• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.563-569
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• 2001

In order to utilize the processing wastes of squid, chitosan was prepared by intermittent deacetylation treaoent of $\beta-chitin$ contained richly in the pen of squid. Acetylchitosan also was synthesized from squid pen chitosan with anhydrous acetic acid and their characteristics were investigated. The amounts of nitrogen and ash of squid pen chitosan were $5.80.2\% and 0.2\pm0.03\%$ respectively, the yield of squid pen chitosan was $25\pm3\%$, the degree of deacetylation was $92\%$, and the molecular weight was $1.15\times10^6$, Acetyl contents of N-acetylchitosan powder, acetylchitosan bead, N-ACF-1 (N-acetylchitosan film-1) and N-ACF-2 (N-acetylchitosan film-2) were $55.9\%, 63.2\%, 56\% and 58.7\%$ respectively. Two major peaks, amide I ($1,653 cm^{-1}$) and II ($1,558 cm^{-1}$) bent, on FT-IR spectra of the N-acetylchitosan from squid pen were almost similar to these of $\beta-chitin$, While there was a broad single peak at $1,601 cm^{-1}$assigned to be an amide I bend in squid pen chitosan. The CP/MAS NMR spectra of $\beta-chitin$, squid pen chitosan and N-acetylchitosan from squid pen showed a relative broad and single peak at 74 ppm assigned to fifth carbon (C-5) and third carbon (C-3). In case of $\beta-chitin$ and N-acetylchitosan from squid pen, single peak at 74 ppm was showed as the same of $\beta-chitin$ type.

• Journal of Korea Soil Environment Society
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• v.5 no.1
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• pp.33-43
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• 2000

For the consideration of phytoremediation, TEX>$Cd^{2+}$ and Pb$^{2+}$ were analysed in the soil of the habitats and the leaf stem and root of Persicaria thunbergii in the different localities of Bong-Dong river In the soil and plant samples of research areas, TEX>$Cd^{2+}$ was not detected but, $Pb^{2+}$ detected as follows; about 7.5~15.5$mu\textrm{g}$/g in the soil of habitats, about 11.7~18.4 $mu\textrm{g}$/g in the leaf, about 7.~15.5$mu\textrm{g}$/g in the stem and about 89.1~193.6$\mu\textrm{g}$/g in the root of P. thunebrgii and the correlation coefficient value between the $Pb^{2+}$ contents in soil and P. thunbergii was 0.814(>t12, 0.01). After P thunbergii was treated with Cd(NO$_3$)$_2$and Pb(NO$_3$)$_2$of 5 and 10mM, the bioaccumulation of TEX>$Cd^{2+}$ and $Pb^{2+}$ in the leaf of plant, the remaining mass of heavy metals and the variation of pH in the soil, and the increasing rate(%) of phytochelatin in plant were examined. The concentrations of TEX>$Cd^{2+}$and $Pb^{2+}$ in the leaf as follows, in the case of TEX>$Cd^{2+}$ about 0.82~2.79$\mu\textrm{g}$/g and in $Pb^{2+}$, about 2.87~8.08$\mu\textrm{g}$/g. The remaining mass of heavy metals and the variation of pH in the cultured soil decreased as follows; about 77.1% and pH6.39 in TEX>$Cd^{2+}$ 5mM, about 90.2% and pH5.79 in TEX>$Cd^{2+}$ 10mM, about 81.1% and pH6.00 in $Pb^{2+}$ 5mM and about 85.7% and pH5.80 in Pb$^{2+}$ 10mM. The phytochelatin were increased in plant samples treated with 10mM Cd(NO$_3$)$_2$and Pb(NO$_3$)$_2$as follows; about 259% by TEX>$Cd^{2+}$ and about 305% by Pb$^{2+}$ be compared with control. and the molecular weight(da) of these phytochelatins were estimated about 4,300~8,600da in the case of the treatment of TEX>$Cd^{2+}$ and about 3,200~9,700 in $Pb^{2+}$./TEX>.

• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.123-132
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• 1982

These experiments were conducted to investigate the enzymatic characteristics of the purified $\alpha$-amylase (F-2A) of Bacillus circulans F-2 and the digestion rate of various starches. 1. The molecular weight was estimated to be 93000 by SDS-polyacrylamide disc gel electrophoresis. The isoelectric point was about pH 5.0. The optimum pH for the enzyme action was 6.0-6.5 and the stable pH ranged pH 5.5-12.0. The optimum temperature was 6$0^{\circ}C$, and the purified $\alpha$-amylase was stable below 4$0^{\circ}C$. 2. The purified $\alpha$-amylase was activated by Mn$^{＋＋}$ and Co$^{＋＋}$, whereas it was inhibited by Ag$^{＋}$, HT$^{＋＋}$, Cu$^{＋＋}$ and Pb$^{＋＋}$. 3. The purified $\alpha$-amylase is considered to have no sulfhydryl residue essential for its catalytic activity. 4. Michaelis constant (Km) was 1.704 mg/$m\ell$. Activation energy between 25-4$0^{\circ}C$ was 12.297 Kcal/mole, and between 40-6$0^{\circ}C$, it was 7.831 Kcal/mole. 5. The hydrolysis product from soluble starch, amylose and amylopectin in the early stage of hydrolysis was G$_{6}$, and as hydrolysis proceeds, G$_4$and G$_2$appeared. 6. Products from each oligosaccarides are as follows: G$_4$longrightarrow G$_2$＋ G$_2$,G$_3$ ＋G$_1$,G$_{5}$longrightarrow G$_4$＋G$_1$,G$_{6}$longrightarrowG$_4$＋ G$_2$,G$_{7}$ G$_4$,G$_{8}$longrightarrow G$_4$＋G$_4$, 7. On raw potato starch, raw sago starch and raw yam starch, the purified enzyme exhibited a remarkably high digestion rate than Porcine pancreatic amylase and Streptococcus bovis amylase.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.355-362
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• 2016

The phosphomannomutase/phosphoglucomutase gene (pmm/pgm) of Vibrio anguillarum (the causative agent of fish vibriosis) was cloned, and the open reading frame corresponded to a protein with 446 amino acids. The pmm/pgm gene showed a significant degree of sequence homology with the previously reported genes from V. mimicus, V. vulnificus, V. splendidus, and V. harveyi, with 92.3%, 91.4%, 89.9%, and 89.9% amino acid identity, respectively. By reverse transcriptase-polymerase chain reaction, we found that the pmm/pgm gene was upregulated under cold stress condition. The PMM/PGM protein is known to catalyze the interconversion between mannose-1-phosphate and mannose-6-phosphate or glucose-1-phosphate and glucose-6-phosphate, which are important intermediates for lipopolysaccharide (LPS) biosynthesis. To confirm the role of PMM/PGM in the LPS biosynthetic pathway, we constructed a knock out mutant by homologous recombination. The respective LPSs were isolated from the V. anguillarum wild-type and mutant strains, and changes were compared by subjecting them to sodium dodecyl sulfate polyacrylamide gel electrophoresis. Based on the different patterns of the LPSs, we expect the pmm/pgm gene to have an important role in LPS biosynthesis. The pmm/pgm-deficient mutant of V. anguillarum will contribute to further studies about the role of LPS in V. anguillarum pathogenesis.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.8
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• pp.950-955
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• 2007

Non-point source control system which had been designed only for oil-water separation in the fields of oil refinery and garage was upgraded in this research for the removal of runoff pollutants in impervious urban area. Pollutants including oil from driveway and bridge were eliminated by two types of pathway in the system. One is the coalescence mechanism that the oil droplets in the runoff come into contact with each other in the spiral buoyant media surface and form larger coalesced droplets of oil that are carried upstream to the oil layer. The other is the precipitation that solids in runoff were settled by gravity in the system. In this research, coalescing characteristics of oil and water separation were investigated through image analyses, and efficiencies of the non-point source control system were evaluated using dust in driveway and waste engine oil. Media made of high density and high molecular weight polyethylene was indeterminate helical shape and had sleek surface by analysing SEM photographs and BET. Surface area and specific gravity of media which were measured directly were 1,428 $mm^2$ and 45.3 $kg/m^3$ respectively. From the image analyses of the oil droplets photographs which were taken by using microscope, it was proved clearly that the coalescence was the main pathway in the removal of oil from the runoff. Finally, the performances of the non-point source control system filled up with the media were suspended solid $86.6\sim95.2%$, $COD_{Cr}$, $87.3\sim95.4%$, n-Hexane extractable materials $71.8\sim94.8%$ respectively.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.125-136
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• 1994

To characterize the SR Ca-release channel protein complex of crustacean, $^{45}Ca-release,\;[^3H]ryanodine$ binding, and immunoblot studies were carried out in the crayfish and/or lobster skeletal sarcoplasmic reticulum. Bmax and affinity of crayfish SR to ryanodine were lower than those of lobster SR. AMP (5mM) increased $[^3H]ryanodine$ binding significantly in both vesicles (P<0.05). $Mg^{2+}$(5mM) or tetracaine(1mM) inhibited $[^3H]ryanodine$ binding significantly in both vesicles (P<0.001), but ruthenium red $(10\;{\mu}M)$ inhibited it moderately. In SDS polyacrylamide gel electrophoretic analysis of crayfish SR vesicles, there was a high molecular weight band that showed similar mobility with Ca-release channel protein of lobster skeletal SR, but more rapid mobility (HMWBr) than that of rabbit skeletal SR (HMWBS). Immunoblot analysis showed that polyclonal Ab to lobster skeletal SR Ca-release channel protein was react with HMWBr of crayfish skeletal SR, but not with that of HMWBs of rabbit skeletal SR. ^{45}Ca-release from crayfish skeletal SR vesicles was increased by the increase of extravesicular calcium from $1{\mu}M$ to 1mM. This Ca-release phenomenon was similar, but more sensitive in the low concentration of $Ca^{2+}$, compared to that from lobster SR vesicles. AMP (5mM) or caffeine (10mM) did not affect to $^{45}Ca-release.\;^{45}Ca-release$ was inhibited slightly ($3{\sim}8%\;by\;Mg^{2+}$) (5mM) or tetracaine (1mM), and moderately (23%) by high concentration of ruthenium red $(300\;{\mu}M)$. From the above results, it is suggested that SR Ca-release channel protein of crustacean has different properties from that of the rabbit, and similar properties between crayfish and lobster in functional and immunological aspects, but Ca-release via crayfish channel may be more sensitive to calcium.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.247-257
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• 2014

Assessment for operator's dermal and inhalation exposure to acetamiprid during cultivation of water melon in greenhouse was carried out. For dermal exposure measurement, whole body dosimetry (WBD) was performed as the first trial in Korea. WBD consists of cotton/polyester outer clothes and cotton inner clothes. Hand exposure was measured by washing of nitrile gloves and hands while head exposure was monitored by face/neck wipe technique. Inhalation exposure was monitored with personal air sampling pumps and IOM sampler (glass fiber filter). Analytical limit of quantitation was 2.5 ng/mL. Good reproducibility (C.V < 8.7%), linearity ($R^2$ > 0.99) and recovery (70~119%) were obtained. Field recovery of acetamiprid was 77~95%. During mixing/loading, hand exposure of acetamiprid was about 10 times ($229.7{\mu}g$) more than that of application case ($20.9{\mu}g$). During application, total dermal exposure was $1207.4{\mu}g$. Exposure of lower legs was $1132.1{\mu}g$, which is 93.8% of the total dermal exposure. Inhalation exposure during mixing/loading and application was not detected. Margin of safety (MOS) was calculated for risk assessment using male Korean average body weight (70 kg) and acceptable operator exposure level ($124{\mu}g/kg/day$) to give 140, suggesting that health risk of operator during treatment of acetamiprid for water melon in greenhouse could be safe.

• Microbiology and Biotechnology Letters
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• v.7 no.2
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• pp.75-89
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• 1979

One strain of Penicillium sp. (175-66-B), isolated from soil, was able to produce a substance that has a strong inibition activity against the Agkistrodon and Trimeresurus venoms. In this experiment, the chemical and biological properties of the sample were investigated. As an inhibitory substance, it was effective to the proteinase, hemorrhagic and lethal factors of Agkistrodon and Trimeresurus venoms, and also effective to several fractions of the proteinases and hemorrhagic factors of Agkistrodon halys blomhoffi venom. Moreover, in the addition of prednisotone, it was more effective for the cure of the mouse envenomated with the venom amount of two fold of MLD$_{100}$. This substance was very stable to the acid, alkali and heat. Its melting point was high enough to sublime at 222$^{\circ}C$ without any decomposition. This sample was easily dissolved only in hot water, but not in several organic solvents except for a little dissolution in elate. It did not have the chelating activity. It had very strong specificity to the snake venoms. but its activity was depressed by the addition of zinc or cupric salts. This sample had no acute toxicity to the mouse. Its chemical formula was $C_{16}$ $H_{12}$$N_2$ $O_{10}$ with the molecular weight of about 392. It has two epoxy groups and four carboxyl radicals, but amino, nitrite and nitrate radicals, unsaturated bonds and aromatic ring were not detected. Theuchemical configuration of this sample was suggested to be;

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.198-206
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• 2013

The five anti-complementary polysaccharides (MFKF-NP, MFKF-AP1${\alpha}$, ${\beta}$, and MFKF-AP2${\alpha}$, ${\beta}$) were separated from hot water extracts of fruiting bodies of Fomes fomentarius by two subsequent column chromatography using DEAE-sepharose FF and Concanavalin A-sepharose 4B. The order of anti-complementary activity was MFKF-AP1${\beta}$ > MFKF-AP1${\alpha}$ > MFKF-AP2${\alpha}$ > MFKF-AP2${\beta}$ > MFKF-NP > Polysaccharide Krestine (PSK). Especially, MFKF-AP1${\beta}$ among those showed the most excellent anti-complementary activity (70% of ITCH50 value at $20{\mu}g/ml$). The monosaccharide composition analysis by gas chromatography indicates that MFKF-AP1${\alpha}$ and ${\beta}$ are a kind of homoxylan consisted mainly of xylose above 97%. Molecular weight of MFKF-AP1${\beta}$, major anti-complementary polysaccharide, was estimated to be about 12,000 by high performance liquid chromatography (HPLC). After the incubation of the serum with MFKF-AP1${\beta}$ in the presence or absence of $Mg^{++}$ and $Ca^{++}$ ions, its anti-complementary activity was investigated. This result indicated that MFKF-AP1${\beta}$ seems to be activator both on the classical and the alternative pathway of complement activation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.107-113
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• 1994

Among the currently recognized pathogenic vibrios, V. vulnificus and V. cholerae non O1 are the most serious bacteria from the point of view of sea food hygiene in Korea. In this paper, the authors compared the hemolytic activities of the crude hemolysin produced by V. vulnificus and V. cholerae non O1 isolated from shellfish collected in Chungmoo, Korea. The authors also attempted to improve the purification method of V. vulnificus hemolysin(VVH) and tried to make antiserum with the purified hemolysin. VVH was produced in abundance in heart infusion broth containing $2\%$ NaCl in a shaking cultivation process(140rpm) at $37^{\circ}C$ for 15 hours. While hemolysin production patterns of V. cholerae non O1 were quite different by the strain during the culture times compared with the V. vulnificus. Hemolytic activity of the VVH on sheep erythrocytes was stronger than those of rabbit, but hemolytic activities of the hemolysin produced by V. cholerae non O1 on rabbit erythrocytes were as much as twice as strong as on those of sheep and horse. VVH was purified by two steps of hydrophobic column chromatography on Phenyl-Sepharose HP with Fast Protein Liquid Chromatography(FPLC). Purification fold and yield of VVH was much improved by changing the elution buffer's pH from 6.0 to 9.8 and adding $1\%$ CHAPS(a zwitter ionic detergent) and $50\%$ ethylene glycol to the 10mM glycine buffer during the repeated hydrophobic column chromatography. Homogeneity of the purified hemolysin was shown by polyacrylamide gel electrophoresis. According to the five times repeated purification results, the specific activity was increased 27500 times and the yield was improved by $23.4\%$ on average. About $250{\mu}g$ of purified hemolysin was harvested from the 2400ml of culture supernatant of V. vulnificus. Molecular weight of VVH was estimated to be 50KDa by the SDS-PAGE and the neutralization scores of the obtained antiserum acting against VVH were $2000{\sim}8500$.