• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.66-73
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• 1993

Psychrotrophic bacterial strains utilizing crude oil as their sole carbon and energy sources were isolated from Antarctic soil and sea sediments. One of the strains named AI-I showed the hightest activity for emulsification of crude oil and the best growth. This strain was identified as Acinetobacter calcoaceticus. A. calcoaceticus AI-I strain contains a plasmid (OCT plasmid) which was related to the utilization of alkane compounds. The molecular weight of this plasmid was estimated to be about 110 Md by agarose gel electrophoresis. The cured strain of A. calcoaceticus AI-I strain (OCT ) was not able to utilize normal hydrocarbon compounds ($C_6C_{17}$) as carbon and energy sources. A. ca/coaceticus AI-1 was resistant to ampicillin and sensitive to streptomycin, kanamycin, chloramphenicol, tetracycline. The results suggested that this strain carries a plasmid (OCT) responsible for oil utilization which is quite stable and might be concerned with antibiotics resistancy.

• The Korean Journal of Zoology
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• v.26 no.1
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• pp.19-28
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• 1983

Alkaline elution profiles showed that the frequency of DNA single strand breaks associated with DNA-protein crosslinks in cells treated with both an inducing dose of MMC $(MMC_1)$ and a challenge dose of MMC $(MMC_2)$ was slightly less than that in cells treated with MMC alone. The amount of unscheduled DNA synthesisi in cells treated with both $MMC_1$ and $MMC_2$ was greater than that in cells treated with MMC alone. This enhancement of exicision repair detected by UDS autoradiography and alkaline elution, was not observed, when cells were incubated with cyclohexmide between the two treatments of $MMC_1$ and $MMC_2$. These results suggest that MMC-damaged DNA from Chinses hamster cells is repaired by excision repair mechanisms that require de novo protein synthesis for enhancement, and that an inducible repair mechanism may exist in CHO cells.

• Korean Journal of Microbiology
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• v.25 no.1
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• pp.9-16
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• 1987

Three strains of bacteria utilizing salicylate, KU801(pKU5, pKU8), KU803(pKU6, pKU9), and KU806(pKU7, pKU10), were selected from the isolates and identified as Pseudomonas putida. By agarose gel electrophoresis, it was found that the strains had two plasmids each. All three strains were resistant to antibiotics such as ampicillin, tetracyclin, and chloramphenicol, and did not utilize other aromatic and aliphatic hydrocarbons examined except salicylate. The plasmids (pKU5, pKU6, and pKU7) of larger molecular weight were cured by treatment with mitomycin C and frequencies of curing were 0.4%, 1.67%, and 0.75%, respectively. Cured strains did not degrade salicylate and still had antibiotic resistances, which were identical with wild strains. The genes for salicylate degradation were proved to be enclded on thier plasmids. The molecular weights of pKU5 and pKU6 were estimated as 103.5Md, and that of pKU 7 as 101 Md. The new SAL plasmids, pKU5, pKU6, and pKU7 were transferred to P. putida and P. aeruginosa, but not to E. coli.

• Environmental Analysis Health and Toxicology
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• v.22 no.3
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• pp.263-269
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• 2007

Chitosan is a depolymerized and partially deacetylated derivative of chitin. We investigated the cytotoxicity of chitosan in cancer cell lines, such as P388, L1210, HCT-15, SK-HepG-1 and mouse splenocytes as a normal cell by MTT assay. To clarify whether chitosan enhances cytotoxicity of anticancer drugs, we also examined the cytotoxicity of combined treatment with chitosan and anticancer drugs, such as cisplatin, mitomycin C, and 5-fluorouracil in cancer cell lines in vitro. Chitosan ($37.5\;{\mu}g/mL,\;75\;{\mu}g/mL,\;112.5\;{\mu}g/mL,\;and\;150\;{\mu}g/mL$) showed concentration-dependent cytotoxicity in the cancer cell lines. In addition, chitosan showed relatively lower cytotoxicity in normal cells than in the cancer cell lines. Particularly, this trend was significant at high doses of chitosan, i.e. $112.5\;{\mu}g/mL,\;and\;150\;{\mu}g/mL$. Thus, these results suggest that chitosan may selectively induce the growth inhibition in cancer cell lines, compared to normal cells. Furthermore. the co-treatment of chitosan and anticancer drugs exhibited an apparant synergistic cytotoxicity in murine lymphoma cell lines, i.e. P388 and L1210 at $37.5\;{\mu}g/mL$ of chitosan rather than at $75\;{\mu}g/mL$ of chitosan, but such phenomenon could not be observed in solid tumor cell lines, i.e. HCT-15 and SK-HepG-1. However, chitosan did'nt reduced the cytotoxicity against normal mouse splenocytes induced by anticancer drugs. Therefore, it is concluded that the combination of chitosan and anticancer drugs might be useful for the cancer chemotherapy.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.2
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• pp.115-121
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• 2009

Functional defects in mitochondria are involved in the induction of cell death in cancer cells. We assessed the toxic effect of camptothecin against the human cervical and uterine tumor cell line SiHa with respect to the mitochondria-mediated cell death process, and examined the combined effect of camptothecin and anticancer drugs. Camptothecin caused apoptosis in SiHa cells by inducing mitochondrial membrane permeability changes that lead to the loss of mitochondrial membrane potential, decreased Bcl-2 levels, cytochrome c release, caspase-3 activation, formation of reactive oxygen species and depletion of GSH. Combination of camptothecin with other anticancer drugs (carboplatin, paclitaxel, doxorubicin and mitomycin c) or signaling inhibitors (farnesyltransferase inhibitor and ERK inhibitor) did not enhance the camptothecin-induced cell death and caspase-3 activation. These results suggest that camptothecin may cause cell death in SiHa cells by inducing changes in mitochondrial membrane permeability, which leads to cytochrome c release and activation of caspase-3. This effect is also associated with increased formation of reactive oxygen species and depletion of GSH. Combination with other anticancer drugs (or signaling inhibitors) does not appear to increase the anti-tumor effect of camptothecin against SiHa cells, but rather may reduce it. Combination of camptothecin with other anticancer drugs does not seem to provide a benefit in the treatment of cervical and uterine cancer compared with camptothecin monotherapy.

• Korean Journal of Medicinal Crop Science
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• v.20 no.1
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• pp.16-19
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• 2012

The desmutagenic activity of the water extract of Areca catechu L. on the mutagenicity induced by aflatoxin $B_1$ ($AFB_1$), N-methyl-N-nitro-N'-nitrosoguani-dine (MNNG), mitomycin C (MMC) and 4-nitroquinoline 1-oxide (4-NQO) was studied by using the SOS Chromotest with Escherichia coli PQ37. The inhibition rates of water extract of Areca catechu L. at concentration of $100{\mu}g/assay$ were 41.0%, 47%, 46%, and 32% against $AFB_1$, MNNG, MMC and 4-NQO, respectively. The water extract of Areca catechu L. was separated into methanol soluble and methanol insoluble parts. The methanol insoluble part exhibited higher inhibition effect than the methanol soluble part against the mutagenic activities of MNNG. Step-wise fractionation of methanol insoluble part was done to obtain methanol, ethyl acetate and water fractions. Among these fractions, water fraction had the strongest inhibitory effect of 45.0% against mutagenicities of MNNG. The inhibition rates of aqueous fraction of methanol-insoluble from water extracted Areca catechu L. at concentrations of 1.61, 16.13, 161.29 and $322.58{\mu}g/mL$ were 12.0%, 24.0%, 47.5% and 62.0%, respectively. The water fraction showed the inhibitory effects with dose response against the mutagenic activity induced by MNNG.

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.701-710
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• 1993

The pine needles, Pinus densiflow Sieb. et Zucc., which is a feed for goats showing a low incidence rate of cancer were evaluated to confirm the potent anticancer effects, with or without several conventional anticancer drugs. The pine needles collected from Mt. Buk-Han located near Seoul were extracted with 95% methanol and methand and concentrated. From the methanol extract, SOM-A, was extracted dichlormethane and SOM-B was extracted with ethyl acetate. SOM-C was extracted with distilled water. These extracts were tested for their antitumor activities in vitro and in vivo. Among them, SOM-A and SOM-C exhibited potent antitumor activities described as belows. 1. The cytotoxic effects of SOM-A and SOM-C were examined against in vitro cultured murine and humman tumor cells. SOM-A showed strong cytotoxicity against human tumor cell lines and SOM-C showed strong cytotoxicity against murine tumor cell lines tested. 2. The antitumor effects of SOM-A and SOM-C were examined against P388 and L1210 of mouse ascitic tumors. The highest mean survival time(MST) ration was 151%(P388) for SOM-C(90mg/kg). 3. To compare the antitumor effects of SOM-A, SOM-B, and SOM-C against solid tumors, S-180 and Ehrlich carcinoma were implanted subcutaneously to mice on Day O. The drugs were given intraperitoneally to mice once a day on Days 1-20, and the tumor weights were measured on Day 21. SOM-A showed inhibition of tumor growth more than 50% in the experiment on S-180 and Ehrlich, and SOM-C also markedly inhibited tumor growth. However, SOM-B had no effect. 4. SOM-C combined with ${\alpha}$-interferon and SOM-C combined with Mitomycin-C enhanced the antitumor activities against murine ascitic tumors P388 leukemia.

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.282-289
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• 1987

The characteristics of the plasmid pKU10 isolated from Pseudomonas putida KU816 were investigated and its restriction map was constructed. The pKU10 plasmid was a small R plasmid carrying genes for resistance to ampicillin, tetracyclin, and chloramphenicol, and cured by treatment with mitomycin C. The molecular size of pKU10 was estimated to be 9.4Kb. Pseudomonas strains and E. coli cells could be transformed for antibiotic resistance characters specified by pKU10 plasmid DNA. By incompatibility test with other plasmids, pKU10 is grouped into IncP-1. EcoRI, XhoI, SalI, BglII, and SmaI cleaved pKU10 once, while PstI cleaved at two sites, and HindIII cleaved at six sites. The restriction map was constructed by partial and complete digestion of the purified plasmid DNA with single, double, or triple restriction enzymes. Thus, pKU10 is expected to be used for a cloning vector in Pseudomonas cells.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.7-13
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• 1999

The stimulatory effect of recombinant human basic fibroblast growth factor (bFGF) on wound healing was evaluated in healing-impaired animal models. Full-thickness wounds were made in prednisolone-treated mice, streptozotocin (STZ)-induced diabetic rats and mitomycin C (MMC)-treated rats. Saline or bFGF at a dose of 1, 5, or $25\mu\textrm{g}$ per wound was applied to the open wound once a day for three to five days. The degree of wound healing was assessed using wound size and histological parameters such as degree of epidermal and dermal regeneration. Local application of bFGF accelerated wound closure significantly in a dose-dependent manner in all healing-impaired wounds (p<0.05). The wound healing effect of bFGF was further confirmed by histological examination in MMC-treated rats. Epidermal and dermal regeneration were enhanced in bFGF-treated wounds with a dose-related response. Dermal regeneration parameters such as collagen matrix formation and angiogenesis were significantly increased in $5\mu\textrm{g}$, or $\25mu\textrm{g}$ of bFGF-treated wounds when compared to saline-treated wounds (p<0.05). pectin immunostaining on day 8 for vascular endothelium showed an increased number of neovessels in bFGF-treated wounds. These results suggest that topical application of bFGF has beneficial effects on wound healing by angiogenesis and granulation tissue formation in healing-impaired wounds.

• Korean Journal of Microbiology
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• v.17 no.3
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• pp.97-130
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• 1979

Many industrial processes those employ bacteria are subjected to phage infestations. In L-glutamic acid fermentions using acetic acid, the phage infestations of the organisms have been recently recognized. In efforts to elucidate the sources of phage contamination involved in the abnormal fermentation, a series of study was conducted to isolate the phages both from the contents of abnormally fermented tanks and the soil or sewage samples from the surroundings of a fermentation factory, to define major charateristics of the phage isolates, and finally to determine the correlation between the phage isolates and temperate phages originating from the miscellaneous bacterial species isolated from the soil or sewage samples. The results are summarized as follows; 1) All phages were isolated from the irregular fermentation tanks and soil or sewage samples, and they were designated as phage PR-1, PR-2, PR-3, PR-4, PR-5, PR-6, and PR-7, in the order of isolation. These PR-series phages were proved to be highly specific for the variant strains of Br. lactofermentum only, namely, phage PR-1 and PR-2 for Br. lactofermentum No. 468-5 and phage PR-3~PR-7 for Br. lactofemrentum No. 2256. By cross-neutralization test, the 7 phagescould be subdivided into 3 groups, i. e., phage PR-I and PR-2 the first, phage PR-3, PR-4, PR-5, PR-6 the second, and the phage PR-7 the third. 2) The 7 phages were virulent under the experimental conditions. They produced plaques with clear and relatively sharp margins without distinct halo. The mean sizes of plaques were 1.5mm in diameter for phage PR-1 and PR-2, and 1. Omm for phages PR-3~PR-7. Double layer technique modified by Hongo and described by Adams, was applied to assay of the PR-series phages. The factors influencing the plaques were as follows;young age cells of host bacteria cultured for 3-6 hours represented the largest number and size, optimum was pH 7.0, incubation temperature was $30^{\circ}C$, and agar concentration and amount of overlayer medium were 0.6% and 0.2ml, respectively. 3) PR-series phages were stable in 0.05M tris buffer and 0.1M ammonium acetate buffer solution. The addition of $5{\times}10^{-3}M$ magnesium ion effectively increased the stability. Thermostability experiments indicated that PR-series phages were stable at the teinperture between $50^{\circ}{\sim}55^{\circ}C$ in nutrient medium, $45^{\circ}{\sim}50^{\circ}C$ in buffer solution. However, the phages mere completely inactivated at 603C and 65$^{\circ}$C within 10 minutes. The phages were stable at the range of pH6~9 in nutrient medium and of pH 8-9 in buffer solution, respectively. Exposure of the phages to UV for 25, 60 and 100 seconds resulted in the complete loss of infectivily, respectively. 4) Electron microscopy showed that PR-series phage particles exhibited rather similar morphology, differing in the size All of PR-series phages had a multilateral head and had a simple long tiil about three to five times long as compared with head. By the size, phage PR-1 and PR-2, PR-3, PR-4, PR-5, and PR-6 and PR-7 were classified into same groups, respectively. The head and tail size of phage PR-1, PR-5, PR-5(T) and PR-7 were 85nm, 74nm and 235nm and 350mm, and 72nm and 210nm, respectively. 5) Nucleic acids of PR-series phages were double stranded DNA. The G+C contents of phage PR-1, PR-5 and PR-7 were 56.1, 52.9 and 53.7, respectively. The values of G+C contents derived from the $T_m$ were in agreement with the chemically determined values. 6) PR-series phages effectively adsorbed on their host bacteria at the rate of more than 90% during 5 min. K value for phage PR-1, PR-5 and PR-7 were calculated to be $6{\times}10^9 ml$ per minute, respectiveky. The pH of the medium did effect adsorption rate, but both temperature and age of host cells did not. Generally, optimum adsorption condition of phages seemed to be almost same as optimum growth conditions of host bacteria. 7) In one-step growth experiments, the latent periods at $30^{\circ}C$ for PR-1, and PR-7 were about 70, 50 and 55 min, respectively. The corresponding average burst size was 200, 70 and 90, respectively. Lpsis period according to the multiplicity of infection and a phage series. In case of m. o. i. 100, strain No. 2256 (PR-5) and No. 468-5(PR-1) failed to grow and turbidity decreased after 50 and 70min, respectively. 8) In the lysate of a plaque purified phage PR-5 infected bacteria, there observed 2 types ofphage particles, i. e., phage PR-5 and PR-5 (T) of similar morphology but differing at the length of phage tail, and phage tail like particles. The phage taillike particles could be divided into 4 types by the length. Induction experiments of Br. lactofermentum with UV irradiation, mitomycin C or bacitracin treatment produced neither phage PR-5 (T) or phage tail-like particles. 9) No lysis occured when the growth of 7 strains of miscellaneous bacteria, isolated from soil and sewage samples, were inoculated with either phage PR-5 (T) or phage tail-like particles the inoculation of phage PR-5 pellet resulted in the growth inhibition of the orgainsms in the spot test. The lysates obtained from 3 miscellaneous soil derived bacteria following mitomycin C treatment the growth of Br. lactofermentum, but did not lyze the bacterium.