• Journal of Biosystems Engineering
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• 제28권2호
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• pp.151-156
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• 2003

This study was performed to investigate the effect of light quality on evapotranspiration and graft-taking characteristics of watermelon grafted seedlings using blue, red and far-red light-emitting diodes (LED). At initial stage of graft-taking, blue light increased the evapotranspiration rate (EVTR) of grafted seedlings as compared to effects of red and far-red on EVTR of grafted seedlings. Grafted seedlings graft-taken under red and blue LED showed the high graft-taking of 100% and 96%, respectively. However, grafted seedlings graft-taken under far-red LED showed the graft-taking of 80% and survival of 60% with low seedlings quality after hardening. The stem of grafted seedlings graft-taken under red light was elongated but blue light suppressed the stem elongation. The leaf area of grafted seedlings graft-taken under red light was increased. It is concluded that the effect of light quality using LED on graft-taking of watermelon grafted seedlings was significantly recognized. Considering the duration of quality of grafted seedlings graft-taken under artificial lighting, LED could be used as an effective lighting sources to validate the continuance of seedling quality.

• Food Science and Biotechnology
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• 제18권4호
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• pp.849-854
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• 2009

Water extracts of injinssuk (Artemisia iwayomogi Kitamura) (WE) were obtained from the dried and ground leaves and stems of injinssuk. The WE was further fractionated into crude polysaccharide (C-PS) and nonpolysaccharide fractions (N-PS). The protective activities against the tert-butyl hydro peroxide induced mutangenecity on Escherichia coli PQ37 and reactive oxygen species scavenging activity of the WE, C-PS, and N-PS were studied. The WE obtained from leaves showed a significantly higher inhibitory effect on the mutagenicity than WE from stem. The WE obtained from the leaves having higher crude polysaccharide content but lower content of total carbohydrates had significantly higher antimutagenicity than that from the leaves with lower crude polysaccharide but higher total carbohydrate contents. Further study showed that C-PS fraction showed markedly stronger antimutagenic effect than N-PS. C-PS was also more effective than N-PS for hydroxyl radical scavenging activity, but was similar to N-PS in superoxide radical scavenging activity.

• 한국농공학회논문집
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• 제54권6호
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• pp.143-150
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• 2012

바이오에탄올 생산공정은 당 (Sugar)을 기반으로 하는 공정과 합성가스를 이용하는 공정으로 분류할 수 있다. 이 가운데 합성가스를 이용하는 공정은 촉매를 이용한 화학적 공정과 혐기성 발효에 의한 생물학적 공정의 두 가지로 나뉜다. Clostridium ljungdahlii는 일산화탄소와 수소가 주요 성분으로 구성되는 합성가스를 이용하여 에탄올과 아세트산을 생산할 수 있는 균주 중의 하나로 알려져 있다. 합성가스 발효공정에서 pH는 미생물의 증식과 에탄올 등의 생산에 아주 중요한 요인 중의 하나이다. 본 연구에서는 pH 조건이 미생물의 생장과 에탄올 생산성에 미치는 영향을 조사하였다. C. ljungdahlii 배양은 엄격한 혐기성 조건에서 100 ml의 serum bottle과 pH 제어가 가능한 반응기를 이용한 실험결과, 회분식 배양 조건에서는 미생물의 생장과 에탄올 생산을 위한 최적 초기 pH는 7.0로 나타났다. 미생물 농도는 0.57 g/L, 에탄올 농도 0.91 g/L로 나타났다. pH 4.5 이하에서는 미생물의 생장이 멈추는 것으로 나타났다. pH 제어가 가능한 생물반응기에서는 pH 6.0 일때 에탄올 생산량이 pH 7.0 일때 보다 높게 나타났다. 일정 수준의 미생물 농도를 유지한 조건에서 합성가스를 기포식으로 주입하고 pH 5.9에서 5.4까지 제어하였을 때 미생물량과 에탄올 농도가 증가하였다. 60 시간이 지난 후에 미생물의 농도는 0.498 g/L, 에탄올은 1.056 g/L까지 이르렀다.

• Journal of Biosystems Engineering
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• 제27권3호
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• pp.227-234
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• 2002

This study was conducted to nondestructively estimate the volumetric information of peach and pit and to visualize the 3D information of internal structure from magnetic resonance imaging(MRI) data. Bruker Biospec 7T spectrometer operating at a proton reosonant frequency of 300 MHz was used for acquisition of MRI data of peach. Image processing algorithms and visualization techniques were implemented by using MATLAB (Mathworks) and Visualization Toolkit(Kitware), respectively. Thresholding algorithm and Kohonen's self organizing map(SOM) were applied to MRI data fur region segmentation. Volumetric information were estimated from segemented images and compared to the actual measurements. The average prediction errors of peach and pit volumes were 4.5%, 26.1%, respectively for the thresholding algorithm. and were 2.1%, 19.9%. respectively for the SOM. Although we couldn't get the statistically meaningful results with the limited number of samples, the average prediction errors were lower when the region segmentation was done by SOM rather than thresholding. The 3D visualization techniques such as isosurface construction and volume rendering were successfully implemented, by which we could nondestructively obtain the useful information of internal structures of peach.

• Journal of Microbiology and Biotechnology
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• 제16권5호
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• pp.786-790
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• 2006

Cellular components of Lactococcus lactis ssp. lactis (heat-killed whole cells, cytoplasm, and cell walls) were tested for their in vivo immunopotentiating activity. Peritoneal macrophages from mice orally administered with heat-killed whole cells exhibited significantly greater phagocytic activity than the groups administered with cell-wall fraction or cytoplasm fraction. The cytotoxicity of natural-killer cells was the highest in the group administered with whole cells, and the production of cytokines ($IFN-\gamma$, IL-2, and IL-12) in spleen cells was significantly higher, when cellular components were injected, and it tended to be higher in the cell-wall and cytoplasm groups than in the whole-cell group. Interestingly, the cytokine production of Peyer's patch cells was high, when cytoplasm fractions were administered. These results demonstrate that whole cells and cytoplasm and cell-wall fractions of L. lactis ssp. lactis have immunopotentiating activities, which are related to the stimulation of Peyer's patches.

• 한국미생물·생명공학회지
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• 제34권4호
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• pp.357-362
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• 2006

A growth inhibition assay using Chlorella sp. AG 10002 based on the OECD 201 standard test procedure was applied to the toxicity testing of endosulfan and its reported metabolites. Comparison of dry cell weight, optical density (OD) at 680 nm, and chlorophyll a concentration indicated that optical density at 680 nm of culture broth is convenient, rapid, and accurate method for cell growth. In this microalgae system, the $IC_{50}$ values of endosulfan, endosulfan sulfate, endosulfan lactone, and endosulfan ether were determined as 9.45, 18.8, 18.2 and 37.5 mg/L, respectively. In a while, endosulfan diol did not show a significant toxicity up to 50 mg/L. Since endosulfan is liable at acidic or alkaline conditions, treatment of endosulfan in pH 3, 4, and 11 for 3 days resulted in reduced toxicity, as expected. These results suggested that the microalgae system is useful to evaluate various toxic chemicals and provide a new notion for bioremediation of endosulfan in aqueous systems.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.120-120
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• 2018

Intestinal microbiota is strongly connected to health of host. It has been reported that not only metabolic disease like diabetes and obesity, but psychological diseases are affected by composition of intestinal microbiota. To figure it out the importance of the composition and relationship between disease and microbiota, intensive researches have done with human and experimental animals. But, the composition of the intestinal microbiota could be affected by several factors such as experimental environments, feeding, water, and bedding. As a result, the data from each experimental group might be diverse. It also affects experiments about biological activities of plant materials. In this study, mouse intestinal bacteria were isolated from fresh feces and identified by 16S rRNA gene to use in biological activities of natural medicines. The fecal supernatant was anaerobically incubated at $37^{\circ}C$ for 48 hours. Colonies were picked up separately and incubated again in same condition to increase quantity to analyze and stock. The bacteria strains were listed up and could be used for many researches including biological activities of plant materials and change in composition of intestinal bacteria itself.

• 한국수산과학회지
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• 제49권2호
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• pp.124-130
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• 2016

To effectively remove salts from Suaeda japonica, extracts, an electrodialysis system was developed. The biological activities of non-desalted (NDS) and desalted S. japonica (DS) extracts were compared. The DS extract exhibited superior polyphenolic (6.26%) and carbohydrate (28.56%) contents. The IC₅₀ values of the DS extract against DPPH radicals and hydrogen peroxide were 0.22 and 0.68 mg/mL, respectively, which was higher than that of the NDS extract. Neither the DS nor the NDS extract was cytotoxic in RAW 264.7 macrophages. Additionally, the DS extract had a higher NO inhibitory effect compared to the NDS extract in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. These data indicate that DS extracts have greater biological activity than do ND extracts, and application of the electrodialysis process may be useful in marine bioresource applications.

• The Plant Pathology Journal
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• 제34권5호
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• pp.445-450
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• 2018

Bacteriophages, bacteria-infecting viruses, have been recently reconsidered as a biological control tool for preventing bacterial pathogens. Erwinia amylovora and E. pyrifoliae cause fire blight and black shoot blight disease in apple and pear, respectively. In this study, the bacteriophage phiEaP-8 was isolated from apple orchard soil and could efficiently and specifically kill both E. amylovora and E. pyrifoliae. This bacteriophage belongs to the Podoviridae family. Whole genome analysis revealed that phiEaP-8 carries a 75,929 bp genomic DNA with 78 coding sequences and 5 tRNA genes. Genome comparison showed that phiEaP-8 has only 85% identity to known bacteriophages at the DNA level. PhiEaP-8 retained lytic activity up to $50^{\circ}C$, within a pH range from 5 to 10, and under 365 nm UV light. Based on these characteristics, the bacteriophage phiEaP-8 is novel and carries potential to control both E. amylovora and E. pyrifoliae in apple and pear.

• Food Science and Biotechnology
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• 제15권6호
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• pp.877-883
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• 2006

The immunostimulatory activities of Lactobacillus plantarum, the major microorganism in kimchi fermentations were investigated. Five strains of L. plantarum exhibited weak immunopotentiating activity, but L. plantarum PS-21 showed as strong a mitogenic activity as Bifidobacterium adolescentis M101-4, a known positive strain. It is of interest that, L. plantarum PS-21 stimulated proliferation of Peyer's patch cells, one of the most important tissues in the gut-associated lymphoreticular system. Cell' wall fractions from L. plantarum PS-21 also showed strong mitogenic activity compared with the soluble cytoplasmic fraction. A peptidoglycan fraction (PG) extracted from the cell wall of L. plantarum PS-21 was identified as an active mitogenic component when used in murine lymph node and spleen cell test systems. PG showed dose-dependent mitogenic activity and significantly enhanced antibody production in lymph node cells when studied in vitro. The lysosomal enzyme activity of murine peritoneal macrophages was increased when analyzed following injection of PG to the host animal. Furthermore, PG enhanced the production of cytokines such ($TNF-{\alpha}$ and IL-6) in the in vitro culture of RAW 264.7 macrophage cells.