• Asian-Australasian Journal of Animal Sciences
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• v.32 no.7
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• pp.977-987
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• 2019

Objective: The use of tannin extract and other phytochemicals as dietary additives in ruminants is becoming more popular due to their wide biological actions such as in methane mitigation, bypass of dietary protein, intestinal nematode control, among other uses. Unfortunately, some have strong astringency, low stability and bioavailability, and negatively affecting dry matter intake and digestibility. To circumvent these drawbacks, an effective delivery system may offer a promising approach to administer these extracts to the site where they are required. The objectives of this study were to encapsulate acacia tannin extract (ATE) with native starch and maltodextrin-gum arabic and to test the effect of encapsulation parameters on encapsulation efficiency, yield and morphology of the microparticles obtained as well as the effect on rumen in vitro gas production. Methods: The ATE was encapsulated with the wall materials, and the morphological features of freeze-dried microparticles were evaluated by scanning electron microscopy. The in vitro release pattern of microparticles in acetate buffer, simulating the rumen, and its effect on in vitro gas production was evaluated. Results: The morphological features revealed that maltodextrin/gum-arabic microparticles were irregular shaped, glossy and smaller, compared with those encapsulated with native starch, which were bigger, and more homogenous. Maltodextrin-gum arabic could be used up to 30% loading concentration compared with starch, which could not hold the core material beyond 15% loading capacity. Encapsulation efficiency ranged from $27.7%{\pm}6.4%$ to $48.8%{\pm}5.5%$ in starch and $56.1%{\pm}4.9%$ to $64.8%{\pm}2.8%$ in maltodextrin-gum arabic microparticles. Only a slight reduction in methane emission was recorded in encapsulated microparticles when compared with the samples containing only wall materials. Conclusion: Both encapsulated products exhibited the burst release pattern under the pH conditions and methane reduction associated with tannin was marginal. This is attributable to small loading percentages and therefore, other wall materials or encapsulation methods should be investigated.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.19-29
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• 1996

The neurological manifestations of AIDS include dementia, encountered even in the absence of opportunistic superinfection or malignancy. The AIDS Dementia Complex appears to be associated with several neuropathological abnormalities, including astrogliosis and neuronal injury or loss. How can HIV-1 result in neuronal damage if neurons themselves are only rarely, if ever, infected by the vitus\ulcorner In vitro experiments from several different laboratiories have lent support to the existence of HIV- and immune-related toxins. In one recently defined pathway to neuronal injury, HIV-infected macrophages/microglia as well as macrophages activated by HIV-1 envelope protein gp120 appear to secrete excitants/neurotoxins. These substances may include arachidonic acid, platelet-activating factor, free radicals (NO - and O$_2$), glutamate, quinolinate, cysteine, cytokines (TNF-${\alpha}$, IL1-B, IL-6), and as yet unidentified factors emanating from stimulated macrophages and possibly reactive astrocytes. A final common pathway for newonal suscepubility appears to be operative, similar to that observed in stroke, trauma, epilepsy, and several neurodegenerative diseases, including Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis. This mechanism involves excessive activation of N-methyl-D-aspartate (NMDA) receptor-operated channels, with resultant excessive influx of Ca$\^$2+/ leading to neuronal damage, and thus offers hope for future pharmacological intervention. This chapter reviews two clinically-tolerated NMDA antagonists, memantine and nitroglycerin; (ⅰ) Memantine is an open-channel blocker of the NMDA-associated ion channel and a close congener of the anti-viral and anti-parkinsonian drug amantadine. Memantine blocks the effects of escalating levels of excitotoxins to a greater degree than lower (piysiological) levels of these excitatory amino acids, thus sparing to some extent normal neuronal function. (ⅱ) Niuoglycerin acts at a redox modulatory site of the NMDA receptor/complex to downregulate its activity. The neuroprotective action of nitroglycerin at this site is mediated by n chemical species related to nitric oxide, but in a higher oxidation state, resulting in transfer of an NO group to a critical cysteine on the NMDA receptor. Because of the clinical safety of these drugs, they have the potential for trials in humans. As the structural basis for redox modulation is further elucidated, it may become possible to design even better redox reactive reagents of chinical value. To this end, redox modulatory sites of NMDA receptors have begun to be characterized at a molecular level using site-directed mutagenesis of recombinant subunits (NMDAR1, NMDAR2A-D). Two types of redox modulation can be distinguished. The first type gives rise to a persistent change in the functional activity of the receptor, and we have identified two cysteine residues on the NMDARI subunit (#744 and #798) that are responsible for this action. A second site, presumably also a cysteine(s) because <1 mM N-ethylmaleimide can block its effect in native neurons, underlies the other, more transient redox action. It appears to be at this, as yet unidentified, site on the NMDA receptor that the NO group acts, at least in recombinant receptors.

• BMB Reports
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• v.40 no.3
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• pp.315-324
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• 2007

The novel $\alpha$-amylase purified from locally isolated strain, Bacillus sp. KR-8104, (KRA) (Enzyme Microb Technol; 2005; 36: 666-671) is active in a wide range of pH. The enzyme maximum activity is at pH 4.0 and it retains 90% of activity at pH 3.5. The irreversible thermoinactivation patterns of KRA and the enzyme activity are not changed in the presence and absence of $Ca^{2+}$ and EDTA. Therefore, KRA acts as a $Ca^{2+}$-independent enzyme. Based on circular dichroism (CD) data from thermal unfolding of the enzyme recorded at 222 nm, addition of $Ca^{2+}$ and EDTA similar to its irreversible thermoinactivation, does not influence the thermal denaturation of the enzyme and its Tm. The amino acid sequence of KRA was obtained from the nucleotide sequencing of PCR products of encoding gene. The deduced amino acid sequence of the enzyme revealed a very high sequence homology to Bacillus amyloliquefaciens (BAA) (85% identity, 90% similarity) and Bacillus licheniformis $\alpha$-amylases (BLA) (81% identity, 88% similarity). To elucidate and understand these characteristics of the $\alpha$-amylase, a model of 3D structure of KRA was constructed using the crystal structure of the mutant of BLA as the platform and refined with a molecular dynamics (MD) simulation program. Interestingly enough, there is only one amino acid substitution for KRA in comparison with BLA and BAA in the region involved in the calcium-binding sites. On the other hand, there are many amino acid differences between BLA and KRA at the interface of A and B domains and around the metal triad and active site area. These alterations could have a role in stabilizing the native structure of the loop in the active site cleft and maintenance and stabilization of the putative metal triad-binding site. The amino acid differences at the active site cleft and around the catalytic residues might affect their pKa values and consequently shift its pH profile. In addition, the intrinsic fluorescence intensity of the enzyme at 350 nm does not show considerable change at pH 3.5-7.0.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.293-308
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• 2014

This study was carried out to investigate the vascular plants in the construction site of the National DMZ Native Botanic Garden. The period of survey was from May 2012 to November 2013. Vascular plants based on voucher specimen were summarized as 313 taxa including 79 families, 211 genera, 272 species, 4 subspecies, 32 varieties, 4 forms and 1 hybrids. The rare plant species designated by Korea Forest Service were 8 taxa including Galium boreale L., Eleutherococcus senticosus (Rupr. & Maxim.) Maxim., Eranthis stellata Maxim. and Lloydia triflora (Ledeb.) Baker, etc. Endemic plant species were 4 taxa including Salix koriyanagi Kimura, Clematis trichotoma Nakai, Philadelphus schrenkii Rupr. and Cirsium setidens (Dunn) Nakai. Furthermore, 51 taxa were listed as specific plant species based on phytogeographical in the investigated area. The naturalized plants were recorded as 11 taxa, and their Naturalization Ratio and Urbanization Index were recorded as 3.51%, and 3.43%, respectively.

• Korean Journal of Plant Resources
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• v.8 no.2
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• pp.165-173
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• 1995

This study was conducted to clarify not only the phytogeographical distribution but also species characteristics of Korean-native Anacardiaceae. 6 species of I genus were ascertained from herbarium specimens and field survey of natural population. Rhus verniciflua have been mainly cultivated in Wonju region, Kangwon-do and Hamyang region, Kyeongsangnam-do, could be cultivated in all parts of Korea, especially more in cold area. R. trichocarpa was distributed in all parts except for some far-islands of South in Korea. Petiole was especially reddish. Fruits are matured in June-July, and have stiff trichomes. R. sylvestris was widely distributed in the subtropical-temperate and temperate zone, and mainly distributed in the seashore and islands under 36$^{\circ}$ in Korea. Leaflets and petiole was reddish, and fruits were glabrous. R succedanea was only distributed in Jeju-do and several islands which is subtropical zone in Korea. Leaflets were lanceolate to oblong, characterized by little trichomes. R.chinensis is a ubiquitous tree which is widely distributed in the temperate zone, in Korea, and ranged perpendicularly to 800-900m. Inflorescense was characterized by apical site. Fruit was covered with dense short hairs and sometimes milky latex. R. ambigua was only distributed in subtropical zone, native in Kwang-do and Sangbaek-do, Yeochon-gun, Chunlanam-do in Korea. Especially, this species was a vine, trifoliolate and most poisonous. Leaflets were coriaceous, glabrous, and revolute type.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.1
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• pp.126-133
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• 2016

A gene from Actinomyces sp. Korean native goat (KNG) 40 that encodes an endo-${\beta}$-1,4-glucanase, EG1, was cloned and expressed in Escherichia coli (E. coli) $DH5{\alpha}$. Recombinant plasmid DNA from a positive clone with a 3.2 kb insert hydrolyzing carboxyl methyl-cellulose (CMC) was designated as pDS3. The entire nucleotide sequence was determined, and an open-reading frame (ORF) was deduced. The ORF encodes a polypeptide of 684 amino acids. The recombinant EG1 produced in E. coli $DH5{\alpha}$ harboring pDS3 was purified in one step using affinity chromatography on crystalline cellulose and characterized. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis/zymogram analysis of the purified enzyme revealed two protein bands of 57.1 and 54.1 kDa. The amino terminal sequences of these two bands matched those of the deduced ones, starting from residue 166 and 208, respectively. Putative signal sequences, a Shine.Dalgarno-type ribosomal binding site, and promoter sequences related to the consensus sequences were deduced. EG1 has a typical tripartite structure of cellulase, a catalytic domain, a serine-rich linker region, and a cellulose-binding domain. The optimal temperature for the activity of the purified enzyme was $55^{\circ}C$, but it retained over 90% of maximum activity in a broad temperature range ($40^{\circ}C$ to $60^{\circ}C$). The optimal pH for the enzyme activity was 6.0. Kinetic parameters, $K_m$ and $V_{max}$ of rEG1 were 0.39% CMC and 143 U/mg, respectively.

• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.285-293
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• 2009

This research had been executed to find out the structure of Magnolia obovata community, a dispersal range and characteristics of scatter investigation, and to prepare management measure of it. In the result of this study, Magnolia obovata was distributed in a native plant community from planting trees of UNESCO Peace Center. The maximum numbers of Magnolia obovata were found in $20{\sim}100m$ from trees of mother. Seed of Magnolia obovata has a characteristics of gravity dispersal. But some individuals was found in 420m from its tree of mother. Seeds of Magnolia obovata has a characteristics of animal dispersal, too. Major species of animal dispersal are Garrulus glandarius, Ciurus vulgaris coreae, and Tamias sibiricus asiaticus in the study site. The importance value between native plants and Magnolia obovata had a negative relation. Because Magnolia obovata is more shade tolerant than other trees. Also, the growth of Magnolia obovata is faster than other trees. And so if the influence of Magnolia obovata reduce, it is necessary to expand native plant community, and to cut Magnolia obovata over 10m of the height and over 10cm of the DBH, for preventing influence of Magnolia obovata.

• Journal of Microbiology
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• v.42 no.4
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• pp.340-345
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• 2004

To investigate the co-expression and crystallization of a fusion gene between the Bacillus thuringiensis crystal protein and a foreign protein in B. thuringiensis, the expression of the Cry1Ac fused with green fluorescent protein (GFP) genes in a B. thuringiensis $Cry^-B$ strain was examined. The cry1Ac gene was cloned in the B. thuringiensis-E. coli shuttle vector, pHT3101, under the control of the native cry1Ac gene promoter, while the GFP gene was inserted into the XhoI site upstream of the proteolytic cleavage site, in the middle region of the crylAc gene (pProAc-GFP). The B. thuringiensis $Cry^-B$ strain carrying pProAc-GFP (ProAc-GFP/CB) did not produce any inclusion bodies. However, the transformed strain expressed fusion protein forms although the expression level was relatively low. Furthermore, an immu­noblot analysis using GFP and Cry1Ac antibodies showed that the fusion protein was not a single spe­cies, but rather multiple forms. In addition, the N-terminal fragment of Cry1Ac and a non-fused GFP were also found in the B. thuringiensis $Cry^-B$ strain after autolysis. The sporulated cells before autolysis and the spore-crystal mixture after autolysis of ProAc-GFP/CB exhibited insecticidal activities against Plutella xylostella larvae. Accordingly, the current results suggest that a fusion crystal protein produced by the transfomant, ProAc-GFP/CB, can be functionally expressed but easily degraded in B. thuring­iensis.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.5
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• pp.65-77
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• 2014

The ecosystem of Jaemin stream, flowing into the center of Gongju-si, had been damaged by low water quality and lack of water quantity of the steam. However, after applying the SSB (Sustainable Structured wetland Biotop) system to the flood plain and the upstream of Jaemin stream, the efficiency of ecological water purification and ecological restoration are as follows. Through the constant maintenance and monitoring from year 2009 to year 2013 after restorative design and construction the average influent concentration of BOD5 was 4.2 mg/L, and the average effluent concentration was 1.8 mg/L, reaching ecological water purification rate of 57%. As for the T-N, the average influent concentration was 9.983 mg/L, and the average effluent concentration was 6.303 mg/L, showing the rate of 37%. For the T-P, the average influent concentration was 0.198 mg/L, and the average effluent concentration was 0.098 mg/L, being the rate of 51%. The vegetation of Jaemin stream monitored for 2 years after the restoration was composed of 51 species in 28 families which show high ratio of planted native species. As for the animals in the site, 5 species in 3 families of reptiles and amphibians, 34 species of 23 families of birds, and 3 species in 2 families of mammals were monitored, indicating that the bio-diversity of the site has improved, as well.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.13-16
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• 2005

This study was performed to detect genetic variation of the heart fatty acid-binding protein (H-FABP) gene by PCRRFLPs approach and its association with intramuscular fat (IMF) content. Data from 223 individuals, including one Chinese native pig breed and four western pig breeds, were analyzed. The results showed that for the H-FABP gene, there was one polymorphic HinfI site in the 5'-upstream region, whereas there were one HaeIII and one HinfI (marked as $HinfI^*$) polymorphic site in the second intron, respectively. The three PCR-RFLPs were present in all breeds tested. The allele frequencies, however, revealed significant differences between them (p<0.05). Furthermore, the allele frequency distribution of HinfI in the Laiwu Black and that of $HinfI^*$ in the Hampshire breed were at disequilibrium, which might be the result of selective breeding. Results also indicated that for HinfI, HaeIII and $HinfI^*$ HFABP RFLP, significant (p<0.05) contrasts of 0.78%, -0.69% and 0.72% were detected in the least square means of IMF content between the homozygous genotype HH and hh, DD and dd, BB and bb classes, respectively. It implied that the HHddBB genotype had the highest IMF content in this experimental population and these H-FABP RFLPs could serve, to some extent, as genetic markers for use in improvement of IMF content.