• Title/Summary/Keyword: Hg-B

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Effects of Collection Methods on Recovery Efficiency, Maturation Rate and Subsequent Embryonic Developmental Competence of Oocytes in Holstein Cow

  • Wang, Zheng-guang;Yu, Song-dong;Xu, Zi-rong
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.4
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    • pp.496-500
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    • 2007
  • Holstein cow ovaries obtained at a slaughterhouse were used to study the influence of the oocyte collection methods (slicing, puncture, aspiration I and II) on recovery efficiency and subsequent in vitro maturation and embryonic development competence of immature oocytes recovered. In the slicing method, the whole ovarian was chopped into small pieces with a surgical blade. In the puncture method, the whole ovarian surface was punctured by 18-g needle. In other 2 aspiration methods, collected oocytes by aspirating from the visible follicles using an 18-g needle attached to a 5 ml syringe (aspiration I) or using a constant negetive pressure (-80 mmHg) with a vacuum pump (aspiration II). The oocytes were classified into 4 classes on the basis of the morphology of cumulus cells and cytoplasmic appearance of oocyte. Slicing ($9.6{\pm}0.4$) and puncture ($9.7{\pm}0.4$)yielded a larger number of oocytes per ovary than other two aspiration methods (aspiration I and II were $5.8{\pm}0.3$and $5.6{\pm}0.4$, respectively) (p<0.05). The number of the highest quality oocytes (grade A) per ovary was significantly higher in slicing ($4.2{\pm}0.2$) and puncture ($4.6{\pm}0.1$) methods than in other methods (aspiration I and II were $1.2{\pm}0.2$ and $1.4{\pm}0.2$, respectively) (p<0.05). The rate of nuclear maturation of the highest and higher quality oocytes (grade A and grade B, respectively) was not affected by the oocytes collection methods. The oocytes collection methods also did not influence subsequent embryonic developmental competence after in vitro fertilization with M II stage oocytes. It is concluded that slicing and puncture methods of the ovaries can be used as an alternative techniques to aspiration by the syringe or vacuum pump.

Cloning, Expression, and Characterization of a Cold-Adapted Lipase Gene from an Antarctic Deep-Sea Psychrotrophic Bacterium, Psychrobacter sp. 7195

  • Zhang, Jinwei;Lin, Shu;Zeng, Runying
    • Journal of Microbiology and Biotechnology
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    • v.17 no.4
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    • pp.604-610
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    • 2007
  • A psychrotrophic strain 7195 showing extracellular lipolytic activity towards tributyrin was isolated from deep-sea sediment of Prydz Bay and identified as a Psychrobacter species. By screening a genomic DNA library of Psychrobacter sp. 7195, an open reading frame of 954 bp coding for a lipase gene, lipA1, was identified, cloned, and sequenced. The deduced LipA1 consisted of 317 amino acids with a molecular mass of 35,210 kDa. It had one consensus motif, G-N-S-M-G (GXSXG), containing the putative active-site serine, which was conserved in other cold-adapted lipolytic enzymes. The recombinant LipA1 was purified by column chromatography with DEAE Sepharose CL-4B, and Sephadex G-75, and preparative polyacrylamide gel electrophoresis, in sequence. The purified enzyme showed highest activity at $30^{\circ}C$, and was unstable at temperatures higher than $30^{\circ}C$, indicating that it was a typical cold-adapted enzyme. The optimal pH for activity was 9.0, and the enzyme was stable between pH 7.0-10.0 after 24h incubation at $4^{\circ}C$. The addition of $Ca^{2+}\;and\;Mg^{2+}$ enhanced the enzyme activity of LipA1, whereas the $Cd^{2+},\;Zn^{2+},\;CO^{2+},\;Fe^{3+},\;Hg^{2+},\;Fe^{2+},\;Rb^{2+}$, and EDTA strongly inhibited the activity. The LipA1 was activated by various detergents, such as Triton X-100, Tween 80, Tween 40, Span 60, Span 40, CHAPS, and SDS, and showed better resistance towards them. Substrate specificity analysis showed that there was a preference for trimyristin and p-nitrophenyl myristate $(C_{14}\;acyl\; groups)$.

${\alpha}$-Galactosidase from Bacillus megaterium VHM1 and Its Application in Removal of Flatulence-Causing Factors from Soymilk

  • Patil, Aravind Goud G.;Kumar S.K., Praveen;Mulimani, Veerappa H.;Veeranagouda, Yaligara;Lee, Kyoung
    • Journal of Microbiology and Biotechnology
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    • v.20 no.11
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    • pp.1546-1554
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    • 2010
  • A bacterial strain capable of producing extracellular ${\alpha}$-galactosidase was isolated from a sample of sugarcane industrial waste. Microbiological, physiological, and biochemical studies revealed that the isolate belonged to Bacillus sp. Furthermore, based on a 16S rDNA sequence analysis, the new isolate was identified as Bacillus megaterium VHM1. The production of ${\alpha}$-galactosidase was optimized based on various physical culture conditions. Guar gum and yeast extract acted as the best carbon and nitrogen sources, respectively. The optimum pH was 7.5 and the enzyme remained stable over a pH range of 5-9. The enzyme was optimally active at $55^{\circ}C$ and thermostable with a half-life of 120 min, yet lost 90% of its residual activity within 120 min at $60^{\circ}C$. One mM concentrations of $Ag^2$, $Cu^2$, and $Hg^{2+}$ strongly inhibited the ${\alpha}$-galactosidase, whereas the metal ions $Fe^2$, $Mn^{2+}$, and $Mg^{2+}$ had no effect on the ${\alpha}$-galactosidase activity, and $Zn^{2+}$, $Ni^{2+}$, and $Ca^{2+}$ reduced the enzyme activity slightly. When treated with the B. megaterium VHM1 enzyme, the flatulence-causing sugars in soymilk were completely hydrolyzed within 1.5 h.

Purification and Characterization of Two Novel Fibrinolytic Proteases from Mushroom, Fomitella fraxinea

  • Lee Jong-Suk;Baik Hyung-Suk;Park Sang-Shin
    • Journal of Microbiology and Biotechnology
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    • v.16 no.2
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    • pp.264-271
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    • 2006
  • Two fibrinolytic enzymes were purified from the culture supernatant of Fomitella fraxinea mycelia by ion-exchange and gel filtration chromatographies, and were designated as F. fraxenia proteases 1 and 2 (FFP1 and FFP2). The apparent molecular masses of the enzymes were estimated to be 32 kDa and 42 kDa, respectively, by SDS-PAGE and gel filtration chromatography. Both enzymes had the same optimal temperature ($40^{\circ}C$), but different pH optima (10.0 and 5.0 for FFP1 and FFP2, respectively). FFP1 was relatively stable at pH 7.0-9.0 and temperature below $30^{\circ}C$, whereas FFP2 was very stable in the pH range of 4-11 and temperature below $40^{\circ}C$. FFPI activity was completely inhibited by phenylmethylsulfonyl fluoride (PMSF) and aprotinin, indicating that this enzyme is a serine protease. The activity of FFP2 was enhanced by the addition of $CO^{2+}$ and $Zn^{2+}$ and inhibited by $Cu^{2+},\;Ni^{2+}$, and $Hg^{2+}$. Furthermore, FFP2 activity was strongly inhibited by EDTA and 1,10-phenanthroline, implying that the enzyme is a metalloprotease. Both enzymes readily hydrolyzed fibrinogen, preferentially digesting the $A{\alpha}$- and $B{\beta}$-chains of fibrinogen over ${\gamma}$-chain. FFP1 showed broad substrate specificity for synthetic substrates, but FFP2 did not. $K_{m}$ and $V_{max}$ values of FFP1 for a synthetic substrate, N-succinyl-Ala-Ala-Pro-Phe-pNA, were 0.213 mM and 39.68 units/ml, respectively. The first 15 amino acids of the N-terminal sequences of both enzymes were APXXPXGPWGPQRIS and ARPP(G)VDGQ(R,I)SK(L)ETLPE, respectively.

Hematological and serum biochemical studies in fresh water fish exposed to acute and chronic copper and mercury toxicity

  • H.A., Sawsan;H.M., Amira;M.B., Mostafa;AM.M., Nashaat
    • Journal of fish pathology
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    • v.30 no.1
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    • pp.25-39
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    • 2017
  • A total number of 668 apparently healthy fish were obtained from farm to study the effect of two heavy metals in a form of (Copper sulfate and Mercuric chloride) on some hematological and biochemical parameters of blood. The $LC_{50}$ /96 hr. of Cu and Hg were estimated and fish exposed to $\text\tiny{^1/_2}$ $LC_{50}$ for 7 days and for $1/_{10}$ $LC_{50}$ for 8 weeks from each product separately. Results showed decrease in RBCs count, PCV% and Hb in acute and chronic mercury while a significant increase was shown in acute and chronic copper toxicity, total leucocytic count showed decrease in acute mercury toxicity and increase in the chronic case, while in copper toxicity non-significant decrease in acute and significant decrease in chronic toxicity was noticed. Elevated serum urea and creatinine in both acute and chronic mercury and copper toxicity was detected. No changes in total bilirubin in the acute mercury and chronic copper toxicity while significant increase in chronic mercury and acute copper. Elevation of serum AST and ALT in some days of acute toxicity of mercury and copper while in chronic mercury toxicity a significant elevation of both serums AST and ALT were detected .while in chronic copper toxicity serum AST was fluctuated and ALT showed no significant changes. CK study revealed significant decrease in acute mercury with fluctuation in the chronic toxicity while in copper toxicity it showed fluctuation in acute and significant decrease in chronic toxicity. Glucose value decreased in acute and chronic mercury toxicity while in copper toxicity it showed significant increase in the acute and increase followed by significant decrease in the chronic copper toxicity.

Soil Characteristics and Management Proposal of the Monument Beobsoo Marsh, Korea (천연기념물 법수늪의 토양특성 및 관리방안)

  • Kim, Do-Gyun;Kim, Yong-Shik
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.3
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    • pp.15-32
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    • 2011
  • This study was carried out to investigate the soil characteristics and propose the management for the Monument Beobsoo Marsh, Korea. The soil properties of O.M, $Ca^{2+}$, $Na^+$ and CEC were higher and the soil properties of pH_{1:5}$ and $P_2O_5$ were lower the studied sites than other marsh sites in Korea. Although the Heavy metals such as Pb, Hg, Cd, Cu, Zn, Cr and As were lower compare to the safety standard of soil pollution in Korea, the overall conservation management plan based on long-term monitoring should be considered just because it varied by the point and non-point source pollution within the studied marsh. The source of water pollution varied due to non-point polluting origins such as sewage inlet, degraded terrain for agriculture, fishing sites, sites of removed water grasses, pesticides, chemical fertilizers, as well as fallen leaves. The creation of an artificial marsh is recommended due to the soil environment of the studied sites may be changed owing to the accumulated contaminants from the sources of both of point or non-point contaminants. The establishment of the zones of core, buffer and transition which is basic management structure of the UNESCO MaB could be applied to manage the studied site. Simultaneously the promotion of voluntary participation and education of the local residents are needed.

The mechanical and antimicrobial properties of chitosan crosslinked rayon fabric - Effect of chitosan and epichlorohydrin(ECH) concentration - (키토산 가교처리된 레이온 직물의 역학적특성과 항균성 - 에피클로로히드린과 키토산 농도의 영향 -)

  • Ahn, Jung-Mi;Kim, Min-Ji;Lee, Shin-Hee
    • Textile Coloration and Finishing
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    • v.18 no.6 s.91
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    • pp.16-24
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    • 2006
  • The purpose of this study is to improve the defects of chitosan crosslinked viscose rayon by ECH and to describe the change of hand of chitosan crosslinked viscose rayon fabrics. The chitosan crosslinked viscose rayon were manufactured by crosslinking process using ECH as crosslinking agent, 2 wt% aqueous acetic acid as a solvent of chitosan and ECH, and 20 wt% aqueous sodium hydroxide as crosslinking catalyst. Viscose rayon were first immersed in the pad bath of the mixed solution of chitosan and ECH, padded up to 100 wt% wet pick-up on weight of fiber(owf), precured on pin frames at $130^{\circ}C$ for 2 minutes, immersed in NaOH solution and finally wash and dry. Antimicrobial properties of the viscose rayon treated with chitosan were measured by the shake flask C.T.M. 0923 test method with staphylococcus aureus(ATCC 6538) as the microorganism. When the concentration of chitosan was increased chitosan crosslinked viscose rayon's LT, WT, B, 2HB and MIU were increased and G, 2HG, SMD, T and $T_m$ were decreased. On the other hand, WT, EM were decreased and RT was increased at $1{\times}10^{-2}M$ ECH. The optimum condition for crosslinking was that ECH concentration was between $1{\times}10^{-2}M\;and\;5{\times}10^{-2}M$. Antimicrobial effects of rayon fabric treated with chitosan was excellent.

Interference Analysis of Radio-Relay Stations Affected by HAPS System for Frequency Sharing (주파수 공유를 위한 HAPS 시스템이 무선 중계국에 미치는 간섭 영향 분석)

  • 박종민;구본준;안도섭;김봉석;강영흥
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.7B
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    • pp.719-726
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    • 2002
  • In WRC-2000, Resolution 734 was adopted to study the use of high altitude platform station(HAPS) operating in the bands above 30GHz. Therefore, frequency sharing feasibility between a new HAPS systems and an existing terrestrial fixed-service(FS) system should be analyzed primarily. In this paper, interference effects from the HAPS system into the radio-relay station are analyzed in terms of two cases; one is the interference distribution from the power-flux density(PFD) of HAPS airships, and the other the interference power from the ground stations. In conclusion, the new PFD criteria different from the exiting satellite system should be required, and the coordinated distance between the HAPS nadir and the radio-relay station should be 60km ∼ 253km for P$\sub$HG/ = -50dBW/MHz of transmitting power spectral density to share the new HAPS system into the existing FS system.

A Novel Metalloprotease from the Wild Basidiomycete Mushroom Lepista nuda

  • Wu, Y.Y.;Wang, H.X.;Ng, T.B.
    • Journal of Microbiology and Biotechnology
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    • v.21 no.3
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    • pp.256-262
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    • 2011
  • A 20.9-kDa metalloprotease was isolated from dried fruiting bodies of the wild basidiomycete mushroom Lepista nuda. The N-terminal amino acid sequence of the protease was seen to be ATFVLTAATNTLFTA, thus displaying no similarity with the sequences of previously reported metalloproteases. The protease was purified using a procedure that entailed ion-exchange chromatography on CM-Cellulose, Q-Sepharose, and Mono S, and FPLC-gel filtration on Superdex 75. The protease functioned at an optimum pH of 7.0 and an optimum temperature of $50^{\circ}C$. It was also noted that the protease demonstrated a proteolytic activity of 1,756 U/mg toward casein. The $K_m$ of the purified protease toward casein was 6.36 mg/ml at a pH of 7.0 and with a temperature of $37^{\circ}C$, whereas the $V_{max}$ was 9.11 ${\mu}g\;ml^{-1}\;min^{-1}$. The activity of the protease was adversely affected by EDTA-2Na, suggesting that it is a metalloprotease. PMSF, EGTA, aprotinin, and leupeptin exerted no striking inhibitory effect. The activity of the protease was enhanced by $Fe^{2+}$, but was curtailed by $Cd^{2+}$, $Cu^{2+}$, $Hg^{2+}$, $Pb^{2+}$, $Zn^{2+}$, and $Fe^{2+}$ ions. The protease also exhibited inhibitory activity against HIV-1 reverse transcriptase with an $IC_{50}$ value of 4.00 ${\mu}M$. The $IC_{50}$ values toward hepatoma Hep G2 and leukemia L1210 cells in vitro were 4.99 ${\mu}M$ and 3.67 ${\mu}M$, respectively.

Cloning, High-Level Expression, Purification, and Properties of a Novel Endo-${\beta}$-1,4-Mannanase from Bacillus subtilis G1 in Pichia pastoris

  • Vu, Thi Thu Hang;Quyen, Dinh Thi;Dao, Thi Tuyet;Nguyen, Sy Le Thanh
    • Journal of Microbiology and Biotechnology
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    • v.22 no.3
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    • pp.331-338
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    • 2012
  • A novel gene coding for an endo-${\beta}$-1,4-mannanase (manA) from Bacillus subtilis strain G1 was cloned and overexpressed in P. pastoris GS115, and the enzyme was purified and characterized. The manA gene consisted of an open reading frame of 1,092 nucleotides, encoding a 364-aa protein, with a predicted molecular mass of 41 kDa. The ${\beta}$-mannanase showed an identity of 90.2-92.9% ${\leq}95%$) with the corresponding amino acid sequences from B. subtilis strains deposited in GenBank. The purified ${\beta}$-mannanase was a monomeric protein on SDS-PAGE with a specific activity of 2,718 U/mg and identified by MALDI-TOF mass spectrometry. The recombinant ${\beta}$-mannanase had an optimum temperature of $45^{\circ}C$ and optimum pH of 6.5. The enzyme was stable at temperatures up to $50^{\circ}C$ (for 8 h) and in the pH range of 5-9. EDTA and most tested metal ions showed a slightly to an obviously inhibitory effect on enzyme activity, whereas metal ions ($Hg^{2+}$, $Pb^{2+}$, and $Co^{2+}$) substantially inhibited the recombinant ${\beta}$-mannanase. The chemical additives including detergents (Triton X-100, Tween 20, and SDS) and organic solvents (methanol, ethanol, n-butanol, and acetone) decreased the enzyme activity, and especially no enzyme activity was observed by addition of SDS at the concentrations of 0.25-1.0% (w/v) or n-butanol at the concentrations of 20-30% (v/v). These results suggested that the ${\beta}$-mannanase expressed in P. pastoris could potentially be used as an additive in the feed for monogastric animals.