• Journal of Microbiology and Biotechnology
• /
• v.10 no.4
• /
• pp.514-517
• /
• 2000

Abstracts Six shikonin metabolites were obtained from human intestinal bacteria, Bacteriodes fragilis subsp. thetaotus. following biotransformation. The transformation of shikonin (1) was performed anaerobically for 3 day at $37^{\circ}C$ in thc bacterial suspension of B. Fagilis which was cultured overnight in GAM broth. The incubation mixture \vas extracted with EtGAc Lo give a dark-brown residue. The residue was apphed to a silica gel column, which was eluted successively with hexane (Fr. A), $CHCl_3$ (Fr. B), and $CHCl_3$:MeOH (9:I) (Fr. C). Six metabolites. Fr.A (2 and 3), Fr. B (6 and 7), and Fr. C (4 and 5) were isolated by repeated silica gel column chromatography, preparatlVe TLC, followed by Sephadex LH-20. In vitro cytotoxicities were tested against human tumor cell lines; PC-3 (prostate), ACHN (renal), A549 (lung), SW620 (colon), KS62 (leukemia), and Du145 (prostate). The shikonin metabolites 2. 4, 5, and 6 showed weaker cytotoxicity than the parenL shikonin (1). whereas shikonin monomenc metabolite 3 ($ED_{50}{\;}O.44-{\;}1.22{\;}\mu\textrm{g}/ml$) and dimeric metabolite 7 ($ED_{50}{\;}O.48-{\;}2.35{\;}\mu\textrm{g}/ml$) exhibited stronger activities compared with adriamycin, which was used as the positive control.ontrol.

• Korean Journal of Animal Reproduction
• /
• v.13 no.2
• /
• pp.105-112
• /
• 1989

These experiments were carried out to obtain the basic information for in vitro fertilization and development of bovine follicular oocytes matured in vitro. The bovine ovaries were obtained at a slaughter house and the follicular oocytes surrounded by cumulus cells were collected by puncturing follicles with 2-6mm of diameter. Bovine oocytes were matured in vitro for 24-26 hours in a CO2 incubator with 5% CO2 in air at 39$^{\circ}C$. The medium used for maturation was TCM199 supplemented with hormones, pyruvate, FBS and antibiotics. Epididymal spermatozoa were capacitated by in vitro culture for 2-3 hours in BO solution containing bovine serum albumin(5mg/ml) and caffein(2.5mM). Insemination was made by introducing about 10-15 matured oocytes into the suspension of capacitated spermatozoa. Six hour after inseminatin the eggs were transferred to TCM 199 supplemented with FBS(10%) for in vitro development. The results obtained in these experiments were summarized as follows : 1. The maturation rate of oocytes following incubation for 24-26 hours was 78.4%(228/291). 2. Of total 250 oocytes, 172 embryos extruded 2nd polar body following in vitro culture with spermatozoa for 20 hours, and the rates of embryos developed to 2-, 4-, 8-, 16-cells and morula or early blastocyst were 64.0, 39.2, 22.0, 15.2 and 11.2%, respectively. 3. The time needed for development to 2-, 4-. 8-, 16-cell stage and morula was 42.5$\pm$5.4, 58.0$\pm$9.2, 74.4$\pm$11.5, 96.1$\pm$13.4 and 119.0$\pm$18.2 hours, respectively.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.9
• /
• pp.1401-1409
• /
• 2015

The aim of this study was to develop a SYBR Green-based real-time PCR assay for the rapid, specific, and sensitive detection of Acidovorax avenae subsp. citrulli, which causes bacterial fruit blotch (BFB), a serious disease of cucurbit plants. The molecular and serological methods currently available for the detection of this pathogen are insufficiently sensitive and specific. Thus, a novel SYBR Green-based real-time PCR assay targeting the YD-repeat protein gene of A. avenae subsp. citrulli was developed. The specificity of the primer set was evaluated using DNA purified from 6 isolates of A. avenae subsp. citrulli, 7 other Acidovorax species, and 22 of non-targeted strains, including pathogens and non-pathogens. The AC158F/R primer set amplified a single band of the expected size from genomic DNA obtained from the A. avenae subsp. citrulli strains but not from the genomic DNA of other Acidovorax species, including that of other bacterial genera. Using this assay, it was possible to detect at least one genomeequivalents of the cloned amplified target DNA using 5 × 10⁰ fg/µl of purified genomic DNA per reaction or using a calibrated cell suspension, with 6.5 colony-forming units per reaction being employed. In addition, this assay is a highly sensitive and reliable method for identifying and quantifying the target pathogen in infected samples that does not require DNA extraction. Therefore, we suggest that this approach is suitable for the rapid and efficient diagnosis of A. avenae subsp. citrulli contaminations of seed lots and plants.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.21 no.2
• /
• pp.97-104
• /
• 1988

Condensed phosphates have been used in various meat products to enhance the water holding capacity, to improve texture and to prevent the development of off flavors and off odors. This study was intended to observe the effects of poly - and pyrophosphate on the growth of sanitary indicative bacteria and food poisoning bacteria. The bacteriostatic effect of poly - and pyrophosphates against Gram positive bacteria was much stronger than that of against Gram negative organisms. The effective inhibitory concentration of sodium polyphosphate on the growth of bacteria was varied by species such as $0.3\%$ to Staphylococcus aureus, $0.9\%$ to Salmonella, and more than $1.0\%$ to Escherichia coli in nutrient broth. When Staphylococcus aureus suspension was treated with $0.5\%$ sodium polyphosphate at $35^{\circ}C$ for 1 hour, the release of UV-absorbing substances from the organism was confirmed. However no significant effect was observed in Escherichia coli under the similar condition. When alaska pollack fillets were dipped in $ 3.5\%$ sodium polyphospahate at $2^{\circ}C$ for 1 min. prior to freezing, the viable cell count and coliform MPN's of the frozen product were decreased with the range of 30 to $50\%$ in comparison with those of control.

• Microbiology and Biotechnology Letters
• /
• v.36 no.2
• /
• pp.115-120
• /
• 2008

Bacterial populations from the rhizosphere were obtained and the efficacy of the bacterial wilt suppression, root colonizing ability and resistance to three kinds of chemical pesticides were assayed. According to these results, SKU48-2 was selected as a potential biological agent to control the bacterial wilt caused by Ralstonia solanacearum. SKU48-2 strain at $10^8CFU/ml$ inoculum was able to suppress the bacterial wilt up to 60% in greenhouse trials. Also, the resistance of SKU48-2 to chemical pesticides make possible to use in combination with chemical pesticides for the control of bacterial wilt. Three different powder formulations of SKU48-2 were developed. The shelf-life of powder formulations was effective up to 6 months of storage. Unformulated bacterial suspension could not be stored for 2 weeks, at which time cell viability was completely lost. According to 16S rDNA sequence data, the SKU48-2 stain was identified as Bacillus subtilis.

• Korean Journal of Veterinary Research
• /
• v.26 no.1
• /
• pp.117-124
• /
• 1986

The present study was undertaken to evaluate rosette formation and NK activity of splenic lymphocytes in 3-methylcholanthrene (MCA) treated mice. Mice were sensitized iv with 0.1ml of 1% sheep red blood cell (SRBC) suspension were treated with a single ip injection of olive oil alone or with different doses of MCA in oil at various time before or after sensitization, and were challenged at 4 days after SRBC. Rosette formation and NK activity of splenic lymphocytes were measured at 24 hours after challenge. Erythrocyte(E) rosette formation of splenic lymphocytes was significantly depressed in mouse treated with large dose of MCA (5~50mg) regardless of injecting time. But, there was no difference in the response between the treated with small dose of MCA (0.5mg). Whereas erythrocyte-antibody(EA) rosette or erythrocyte-antibody-complement(EAC) rosette forming cells were significantly depressed by MCA. Under small dose of MCA (0.5mg), any difference of NK activity was not observed in all course of injecting time. But, under large dose of MCA, the activity was markedly inhibited to about half the values seen in control and this suppression was transient, resulting that the normal level was reached again 19 days after MCA. These results, which conform with the predictions of immunosuppression hypothesis, suggest that MCA inhibits immunological responses including NK activity and thereby allows the outgrowth of antigenic neoplastic cells.

• Korean Journal of Veterinary Research
• /
• v.38 no.2
• /
• pp.359-365
• /
• 1998

This study was conducted to isolate the protozoan parasite Babesia gibsoni by intraerythrocytic culture method of micoraerophilous stationary phase(MASP) and evaluate the possibility of application for the detection of B gibsoni in canine babesiosis. Also, indirect fluorescent antibody test(IFAT) and thick blood smear(giemsa stain), direct light microscopy (DLM), as control diagnostic tests, were conducted to compare diagnostic effects between MASP, IFAT and DLM. The results obtained from this study were summarized as follows. The protozoan parasite B gibsoni multiplied in 24-well polystyrene plate containing 1.2ml of canine red blood cell suspension in RPMI 1640 medium(pH 7.0) which is contained 20~40% normal canine serum(NCS) under the MASP condition of 5% $CO_2$ and 95% air at $37^{\circ}C$ incubator. Under the above MASP culturing system the percentage of parasitized erythrocytes(PPE) after incubation for 9 days reached the peak. The levels of PPE in MASP culture were shown more higher by exchanging the medium at 24 hour intervals. The parasite were purely isolated from MASP culture of canine red blood cells collected from dogs(pit bullterrier) infected with B gibsoni naturally. Among the total of 83 heads of pit bullterrier blood samples the positive rate was 32 heads(38.5%) in DLM, 45 heads(54.2%) in IFAT and 42 heads(50.6) in MASP culture. In negative cases of IFAT and DLM the isolation rates of B gibsoni by MASP culture were 16 heads(42.1%) of 38 heads and 16 heads(28.6%)% of 56 heads, respectively. From this study it was suggested that MASP culture method by RPMI 1640 medium was a reliable and useful diagnostic test for the diagnosis of B gibsoni infections in canine babesiosis.

• Journal of Environmental Health Sciences
• /
• v.39 no.4
• /
• pp.376-382
• /
• 2013

Objectives: The objectives of this study were to identify the virucidal efficacy against the viral hemorrhagic septicemia virus (VHSV) of an aquatic disinfectant tablet composed of calcium hypochlorite. Methods: Virucidal efficacy was determined through the viability of VHSV contacted with the disinfectant in a viral stock cultured in a fathead minnow cell line. An aquatic disinfectant tablet and VHSV were reacted under distilled water (DW), hard water (HW) or organic matter suspension (OM) conditions. Results: Under DW and HW conditions, VHSV was inactivated with 24,000- and 2000-fold dilutions of the aquatic disinfectant tablet, respectively. With the investigation of the antiviral effect of the disinfectant under OM conditions, VHSV was inactivated with a 16,000-fold dilution of the aquatic disinfectant tablet. Conclusions: The results from this study showed that the aquatic disinfectant tablet was a highly effective disinfectant against VHSV. In the future, a controlled field trial is required to determine whether the use of an aquatic disinfectant tablet will be able to reduce VHSV in a cultured marine fish farm.

• Toxicological Research
• /
• v.23 no.4
• /
• pp.383-389
• /
• 2007

Recombinant human granulocyte-macrophage colony stimulating factor (hGM-CSF) regulates proliferation and differentiation of hematopoietic progenitor cells and modulates function of the mature hematopoietic cells. In the previous study, we reported that hGM-CSF could be produced in transgenic rice cell suspension culture, termed rhGM-CSF. In the present study we examined the single and repeated dose toxicity of rice cells-derived hGM-CSF in SD rats. During single dose toxicity study for 7 days, there were no any toxic effects at any dose of from 10 to $1000{\mu}g/kg$. The lethal dose ($LD_{50}$) was not found in this range. Moreover, repeated dose toxicity study of 14-days period and at the doses of 50 and $200{\mu}g/kg$ (i. v.) of rhGM-CSF did not show any changes in food and water intake. There were also no significant changes in both body and organ weights between the control and the test groups. The hematological and blood biochemical parameters were statistically not different in all the groups. These results suggest that rhGM-CSF has no toxicity in SD rats.

• Proceedings of the Korea Society of Environmental Toocicology Conference
• /
• 2003.10a
• /
• pp.174-174
• /
• 2003

There are many synthetic chemicals, such as di(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP), used in chemical reaction processes in industry. The establishment of toxicity and detection of synthetic chemicals that may pose a genetic hazard in our enviornment is subjects of great concern at present DEHP, a ubiquitous phthalate plasticizer, induces a wide range of developmental and reproductive toxicities in mammals. DEHP belongs to the large diverse class of peroxisome proliferator compounds, which include herbicides, hypolipidemic drugs. DBP is a plasticizer used to products containing nitrocellulose, polyvinyl acetate, and polyvinyl chloride such as food wraps and blood bags. DBP is also used in cosmetics as a solvent and fixative for perfumes, a suspension agent for solids, an antifoamer, a skin emollient, and hair spray The present study was performed to examine patterns of gene expression in MCF-7 cells following DEHP and DBP exposure. Changes in gene expression were determined by microarray analysis using KISTCHIP-400 including 401 endocrine related genes based on public database and research papers. Of the genes analysis, we determined that genes detected by array showed a 2-fold or greater change in their expression level(increase or decrease). The results of this study demonstrate that a number of genes were differentially expressed in MCF-7 cells but these changes were not significant. Therefore, we keep going this study using microarray analysis and future studies will examine changes of gene expression on time-course and does treatment in variable cell lines.