• Journal of the Korean Wood Science and Technology
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• 제10권2호
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• pp.12-21
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• 1982

Red pine and Japanese larch (Larix leptolepis Gordon) grown in Korea have been the main species of coniferous resources in Korea. Especially, planting area of Japanese larch has been increased continueously in the recent years due to its superior plant type and rapid growth rate and its stocks reached approximately 4.32 million cubic meters at the present time. Although many research works have been done for the utilization of the larch wood in various ways, still many problems are existed in its chemical applications due to a large proportion of soluble extractives. In this study, chemical composition of larch extractives and chemical structure of its major component were analyzed. In order to identify the basic structure of major component, gas-liquid chromatography for separation of some completely methylated alditols as their acetates on a 3% - ECNSS-M on Gas Chrom Q. column was used. Proportion of extractives of Japanese larch wood was higher than that of other conifers and major component of the soluble extractives was arabinogalactan, a schematic structural formula which was presented in Figure 2. The molar ratio of arabinose and galactose was 1:4.5. The main chain of arabinogalactan was composed of 1,3 linked ${\beta}$-D-galactopyranose residues, each of which carried a side chain, attached to the C-6 positions. The exact nature of all of the side chains is not known, but the majority of these side chain was composed of 1, 6 linked ${\beta}$-D-galactopyranose residues, with 2~3 such units present per average chain. Some of the galactose units in the main chain had a residue of 3 - 0 - ${\beta}$-L-arabinopyranosyl-L-arabinofuranose. In addition, a few terminal residues of D-glucuronic acid also was confirmed, attached to C-6 position of the D-galactopyranose residue. It could concluded that the main structure of highly branched arabinogalactan from Japanese larch extractive was essentially the same as those of the other larch species.

• Asian-Australasian Journal of Animal Sciences
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• 제28권9호
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• pp.1362-1370
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• 2015

This study was performed to investigate the effect of different levels of dietary crude protein (CP) on composition of odorous compounds and bacterial communities in pig manure. A total of 48 male pigs (average initial body weight 45 kg) fed diets containing three levels of dietary CP (20%, 17.5%, and 15%) and their slurry samples were collected from the pits under the floor every week for one month. Changes in composition of odorous compounds and bacterial communities were analyzed by gas chromatography and 454 FLX titanium pyrosequencing systems, respectively. Levels of phenols, indoles, short chain fatty acid and branched chain fatty acid were lowest (p<0.05) in CP 15% group among three CP levels. Relative abundance of Bacteroidetes phylum and bacterial genera including Leuconostoc, Bacillus, Atopostipes, Peptonphilus, Ruminococcaceae_uc, Bacteroides, and Pseudomonas was lower (p<0.05) in CP 15% than in CP 20% group. There was a positive correlation (p<0.05) between odorous compounds and bacterial genera: phenol, indole, iso-butyric acid, and iso-valeric acid with Atopostipes, p-cresol and skatole with Bacteroides, acetic acid and butyric acid with AM982595_g of Porphyromonadaceae family, and propionic acid with Tissierella. Taken together, administration of 15% CP showed less production of odorous compounds than 20% CP group and this result might be associated with the changes in bacterial communities especially whose roles in protein metabolism.

• Journal of Animal Science and Technology
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• 제64권4호
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• pp.671-695
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• 2022

The gastrointestinal tract is a complex ecosystem that contains a large number of microorganisms with different metabolic capacities. Modulation of the gut microbiome can improve the growth and promote health in pigs. Crosstalk between the host, diet, and the gut microbiome can influence the health of the host, potentially through the production of several metabolites with various functions. Short-chain and branched-chain fatty acids, secondary bile acids, polyamines, indoles, and phenolic compounds are metabolites produced by the gut microbiome. The gut microbiome can also produce neurotransmitters (such as γ-aminobutyric acid, catecholamines, and serotonin), their precursors, and vitamins. Several studies in pigs have demonstrated the importance of the gut microbiome and its metabolites in improving growth performance and feed efficiency, alleviating stress, and providing protection from pathogens. The use of probiotics is one of the strategies employed to target the gut microbiome of pigs. Promising results have been published on the use of probiotics in optimizing pig production. This review focuses on the role of gut microbiome-derived metabolites in the performance of pigs and the effects of probiotics on altering the levels of these metabolites.

• 한국식품영양학회:학술대회논문집
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• 한국식품영양학회 2001년도 동계 학술심포지움
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• pp.121-121
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• 2001

최소 배지에 여러 아미노산과 대사 산물을 첨가하여 배양시킨 Serratia marcescens ATCC 25419 세포추출물에서여 biodegradative threonine dehydratase (BDTD), biosynthetic threonine dehydratase (BSTD)와 acetolactate syntase (ALS)의 비활성도를 조사하였다. S. marcescens BDTD와 ALS는 낮은 농도 (0.5-2 mM)의 cAMP에 의해 촉진적 조절을 받으며, 비교적 낮은 농도의 isoleucine (1-4 mM)에 의해서는 S. marcescens BSTD의 생합성이 증가되고 높은 농도의 isoleucine (10-30 mM)에서는 감소되고 비교적 낮은 농도의 valine (2-4 mM)에 의해서 S. marcescens ALS의 생합성이 증가되는 것으로 보아 S. marcescens ATCC 25419에서 branched chain 아미노산 생합성 과정의 조절 양상은 Escherichia coli K-12와는 달리, isoleucine의 생합성 과정은 BSTD에 의해 조절되고, valine의 생합성 과정은 ALS에 의해 조절되는 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제16권6호
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• pp.961-964
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• 2006

GDP-mannosyltransferase (GMT) is an enzyme responsible for the addition of a mannose to glucose ($\alpha$[1$\rightarrow$3]) during biosynthesis of the water-soluble branched polysaccharide acetan in Acefobacter species. In an effort to obtain a cellulose-overproducing bacterium, a mutant defective in GMT of Acetobacter xylinum KCCM 10100 was constructed by single crossover homologous recombination using part of the aceA gene encoding GMT amplified by polymerase chain reaction. The GMT-disrupted mutant produced 23% more cellulose, but 16% less water-soluble polysaccharide than those of the wild-type strain. Analysis of the sugar composition by gel permeation chromatography revealed that water-soluble polysaccharides produced by the GMT-defective mutant contained no mannose molecule.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.241.3-242
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• 2003

By acting on vanilloid receptor(VR1). capsaicin excites and then desensitizes a subset of primary neurons involved in nociception, neurogenic inflammation, and a variety of local regulatory functions. Due to this unique biological activity, VR1 is at present one of the most attractive targets for the treatment of pain. However, despite the concentrated effort on agonists, they have been exposed to the side effects such as pungency and/or hypothermia responses. (omitted)

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2391-2396
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• 2011

Benzonaphthofurandiones containing four coplanar fused aromatic rings were synthesized and evaluated for their cytotoxicity against five human cancer cell lines, and their inhibitory activity on topoisomerases. These benzonaphthofurandiones were prepared by condensation of 2,3-dichloronaphthoquinone and three aromatic diols with base catalysts in alcohol. The synthesized compounds were o-alkylated with six dialkylaminoalkyl halides. The hydroxy derivatives (8a-8g) exhibited relatively potent cytotoxicity among the prepared compounds. These compounds were evaluated as excellent inhibitors against topoisomerase II (topo II). Especially, the hydroxy analogue with branched methyl side chain (8e) showed high cytotoxicity against cancer cell lines and good inhibitory activity on topo II.

• Tribology and Lubricants
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• 제25권3호
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• pp.176-181
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• 2009

Aminated polyacrylonitrile as the new organic disperse phases of the anhydrous ER fluid has been synthesized and ER effect of the suspension composed of aminated polyacrylonitrile in silicone oil investigated. The suspension showed a typical ER response (Bingham flow behavior) upon application of an electric field. The shear stress for the suspension exhibited the dependence with a factor equals to 1.6 power on theelectric field. The current density and the conductivity of the of aminated polyacrylonitrile suspension increase with the electric field intensity and moreover the conductivity of the suspension is about 8 order of magnitude higher than that of the silicone oil. On the basis of the the results, aminated polyacrylonitrile suspension showed the ER flow behavior upon application of the electric field due to the polarizability of the branched amine polar group of the aminated polyacrylonitrile particles.

• 한국정밀공학회지
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• 제25권4호
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• pp.118-126
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• 2008

A new approach to the critical speed calculation of general multi-mesh gear chain system included bevel gear is presented. A transfer matrix mode! based on Hibner's branch method is developed and the natural properties of the branched rotor system are calculated with using the ${\lambda}$-matrix formulation. A Campbell diagram, in which the excitation sources caused by the mass unbalance of the rotors, misalignment and the transmitted errors of the gearing are considered, shows that, at the neighborhood of the operating speed, there are the two critical speeds amplifying the first mode and the eighth mode.

• 대한유전성대사질환학회지
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• 제2권1호
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• pp.85-88
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• 2002

저자들은 생후 47일경부터 구토와 산증이 지속되어 시행한 소변 유기산 분석에서 진단된 메칠말로닌산혈증 환아에서 생체 부분 간이식을 시행한 1례에 대해서 문헌 고찰과 함께 보고하는 바이다.