deafness had a tendency to increase according to amount of administrated SM dose. 3. The administration of SM 1.0 gm. daily (17.4%) resulted in more frequent incidence than that (2.9%) of 1.0gm. single dose, twice a week. 4. The complication due to SM administration was 59 cases (2.98%). Among them, tinnitus was the most frequent symptom recording 14 cases (46.7%). 5. SM deafness had a tendency to begin with high frequency and than progress gradually to speech range. 6. As concern of type of audiogram, gradual descending type (40.0%) and horizontal type(30.3%) were the most frequent.

• Microbiology and Biotechnology Letters
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• v.10 no.4
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• pp.289-295
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• 1982

Streptomyces bobili (YS-40) isolated from soil was tested that it had drug resistance against penicillin, cephalosporin series antibiotics and other antibiotics in the previous paper. The treatment of Streptomyces bobili, (YS-40) with ethidium bromide (EtBr), acriflavine and sodium dodecyl sulfate. (SDS) resulted in the elimination of R-plasmid from the host strain. Minimum growth inhibitory concentrations (MIC) of Hg, Ag, penicillin-G, ampicillin, chloramphenicol, oxytetracycline, streptomycin and kanamycin were found to be 15, 10, > 3, 000, > 100, > 1, 000, > 100, < 5 and < 5$\mu\textrm{g}$/$m\ell$ respectively. Among the curing agents, EtBr was proved to be the most powerful compound for the elimination of R-plasmid in the strain and the elimination rate with EtBr(10$\mu\textrm{g}$/$m\ell$) was about 98%. Optimal pH to. the elimination of R-plasmid was pH 7.0 and the R-plasmid in the cells incubated for 24 hrs was proved to be eliminated most effectively. Aerial mass color, soluble pigment formation and reverse side color were reported to be often the plasmid associated characteristics of the R-plasmid bearing bacteria. But these characteristics of the uncured and cured Streptomyces bobili, (YS-40) showed no changes in the most of the pigment formation media tested in this work.

• Journal of Veterinary Clinics
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• v.4 no.1
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• pp.409-421
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• 1987

For the epidemiological studies of the respiratory infection from 1,918 heads of adult rabbits from January 1980 to December 1985 at an integrated farm, the causative agents were. Isolated samples 92 from of lungs and nasal discharges, and identified by serological and non-serololgical tests, the loss rates by the infection were also investigatyed, and the antimicrobial sensitivities of the isolates were determined. The results obtained were as fellows : 1. The loss rate by respiratory infection was 11.9% among 1,819 heads which raised and 41.7% among 518 heads which lost by diseases, and the rate increased annually. 2. The loss rate of rabbits in Spring (45.0%), Summer (45.5%) and Winter (53.5%) showed significantly higher (P < 0.01) than that in Autumn(29.1%). 3. The loss rate of Rex (56.3%) showed significantly higher (P<0.05) than New Zealand White (40.7%) and Californian (42.0% ). 4. P. multocida.(37.9%), B. brouchiseptica (16.0%), E. coli (10.6%) and so forth were isolated from 92 samples of lungs and nasal discharges. 5. Sixty fours trains of P. multocida were typed by serological or non-serological tests and their all serotypes were A type (62 strains) except 2 strains of untypable. 6. In antimicrobial sensitivity test for 64 isolates of P. multocida, all the strains tested were highly sensitive to chloramphenicol(95.3%), colistin (95.3%), gentamicin (92.2%), kanamycin (90.6%), neomycin (82.8%) and tetracycline (81.3%), but exhibited low sensitivity to streptomycin (26.6%), and all strains were resistant to lincomycin. 7 Twenty seven isolates of B. brouchiseptica showed higher sensitivity to cephalothin (100%), erythromycin (100% ), gentamicin (100%). trimethoprim+sulfamethoxazole (100%), chloramphenicol(88.9%), kanamycin(88.9%), neomycin (88.9%) and colistin (85.2%), but lower sensitivity to nitrofurantoin (18.5%), penicillin(18.5%). streptomycin(18.5%) and ampicillin (14.8%), and all strains were resistant to lincomycin.

• Korean Journal of Microbiology
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• v.8 no.1
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• pp.41-51
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• 1970

In previous paper, it was reported that antibiotic substance such as tetracycline and streptomycin were produced by S'. albus subsp. and S'. globosus. And increase of mycelial growth of two strains, antibiotic production, and changes of pH range are extended to approximately 110-130 hrs in fermenting medium, there-after they decreased with culture period exception of pH range. Two Streptomyces spp. required commonly 4-5% starch as carbon sources and 1.5-2.0% soybean meal as nitrogen sources. However, 0.005-0.01M potassium phosphate dibasic, calcium carbonate (6mg/ml in S.albus subsp. and 2mg/ml in S. globosus), 0.01-0.03M, magnesium sulgate and 0.01M ferric chloride showed as optimal concentration for the growth of 2 strains. Mineral compoments such as zinc, manganese, cobalt, sodium and copper at the level of 10$^{-4}$ -10$^{-6}$ M were observed. Especially, zinc ion showed toxicity to the growth of 2 strains at 0.005M. In relation with pH, there is a little difference in mycelial growth with cultural initial pH.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.24-31
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• 1986

The optimal conditions for the formation and the regeneration of Pseudomonas spheroplast were measured. Pseudomonas spp. cells were transformed to spheroplasts from 99.0% to 99.9% by treatment of $100{\mu}g/ml$ lysozyme and 10mM EDTA at room temperature. The optimal pH for the spheroplast formation was pH 8.0. Magnecium chloride, calcium chloride and streptomycin were effective on the stabilization of Pseudomonas spheroplast, while $Mg^+\;and\;Na^+$ ions were effective on the formation of Pseudonomas spheroplast. Rich Regeneration Medium was used for the regeneration of Pseudonomas spheroplast. To improve regeneration frequency, Bovin Serum Albumine and cationic ions were added to the spheroplast dilution beffer and regeneration environment respectively. Treatment of 20mM calcium chloride in ehr Rich Regeneration Medium could improve the yield of regenerants as much as 28-fold. Treatment of 1% Bovin Serum Albumine in the spgeroplast formation and dilution buffer increased the yield of regenerants to 10-fold. Also, the regeneration frequency was improved to 14-fold shen Rich Regeneration Meidum containing 0.5% Gelatin was used for regeneration as well as 1% Bovin Serum Albumine.

• The Plant Pathology Journal
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• v.38 no.4
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• pp.334-344
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• 2022

Bacterial wilt is a re-emerging disease on dry bean and can affect many other crop species within the Fabaceae. The causal agent, Curtobacterium flaccumfaciens pv. flaccumfaciens (CFF), is a small, Gram-positive, rod-shaped bacterium that is seed-transmitted. Infections in the host become systemic, leading to wilting and economic loss. Clean seed programs and bactericidal seed treatments are two critical management tools. This study characterizes the efficacies of five bactericidal chemicals against CFF. It was hypothesized that this bacterium was capable of forming biofilms, and that the cells within biofilms would be more tolerant to bactericidal treatments. The minimum biocide eradication concentration assay protocol was used to grow CFF biofilms, expose the biofilms to bactericides, and enumerate survivors compared to a non-treated control (water). Streptomycin and oxysilver bisulfate had EC95 values at the lowest concentrations and are likely the best candidates for seed treatment products for controlling seed-borne bacterial wilt of bean. The results showed that CFF formed biofilms during at least two phases of the bacterial wilt disease cycle, and the biofilms were much more difficult to eradicate than their planktonic counterparts. Overall, biofilm formation by CFF is an important part of the bacterial wilt disease cycle in dry edible bean and antibiofilm bactericides such as streptomycin and oxysilver bisulfate may be best suited for use in disease management.

• Journal of Microbiology and Biotechnology
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• v.32 no.9
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• pp.1195-1208
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• 2022

Silver nanoparticles (AgNPs) have potential applications in medicine, photocatalysis, agriculture, and cosmetic fields due to their unique physicochemical properties and strong antimicrobial activity. Here, AgNPs were synthesized using actinobacterial SL19 strain, isolated from acidic forest soil in Poland, and confirmed by UV-vis and FTIR spectroscopy, TEM, and zeta potential analysis. The AgNPs were polydispersed, stable, spherical, and small, with an average size of 23 nm. The FTIR study revealed the presence of bonds characteristic of proteins that cover nanoparticles. These proteins were then studied by using liquid chromatography with tandem mass spectrometry (LC-MS/MS) and identified with the highest similarity to hypothetical protein and porin with molecular masses equal to 41 and 38 kDa, respectively. Our AgNPs exhibited remarkable antibacterial activity against Escherichia coli and Pseudomonas aeruginosa. The combined, synergistic action of these synthesized AgNPs with commercial antibiotics (ampicillin, kanamycin, streptomycin, and tetracycline) enabled dose reductions in both components and increased their antimicrobial efficacy, especially in the case of streptomycin and tetracycline. Furthermore, the in vitro activity of the AgNPs on human cancer cell lines (MCF-7, A375, A549, and HepG2) showed cancer-specific sensitivity, while the genotoxic activity was evaluated by Ames assay, which revealed a lack of mutagenicity on the part of nanoparticles in Salmonella Typhimurium TA98 strain. We also studied the impact of the AgNPs on the catalytic and photocatalytic degradation of methyl orange (MO). The decomposition of MO was observed by a decrease in intensity of absorbance within time. The results of our study proved the easy, fast, and efficient synthesis of AgNPs using acidophilic actinomycete SL19 strain and demonstrated the remarkable potential of these AgNPs as anticancer and antibacterial agents. However, the properties and activity of such particles can vary by biosynthesized batch.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.413-420
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• 1988

The strain capable of growing on minimal medium containing aniline as a sole source of carbon was isolated from activated sludges and identified as Pseudomonas putida biotype A. The characterizations of the strain were determined. The optimum concentration for growth of the strain was 1-20 mM of aniline. No changes of pH were detected during cultivation. Some metabolic products of biodegradation of aniline were detected after cultivation of the strain on 10 mM aniline for 48 hours. The strain showed to be resistant to streptomycin, tetracycline, trimethoprim, and sulfanilamide. The strain was also capable of utilizing other aromatic compounds related to aniline as a sole source of carbon. One plasmid carried by this strain was detected. The properties of some of the mutant strains treated with mitomycin C were also discussed. The results suggest that separate, regulatory enzyme systems capable of degrading aniline may exist in plasmid DNA.

• Journal of Veterinary Science
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• v.24 no.6
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• pp.82.1-82.12
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• 2023

Background: The current conventional serotyping based on antigen-antisera agglutination could not provide a better understanding of the potential pathogenicity of Salmonella enterica subsp. enterica serovar Brancaster. Surveillance data from Malaysian poultry farms indicated an increase in its presence over the years. Objective: This study aims to investigate the virulence determinants and antimicrobial resistance in S. Brancaster isolated from chickens in Malaysia. Methods: One hundred strains of archived S. Brancaster isolated from chicken cloacal swabs and raw chicken meat from 2017 to 2022 were studied. Two sets of multiplex polymerase chain reaction (PCR) were conducted to identify eight virulence genes associated with pathogenicity in Salmonella (invasion protein gene [invA], Salmonella invasion protein gene [sipB], Salmonella-induced filament gene [sifA], cytolethal-distending toxin B gene [cdtB], Salmonella iron transporter gene [sitC], Salmonella pathogenicity islands gene [spiA], Salmonella plasmid virulence gene [spvB], and inositol phosphate phosphatase gene [sopB]). Antimicrobial susceptibility assessment was conducted by disc diffusion method on nine selected antibiotics for the S. Brancaster isolates. S. Brancaster, with the phenotypic ACSSuT-resistance pattern (ampicillin, chloramphenicol, streptomycin, sulphonamides, and tetracycline), was subjected to PCR to detect the corresponding resistance gene(s). Results: Virulence genes detected in S. Brancaster in this study were invA, sitC, spiA, sipB, sopB, sifA, cdtB, and spvB. A total of 36 antibiogram patterns of S. Brancaster with a high level of multidrug resistance were observed, with ampicillin exhibiting the highest resistance. Over a third of the isolates displayed ACSSuT-resistance, and seven resistance genes (β-lactamase temoneira [bla_TEM], florfenicol/chloramphenicol resistance gene [floR], streptomycin resistance gene [strA], aminoglycoside nucleotidyltransferase gene [ant(3")-Ia], sulfonamides resistance gene [sul-1, sul-2], and tetracycline resistance gene [tetA]) were detected. Conclusion: Multidrug-resistant S. Brancaster from chickens harbored an array of virulence-associated genes similar to other clinically significant and invasive non-typhoidal Salmonella serovars, placing it as another significant foodborne zoonosis.