• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.344-349
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• 2004

A gene encoding inulin-degrading enzyme of Bacillus sp. snu-7 with ORF of 1536 nucleotides was cloned. And it was overexpressed as His-tagged protein in E. coli BL21(DE3) pLysS using pRSET B vector containing mature enzyme sequence. Maximum enzyme production was achieved by IPTG (0.1 mM) induction at $OD_{600}$ 1.2 and $30^{\circ}C$ followed by 6 h incubation. The expressed protein purified through immobilized metal affinity chromatography showed molecular mass of 60 kDa on SDS-PAGE. Results of thin-layer chromatography using inulin as a substrate showed the enzyme to be an exotype inulinase capable of producing only monomeric fructose as a product. $K_m$ and $k_{cat}$, for the hydrolyses of inulin and sucrose were $2.28\pm0.08$ mM and 358.05$\pm$20.38 $min^{-l}$, and 22.02$\pm$0.41 mM and 4619.11$\pm$215.12 $$min^{-1}, respectively. Optimal activity of the exoinulinase occurred at pH 7.0 and $50^{\circ}C$.

• Journal of Ecology and Environment
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• v.43 no.1
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• pp.61-72
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• 2019

Background: Organic carbon stored in coastal wetlands, which comprises the major part of oceanic "blue carbon," is a subject of growing interest and concern. In this study, organic carbon storage in coastal wetlands and its economic value were estimated using the raw data of 25 studies related to soil carbon storage. Data were collected from three tidal flats (one protected and two developed areas) and two estuarine salt marshes (one protected and one restored area). Bulk density, soil organic matter content, and standing biomass of vegetation were all considered, with Monte Carlo simulation applied to estimate the uncertainty. Results: Mean carbon storage in two salt marshes ranged between 14.6 and $25.5kg\;C\;m^{-2}$. Mean carbon storage in tidal flats ranged from 18.2 to $28.6kg\;C\;m^{-2}$, with variability possibly related to soil texture. The economic value of stored carbon was estimated by comparison with the price of carbon in the emission trading market. The value of US $ $6600\;ha^{-1}$ is ~ 45% of previously estimated ecosystem services from fishery production and water purification functions in coastal areas. Conclusions: Although our study sites do not cover all types of large marine ecosystem, this study highlights the substantial contribution of coastal wetlands as carbon sinks and the importance of conserving these habitats to maximize their ecosystem services.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1780-1785
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• 2005

Very low density lipoprotein (VLDL) of commercial broiler (CB) and crossbred village chicken (AK) was purified using Fast Protein Liquid Chromatography (FPLC). The fraction collected was then confirmed as VLDL using 4% polyacrylamide gel electrophoresis and transmission electron microscopy (TEM). The particle size of VLDL is 46.8${\pm}$8.6 nm. The VLDL fraction was then subfractionated and the apolipoprotein (apo) profile was studied by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDSPAGE). The CB and AK have almost similar types of apo in both subfractions 1 and 2. The AK showed the presence of apoAI, AIV, D and E whereas the CB had apo AIV, D, E and H. The apo AIV and apo E were present in both subfractions of AK and CB.

• Journal of Microbiology and Biotechnology
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• v.16 no.1
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• pp.57-63
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• 2006

We have cloned a xylanase gene (xynA) from Streptomyces thermocyaneoviolaceus. The deduced amino acid sequences of the XynA, including the active site sequences of glycosyl hydrolase family 10, showed high sequence homology with several xylanases assigned in this category. The XynA was overexpressed under an IPTG inducible T7 promoter control in E. coli BLR(DE3). The overproduced enzymes were excreted into culture supernatants and periplasmic space. The purified XynA had an apparent molecular mass of near 54 kDa, which corresponds to the molecular mass calculated from its gene. The optimum pH and temperature of the purified XynA were determined to be 5.0 and $65^{\circ}C$, respectively. The XynA retained over $90\%$ its activity after the heat treatment at $65^{\circ}C$ for 30 min. The XynA was highly efficient in producing xylose (X1), xylobiose (X2), xylotriose (X3), and xylotetraose (X4) from xylan.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.695-701
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• 1995

An alkaline lipase producing bacteria was isolated from soil and identified as Serratia liquefaciens AL-11. from the results of analysis of its morphological, biochemical and physiological properties. This strain showed the highest productivity of alkaline lipase when grown at pH 9.0 and 30$\circ$C for 42 hours in the medium of 1% peptone, 0.5% tryptone, 0.9% yeast extract, 1% starch, 1% tween 80, 0.05% CaCl$_{2}$ and 0.05% NaCl. The enzyme was purified by ammonium sulfate treatment, Sephadex G-100 gel filtration and DEAE-Sephadex A-50 column chromatography. The specific activity of the purified enzyme was 27 unit/mg protein and the yield of enzyme activity was 61.3%. The homogeneity of the purified enzyme was verified by polyacrylamide gel disc electrophoresis. Molecular weight of the purified enzyme was estimated about 53,000 by sodium dodecyl sulfate- polyacrylamide gel electrophoresis. This enzyme is composed of 17 amino acids of which glycine, proline and glutamic acid were three miajor acids.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.2
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• pp.115-120
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• 1990

Extracellular nuclease(s) in buffalo rumen fluid were purified from strained rumen fluid by a procedure involving Seitz filtration, acetone fractionation and gel filtration on Sephadex G-100. The enzyme resolved into two peaks exhibiting both DNase and RNase activities. The molecular weight of enzyme corresponding to peaks I and II were approximately 30,000 and 12,000 respectively. The properties of enzymes from the two peaks, however, were same. Optimum temperature for both DNase and RNase activities was at $50^{\circ}C$. Whereas DNase activity was stable upto $60^{\circ}C$, RNase activity was stable only up to $50^{\circ}C$. DNase activity recorded two pH optima, one at pH 5.5 and the other at pH 7.0. RNase activity recorded a broad pH optimum between pH 6.0-8.0. pH stability of the enzyme coincided with pH optima for both the activities. DNase activity was stimulated by $Mg^{2+}$ and $Mn^{2+}$ and inhibited by $Fe^{2+}$, $Zn^{2+}$, $Hg^{2+}$ and $Ag^+$. RNase activity was also stimulated by $Mg^{2+}$ and $Mn^{2+}$ and inhibited by $Cu^{2+}$, $Fe^{2+}$, $Zn^{2+}$, $Hg^{2+}$ and $Ag^+$. Reducing agents stimulated both the activities.

• Applied Chemistry for Engineering
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• v.33 no.2
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• pp.133-144
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• 2022

Fast-paced industrial and agricultural development generates large quantities of hazardous heavy metals (HMs), which are extremely damaging to individuals and the environment. Research in both academia and industry has been spurred by the need for HMs to be removed from water bodies. Advanced materials are being developed to replace existing water purification technologies or to introduce cutting-edge solutions that solve challenges such as cost efficacy, easy production, diverse metal removal, and regenerability. Water treatment industries are increasingly interested in activated carbon because of its high adsorption capacity for HMs adsorption. Furthermore, because of its huge surface area, abundant functional groups on surface, and optimal pore diameter, the modified activated carbon has the potential to be used as an efficient adsorbent. Metal-organic frameworks (MOFs), a novel organic-inorganic hybrid porous materials, sparked an interest in the elimination of HMs via adsorption. This is due to the their highly porous nature, large surface area, abundance of exposed adsorptive sites, and post-synthetic modification (PSM) ability. This review introduces PSM methods for MOFs, chemical modification of activated carbons (ACs), and current advancements in the elimination of Pb²⁺, Hg²⁺, and Cd²⁺ ions from water using modified MOFs and ACs via adsorption.

• Korean Journal Plant Pathology
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• v.14 no.1
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• pp.68-73
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• 1998

Barley mild mosaic virus (BaMMV-Kor) was isolated from the southern part of Korea, and by mechanical inoculation onto barley cultivars, purification and production of antibody. BaMMV-Kor purified form infected plants were filamentous particle, with 13 nm in diameter and 250∼300 nm and 500∼650 nm in length. Antibody of BaMMV-Kor was made by injecting the purified virus to the muscle of a rabbit. In gel-diffusion test, antibody to BaMMV-Kor created spur with BaMMV-Kal and BaMMV-M, but did not make spur with BaMMV-Kor infected New Golden, Ishukushirazu, Joshushiro Hadaka and Misato Golden, but did not infect Kashimamugi, Chikurin Ibaraki 1 and Mokusekko 3. In Korean barley cultivars, BaMMV-Kor infected most of the covered barley cultivars, but did not infect Saeolbori. It also infected naked barley cultivars except Chalbori and Hinssalbori. And all the beer barley cultivars were infected by BaMMV-Kor. BaMMV-Kor had two RNAs, RNA 1 (7.5 Kb) and RNA 2 (3.5 Kb), and coat protein (33 KDa).

• Food Science and Biotechnology
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• v.14 no.5
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• pp.621-627
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• 2005

Halitosis is mainly caused by the presence of volatile sulfur-containing compounds (VSC's) produced by proteolytic periodontopathic bacteria in the oral cavity. Various mouth-rinses have been offered on the market as solutions to reduce halitosis. The aim of this study was to find a potent substance for the prevention of halitosis. The halitosis prevention substance (HPS) from cumin seed powder was purified by solvent extraction, silica gel column chromatography and preparative TLC to yield an oil phase (0.98%). Instrumental analysis such as FT-IR, $^1H$-NMR and $^{13}C$-NMR showed that HPS contained an -OH group, -HC=CH-, -COO-, and long chain acyl group. HPS was therefore determined to be 2-hydroxyethyl-${\beta}$-undecenate. HPS inhibited the growth of Fusobacterium nucleatum and Porphyromonas gingivalis, by 72.44% and 64.37% at $1{\times}10^{-2}\;M$, and by 99.85% and 91.62% at $5\;{\times}\;10^{-2}\;M$, respectively. It also inhibited the activity of L-methionine-${\alpha}$-deamino-${\gamma}$-mercaptomethane-lyase (METase), which was produced by oral microbes. Furthermore, the VSC production by oral microbes in the human mouth air decreased with increasing HPS concentration. These results suggested that HPS from cumin seed is an efficient halitosis prevention agent.

• Membrane and Water Treatment
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• v.2 no.4
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• pp.207-223
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• 2011

Supported Liquid Membranes (SLMs) have been widely studied as feasible alternative to traditional processes for separation and purification of various chemicals both from aqueous and organic matrices. This technique offers various advantages like active transport, possibility to use expensive extractants, high selectivity, low energy requirements and minimization of chemical additives. SLMs are not yet used at large scale in industrial applications, because of the low stability. In the present paper, after a brief overview of the state of the art of SLM technology the facilitated transport mechanisms of SLM based separation is described, also introducing the small and the big carrousel models, which are employed for transport modeling. The main operating parameters (selectivity, flux and permeability) are introduced. The problems related to system stabilization are also discussed, giving particular attention to the influence of membrane materials (solid membrane support and organic liquid membrane (LM) phase). Various approaches proposed in literature to enhance SLM stability are also reviewed. Modification of the solid membrane support, creating an additional layer on membrane surface, which acts as a barrier to LM phase loss, increases system stability, but the membrane permeability, and then the flux, decrease. Stagnant Sandwich Liquid Membrane (SSwLM), an implementation of the SLM system, results in both high flux and stability compared to SLM. Finally, possible large scale applications of SLMs are also reviewed, evidencing that if the LM separation process is opportunely carried out (no production of byproducts), it can be considered as a green process.