• Journal of Microbiology and Biotechnology
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• 제13권1호
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• pp.43-49
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• 2003

Metabolism of a new fungicide ethaboxam by soil fungi was studied. Among the fungi tested, Cunninghamelia elegans produced metabolites from ethaboxam, which were not found in the control experiments. M5, a major metabolite from ethaboxam was firmly identified as N-deethylated ethaboxam by LC/MS/MS and NMR. N-Deethylated ethaboxam has been found as a single metabolite in in vitro metabolism with rat liver microsomes. Ml was proved to be 4-ethyl-2-(ethylamino)-1,3-thiazole-5-carboxamide (ETC) by comparing with the authentic compound. In addition, M2, M3, and M4, and M6 were tentatively Identified by LC/MS/MS as hydroxylated and methoxylated ethaboxams, respectively. Production of the major metabolite, N-deethylated ethaboxam, by the fungus suggested that C. elegans would be an efficient eukaryotic microbial candidate for evaluating xenobiotic-driven mammalian risk assessment.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.672-680
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• 2015

As a global regulatory gene in Streptomyces, afsR can activate the biosynthesis of many secondary metabolites. The effect of afsR on the biosynthesis of a phenazine metabolite, lomofungin, was studied in Streptomyces lomondensis S015. There was a 2.5-fold increase of lomofungin production in the afsR-overexpressing strain of S. lomondensis S015 N1 compared with the wild-type strain. Meanwhile, the transcription levels of afsR and two important genes involved in the biosynthesis of lomofungin (i.e., phzC and phzE) were significantly upregulated in S. lomondensis S015 N1. The optimization of metal chlorides was investigated to further increase the production of lomofungin in the afsR-overexpressing strain. The addition of different metal chlorides to S. lomondensis S015 N1 cultivations showed that CaCl₂, FeCl₂, and MnCl₂ led to an increase in lomofungin biosynthesis. The optimum concentrations of these metal chlorides were obtained using response surface methodology. CaCl₂ (0.04 mM), FeCl₂ (0.33 mM), and MnCl₂ (0.38 mM) gave a maximum lomofungin production titer of 318.0 ± 10.7 mg/l, which was a 4.1-fold increase compared with that of S. lomondensis S015 N1 without the addition of a metal chloride. This work demonstrates that the biosynthesis of phenazine metabolites can be induced by afsR. The results also indicate that metal chlorides addition might be a simple and useful strategy for improving the production of other phenazine metabolites in Streptomyces.

• Applied Biological Chemistry
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• 제49권4호
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• pp.339-342
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• 2006

칸나의 뿌리를 80% MeOH용액으로 추출하고, 얻어진 추출물을 EtOAc, n-BuOH 및 물로 용매 분획 하였다. 이 중 EtOAc 분획과 n-BuOH 분획으로부터 silica gel과 octadecyl silica gel(ODS) column chromatography로 정제하여 4종의 화합물을 분리하였다. 각 화합물의 화학구조는 NHR, MS 및 IR 등의 스펙트럼 데이터를 해석하여, $\beta$-sitosterol(1), linoleic aicd methyl ester(2), monoglycosyldiglyceride(3), daucosterol(4)으로 동정하였다. 이 화합물들은 칸나에서 처음으로 분리되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1221-1227
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• 2001

Young lambs (Suffolk wethers, n=18), which were 22 to 26 kg average BW, were chronically exposed to temperatures of +1 to +$4^{\circ}C$ (cold) or +21 to +$24^{\circ}C$ (warm) during 10 wk experimental periods. The sheep were closely shorn and were housed in individual metabolism crates in controlled environment rooms. Sheep consumed pelleted diets ad libitum, which consisted of mainly barley grain and brome grass, and contained 7, 11, or 14% CP. The experimental design consisted of a $2{\times}3$ factorial with a single crossover of environment treatment. Feed intake, BW, feces, and urine excretion were measured. Apparent digestibilities were not affected by diet CP concentration or temperature treatments; however, voluntary intake per kg BW was increased (p<0.05) by diet CP content in both environments. Growing lambs gained weight slightly faster in a cold environment when N intake was above 27 g/d. Nitrogen excretion and N balance were positively related (p<0.01) with diet CP content, and fecal N excretion was significantly increased (p<0.05) in the cold environment. Therefore, dietary CP content strongly influenced N metabolism; however, cold exposure did alter only fecal N excretion. The higher DM intake per kg BW at 11% CP diet in the cold environment permitted ADG comparable to 14% CP diet in the warm environment. The results of this study do support the hypothesis that lambs are better able to utilize a moderate reduction in the CP content of the diet in a cold environment.

• 환경생물
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• 제27권3호
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• pp.279-284
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• 2009

In order to understand food sources-metabolism for the pacific oyster (Crassostrea gigas), the stable isotope ratios of carbon (${\delta}^{13}C$) and nitrogen (${\delta}^{15}N$) of its gut, gill, and muscle as well as potential food sources (particulate organic matter, sedimentary organic matter, benthic microalgae, seagrass detritus) were determined in Dongdae Bay. Average ${\delta}^{13}C$ and ${\delta}^{15}N$ values reflect that oysters primarily fed on sedimentary organic matter as opposed to suspended organic matter during summer and winter seasons. However, the relatively enriched $^{15}N$ values of particulate organic matter (>$250{\mu}m$) and sedimentary organic matter in the summer may be due to the photosynthetic incorporation of $^{15}N$-enriched nitrogen (DIN) or the spawning events of bivalves. Specific oyster tissues (gut, gill, and muscle) revealed different metabolic pathways, which were determined through analysis of ${\delta}^{13}C$ and ${\delta}^{15}N$ in each organ. The present results suggest the determination of carbon and nitrogen stable isotopes to be a useful approach in ecological research related to the food sources- metabolism of Crassostrea gigas.

• 농업과학연구
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• 제43권3호
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• pp.379-386
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• 2016

Four ruminally cannulated Holstein steers (BW $482.9{\pm}8.10kg$), fed low protein TMR (CP 11.7%) as a basal diet, were used to investigate changes in rumen fermentation and blood metabolism according to protein fraction, cornell net carbohydrates and protein system (CNCPS), and enriched feeds. The steers, arranged in a $4{\times}4$ Latin square design, consumed TMR only (control), TMR supplemented with rapeseed meal (AB1), soybean meal (B2), and perilla meal (B3C), respectively. The protein feeds were substituted for 23.0% of CP in TMR. Ruminal pH, ammonia-N, and volatile fatty acids (VFA) in rumen digesta, sampled through ruminal cannula at 1 h-interval after the morning feeding, were analyzed. For plasma metabolites analysis, blood was sampled via the jugular vein after the rumen digesta sampling. Different N fraction-enriched protein feeds did not affect (p > 0.05) mean ruminal pH except AB1 being numerically lower 1 - 3 h post-feeding than the other groups. Mean ammonia-N was statistically (p < 0.05) higher for AB1 than for the other groups, but VFA did not differ among the groups. Blood urea nitrogen was statistically (p < 0.05) higher for B2 than for the other groups, which was rather unclear due to relatively low ruminal ammonia-N. This indicates that additional studies on relationships between dietary N fractions and ruminant metabolism according to different levels of CP in a basal diet should be required.

• Journal of Applied Biological Chemistry
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• 제48권1호
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• pp.35-37
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• 2005

Campsis grandiflora K. Schum. flower was extracted with 80% aqueous MeOH, and concentrated extract was successively partitioned with EtOAc, n-BuOH, and $H_2O$. From n-BuOH fraction, two cyclohexylethanoids were isolated through repeated silica gel and Sephadex LH-20 column chromatographies. Based on physico-chemical data obtained from NMR, MS, and IR, chemical structures of compounds were determined as 1,4-dihydroxy-3,4-(epoxyethano)-5-cyclohexene (1) and cornoside (2). These compounds were isolated for the first time from C. grandiflora K. Schum flower.

• Molecules and Cells
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• 제23권2호
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• pp.154-160
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• 2007

An Arabidopsis hy4 mutant that is specifically impaired in its ability to undergo blue light dependent photomorphogenesis was used to identify cryptochrome 1 signaling-related components. Proteomic analysis revealed about 205 differentially expressed protein spots in the blue light-irradiated hy4 mutant compared to the wild-type. The proteins corresponding to 28 up-regulated and 33 down-regulated spots were identified. Obvious morphological changes in the hy4 mutant were closely related to the expression of various transcription factors. Our findings suggest that blue light signals may be involved in many cellular processes including disease resistance and stress responses.

• 대한수의학회지
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• 제35권4호
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• pp.691-698
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• 1995

We used rats as the experimental animal for the elucidation of metabolic patterns and pharmacokinetic profiles of SMZ in the rat, by use of the urine and plasma from predetermined intervals, respectively. Information herefrom would give some insight into species differences and sex differences in the metabolism and pharamcokinetics of drugs, at least SMZ in particular. Results would be summarized as follows: 1. There were two hydorxy metabolites(5-hydroxysulfamethazine and 6-hydroxyethylsulfamethazine) and an acetyl derivative($N_4$-acetyl sulfamethazine) in the 24h-collected urine, on confirmation with each standard materials. There were also two unknown metabolites therein. 2. In the viewpoint of quantitative aspect, $N_4$-acetylsulfamethazine was the largest, hence it is assumed that the acetyl pathway is the major one in the metabolism of SMZ in the rat. 3. As regards sex difference in the rat, the male had more metabolic capacity than the female in metabolism of SMZ. 4. The concenteration-time curves of sulfamethazine(20mg/kg, po) in the plasma compartment were fitted to a one-compartment open model by use of a computer program(NONLIN). 5. There were significant differences(P<0.05) in the pharmacokinetics of sulfamethazine between two sexes in the rat, with higher disposition rate in the male. 6. The emergence of $N_4AcSMZ$ metabolized from SMZ was fast in the plasma of the rat. Half-life of $N_4AcSMZ$ was also. significantly different(P<0.05) between two sexes, suggesting differences in the eliminatory capacity of $N_4AcSMZ$.

• Asian-Australasian Journal of Animal Sciences
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• 제2권3호
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• pp.340-342
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• 1989