• The Plant Pathology Journal
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• 제35권6호
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• pp.575-584
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• 2019

Colletotrichum acutatum is a species complex responsible for anthracnose disease in a wide range of host plants. Strain C. acutatum KC05, which was previously isolated from an infected pepper in Gangwon Province of South Korea, was reidentified as C. scovillei using combined sequence analyses of multiple genes. As a prerequisite for understanding the pathogenic development of the pepper anthracnose pathogen, we optimized the transformation system of C. scovillei KC05. Protoplast generation from young hyphae of KC05 was optimal in an enzymatic digestion using a combined treatment of 2% lysing enzyme and 0.8% driselase in 1 M NH₄Cl for 3 h incubation. Prolonged incubation for more than 3 h decreased protoplast yields. Protoplast growth of KC05 was completely inhibited for 4 days on regeneration media containing 200 ㎍/ml hygromycin B, indicating the viability of this antibiotic as a selection marker. To evaluate transformation efficiency, we tested polyethylene glycol-mediated protoplast transformation of KC05 using 19 different loci found throughout 10 (of 27) scaffolds, covering approximately 84.1% of the entire genome. PCR screening showed that the average transformation efficiency was about 17.1% per 100 colonies. Southern blot analyses revealed that at least one transformant per locus had single copy integration of PCR-screened positive transformants. Our results provide valuable information for a functional genomics approach to the pepper anthracnose pathogen C. scovillei.

• 대한환경공학회지
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• 제32권5호
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• pp.417-426
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• 2010

본 연구에서는 가죽 생산 공정 중 원피 무게의 50% 이상 고형 폐기물로 발생하는 콜라겐 단백질의 섬유 기재에 미모사(Catechol Tannin) 및 채스트넛(Pyrogallol Tannin)과 같은 식물성 탄닌물질을 다양한 조건에서 고정화시킨 10 가지 다른 종류의 바이오 흡착제를 제조하였다. 제조한 각 바이오 흡착제들의 중금속 제거용 흡착제로서의 성능 평가를 위하여 Cu(II), Cd(II), Zn(II), Pb(II), Cr(III) 이온을 함유한 인공 오염수를 사용하여 다양한 반응 조건에서의 회분식 실험을 실시하였으며, 중금속들의 제거 특성을 규명하였다. 미모사를 탄닌물질로 사용하여 콜라겐에 고정화 반응을 시켰을 때 섬유 번들 내부로의 미모사의 침투력은 나프탈렌계 침투제의 주입량에 비례 하였다; 3% ${\geq}$ 1.5% > 0%. 모든 바이오 흡착제들에서 pH 3.0 이하에서는 중금속 이온들의 제거는 거의 일어나지 않았으나 pH 3.0 이상에서 중금속의 제거율이 급격히 발생하였으며 Zn(II)을 제외한 나머지 중금속이온들은 pH 6.0 이상에서는 거의 완전히 제거되었다. Cr(III)의 경우에는 바이오 흡착제 종류별 제거량이 매우 유사한 경향을 나타내었으나 Cu(II), Zn(II), Pb(II)의 제거에서는 축합형 탄닌(미모사)에 비해 이온결합이 가능한 다량의 카르복실기를 함유한 가수분해형 탄닌(채스트넛)을 사용하여 고정화시킨 바이오 흡착제에서 높은 제거능을 보였다. S10 바이오 흡착제에 대한 Pb(II) 및 Cu(II) 중금속 이온들의 흡착은 이온농도가 1,000배 변화거나 경쟁이온 화학종을 일하전 및 이하전 화학종을 사용하였을 때 영향을 받지 않았다.

• Nutrition Research and Practice
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• 제6권2호
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• pp.97-105
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• 2012

$Schizandra$ $chinensis$ Baillon is a traditional folk medicine plant that is used to treat and prevent several inflammatory diseases and cancer in Korea, but the underlying mechanisms involved in its anti-allergic activity are not fully understood. This study was designed to investigate mechanisms of anti-allergic activity of a $Schizandra$ $chinensis$ Baillon water extract (SCWE) in immunoglobulin E (IgE)-antigen complex-stimulated RBL2H3 cells and to assess whether gastric and intestinal digestion affects the anti-allergic properties of SCWE. Oxidative stress is an important consequence of the allergic inflammatory response. The antioxidant activities of SCWE increased in a concentration-dependent manner. RBL-2H3 cells were sensitized with monoclonal anti-dinitrophenol (DNP) specific IgE, treated with SCWE, and challenged with the antigen DNP-human serum albumin. SCWE inhibited ${\beta}$-hexosaminidase release and expression of interleukin (IL)-4, IL-13, and tumor necrosis factor-alpha (TNF-${\alpha}$) mRNA and protein in IgE-antigen complex-stimulated RBL2H3 cells. We found that digested SCWE fully maintained its antioxidant activity and anti-allergic activity against the IgE-antigen complex-induced activation of RBL-2H3 cells. SCWE may be useful for preventing allergic diseases, such as asthma. Thus, SCWE could be used as a natural functional ingredient for allergic diseases in the food and/or pharmaceutical industries.

• Animal Bioscience
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• 제34권4호
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• pp.642-651
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• 2021

Objective: This study aimed to determine the effects of different roughages in total mixed ration (TMR) inoculated with or without coculture of Lactobacillus acidophilus (L. acidophilus) and Bacillus subtilis (B. subtilis) on in vitro rumen fermentation and microbial population. Methods: Three TMRs formulations composed of different forages were used and each TMR was grouped into two treatments: non-fermented TMR and fermented TMR (F-TMR) (inoculated with coculture of L. acidophilus and B. subtilis). After fermentation, the fermentation, chemical and microbial profile of the TMRs were determined. The treatments were used for in vitro rumen fermentation to determine total gas production, pH, ammonianitrogen (NH3-N), and volatile fatty acids (VFA). Microbial populations were determined by quantitative real-time polymerase chain reaction (PCR). All data were analyzed as a 3×2 factorial arrangement design using the MIXED procedure of Statistical Analysis Systems. Results: Changes in the fermentation (pH, lactate, acetate, propionate, and NH3-N) and chemical composition (moisture, crude protein, crude fiber, and ash) were observed. For in vitro rumen fermentation, lower rumen pH, higher acetate, propionate, and total VFA content were observed in the F-TMR group after 24 h incubation (p<0.05). F-TMR group had higher acetate concentration compared with the non-fermented group. Total VFA was highest (p<0.05) in F-TMR containing combined forage of domestic and imported source (F-CF) and F-TMR containing Italian ryegrass silage and corn silage (F-IRS-CS) than that of TMR diet containing oat, timothy, and alfalfa hay. The microbial population was not affected by the different TMR diets. Conclusion: The use of Italian ryegrass silage and corn silage, as well as the inoculation of coculture of L. acidophilus and B. subtilis, in the TMR caused changes in the pH, lactate and acetate concentrations, and chemical composition of experimental diets. In addition, F-TMR composed with Italian ryegrass silage and corn silage altered ruminal pH and VFA concentrations during in vitro rumen fermentation experiment.

• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1327-1332
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• 2004

The hemA gene encoding 5-aminolevulinic acid synthase (ALAS) was cloned from Rhodobacter capsulatus, and its nucleotide sequence was determined. DNA sequencing data revealed one open reading frame coding for a protein with 401 amino acids that displayed high similarity to the amino acid sequences of other known ALASs. The hemA gene was then cloned and expressed under the control of constitutive promotor in E. coli. The recombinant E. coli strain was able to accumulate 5-aminolevulinic acid to 21 mM in the liquid medium supplemented with 45 mM glycine and 120 mM succinate. In addition, a marked effect of the pH of the culture medium on ALA production was observed, and the optimum pH for culture medium was determined to be 5.8-6.3.

• Journal of Microbiology and Biotechnology
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• 제21권11호
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• pp.1147-1150
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• 2011

Xanthomonas oryzae causes rice bacterial blight, which has been reported as one of the most destructive diseases of rice. Metabolites were identified through cheonggukjang, a traditional Korean fermented soybean product fermented by the Bacillus spp., to control the bacteria. HPLC, MS, and UPLC-Q-TOF-MS analyses were performed to identify metabolites responsible for antimicrobial activity. In this analysis, the m/z values of 253.0498, 283.0600, 269.0455, 992.6287, and 1,006.6436 were identified as daidzein, glycitein, genistein, surfactin B, and surfactin A, respectively. The levels of surfactin B and surfactin A were found to be high at 24 h (4.35 ${\mu}g$/ml) and 36 h (3.43 ${\mu}g$/ml) of fermentation, respectively.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.2083-2086
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• 2009

Human vascular endothelial growth factor receptor 2 (hVEGFR2) is an important signaling protein involved in angiogenesis and attractive drug target in cancer therapy. It has been reported that flavonols, a class of flavonoids, have anti-angiogenic activity in various cancer cell lines. We performed receptor-oriented pharmacophore based in silico screening for identification of hVEGFR2 inhibitors from flavonol database. By comparing with three X-ray complex structures of hVEGFR2 and its inhibitors, we evaluated the specific interactions between inhibitors and receptors and determined a single pharmacophore map. This map consisted of four features, a hydrogen bonding acceptor (HBA) on Cys917, two hydrogen bonding donors on Glu917 (HBD1) and Glu883 (HBD2), and one hydrophobic interaction (Lipo) with Val846, Ala864, Val897, Val914 and Phe1045 of hVEGFR2. Using this map, we searched a flavonol database including 9 typical flavonols and proposed that five flavonols, kaempferol, quercetin, fisetin, morin, and rhamnetin can be potent inhibitors of hVEGFR2. 3-OH of C-ring and 4’-OH of B-ring of flavonols are the essential features for hVEGFR2 inhibition. This study will be helpful for understanding the mechanism of inhibition of hVEGFR2 by natural products.

• KSBB Journal
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• 제25권5호
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• pp.471-477
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• 2010

In order to improve bio-ethanol productivity by various cultivation methods in this paper, the culture modes using food wastes, such as batch culture, high-cell-density fermentation, SSF (simultaneous saccharification and fermentation) by fill & draw, continuous culture by fill & draw were performed and their productivities were compared. SSFs by fill & draw were performed by continuous decompression using 1 L evaporator system, and by 10 L bioreactor without decompression. In addition, the continuous cultures by fill & draw mode using SFW (saccharafied food wastes) medium were performed by changes of 40% culture broth with intervals of 12 h (0.03 $h^{-1}$), 6 h (0.07 $h^{-1}$), 3 h (0.13 $h^{-1}$). Consequently, productivities of bio-ethanol were 2.52 g/L-h and 1.30 g/L-h in batch culture and high- cell-density fermentation, respectively. The productivities of SSF by fill & draw showed 2.24 g/L-h and 2.03 g/L-h in continuous decompression with 1 L evaporator and 10 L bioreactor without decompression, respectively. Also, the productivities in continuous culture by fill & draw modes showed 2.02 g/L-h, 4.07 g/L-h and 6.25 g/L-h by medium change with intervals of 12 h, 6 h, and 3 h, respectively. In conclusion, the highest ethanol productivity was obtained in the continuous culture mode by fill & draw with dilution rate of 0.13 $h^{-1}$.

• 한국응용과학기술학회지
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• 제33권1호
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• pp.75-82
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• 2016

급속열분해 기술은 바이오매스를 수송용 연료와 고품질의 석유화학 생산물로 업그레이드 할 수 있는 바이오오일을 만드는 유망한 수단으로 주목 받고 있다. 이러한 기대에도 불구하고 연료와 석유화학 생산물의 상업성은 바이오오일의 높고 잘 변하는 점도, 많은 수분과 산소 함량, 낮은 발열량 및 산성도와 같은 상당히 바람직하지 않은 특징 때문에 한계가 있다. 그래서 본 연구는 가압증류를 통해 바이오오일의 품질 개선을 목표로 수행하였다. 가압증류에 따른 바이오오일의 특성 변화를 알아보기 위하여 0.8~1.4 mm 크기의 굴참나무(Quercus variabilis) 시료 600 g을 $465^{\circ}C$에서 1.6초 동안 급속열분해하여 바이오오일을 제조하고, 감압증류(100hPa) 온도는 대조구, $40^{\circ}C$, 50, 60, 70 및 80에서 각각 30분간 처리하였다. 급속열분해를 통해 생산된 바이오오일, 바이오차 및 가스는 각각 62.6 wt%, 18.0 및 19.3으로 나타났다. 또한 온도별로 생성된 바이오오일은 수분함량 0.9~26.1 wt%, 점도 4.2~11.0 cSt, 발열량 3,893~5,230 kcal/kg 및 pH 2.6~3.0 수준으로 긍정적 효과가 나타났다. 이러한 바이오오일 품질개선에도 불구하고 점도는 반대로 증가했으며 여전히 높은 산소 함량, 낮은 발열량 및 산성도 때문에 바이오오일을 실용적인 연료로 사용하기 위해서는 지속적으로 품질 개선이 필요하다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.230-234
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• 2005

Fabrication of MEA is important factor for proton exchange membrane fuel cell (PEMFC). MEA of PEMFC with hot pressing and direct coating method were prepared, and performances were evaluated and compared each other. The effect of MEA preparation methods, hot pressing methods and direct coating methods, on the cell performance was analyzed by impedance spectroscopy and SEM. The performance of PEMFC with direct coating method was better than with hot pressing method because membrane internal resistance and membrane-interfacial resistance were reduced by elimination of hot pressing process in MEA fabrication. In addition the micro structure of MEA with direct coating method reveals uniform interface between membrane and catalyst layer.