• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.298-302
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• 2011

Bacterial wilt, caused by Ralstonia, solanacearum, is a very destructive disease to tomato plants (Solanum lycopersicum) in Korea. This study was undertaken to find out the growth inhibitory effect bactericides on bacterial wilt pathogen of streptomycin, oxytetracyclin streptomycin sulfate WP and significantly suppressed the growth of bacterial wilt pathogen. Copper hydroxide WP showed control value of 62.5%. Therefore, it is concluded that the bactericide used in this study showed strong inhibitory effect to tomato bacterial wilt and they can be recommend to control the disease. And also, Copper hydroxide WP may be effective for control of bacterial wilt of tomato in conventional culture, farming without agricultural and organic farming.

• Korean Journal of Pharmacognosy
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• v.31 no.4
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• pp.407-411
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• 2000

Antibacterial activities of magnolol (MGL) and honokiol (HKL) in combination with four representative antibiotics-amoxicillin (AMPC), oxytetracyclin (OTC), gentamicin (GM) and chloramphenicol (CAP)-were evaluated against four bacterial strains. When tested by disk-plate method, five out of eight combinations such as HKL-AMPC, HKL-CAP, MGL- AMPC, MGL-OTC, and MGL-CAP showed additive to synergistic interaction against gram- negative bacterium Salmonella typhimureum. Of these, MGL-AMPC combination turned out to be antagonistic against Sarcina lutea and Bacillus thurungiensis. Against these two grain-positive bacteria, only HKL-GM combination showed additivity to synergism. All the other combinations showed no interactions. Despite these results, however, no synergism was observed in checkerboard titration assay.

• Research in Plant Disease
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• v.16 no.3
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• pp.266-273
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• 2010

Bacterial pustule of soybean (Glycines max) caused by Xanthomonas axonopodis pv. glycines is one of the most prevalent bacterial diseases of soybean. This bacterium shows strong pathogenicity to the plants and distributes throughout Korea. However, no good control measures including bactericides and resistant cultivars are available to control the disease in Korea. Therefore, this study was conducted to develop chemical control method against soybean bacterial pustule. The present study was undertaken to find out the growth inhibitory effect bactericides (8 antibiotics, 2 copper compounds, quinoline, 18 agro-chemicals) on bacterial pustule pathogen. Antibiotics test showed that tetracycline and streptomycin sulfate significantly suppressed the growth of bacterial pustule pathogen. Also, application of oxolinic acid was found to be effective for pathogen inhibition. However, vancomycin, polymyxin B sulfate and copper compounds did not show the positive suppressive effect on growth of the pathogen. Among the eighteen agro-chemicals, streptomycin sulfate + oxytetracyclin (18.8 + 1.5%) WP, oxytetracycline (17%) WP and oxolinic acid (20%) WP were found to be effective for the inhibition of the pathogen in vitro. The selected 5 agro-chemicals were also applied on soybean in field and their control effects against the soybean bacterial pustule were tested. The foliar application of streptomycin sulfate + oytetracyclin WP and oxytetracycline WP on the naturally infected soybean (Taekwangkong) showed high control value (above 70%). Therefore, it is concluded that the bactericides used in this study showed strong inhibitory effect to soybean bacterial pustule and they can be recommend to farmers to control the disease.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.258-265
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• 2009

A study on livestock environment improving agents was conducted; top two brands (A and B) in the market, bottom two brands (E and F) based on market shares and two newly developed agents (C and D) were measured for viable count and tested for resistance towards antibiotics prohibited against livestock feeds. Test results revealed that the measured viable count of agents A and B matched those on the labels were identical; however agent E lacked information on viable counts nor the intended usage, while the measured viable count of agent F was less than the label-stated count. No correlation was found between the antibiotic-resistance test and market share, and most of the agents excluding B were found to display resistance case of Lincosimides such as Lincomycine and Clindmycin, resistant bacteria were found, with the except of agent B. Amoxicillin, Ampicillin and Penillin (type-Penecillins) and Erythromycin (type-Macrolide) were shown to contain resistant bacteria, with the except of agents Band E; the same for Norploxacin (type-Quinoline) and Neomycin antibiotics. Aminoglycosides such as Gentamycin and Streptomycin contained resistant bacteria, excluding agent B. Oxytetracyclin (type-Tetracycline), which is banned for use as resistant bacteria showed the highest sensitivity among the 12 antibiotics, revealed positive results in the test for resistant bacteria; again excluding of agents Band E. These results reveal that many agents contained resistant bacteria despite the fact that they were prohibited; this calls for a more accurate display of the facts and specifications, systematic distributions and strict verification processes of environment improving agents.

• Journal of Environmental Health Sciences
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• v.32 no.3
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• pp.227-234
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• 2006

There has been increasing concern in recent years about the occurrence, fate and toxicity of pharmaceutical products in aquatic environment. Although these compounds have been detected in a wide variety of environmental samples including sewage effluent, surface waters, ground water and drinking water, their concentrations generally range from the low ppt to ppb levels. It is therefore often thought to be unlikely that pharmaceuticals will have a detrimental effect on the environment. This study was conducted to determine the endocrine disruption effects of the several pharmaceutical residues in water using adult Japanese medaka (Oryzias latipes). The common antibiotics were used sulfa durgs (sulfamethoxazole and sulfamethazine) and tetracycline drugs (oxytetracycline and tetracycline). Positive control that was induced Vtg (vitellogenin) in male fish was used $17\beta$-estradiol. Vtg was qualified and quantified through Western blotting and ELISA. After SDS gel electrophoresis, the dominant protein band was identified to molecular weight approximately 205 kDa in whole body samples of vitellogenic female. In female medaka exposed to $17\beta$estradiol, there was no significant difference in total protein induction. In contrast, three to five day exposure of male fish to $17\beta$-estradiol resulted in more than 60.0% increase of total protein compared to that of control males (p<0.01). In case of antibiotics, female fish didn't show significant difference, but male fish was showed significant difference. In addition, Vtg induction in male fish was observed with all the test chemicals. On concentrations greater than 0.1 ppm of sulfamethoxazole, 1 ppm of sulfamethazine, 1 ppm of oxytetracycline and 20 ppm of tetracycline, Vtg induction was increased in a dose response manner. This study is one of the early reports suggesting potential endocrine disruption mechanism of antibiotic pharmaceutical products in aquatic ecosystem. Although the effect concentrations obtained from this study were high as unrealistically as in environments, it is endocrine disruption that we should be considered as one of the important consequences of pharmaceutical contamination at water environment, and warrants due attention in future researches.

• The korean journal of orthodontics
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• v.19 no.2
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• pp.57-73
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• 1989

The purpose of this study was to investigate the tissue response of the rat molar periodontium incident to intermittent orthodontic force. The author intended to observe the healing process of injured periodontium and the response of injured tissue to the resumed force. Oxytetracyclin 50mg/Kg was given to each rat intraperitonially. 5 days later, maxillary 1st molars were moved mesially from the incisors with closed coil spring of 100gram. 7 days later, the appliances were removed and 20mg/Kg of calcein were given intraperitonially to each rat. At the same time, maxillary left 1st molars of 15 rats were moved by the same method, but force was lowered to 20 gram. After 1 day, maxillary left 1st molars of another 15 rats were moved by the same method and 50mg/Kg of oxytetracycline was given intraperitonially. After 4 days, another 15 rats were treated as above. After 7 days, another 15 rats were treated as above. 1,4,7,10 and 14 days after change of force, 3 rats were sacrificed in each group respectively. 2 rats were decalcified, embedded in paraffin, and stained with hematoxylin-eosin stain and with Masson's trichrome stain. Another rat was embedded in polyester resin and undecalcified specimen were made. Microradiograms were taken with the undecalcified sections. Observations were made with light and fluorescence microscope. Following conclusions were made. 1. Connective tissue cells and vessels were infiltrated into the hyalinized tissue from the bony cleft and along the border of the hyalinized tissue with bone and root surface. At the same time, elimination of hyalinized tissue, bone and root resorption occurred. 2. Bone and root were resorbed directly and indirectly. 3. Hyalinized tissue was removed within 5 days after force removal. 4. Hyalinized zone was less extensive and easily removed as the rest period prolonged. 5. Hyalinized tissue developed more rapidly and extensively and lasted over 10 days as the force resumed on the already formed hyalinized tissue.

• Korean Journal of Veterinary Service
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• v.30 no.2
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• pp.219-231
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• 2007

The effects of intraduodenal administration of Clostridium perfringens type D whole culture in goats were evaluated to develop a reliable experimental model of enterotoxemia in this species and the eventual evaluation of treatment with different drug preparations was also carried out. A total of 28 conventionally reared healthy unvaccinated black bangle goat kids of 6-12 months of age were dosed intraduodenally with whole cultures of C peliringens type D. Four kids were used as controls and received sterile, nontoxic culture medium intraduodenally. All animals received starch solution into the abomasum. The clinical signs developed within 12 hours of post inoculation that were similar to those observed in naturally occurring cases. Among the clinical signs, diarrhea was most common (96.43%) followed by dyspnea (53.57%) and central nervous system (CNS) signs (25.0%). The most striking postmortem findings consisted of necrotizing pseudomembranous colitis (100.0%), lung edema (69.23%) and fluid filled intestines (61.53%). The protocol thus provided a reasonable model of naturally occurring enterotoxemia in goats, producing a range of clinical signs and postmortem changes similar to those observed in the natural disease. Beside this, treatment trial with different drug preparations showed penicillin combined with antitoxin was most effective (100.0%), followed by combination of oxytetracyclin with antitoxin, and combined preparation of antitoxin and sulfur drugs both showed 75% recovery rate. On the other hand, treatment with antitoxin, penicillin and oxytetracycline singly could protect goat enterotoxaemia only 25.0%, 50.0% and 50.0%, respectively. Thus in the present study, it eas observed that antisera in combination of antibiotics gave better recovery rate than the antitoxin or antibiotics alone.

• Korean journal of applied entomology
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• v.15 no.3 s.28
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• pp.107-110
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• 1976

A Witches'-broom disease of jujube (Zizyphus jujuba) with which mycoplasma-like bodies are associated is wide spread in South Korea. Jujube trees with witches'-broom symptoms were selected from 15-20 year old planting and treated with solution of oxytetracycline hydrochloride (Terramycin). Treatments were 1) one injection on April; 2) one postharvest injection on October; 3) two injections (April and July); 4) three injections (April, June and August) and 5) an untreated control. Each injection consisted of 500ml of 1,000 p.p.m. solution of oxytetracycline HCl transfused into affected trees from plastic reservoir through plastic tubes connected to 3 small holes drilled in the basal part of the tree trunks. Complete remission of witches'-broom symptoms was accomplished within one growing season by one spring (April) injection. One postharvest (Oct.) injection also prevented the symptoms in the following growing season. Two and three injection treatments prevented the symptoms for at least two growing seasons and restored previously severely diseased trees to normal or near normal conditions. Remission of symptoms was found only above the injection site while current season witches'-brooms developed from areas below the injection site and from untreated main scaffolds. The results of this experiment demonstrates that transfusion treatment with oxytetracyclin HCl is feasible for the practical control of witches'-broom of jujube.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.41-46
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• 2016

Bacterial fruit blotch (BFB) caused by Acidovorax avenae subsp. citrulli is defective disease to watermelon cultivated areas. To control of BFB, we investigated control efficiency to use commercial antibacterial pesticides. Growth inhibition zone on medium were formed as oxolinic acid WP and oxytetracycline WP. Control efficacy of four anti-bacterial pesticides on seed and seedling stage were performed. As a results, oxytetracyclin WP is shown over 90% control efficiency on seed and acibenzolar-S-methyl + mancozeb WP shown over 90% control efficiency on seedling stage Hot-water treatment method could be possible to reduced infection rate on seed. The conditions of hot-water treatments are $50{\sim}55^{\circ}C$ on 20~30 minutes. These results suggested that the methods were helpful watermelon seedling nursery to control of the bacterial fruit blotch by A. avenae subsp. citrulli.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.239-244
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• 1989

This work was for the elucidation of heterogeneity in a natural population of Rhizobium japonicum existing in Seoul National University's Experiment Field and of sensitivities of R. japonicum isolates for several antibiotics by using a method based on intrinsic antibiotic resistance (IAR). In addition, the suitability of IAR method for the recognition of R. japonicum strain was elucidated. Twenty seven isolates from various soybean cultivars cultivated at SNU's Experiment Field were tested to 4 antibiotics (streptomycin sulphate, kanamycin sulphate, ampicillin, oxytetracycline);There were 21 different IAR patterns among 27 isolates. It demonstrated diverse distribution of R. japonicum strains in SNU's Experiment Field. Their growth was inhibited at from a low concentration of about $1{\mu}g/ml$ to a high concentration of $400{\mu}g/ml$ for streptomycin sulphate, ampicillin, and oxytetracyclin. For kanamycin sulphate, on the contrary, all 27 isolates showed their growth inhibitances at below the concentration of $12.5{\mu}g/ml$. Two isolates identified as different strains from each other by the previous seroimmunological tests showed the same sensitivities for 4 antibiotics, and it seemed that IAR method was not perfect for the exact recognition of R. japonicum strain.