• Journal of Life Science
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• v.5 no.2
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• pp.25-25
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• 1995

The antitumor activities of the cell bound polysaccharide(CBP), water soluble polysaccharide(WSP) and sulfated polysaccharide(SP) of Zoogloea sp. were observe. The results obtained were as follows : 1) The CBP, WSP, and SP showed cytotoxic effect on the Meth A cells in vitro, however, the effect of CBP and WSP was more ten-fold greater than that pf SP. 2) When CBP, WSP, and SP was inoculated into the peritoneal cavity of the Meth A cells transplanted mice, the average survival days tended to prolonged slightly as compared with the control. 3) When Meth A cells were transplanted subcutaneously into the back side of mice, and then CBP, WSP, and Sp was inoculated into the peritoneal cavity of mice, the tumor growth inhibition ratio was 46.9% for WSP, 40.4% for CBP, and 16.2% for SP. 4) The phagocytic activity of peritoneal macrophages elicited with CBP, WSP, and SP was significantly increased than that of control. 5) The production of nitric oxide in the peritoneal macrophages stimulated with CBP, WSP, SP, and LPS aloneo was not increased than that of control. The production of nitric oxide in the peritoneal macrophages stimulated with IFN-r and CBP, IFN-r and WSP and IFN-r and SP was significantly increased than that of control, but in the case of stimulated with IFN-r and WSP was increased 50% for CBP and SP. These results suggest that the CBP, WSP and SP of Zoogloea sp. showed direct cytotoxic effect and tumor growth inhibition on Meth A cells in vitro and in vivo, and induced nitric oxide production of activated macrophages.

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.333-338
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• 2012

Lichens are a symbiosis between fungi, algae and cyanobacteria. Our group recently studied the antioxidant properties of some bacterial species isolated from Arctic lichens and we confirmed that they possess high antioxidant activities. In this paper, we investigated the antioxidant capacity of 5 microorganisms newly isolated from 4 Arctic lichen species, Cladonia sp., Sterocaulon sp., Umbilicaria sp. and Cetraria sp., using various solvent extractions. We carried out 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2'-azino-bis(3-ethyl benzothiazoline-6-sulphonic acid) (ABTS) free radical scavenging activity test and ferric reducing antioxidant power (FRAP) assay. Also total phenolic and flavonoid content assays were performed. Among the bacterial culture extracts of the tested lichen-microorganisms, ethyl acetate extracts of Burkholderia sordidicola S5-B(T) had not only a high antioxidant activity (72.9%) when compared with the ascorbic acid used as the control (51.3%) in the DPPH assay, but also a high amount of phenolic content as well as flavonoid content. As a result, these lichen-microorganisms may be potentially useful sources of natural antioxidants.

• Microbiology and Biotechnology Letters
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• v.7 no.1
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• pp.15-21
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• 1979

In order to find out a reliable chemical indicator which can be used to tell whether rice, during storage, is invaded by fungi or not, 90 percent milled rice (Tongil) was stored at 26$^{\circ}C$ for 4 weeks and weekly analyzed for changes in several chemical components. The results were as follows : 1) Of several genera of fungi (Aspergillus sp., Penicillium sp., and Rhizopus sp.) observed in stored rice after surface disinfection, Aspergillus sp. were the most frequent fungi. 2) Chitin content in the rice was 25 ug/g at the beginning of the experiment and increased proportionly with moisture content of the storedrice to become 1980 ug/g at 26.9％ moisture after 4 weeks. 3) Non-reducing sugartended to decrease with increasing moisture content and or prolonged period. 4) Fat acidity showed a tendency of increase with rise in moisture content of the stared rice. Consequently, changes in chitin content can be mployed as a reliable measure to evaluate the quality of stored rice in connection with fungal invasion.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.99-105
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• 2002

A gregarious pupal endoparasitoid Tetrastichsus sp. (Hymenoptera: Eulophidae) was reared in vitro from oviposition to adult emergence on an artificial host. The host pupal case was made using 0.02 mm-thick polypropylene film, and was filled with a diet consisting of powders of Antheraea pernyi pupa, chicken yolk, infant formula, royal jelly, and Neisenheimer's salt solution. Female parasitoids reared in the artificial host produced smaller sized progeny than those reared in in vivo, but the adults reproduced fertile offsprings. Furthermore in vitro second-generation (G$_2$) females showed more improved biological characteristics, compared with their parents. The fecundity (mean no. adult progeny), oviposition period (days), and longevity (days) of G$_2$ female were evaluated as 45.7, 7.8, and 13.8, respectively Female biased sex ratio was obtained with 76.9% female progeny. The results demonstrated that Tetrastichus sp. is a promising parasitoid for in vitro mass production.

• KSBB Journal
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• v.11 no.5
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• pp.586-592
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• 1996

Poly(3-hydroxybutyric-co-3-hydroxyvaleric) acid(PHB/HV) copolymer synthesis by Pseudomonas sp. HJ from glucose and cosubstrate was investigated. Taxonomic analysis suggested that Pseudomonas sp. HJ was best marched to Pseudomonas picketti having 78.8% similarity. Pseudomonas sp. HJ produced PHB/HV copolymer containing 60.8 mol% HV and 44.9 mol% HV when supplied with hexadecane and propionic acid as a cosubstrate, respectively. The HV composition in PHB/HV copolymer was controlled by varying the concentration of hexadecane and propionic acid. Propionic acid added after 24 hours of incubation was incorporated as the HV monomer in the PHB/HV copolymer up to 49.6 mol%.

• Journal of Electrochemical Science and Technology
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• v.9 no.1
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• pp.44-50
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• 2018

The aims of this study were to determine the corrosion behavior of pure copper in the presence of Desulfovibrio sp. and also to investigate the effects of glutaraldehyde (GD) and isothiazolinone (ISO) on the corrosion behavior of pure copper in the presence of this sulfate-reducing bacteria (SRB) strain by using electrochemical techniques. Electrochemical measurements of pure copper were carried out at specified time intervals (0, 8, 24, 48, and 96 hr) over a period of exposure. Corrosion rates of pure copper from anodic and cathodic Tafel slopes and corrosion potential ($E_{corr}$) were determined. Biofilm and corrosion products on the copper surfaces were observed by Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-Ray Spectrometry (EDS) analyses. The effects of solution types (PC (Postgate's C medium) and SRB (Desulfovibrio sp.)) and exposure times of copper and biocides (ISO or GD) on the corrosion rates of pure copper were evaluated by statistical analyses. As a result of the FESEM analysis, biofilm formation was observed on the surfaces of pure copper exposed to the Desulfovibrio sp. cultures both with and without the biocides. The results show that the pure copper was corroded by Desulfovibrio sp. However, the addition of GD or ISO to the Desulfovibrio sp. culture resulted in a decrease in the corrosion rate of the pure copper. It was also observed that both of the biocides showed a similar effect on pure copper's corrosion rate caused by Desulfovibrio sp.

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.17-24
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• 2019

Bacteria in the polar region are under strong light and ultraviolet radiation. In this study, we investigated the effects of light on the growth of a psychrophilic bacterium, Sphingomonas sp. PAMC 26621, isolated from an Arctic lichen Cetraria sp. The growth of the strain in the light was lower than that in the dark. Surprisingly, thiamine increased the growth of Sphingomonas sp. PAMC 26621 in M9 minimal medium under light conditions. Thiamine increased the growth of the strain in a concentration-dependent manner along with ascorbic acid. N-acetylcysteine had no effect on the growth of the strain in the light. Thiamine and ascorbic acid also increased the activities of glucose-6-phosphate dehydrogenase and superoxide dismutase. The results of this study indicate that thiamine provided by the lichen symbiosis system plays an important role in light-induced oxidative stress in this Arctic bacterium as an antioxidant. Our study provide insight into the biochemistry and physiology of Arctic bacteria under strong light and ultraviolet radiation.

• Journal of Environmental Science International
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• v.17 no.10
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• pp.1121-1127
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• 2008

The free-living amoeba and Acanthamoeba sp. are widely distributed in fresh water, soil, air and dust in the world. We studied distribution of amoeba from low Nakdong River(Mulgum and Maeri) and removal efficiency in water treatment process of Busan metropolitan city. During this investigation, water quality showed pH $7.4{\sim}9.6({\pm}1.1)$, water temperature $2.0{\sim}29.0({\pm}17)^{\circ}C$, turbidity $4.8{\sim}27.4({\pm}11.0)$ NTU, chlorophyll-a $10.3{\sim}109.0({\pm}44.3)\;mg/m^{3}$, BOD $1.7\sim4.9({\pm}2.6)$ mg/L, COD $3.1\sim-6.9({\pm}5.0)$ mg/L and total coliform $17\sim920({\pm}200.5)$ MPN/100 mL. The free-living amoeba were detected highly than Acanthamoeba sp., 11 out of 22 in raw water samples were positive (50%) for Acanthamoeba sp. from February 2005 to December 2005. The seasonal characteristics of tree-living amoeba and Acanthamoeba sp. in raw water were mainly distributed through the spring to the early fall. When tree-living amoeba and Acanthamoeba sp. were passed through the water treatment of pilot-plant, approximately 80% was sure to be removed through pre-ozonation, sedimentation, send filtration. 100% was removed after post-ozonation process. All of the isolated amoebas from Nakdong River were Acanthamoeba sp. AC311 18S ribosomal RNA gene with 98% nucleotide sequence homology.

• Parasites, Hosts and Diseases
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• v.26 no.2
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• pp.121-126
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• 1988

Efficacy of praBiquantel (CesocideB injection) by intramuscular (1.M.) route against cestode infections was evaluated. Total 93 domestic or laboratory animals such as dogs, cats, rats, mice, goats, deers and chickens were used. Animals were infected with Dipylidium caninum, Spirometra sp. , Taenia pisiformis, Taenia taeniaeformis, Hymenolepis nana, Moniegia expanse, Moniexia sp. or Raillietina sp. A single dose of prasiquantel, 6 mg/kg of body weight, was highly effective (97.9%) against cestodes of various kinds disregarding the host species or their intensity of infection. At higher dose above 6 mg/kg, the cure rate was 100%. All the cestodes treated were expelled from the host within 48 hours. The discharged proglottides were damaged severely except Hymenolepis nana and Moniegia expanse. Intramuscular injection of this drug evoked a brief pain response in a dog, but no other side reactions were observed.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.369-374
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• 2016

Bacillus velezensis YP2 inhibited the mycelial growth of several plant pathogens including Cercespora spp., Septoria sp., Phoma sp., Botrytis cinerea and Sclerotinia scleotiorum occurring in leafy vegetables. Control efficacy for powdery mildew caused by Erysiphe cruciferarm on red leaf mustard and cheong mustard by treatment of spraying with 10-fold diluted Luria-Bertani (LB) broth of B. velezensis YP2 was 91.8% and 80.9%, respectively. When B. velezensis YP2 was treated four times with five-day interval, three times at seven-day interval and two times at ten day interval in the greenhouse test, the control effect of red leaf mustard powdery mildew was 70.6%, 65.0% and 40.9%, respectively. Also B. velezensis YP2 could promote the seed germination and plant growth of led leaf mustard. The results showed that the culture broth of B. velezensis YP2 was very effective to control the powdery mildew of leaf mustard.