• Applied Biological Chemistry
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• 제19권4호
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• pp.189-201
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• 1976

In an effort to develop a microbial in secticide, B. thdringiensis var. thuringiensis was cultured in the medium composed of cocoon-cooked water from a filature. The results obtained are summarized as followss : (1) Bacillus thuringiensis is a bacterium producing a ${\delta}-endotoxin$ especially toxic to lepidopterous insects and a thermostable exotoxin harmful to dipterous insects. (2) With a view to utilizing the cocoon-cooked water discarded from the filature, as a nutrient source in the B. thuingiensis culture, it was analyzed to contain large amounts of various minerals and protein (7.5 mg/ml) believed to be extracted from the pupae. (3) A large amount of the ${\delta}-endotoxin$ can be obtained most cheeply by using cocoon-cooked water instead of distilled water in preparing GYS and citrate salts media. (4) The largest amount of a mixture of the vegetative cells, spores, and crystals was obtained by addition of 8 gr/l of glucose to the GYS medium. (5) The growth of the bacterium was far better, when leucine, isoleucine, and valine were added all together to the citrate salts medium to the concentration of $1.25{\times}10^{-3}M$. (6) The best growth was observed by addition of Na-glutamate to the citrate salts medium to the concentration of $2.5{\times}10^{-3}M$. (7) The optimal culture time ranged from 9 to 15 days. (8) The highest mortality was shown in Pieris rapae Linne with a pH of the total body extract of 8.4, whereas Dendrolimus spectabilis Butler and Bombyx mori Linne with lower pH's were less susceptible to the ${\delta}-endotoxin$. (9) The presence of the thermo stable exotoxin was confirmed by the fact that the supernatant of the culture was very toxic to the Drosophila melanogaster tested.

• Clinical and Experimental Reproductive Medicine
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• 제25권2호
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• pp.207-216
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• 1998

Certain types of somatic cells, as well as follicular cumulus cells associating with mammalian oocytes, are known to produce beneficial effects on in vitro fertilization and pre implantation development of mammalian eggs when they are present in oocyte culture medium. To investigate the nature of the effects of somatic cells, the resistance of mouse oocytes against chymotrypsin treatment was examined after culture within various cell conditioned media. When mouse oocytes matured for 17-18 hr in the presence of cumulus cells were treated with 1 % chymotrypsin, half of them remained still alive even after 240 min $(t_{50}>240.0)$. In contrast half of mouse oocytes cultured without cumulus cells underwent degeneration within 65.0 min $(t_{50}=65.0{\pm}13.2min)$ of the same treatment. To see if the effects were duc to the secretory products of cumulus cells, mouse cumulus cells were cultured for 20 hr in medium containing 0.4% BSA and the supernatant of culture medium (conditioned medium) was taken. After maturation in the cumulus cell conditioned medium, mouse oocytes exhibited $t_{50}=190.0{\pm}10.8$ min upon chymotrypsin treatment whereas half of oocytes cultured without conditioned medium degenerated within 25.5 min. Human granulosa cell conditioned medium gave similar effects such that oocytes matured in conditioned medium exhibited $t_{50}=183.3{\pm}19.1$ min while $t_50$ of control group oocytes was $60.0{\pm}6.8$ min, Oocytes matured in vero cell conditioned medium exhibited $t_{50}=196.7{\pm}8.8$ min. On the other hand, amniotic cell conditioned medium resulted in the chymotrypsin resistance of $t_{50}=80.0{\pm}8.4$ min which was not statistically different from the control value of $t_{50}=48.0{\pm}13.2$ min. Based upon these results, it is suggested that certain somatic cell types including cumulus cells might change the biochemical properties of mouse oocyte membrane during meiotic maturation as revealed by the enhanced resistance against chymotrypsin treatment. Such effects of somatic cells appear to be mediated via the secretory products rather than direct communication between somatic cells and oocytes.

• Journal of Veterinary Clinics
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• 제27권4호
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• pp.311-314
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• 2010

Bartonella henselae is the causative agent of cat scratch disease. Although cats are the main zoonotic reservoirs of Bartonella spp., unusual cases of cat scratch disease caused by a domestic dog scratch have been recently reported. For the in vivo B. henselae infection, eight dogs were inoculated intradermally with $2{\times}10^8CFU$ of B. henselae Houston-1 suspended in 1 ml of phosphate buffered saline on day 0 and subsequent injections of the same amount given intradermally on days 21, 28, 36, 58 and 64. After in vivo canine B. henselae infection was confirmed by nested PCR, the IFN-$\gamma$ levels of the culture supernatant of PBMC stimulated with B. henselae was significantly higher in the B. henselae-PCR positive group than the B. henselae-PCR negative group. Our results showed that the canine immune responses against B. henselae were different from those of cats. Th1 activation by B. henselae stimulation was characterized in dog peripheral blood mononuclear cells, whereas Th2 activation was reported in B. henselae-infected cats.

• Korean Journal of Agricultural Science
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• 제4권1호
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• pp.105-111
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• 1977

Inhibitory effect of sugars on lipase production by Trichosporon cutaneum was observed in the previous study (Kim, 1972), and inhibition was distinctive by the addition of glucose, fructose, mannose, xylose and arabinose to the soybean meal medium among various carbon sources. These experiments were carried out to study the effect of sugars on cell growth and lipase production by the strain using the soybean extracts liquid medium under a shaking culture system. Changes in color and pH of the medium were caused by heat sterilization when various sugars were added. To elucidate the possible effect of these coloring matters on lipase production and cell growth: changes in pH of the culture, cell concentration and level of the enzyme activities were determined when the culture was grown for 48 hours at $30^{\circ}C$ on a reciprocal shaker. The results obtained were as follows: 1. Density of brownish color which formed during heat sterilization was varied with the variety of sugar used, ie, strong in pentose such as xylose: weak in hexose such as galactose, mannose, glucose: very weak in disaccharide such as maltose, sucrose. When the color density was stronger, decrease in pH after sterilization was marked. 2. Cell growth and lipase production was not so effect by the coloring matters as by sugars. 3. The more the cell mass of the culture, the lower the level of lipase production in the culture supernatant. 4. Among the sugars which caused the distinctive inhibition of lipase production, a slight relief of inhibition was noticed by the addition of xylose, whereas the cell growth was repressed. 5. When cell growth was better, decrease in pH of the medium was greater during cultivation.

• Korean Journal of Microbiology
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• 제46권2호
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• pp.127-133
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• 2010

The purpose of this work was to investigate the antibacterial activity derived from a lactic acid bacterium, Lactococcus lactis HK-9, isolated from the feces of a 2-day newborn infant. We characterized the physiological and biochemical properties of this strain. Both the BIOLOG system and phylogenetic analysis using 16S rRNA sequencing were utilized for identification, and the strain was assigned to the Lactococcus lactis species, designated as L. lactis HK-9, and registered in GenBank as [GU936712]. We monitored growth rate, production of lactic acid and acetic acid as metabolites, and pH during growth. The maximum concentrations of lactic acid and acetic acid reached 495.6 mM and 104.3 mM, respectively, and the initial pH of the cultures decreased from 7.0 to 4.1 after incubating for 60 h. HPLC was used to confirm the production of lactic acid and acetic acid. Significant antibacterial activity of the concentrated supernatant was demonstrated against Gram-positive (e.g., Staphylococcus aureus, Enterococcus faecalis, Listeria monocytogenes, MRSA) and Gram-negative (e.g., Escherichia coli, Salmonella enteritidis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Shigella sonnei) bacteria by the plate diffusion method. The antibacterial activity was sensitive to protease, and the molecular weight of the presumed bacteriocin molecule was estimated to be about 4 kDa by tricine-SDS-PAGE.

• The Korean Journal of Mycology
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• 제27권4호통권91호
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• pp.289-292
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• 1999

We investigated the isolation method of mushroom infesting pests, Lycoriella mali, Coboldia fuscipes, Histiostoma sp. from mushroom-growing compost. Sugar solution of different densities (0, 10, 20, 30, 40, 50%) was tested to provide a means of seperating mushroom pests from the compost media. Thus, 40% sugar solution was suitable for isolation. The sieve size to entrap the pests was $30{\sim}140$ mesh; Lycoriella mali was trappped mainly $30{\sim}65$ mesh sieve, Coboldia fuscipes was caught mainly $30{\sim}100$ mesh sieve, Histiostoma sp. was trapped mainly $65{\sim}140$ mesh sieve. An isolation procedure was as follows; The infested compost was disintegrated in water and poured onto a set of 16, 30, 80, 140-mesh sieve. The material caught in the sieve is added in 40% sugar solution and then most compost particle were massed at the bottom while the supernatant contains mushroom pests. The upperlayer material was poured into a Seperatory funnel and the sediment at the bottom is drained off. The remaining material are washed off examination dish for study.

• Korean Journal of Veterinary Research
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• 제38권1호
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• pp.29-42
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• 1998

$Mg^{2+}$ is one of the most abundant divalent cations in mammalian body(0.2~1.0mM) and the important physiological roles are : first, the cofactor of many enzyme activities, second, the regulator of glycolysis and DNA synthesis, third, the important role of bioenergetics by regulating of phosphorylation, fourth, the influence of cardiac metabolism and function. In this work we have investigated the regulation of the $Mg^{2+}$ induced by ${\alpha}_1-adrenoceptor$ stimulation in perfused guinea pig hearts and isolated myocytes. The $Mg^{2+}$ content of the perfusate or the supernatant was measured by atomic absorbance spectrophotometry. The elimination of $Mg^{2+}$ in the medium increased the force of contraction of right ventricular papillary muscles, and the left ventricular pressure. Phenylephrine also enhanced the force of contraction in the presence of $Mg^{2+}-free$ medium. ${\alpha}_1-Agonists$ such as phenylephrine and methoxamine were found to induce $Mg^{2+}$ efflux in both perfused hearts and myocytes. These effects were blocked by prazosin, an ${\alpha}_1-adrenoceptor$ antagonist. The $Mg^{2+}$ influx could also be induced by phenylephrine and R59022, a diacylglycerol kinase inhibitor. In the presence of protein kinase C(PKC) inhibitors, phenylephrine produced an increase in $Mg^{2+}$ efflux from perfused hearts. Furthermore, $Mg^{2+}$ efflux by phenylephrine was amplified by phorbol 12-myristate 13-acetate(PMA). This enhancement of $Mg^{2+}$ efflux by PMA was blocked by prazosin in perfused hearts. By contrast, the $Mg^{2+}$ influx could be induced by verapamil, nifedipine, ryanodine in perfused hearts, but not in myocytes. $W^7$, a $Ca^{2+}$/calmodulin antagonist, completely blocked the phenylephrine-induced $Mg^{2+}$ efflux in perfused hearts. In conclusion, $Mg^{2+}$ is responsible for the cardiac activity associated with ${\alpha}_1-adrenoceptor$ stimulation. The mobilization of $Mg^{2+}$ is decreased or increased by ${\alpha}_1-adrenoceptor$ stimulation in guinea pig hearts. These responses may be related specifically to the respective pathways of signal transduction. A decrease in $Mg^{2+}$ efflux by ${\alpha}_1-adrenoceptor$ stimulation in hearts can be through PKC dependent and intracellular $Ca^{2+}$ levels.

• Korean Journal of Veterinary Research
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• 제46권3호
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• pp.279-284
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• 2006

Photo-catalytic products have been widely used at home and hospital to prevent bacteria, virus and fungus. Activities of anti-bacteria, anti-viruses and anti-fungi are based upon direct contact of crystals and particles of titanium dioxide with pathogens, into which titanium is catalyzed by photo. Those antimicrobial activities of the photo-catalytic titanium dioxide have been proved in vitro. However, in vivo tests of those activities have not been carried out on dog skin. Aim of this study was to evaluate the antimicrobial activities of the catalytic titanium dioxide in vivo. Ten beagle dogs were divided into two groups. One group was sprayed with 10ml of titanium dioxide(1 mg/ml) whereas the other was not. The treated dogs were exposed under the sunlight for 120 min. A set of three hairs was taken 15, 30, 60 and 120 min after the exposure and the bacteria contaminated in hairs were amplified in, Muller Hilton broth at $35^{\circ}C{\pm}1$ for 3 h. The supernatant of the bacterial culture was diluted 1 : 10 in phosphafe-buffered saline. One milliliter of the diluents was transferred into triphenyltetrazolium medium(TTC) and incubated at $35^{\circ}C{\pm}1$ for 2 days. The number of bacteria was counted. The number of bacteria colonies was decreased compared to control group. To further investigate the longevity effect of titanium dioxide, the dogs were kept in indoor without sun light for 6 and 12 h, 1, 2, 3, 7, 14 days after exposure of the chemical during each 15, 30, 60 min. The number of bacteria colony in 1ml was counted. The number of bacterial colonies was decreased. Treated group is exposured by sun light during 15 min, the longevity effect of titanium dioxide is continued by 1 week. Treated group is exposured by sun light during 30, 60 min, the longevity effect of titanium dioxide is continued over 2 weeks. These data indicated that the photo-catalytic titanium dioxide may be used for prevent bacteria on dog skin.

• Journal of Life Science
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• 제17권1호
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• pp.31-38
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• 2007

Infection with virulent or attenuated Salmonella typhimuriumhas known to induce reduction in proliferative responses of spleen cells. We investigated a role of lipid A from S. typhimurium, a B cell mitogen, on proliferation of spleen cells by T cell mitogens such as concanavaline A and phytohemagglutinin under in vitro and ex vivo conditions. Lipid A alone induced proliferation of spleen cells in vitroin a dose-dependent manner. However, subsequent treatment of concanavaline A or phytohemagglutin in after lipid A treatment induced proliferation suppression of murine spleen cells in vitro and ex vivo. Removal of macrophages from spleen cells, which were obtained from a lipid A-injected mouse, restored proliferation by concanavaline A and phytohemagglutinin, indicating that macrophages appeared to play a role in lipid A-induced suppression. Secreted molecules from macrophages did not accounted for the suppression because suppressive effect was not achieved when the supernatant from macrophage-containing spleen cell culture was conditoned to macrophage-depleted spleen cell culture. Co-culture of spleen cells from lipid A-treated and - untreated mice showed proliferation suppression as increasing cell numbers of lipid A-treated mouse. These data suggested that the cell-to-cell contact of macrophage with splenic lymphocyte cells is responsible for immune responses against lipid A, which is applicable to the case of human S. typhi infection.

• Journal of Life Science
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• 제25권2호
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• pp.180-188
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• 2015

The bacterial strain isolated from Kimchi showed antibacterial activity against Micrococcus luteus IAM 1056. The selected strain was identified as Lactococcus lactis by 16S rRNA nucleotide sequence analysis and named as Lactococcus sp. KD 28. The treatment of culture supernatant with proteinase K removed antibacterial activity, indicating its proteinaceous nature, a bacteriocin. This bacteriocin was sensitive to hydrolytic enzymes such as ${\alpha}$-chymotrypsion, trypsin, proteinase K, lipase, ${\alpha}$-amylase and subtilisin A. The bacteriocin was highly thermostable and resistant to heating at $80^{\circ}C$ for up to an hour but 50 % of the total activity was remained at $100^{\circ}C$ for 30 min. The pH range from 2.0 to 8.0 had no effect on bacteriocin activity and it was not affected by solvents such as acetonitrile, isopropanol, methanol, chloroform and acetone up to 50% concentration. The bacteriocin showed antibacterial activity against M. luteus IAM 1056, Lactobacillus delbrueckii subsp. lactis KCTC 1058, Enterococcus faecium KCTC 3095, Bacillus cereus KCTC 1013, B. subtilis KCTC 1023, Listeria ivanovii subsp. ivanovii KCTC 3444, Staphylococcus aureus subsp. aureus KCTC 1916, B. megaterium KCTC 1098 and B. sphaericus KCTC 1184. The bacteriocin was purified through ammonium sulfate concentration, SP-Sepharose chromatography and RP-HPLC. The molecular weight was estimated to be about 3.4 kDa by tricine-SDS-PAGE analysis.