• Microbiology and Biotechnology Letters
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• v.7 no.3
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• pp.149-155
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• 1979

Streptomyces sp. 115-5 was selected as the most active microorganism of about 200 strains for the production of chitinase. The enzyme was purified by (NH$_4$)$_2$SO$_4$ treatment, 1st-Sephadex G-100, DEAE-Cellulose, 2nd-Sephadex G-100 column chromatography, and evidence for homogenity was obtained from CM-Sephadex C-50 column chromatography and polyacylamide gel electrophoresis. The purified enzyme hydrolyzed chitin (N-acetyl glucosamine polymer) and chitosan (glucosamine polymer) but not cellulose. And with chitin as the substrate, a Km value of 3.6 mg of chitin per ml and a Vmax of 100 $\mu$mo1e fer hr were found. The activation of the chitinase was 3.66 kcal per mole. The molecular weight of the enzyme was esti-mated about 56,000 daltons by Sephadex G-100 chromatography and isoelectric point as pH 3.0.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.9
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• pp.654-659
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• 2013

This study was conducted to identify an optimal ratio of carbon to nitrogen (C/N ratio) for denitrification of nitrate using molasses as an external carbon source. A series of batch and column tests was conducted using an indigenous bacterium Pseudomonas sp. KY1 isolated from a nitrate-contaminated soil. For the initial nitrate-nitrogen concentration of 100 mg-N/L, batch test results indicated that C/N ratio of 3/1 was the optimal ratio with a relatively high pseudo-first-order reaction constant of $0.0263hr^{-1}$. At C/N ratio of 3/1, more than 80% of nitrate-nitrogen concentration of 100 mg-N/L was removed in 100 hrs. Results of column tests with a flow velocity of 0.3 mL/min also indicated that the C/N ratio of 3/1 was optimal for denitrification with minimizing remaining molasses concentrations. After 172 hrs of column operation (35 pore volumes) with an influent nitrate-nitrogen concentration of 100 mg-N/L, the effluent met the drinking water standard (i.e., 10 mg $NO_3$-N/L).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.834-841
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• 1997

A lactic acid bacteria which showed antimicrobial activity was isolated from dairy products and identified as Lactobacillus sp. according to the morphological, physiological and biochemical properties, which was named Lactobacillus sp. SH 7311. The bacteriocin of Lactobacillus sp. GM 7311 showed a broad range of inhibitory spectrum against some gram positive and negative bacteria. Especially, Proteus mirabilis was highly sensitive to bacteriocin and used as indicator strain for further investigation. The optimal condition for the production of bacteriocin was showed on MRS broth at $37^{\circ}C$ and pM 6.0. Bacteriocin production of this strain cultured under optimal condition was increased late logarithmic phase to early stationary phase. This bacteriocin was fully active at the pH range $2.0\~5.0$, also was stable at $100^{\circ}C$ for 60 min. at pH 5.0, But about $40\%$ of bacteriocin activity was diminished by the treatment of acetone, ethanol, iso-butanol and ethyl ether during 2 hours at $4^{\circ}C$.

• Journal of Life Science
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• v.28 no.9
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• pp.1056-1061
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• 2018

This article reports an agar-degrading marine bacterium and characterizes its agarase. The agar-degrading marine bacterium, KC-1, was isolated from seawater on the shores of Sacheon, in Gyeongnam province, Korea, using Marine Broth 2216 agar medium. To identify the agar-degrading bacterium as Agarivorans sp. KC-1, phylogenetic analysis based on the 16S rRNA gene sequence was used. An extracellular agarase was prepared from a culture medium of Agarivorans sp. KC-1, and used for the characterization of enzyme. The relative activities at 20, 30, 40, 50, 60, and $70^{\circ}C$ were 65, 91, 96, 100, 77, and 35%, respectively. The relative activities at pH 5, 6, 7, and 8 were 93, 100, 87, and 82%, respectively. The extracellular agarase showed maximum activity (254 units/l) at pH 6.0 and $50^{\circ}C$ in 20 mM of Tris-HCl buffer. The agarase activity was maintained at 90% or more until 2 hr exposure at $20^{\circ}C$, $30^{\circ}C$ and $40^{\circ}C$, but it was found that the activity decreased sharply from $60^{\circ}C$. A zymogram analysis showed that Agarivorans sp. KC-1 produced 3 agar-degrading enzymes that had molecular weights of 130, 80, and 69 kDa. A thin layer chromatography analysis suggested that Agarivorans sp. KC-1 produced extracellular ${\beta}$-agarases as it hydrolyzed agarose to produce neoagarooligosaccharides, including neoagarohexaose (21.6%), neoagarotetraose (32.2%), and neoagarobiose (46.2%). These results suggest that Agarivorans sp. KC-1 and its thermotolerant ${\beta}$-agarase would be useful for the production of neoagarooligosaccharides that inhibit bacterial growth and delay starch degradation.

• Korean Journal of Poultry Science
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• v.41 no.3
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• pp.165-171
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• 2014

The objective of this experiment was to investigate the effect of dietary supplementation of copper-soy proteinate (Cu-SP) and herbal mixture (HBM) on growth performance, intestinal microflora, and immune response in broiler. A total 1,000 1-d old ROSS 308 (initial $BW=41{\pm}0.38g$) were randomly allotted to 1 of 5 dietary treatments with 4 replicates during d 35 of the feeding trial. Dietary included: (1) Control : control diet, (2) Antibiotics : control diet + Avilamycin 6 ppm, (3) Cu-SP : control diet + 100 ppm Cu-soy proteinate, (4) HBM : control diet + 0.15% herbal mixture, (5) Cu-SP+HBM : control diet + 100 ppm Cu-soy proteinate + 0.2% herbal mixture. Two-phase feeding program with a starter diet from d 0 to 21, and a finisher diet from d 22 to 35 was used in the experiment. Within each phase, a diet was formulated to meet or exceed NRC requirements of broilers for macro- and micronutrients. The diet and water were available ad libitum. Result indicated that during d 22 to 35 and over all periods of the experiment, feed intake and feed conversion ratio were greater (P<0.05) for other treatment than control. Significant differences were found in lymphocyte (LY), and stress indicator (HE:LY ratio). Lymphocyte was greater (P<0.05) for Cu-SP + HBM treatment than control. However, stress indicator (HE:LY ratio) were greater (P<0.05) for control than Cu-SP + HBM treatment. The plasma IgG was higher (P<0.05) in the antibiotics, HBM, and Cu-SP+HBM treatments groups compared with control. The population of Clostridium perfringens in the antibiotics, Cu-SP, HBM, Cu-SP + HBM treatment groups were lower (P<0.05) than those control. These result suggested that dietary copper-soy proteinate or herbal mixture may be used as an alternative to antibiotics to improve growth performance, and intestinal health of birds.

• Korean Journal of Poultry Science
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• v.41 no.4
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• pp.323-329
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• 2014

The objective of this experiment was to investigate the effect of dietary supplementation of copper-soy proteinate (Cu-SP) and herbal mixture (HBM) on growth performance, blood parameter, and immune response in laying hens. A total 800 Hy-Line Brown laying hens (60 weeks old) were randomly allotted to 1 of 4 dietary treatments : (1) Control : control diet, (2) Cu-SP : control diet + 100 mg/kg Cu-soy proteinate, (3) HBM : control diet + 0.15% herbal mixture, and (4) Cu-SP + HBM : control diet + 100 mg/kg Cu-soy proteinate + 0.15% herbal mixture. Each treatment was replicated 5 times with forty birds units were arranged according to randomized block design. Feeding trial lasted 5 weeks under 16L : 8D lighting regimen. The diet and water were available ad libitum. Result indicated that during feeding trial of the experiment, hen-day egg production was significantly (P<0.05) higher in Cu-SP and HBM treated groups than control. However, feed intake, feed conversion ratio, egg weight, broken and shell less egg production were not significantly influenced by treatments. Eggshell strength was significantly (P<0.05) higher in Cu-SP than control. Eggshell thickness, eggshell color, egg yolk color, Haugh unit were not significantly influenced by treatments. The level of WBC and stress index (heterophil : lymphocyte) were higher in supplemented groups than the control. The concentration of plasma IgG was higher in supplemented groups than the control. The result of this experiment showed that dietary copper-soy proteinate or herbal mixture tended to improve egg production and affect positively on immune response of laying hens.

• KSBB Journal
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• v.15 no.2
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• pp.156-161
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• 2000

This study was designed to investigate the antioxidative activity on oxidation of human low density lipoprotein(LDL) of band 2 fractionated from culture broth of Streptomyces sp. BH-405. Antioxidative activity of band 2 obtained from fractionation of BH-405 culture purification was measured against $Cu^{2+}$ mediated human LDL oxidation by thiobarbituric acid reactive substance. $CuSO_4$ mediated oxidation of LDL was degraded at a much higher rate than native LDL. Band 2 at a concentration of 100 or 200 !lg/mL inhibited the oxidation of LDL induced by $CuSO_4$, The formation of conjugated dienes induced in the presence of 5 !1M CuS04 of the mouse macrophage and J744. The electrophoretic mobility of the LDL in addition of $200\mu\textrm{g}$ band 2 in the presence of $5\mu\textrm{m}$ $CuSO_4$ was lower than that of native LDL. LDL modified by copper mediated or cell mediated uptake was degraded by macrophage at much greater than native LDL, and band 2 was found as potential inhibitor of modification of 125I-labelled LDL by macrophage. phage.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.131-137
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• 2021

This study aimed at isolating lactic acid bacteria with anti-MRSA (methicillin-resistant Staphylococcus aureus) bacteriocin activity from fermented shrimp. We selected three strains, named Weissella sp. S1, S2, and S3, using analysis based on 16S rRNA gene sequences. All strains showed appropriate growth in an MRS medium containing 5% (w/v) NaCl and showed antibacterial activities against Bacillus cereus, Escherichia coli, Staphylococcus aureus, and MRSA. The strains exhibited similar growth rates at 0-5% NaCl, with approximate reduction in growth rate observed at 9% NaCl. Weissella sp. S1, S2, and S3 exhibited maximum growth rates at pH 7, 9, and 8, respectively. The crude bacteriocin was prepared from Weissella sp. S3 and subjected to characterization. The remaining activities after 30 min of exposure at each temperature were 100%, beyond 75%, and 49% at 4℃ and 37℃, 50℃ and 70℃, and 100℃, respectively. The remaining activities after 24 h of exposure at each pH were 100%, 75%, and 49% at pH 3 and 5, 7 and 9, and 10, respectively. Use of 50% (v/v) ethanol or isopropanol treatment did not diminish the antibacterial activity of the bacteriocin, while the 50% (v/v) hexane treatment reduced the activity by 51%. The molecular weight of the bacteriocin was nearly 6 kDa that was quantified using tricine-SDS-PAGE. Our findings suggest that Weissella sp. S3 may be considered a probiotic and useful source of antimicrobial substances in the development of bio-preservatives for food or in MRSA treatment.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.83-89
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• 2013

A bacterium, isolated from a vegetable field in a plastic film house and named strain CY6 was capable of biodegrading chlorpyrifos (CP). Based on the phenotypic features and the phylogenetic similarity of 16S rRNA gene sequences, strain CY6 was identified as a Naxibacter sp.. CP was utilized as the sole source of carbon and phosphorus by Naxibacter sp. CY6. We examined the role of this Naxibacter sp. in the degradation of other OP insecticides under liquid cultures. Parathion, methyl parathion, diazinon, cadusafos, and ethoprop could also be degraded by Naxibacter sp. CY6 when they are provided as the sole sources of carbon and phosphorus. Additionally, Naxibacter sp. CY6 ($10^8$ CFU/g) added to soil with CP (100 mg/kg) resulted in a higher degradation rate of approximately 90% than the rate obtained from uninoculated soils. These results highlight the potential of this bacterium to be used in the cleanup of contaminated pesticide soil.

• Food Science and Preservation
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• v.15 no.2
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• pp.293-299
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• 2008

Bacillus sp. SP-KSW3 is an auxothroph bacteria that is being used for starter in fermentation. Physico-chemical characteristics, enzyme activities, ACE inhibitor and antimutagenicity in fermented soybean (Kanjang) inoculated with Bacillus sp. SP-KSW3 starter was investigated for the ripening duration of fermentation. Tyrosinase and ACE showed 7% higher activity degree on the Kanjang maturated fermented 2 years with Bacillus sp. SP-KSW3 (Type I) than test field than Kanjang maturated 2 years (control). For antimutagenicity using S. enterica serovar Typhimurium TA100 against MNNG and NPD showed 35.17% and 28.37% (Type I). Similarly, S. enterica serovar Typhimurium TA98 was used against NPD and NQO showed 25.48% and 21.64% (Type I), respectively. Hydrogen donating ability 2 year for maturing (Type I) appeared most highly in the test eulogy 83.1% which it makes. Daidzin of isoflavone in fermented soybean showed similarly. Genistein was not detected The initial test field for daidzin and genistein contained 3.95 mg/kg and 1.25 mg/kg (Type I), respectively.