• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.265-266
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• 2001

PCDDS and PCDFs are very stable chcmicals and have very long residence times in the environment and in organisms, including humans. Their hydrophobicity promotes accumulation in sediments and organisms, resulting in high concentrations in both sediments and organisms. Among toxicological effects reports arc teratogenicity, reduce reproduction, liver toxicity, decreased growth rate and behavioral changes (Zeise et al., 1990; Huff, 1992). PCDDs/DFs are inadvertently produced from various combustion sources and manufacturing processes, such as municipal solid waste incineration (Olie et at., 1977), motor vehicles (Marklund et al., 1987), steel mills (Tysklind et al., 1989), and chemical production processes (Hutzinger et al., 1985). (omitted)

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.16-20
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• 2003

A phylogenetic analysis of bacterial populations inhabiting soil derived from serpentine was conducted. The samples were collected from adjacent metamorphic rocks and serpentinite soil at Kwangcheon. The pH of the serpentine areas ranged from 8.5 to 9.2. The number of bacteria on the DAL medium which was diluted with $10^{-2}$ of AL medium was 10~100 fold higher than that from the full strength of AL medium, and which indicates that oligotrophs are distributed in the serpentinite soil. Of a total of 76 isolates, 42 isolates were oligotrophic bacteria, which grew only on the DAL medium. Based on a phylogenetic analysis using 16S rDNA sequences, these isolates are found to fall within five major phylogenetic groups: proteobacteria $\alpha$-subdivision (3 strains), $\alpha$-subdivision (7 strains), $\gamma$-subdivision (2 trains); high G+C gram-positive bacteria (19 strains); low G+C grampositive bacteria (14 strains). Bacteria of the genus Streptomyces (high G+C division) and Bacillus (low G+C division) have been considered to form a numerically important fraction of serpentinite soil. Oligotrophic strains categorized as Afipia ($\alpha$-subdivision), Ralstonia, Variovorax ($\beta$-subdivision), Pseudomonas ($\gamma$ -subdivision), Arthrobacter (high G+C division), and Streptomyces (low G+C division).

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.371-375
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• 1999

AL072 is a potent anti-Legionella antibiotic produced by Streptomyces strain AL91. The minimum inhibitory concentration (MIC) of AL072 against Legionella pneumophila was 0.2$\mu$g/ml. Bacterial growth was rapidly inhibited at the dose range between the MIC and 20 times of the MIC when the antibiotic was added at the mid-exponential phase. Ultrastructural changes in L. pneumophila were observed upon treatment with AL072. Under electron microscopical observation, the organisms treated with AL072 exhibited characteristic morphological changes in the cellular outer coat. Also irregular morphological changes, such as the formation of filamentous materials in the cytoplasm, an increase in the size and number of cytoplasmic vacuoles, the extruding of cytoplasmic contents, the formation of spheroplast and ghost cells, and blebbings in the cell wall were observed. Furthermore, immunoelectron microscopical observation of the group treated with the MIC showed that the immune complex attached mainly to the cell wall. The results of these experiments indicate that AL072, like the inhibitors of cell wall synthesis, act selectively on the cell wall of L. pneumophila.

• Journal of Microbiology
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• v.33 no.2
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• pp.95-102
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• 1995

A probability identification matrix of acidophilic Streptomyces was constructed. The phenetic data of the strains were derived from numerical classification described by Seong et al. The minimum number of diagnostic characters was determined using computer programs for calculation of different separation indices. The resulting matrix consisted of 25 clusters versus 53 characters. Theoretical evaluation of this matrix was achieved by estimating the chuster overlap and the identification scores for the Hypothetical Median Organisms (HMO) and for the representatives of each cluster. Cluster overlap was found to be relatively small. Identification scores for the HMO and the randomly selected representatives of each cluster were satisfactory. The matrix was assessed practically by applying the matrix to the identification of unknown isolates. Of the unknown isolates, 71.9% were clearly identified to one of eight clusters. The numerical classification data was also used to design a selective isolation medium for antibiotic-producing organisms. Four chemical substances including 2 antibiotics were determined by the DLACHAR program as diagnostic for the isolation of target organisms which have antimicrobial activity against Micrococcus luteus. It was possible to detect the increased rate of selective isolation on the synthesized medium. Theresults show that the numerical phenetic data can be applied to a variety of purposes, such as construction of identification matrix and selective isolation medium for acidophilic antinomycetes.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.90-91
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• 2000

The physiological systems that control blood fluidity are both complex and elegant. Blood must remain fluid within the vasculature and yet clot quickly when exposed to nonendothelial surfaces at sites of vascular injury. There are two principle mechanisms to control a delicate balance in higher organisms (Davie & Ratnoff, 1964). Present evidence suggests that the intrinsic pathway play an important role in the growth and maintenance of fibrin formation in the coagulation cascade while a second overlapping mechanism, called the extrinsic pathway, is critical in the initiation of fibrin formation. Coagulation factors is in two mechanisms, and in order to clot blood, they are activated by a cooperation with $Ca^{2+}$, phospholipid and vitamin K etc. For example, the human placental anticoagulant protein (PAP of PAP- I), which is a $Ca^{2+}$ -dependent phospholipid binding protein (Funakoshi et al., 1987) inhibited the activity of factor Xa, so that it prolonged fibrin formation. We wondered whether any other protein was involved in regulation of the coagulant system as an anticoagulant protein from natural organisms. Natural agents would have not harmful side-effects in comparision with chemically synthesized materials such as warfarin, aspirin, phenindione, etc.. But anticoagulant agents from natural, especially marine organisms have hardly been researched except for polysaccharides from marine algae. (omitted)

• Advances in nano research
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• v.3 no.4
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• pp.243-255
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• 2015

In this investigation, ecotoxicity of nano and micro metal oxides, namely silica ($SiO_2$) and alumina ($Al_2O_3$), on the growth of green algae (Porphyridium aerugineum Geitler) is discussed. Effects of nano and micro particles on the growth, chlorophyll content and protein content of algae are analysed using standard protocols. Results indicate that $SiO_2$ nano and micro $SiO_2$ particles are non-toxic to P. aerugineum Geitler up to a concentration of 1000 mg/L. In addition, $Al_2O_3$ microparticles are less toxic to P. aerugineum Geitler, whereas $Al_2O_3$ nanoparticles are found to be highly toxic at 1000 mg/L. Moreover, $Al_2O_3$ nanoparticles decrease the growth, chlorophyll content, and protein content of tested algae. In addition, zeta potential and contact angle are also important in enhancing the toxicity of metal oxide nanoparticles in aquatic environment. This study highlights a new insight into toxicity evaluation of nanoparticles on beneficial aquatic organisms such as algae.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.232-233
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• 2002

In recent years devastation on coasts worldwide has led to barren grounds resulting in the loss of the natural population of many marine organisms and macrophytes. Furthermore, fishery resources such as abalone, fish and seaweeds have been depleted (Serisawa and Ohno, 1995). Since 1980, many fishery scientists and phycologists have tried to create artificial seaweed beds using various technique in order to recover lost seaweed beds (Ohno, 1993; Choi et al., 2000). (omitted)

• The Microorganisms and Industry
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• v.17 no.1
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• pp.10-18
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• 1991

A phylogenetic comparison of homologous protein can often supplement genetic and biochemical analysis by revealing conserved structures that are critical for function(Waugh et al., 1989). I therefore isolated a secY homologue from B. subtilis, a gram positive bacterium evolutionary distant from E. coli. The comparison and interplay between these two bacterial systems should contribute greatly to our understanding of the functions and interactions within systems evolved for protein translocation in both prokaryotic and eukaryotic organisms.

• Environmental Analysis Health and Toxicology
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• v.14 no.4
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• pp.155-163
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• 1999

Heavy metal accumulation in living organisms through food-wed can give serious damage on physiological responses for vital activities. The initiation of heavy metal supposed to begin from the bio-accumulation of plants. To establish basic data fur heavy metal contents in plants at the area without artificial contamination, both woody and herb plants at Mt. Kwang-Duk were studied. The content of heavy metals in various organs of plants were analyzed by ICP. The range of heavy metals in plants for Al, As, Cd, Co, Cr, Cu, Fe. Mn, Pb, Se and Zn were 1.019∼257.200ppm, O∼2.929ppm, 0∼0.079ppm, 0∼0.054ppm, 0.023∼3.007ppm, 0∼1.997ppm, 2.031∼148.500ppm, 1.069∼51.320ppm, O∼126.900ppm, 0.708∼4.927ppm and 0.846∼4.949ppm, respectively. The amount of heavy metals in plants are much less than that of soil except some species. In woody plants, it was detected that the metal contents of leaves were higher than that of stems especially in case of Al and Fe with statistical significance. There were significant differences between shoots and roots of herb plants in metal content of Al, Co and Fe. Those metals have more accumulated in roots comparing with shoots. Some species of plants had shown the difference tendency of heavy metal accumulation. Generally, most species had not exceeded over twice of mean value each other, and had various difference according to the kinds of heavy metals.

• Carbon letters
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• v.8 no.3
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• pp.191-198
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• 2007

Recent studies have revealed the poisonous nature of aluminum(III) species to aquatic and terrestrial organisms. Therefore, this investigation aims to develop batch adsorption experiments in the laboratory, aiming to the removal of aluminum(III) from aqueous solutions onto powdered activated carbon (PAC). The latter (which is an effective and inexpensive sorbent) was prepared from olive stones generated as plant wastes and modified with an aqueous modifying oxidizing agent, viz. $HNO_3$. The main parameters (i.e. initial solution pH, sorbent and $Al^{3+}$ ions concentrations, stirring times and temperature) influencing the sorption process were examined. The results obtained revealed that the sorption of $Al^{3+}$ ions onto PAC is endothermic in nature and follows first-order kinetics. The adsorption data were well described by the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) adsorption models over the concentration range studied. Under the optimum experimental conditions employed, the removal of ca. 100% $Al^{3+}$ ions in the concentration range $1.35-2.75\;mg{\cdot}l^{-1}$ was attained. Moreover, the procedure was successfully applied to the recovery of aluminum spiked to some environmental water samples with an RSD (%), does not exceed 1.22%.