• 대한수의학회지
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• 제43권4호
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• pp.615-624
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• 2003

Vascular smooth muscle relaxation is modulated by an increase in cGMP subsequent to nitric oxide (NO) production by endothelial cells. The effects of cAMP and cGMP phosphodiesterase (PDE) inhibitors were investigated in phenylephrine-precontracted rat aorta rings by using the specific inhibitors of PDE I, III, IV and V as relaxing agents (calmodulin-activated PDE inhibitors, IBMX and $W_7$, type I; cAMP-specific PDE inhibitors, milrinone, type IV; Ro 20-1724, type III and cGMP-specific PDE inhibitor, zaprinast, type V). All the PDE inhibitors produced a concentration-dependent relaxation in the ring with intact endothelium (+E). Except for milrinone, all the PDE inhibitors-induced relaxations were inhibited by removal of extracellular $Ca^{2+}$, $N^G$-nitro-L-arginine, $N^G$-nitro-L-arginine methyl ester, methylene blue (MS) or nifedipine. The specific PDE I and PDE IV inhibitors both produced endothelium-independent relaxations which were inhibited by MS in -E rings. However, zaprinast had no effect in -E rings. Except for milrinone, sodium nitroprusside (a NO donor)-induced relaxation was significantly augmented by all PDE inhibitors in +E rings. The results suggest that I) the vasorelaxant properties of IBMX, $W_7$, Ro 20-1724 and zaprinast are dependent on endothelium or on interaction with $Ca^{2+}$ regulation, 2) each PDE is differently distributed in vascular tissues (endothelial and smooth muscle cells), 3) the vasodilations of PDE inhibitors are due to the increase of cAMP and cGMP formation through inhibition of cAMP- and cGMP-PDE and 4) the vasodilation action of milrinone does not involve in endothelial-cyclic nucleotide system.

• 생명과학회지
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• 제24권10호
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• pp.1132-1136
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• 2014

울금(Curcuma longa L., turmeric)은 생강과(Zingiberaceae)에 속하는 다년생 초본 식물로 전통적으로 한약재, 향신료 및 식용으로 사용되어 왔다. 강력한 항산화 작용, 울금 에탄올 추출물의 항산화 활성, 항돌연변이성, 항염증, 항암성 및 항균성 효과 등이 보고되고 있다. 그러나 울금에 대한 생리활성 연구는 이미 많이 이루어져 있는 반면 울금에 대한 독성평가는 이루어지지 않았다. 본 연구는 울금 에탄올 추출물에 대한 안정성을 확보하기 위하여 단회경구투여 독성시험을 BALB/c 마우스를 이용하여 실시하였다. 울금 에탄올 추출물은 0, 20, 200, 2,000 mg/kg 농도로 경구 투여하였으며, 14일간 관찰 후 희생시켰다. 울금 에탄올 추출물 투여 후 운동성, 비정상적 임상증상, 부검 소견상, 체중의 유의적인 변화는 관찰되지 않았다. 혈액 생화학적 측정과 다양한 장기의 무게에서도 유의적인 변화를 관찰할 수 없었다. 이들 결과로 미루어볼 때 울금 에탄올 추출물의 단회 투여에 따른 치사량은 2,000 mg/kg 이상을 상회할 것으로 추정되며 급성독성에 어떠한 유해성이 없다는 것을 의미한다.

• 한국잠사곤충학회지
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• 제42권1호
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• pp.48-57
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• 2000

This study was undertaken to figure out the effects of hydrolysis conditions on the solubility of insoluble sericin, molecular weight distribution and thermal characteristics of hydrolysates in enzymatic hydrolysis by Alcalase 2.5L. It was indicated that the optimum treatment temperature and pH for the insoluble sericin were 50$\^{C}$ and 11, respectively. When the insoluble sericin was hydrolyzed with a various treatment conditions, the solubility of all hydrolysates were represented above 85% at given conditions. As the enzyme concentration increased, the solubility increased roughly, but the solubility increasement ratio was less above 2% enzyme concentration. As the treatment time increased, the solubility was also increased. It was showed in the molecular weight distribution of hydrolysates treated various enzyme concentrations and treatment times that when enzyme concentrations were 0.5, 2, 3%, the peaks of the distribution curve were shifted to left side which meant low molecular weight and was distributed much quantity with shifted to be left side, but treatment time was 6 hr. the peak was shifted to right side. When enzyme concentration was 5% and treatment time was below 2 hr., the peaks were shifted to right side, but treatment time was above 4hr. the peak was shifted to left side. The number-average molecular weights were distributed from 300 to 800 and those were decreased when treatment time was up to 4 hr., but increased a little when treatment time was 6hr. It was showed in the DSC curves of hydrolysates treated with treatment time of 0.5, 1, 2, 4, 6 hr. fixed 1% o.w.s enzyme concentration and control that the endothermic peak was observed near at 200$\^{C}$. The denaturation peak of the hydrolysates depending on treatment times had a tendency to shift to higher temperature. But, when the treatment time was 6 hr., the peak was shifted to lower temperature comparing another hydrolysates.

• 한국미생물·생명공학회지
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• 제20권1호
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• pp.102-109
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• 1992

김치의 발효온도를 5, 20 및 $30^{\circ}C$로 달리하여 발효기간 중의 젖산균의 경시적인 변화를 선택배지를 이용하여 젖산균군별로 계수하는 방법으로 비교하고 이들 젖산균을 분리하여 형태적, 배양적 및 생리적 특징에 따라 동정하였다. Leuconostoc, Lactobacillus, Streptococcus 및 Pediococcus속의 각 젖산균의 경지적인 변화는 각 온도에 있어서 그 양상이 비슷하고 온도가 높을수록 빨리 진행되었다. 이들 중 Leuconostoc 및 Lactobacillus가 높은 분포를 나타내었으며 낮은 온도에서는 Leuconostoc는 증가하고 기타의 젖산균은 감소하는 경향이 있었다.

• 한국작물학회지
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• 제56권3호
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• pp.255-263
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• 2011

Projected increases in atmospheric $CO_2$ concentration ([$CO_2$]) and temperature ($T_a$) have the potential to alter in rice growth and yield. However, little is known about whether $T_a$ warming with elevated [$CO_2$] modify plant architecture. To better understand the vertical profiles of leaf area index (LAI) and the flag leaf morphology of rice grown under elevated $T_a$ and [$CO_2$], we conducted a temperature gradient field chamber (TGC) experiment at Gwangju, Korea. Rice (Oryza sativa L. cv. Dongjin1ho) was grown at two [$CO_2$] [386 (ambient) vs 592 ppmV (elevated)] and three $T_a$ regimes [26.8 ($\approx$ambient), 28.1 and $29.8^{\circ}C$] in six independent field TGCs. While elevated $T_a$ did not alter total LAI, elevated [$CO_2$] tended to reduce (c. 6.6%) the LAI. At a given canopy layer, the LAI was affected neither by elevated [$CO_2$] nor by elevated $T_a$, allocating the largest LAI in the middle part of the canopy. However, the fraction of LAI distributed in a higher and in a lower layer was strongly affected by elevated $T_a$; on average, the LAI distributed in the 75-90 cm (and 45-60 cm) layer of total LAI was 9.4% (and 35.0%), 18.8% (25.9%) and 18.6% (29.2%) in ambient $T_a$, $1.3^{\circ}C$ and $3.0^{\circ}C$ above ambient $T_a$, respectively. Most of the parameters related to flag leaf morphology was negated with elevated [$CO_2$]; there were about 12%, 5%, 7.5%, 15% and 21% decreases in length (L), width (W), L:W ratio, area and mass of the flag leaf, respectively, at elevated [$CO_2$]. However, the negative effect of elevated [$CO_2$] was offset to some extent by $T_a$ warming. All modifications observed were directly or indirectly associated with either stimulated leaf expansion or crop phenology under $T_a$ warming with elevated [$CO_2$]. We conclude that plant architecture and flag leaf morphology of rice can be modified both by $T_a$ warming and elevated [$CO_2$] via altering crop phenology and the extent of leaf expansion.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.71-71
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• 2019

The genus Cenchrus (Poaceae), containing ca. 23 species, is distributed throughout Australia, Africa, Indian sub-continent, and America. In Korea, Cenchrus longispinus (Hack.) Fernald, especially introduced to Daecheong Island in 1999, is one of the most hazardous invasive plant which causes serious environmental threats, biodiversity damages and physically negative impact on humans and animals. Based on the next-generation sequencing (NGS) technology, we characterized the chloroplast (cp) genome sequences of C. longispinus which contains a large single copy (LSC; 80,223 bp), a small single copy (SSC; 12,449 bp), separated by a pair of inverted repeats (IRs; 22,236 bp). Additionally, we analyzed the cp genome sequences of Cenchrus echinatus L. which contains a large single copy (LSC; 80,220 bp), a small single copy (SSC; 12,439 bp), separated by a pair of inverted repeats (IRs; 22,236 bp). These cp genomes consist of 75 unique genes, 4 rRNA coding genes, 33 tRNA coding genes and 21 duplicated in the IR regions, of which the gene content and organization are similar to the other Poaceae cp genomes. We selected 40 potential regions in cp genomes of two Cenchrus species and one Korean Pennisetum species to develop new single nucleotide polymorphism (SNP) markers for identifying C. longispinus based on amplification-refractory mutation system (ARMS) technique. The markers, inferred from SNP in matK and ndhF genes, show effectiveness to recognize C. longispinus from C. echinatus and Korean native species Pennisetum alopecuroides (L.) Spreng.

• 한국축산식품학회지
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• 제38권1호
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• pp.99-109
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• 2018

In this study, we examined the inhibitory effect of L. plantarum Q180 on adipocyte differentiation in 3T3-L1 and reduction of adipocyte size in mice fed high-fat diet. L. plantarum Q180 inhibited the adipocyte differentiation of 3T3-L1 cells ($18.47{\pm}0.32%$) at a concentration of $400{\mu}g/mL$ ($10^8CFU/g$). As a result of western blot analysis, the expression of $C/EBP{\alpha}$ and $PPAR{\gamma}$ in 3T3-L1 adipocyte treated with $400{\mu}g/mL$ of L. plantarum Q180 decreased 35.16% and 40.07%, respectively, compared with the control. To examine the effects, mice were fed three different diets as follows: ND (n=6) was fed ND and orally administered saline solution; HFD (n=6), HFD and orally administered saline solution; and HFD+Q180 (n=6), HFD and orally administered L. plantarum Q180. After six weeks, the rate of increase of body weight was 13.7% lower in the HFD+Q180 group compared to the HFD group. In addition, the epididymal fat weights of the HFD+Q180 group were lower than that of the HFD group. The change of adipocyte size was measured in diet-induced obese mice. Consequently, the number of large-size adipose tissue was less distributed in the ND and HFD+Q180 groups than in the HFD group. L. plantarum Q180 has an effect on the inhibition of 3T3-L1 adipocyte differentiation, fat absorption and reduction of adipocyte size. L. plantarum Q180 could be applied to functional food products that help improve obesity.

• 한국축산식품학회지
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• 제40권5호
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• pp.772-784
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• 2020

This study was performed to investigate the effects of taste-related compounds and antioxidatve profiles of retorted samgyetang made from fresh and dried Cordyceps militaris (C. militaris) mushrooms. A total of 48 carcasses were prepared from commercial broilers (CB; Ross, 4 weeks old) and randomly distributed into eight different treatments. Each treatment group consisted of 6 chicken carcasses made with the addition of broth in different condition and concentration of C. militaris mushrooms. The addition concentration was based on the broth volume (v/w) under either fresh or dried conditions ranging from 0% as a control to 1%, 2%, and 3% of C. militaris mushrooms. C. militaris mushrooms contributed to an improvement of meat tenderness and the antioxidative profile that led to a greater suppression of lipid oxidation. The addition of C. militaris mushrooms at 2% could also enrich the flavor and taste-related compounds, particularly the increase in 5'-AMP and umami-related free amino acid compounds, L-aspartic acid and L-glutamic acid. Different addition forms of C. militaris mushrooms, particularly fresh or dried mushrooms, had only small effects on bioactive compounds, where the dried addition could possibly enrich samgyetang broth with higher cordycepin and adenosine contents than the fresh addition. Besides, the addition of C. militaris mushrooms in the dried form could also contribute to a higher antioxidative profile. Eventually, the addition of C. militaris mushrooms with a minimum addition of 2% contributed to an improvement of meat quality, antioxidative profile and flavor improvement of samgyetang.

• The Korean Journal of Ecology
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• 제13권3호
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• pp.215-224
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• 1990

The distribution of Spirodela polyrhiza and Lemna aequinoctialis was investigated and the limiting factors on the distribution were analyzed. At 66 sites in Korea, the presense or absense of duckweed were recorded and the water was sampled. The temperature, hardness, pH and contents of N, , , Na, K, Ca, Cu, Mg, Zn, Fe, Ni, Mn and Cd of water sampled were analyzed. The results were as follows; It seemed that the limiting factors influencing on the distribution was water temperature and concentration of . The critical temperature of the distribution of Spirodela and Lemna was presented 19.5$^{\circ}C$ and concentration of was limiting factor only in the distribution of S. polyrhiza. L. aequinoctialis was distributed in lower temperature than S. polyrhiza and it seemed that the distribution of L. aequinoctialis was not be influenced by the concentration of .

• 한국분말재료학회지
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• 제1권2호
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• pp.167-173
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• 1994

Cu-10wt%W composite powders have been manufactured by a high energy ball milling technique. The composite powders were pressed at 250 MPa and sintered in a dry hydrogen at 103$0^{\circ}C$ for 4 hours. After sintering, Cu-10wt%W composite materials were forged. And the arc-resistance of forged materials which have the same relative density of 94% has been tested. Composite particles, i.e. tungsten particles distributed homogeneously in the copper matrix, was formed after 480 min mechanical alloying. Densities of these sintered materials were ranged from 74 to 84%. Densification degree was due to the formation of composite powders. As the mechanical alloying time increased, the hardness was increased and tungsten particle size was decreased. Arc loss of the forged specimens was decreased as increasing the mechanical alloying time.