• Journal of Microbiology
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• 제34권4호
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• pp.341-348
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• 1996

The regulation of xylE gene expression was examined by using vector promoter and construction of genetically engineered microorganisms (GEMs) for application in microcosm. When the xylE gene wsa subcloned into pBluscript SK(+) under the control of lac promoter (pTY1) in E. coli, and the expression was induced by IPTG, the enzyme activity of catechol 2, 3-dioxygenase was increased 4.7 times more than that of the crude extracts from transformants harboring pTY1. We suggest that the xylE gene has its own promoter at the upstream portion, because it was able to be expressed even in the absence of IPTG. A recombinant plasmid, pSW3a harboring the xylE gene under the T7 promotor, showed the activity of 14.5 units/mg protein, higher than that of parental strain, E. coli PYT1. The xylE gene in recombinant plasmid pSW3a was used as reporter gene for the application in microcosm ecosystem, since it was used for detection of xylE-positive clones by catechol spray on the agar plates. The pSW3a in E. coli was introduced into Pseudomonas patida to construct GEM strain, and examined for the exxpression and functional stability in microcosms.

• KSBB Journal
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• 제18권5호
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• pp.347-351
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• 2003

초임계 이산화탄소를 이용하여 감초의 glycyrrhizic acid를 추출하기 위하여 일정 유속 (3 mL/min)에서 추출온도와 압력 보조용매의 종류와 첨가량에 대한 효과를 조사하여 보았다. 순수한 초임계 이산화탄소만을 사용해서 감초로부터 glycyrrhizic acid를 거의 추출할 수 없었다. 99.9% methanol, ethanol과 isopropanol을 보조용매로 초임계 이산화탄소에 첨가하여 추출한 경우, 추출수율의 증대에 큰 영향을 미치지 않았으나, 70% (v/v) aqueous methanol, ethanol과 isopropanol을 이산화탄소에 10% (v/v)으로 첨가한 경우에는 급격한 수율의 증대를 볼 수 있었고, 70% (v/v) aqueous methanol을 첨가하였을 때가 96.62 wt%로 가장 높은 회수율을 나타내었다. 한편, 70% (v/v) aqueous ethanol을 보조용매로 사용한 경우의 가장 높은 회수율과 빠른 추출속도를 나타낸 추출압력과 추출온도는 각각 40 MPa과 8$0^{\circ}C$였고, 이 조건하에서 다양한 농도의 aqueous ethanol (50∼90% (v/v))을 보조용매로 사용하였을 때 60% (v/v) aqueous ethanol을 보조용매로 첨가한 경우가 104.11 wt%로 가장 높은 회수율과 빠른 추출속도를 나타내었다. 또한 이산화탄소에 대한 60% (v/v) aqueous ethanol의 첨가량은 15% (v/v)을 첨가하였을 때 60분 내에 최고 회수율 (104.57 wt%)에 도달하였다.

• KSBB Journal
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• 제7권3호
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• pp.186-190
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• 1992

송충이의 유리 아미노산, 총 아미노산 조성과 총 지방산 조성을 규명하기 위해 Gas chromarography와 HPLC를 사용하여 분리 정량한 결과는 다음과 같다. 조지방 함량은 21.00%이고, 조단백질 함량은 58.47%로 조성되어 있다. 유리 아미노산의 총 함량은 3.65g/100g으로 조성되어 있으며, 유리 아미노산 중에서 필수 아미노산의 총 함량은 1.31g/100g으로 35.89%를 차지하고 있다. 총 아미노산의 총 함량은 41.20g/100g으로 조성되어 있으며 총 아미노산 중에서 필수 아미노산의 총 함량은 14.75g/100g으로 35.80%를 차지하고 있다. 총 지방산 조성은 $C_{18}$=26.81%로 제일 많이 함유되어 있고, $C_{16}$=19.09%, $C_{18:1}$=18.74%, $C_{18:3}$=15.33%, $C_{16:1}$=7.29%, $C_{20}$=5.21%순으로 함유되어 있으며, 불포화 지방산이 45.88%이고, 필수 지방산은 19.73%를 차지하고 있다.

• Journal of Microbiology and Biotechnology
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• 제18권1호
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• pp.88-94
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• 2008

Two sugar biosynthetic cassette plasm ids were used to direct the biosynthesis of a deoxyaminosugar. The pOTBP1 plasmid containing TDP-glucose synthase (desIII), TDP-glucose-4,6-dehydratase (desIV), and glycosyltransferase (desVII/desVIII) was constructed and transformed into S. venezuelae YJ003, a strain in which the entire gene cluster of desosamine biosynthesis is deleted. The expression plasmid pOTBP3 containing 4-aminotransferase (gerB) and 3,5-epimerase (orf9) was transformed again into S. venezuelae YJ003-OTBP1 to obtain S. venezuelae YJ003-OTBP3 for the production of 4-amino-4,6-dideoxy-L-glucose derivatives. The crude extracts obtained from S. venezuelae ATCC 15439, S. venezuelae YJ003, and S. venezuelae YJ003-OTBP3 were further analyzed by TLC, bioassay, HPLC, ESI/MS, LC/MS, and MS/MS. The results of our study clearly shows that S. venezuelae YJ003-OTBP3 constructs other new hybrid macrolide derivatives including 4-amino-4,6-dideoxy-L-glycosylated YC-17 (3, [M+ $Na^+$] m/z=464.5), methymycin (4, m/z=480.5), novamethymycin (6, m/z=496.5), and pikromycin (5, m/z=536.5) from a 12-membered ring aglycon (10-deoxymethynolide, 1) and a 14-membered ring aglycon (narbonolide, 2). These results suggest a successful engineering of a deoxysugar pathway to generate novel hybrid macrolide derivatives, including deoxyaminosugar.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1491-1499
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• 2010

Rhizosphere microorganisms possessing phytase activity are considered important for rendering phytate-phosphorus (P) available to plants. In the present study, the Citrobacter braakii phytase gene (appA) was overexpressed in rhizobacteria possessing plant growth promoting (PGP) traits, for increasing their potential as bioinoculants. AppA was cloned under the lac promoter in the broadhost-range expression vector pBBR1MCS-2. Transformation of the recombinant construct pCBappA resulted in high constitutive phytase activity in all of the eight rhizobacterial strains belonging to genera Pantoea, Citrobacter, Enterobacter, Pseudomonas (two strains), Rhizobium (two strains), and Ensifer that were studied. Transgenic rhizobacterial strains were found to display varying levels of phytase activity, ranging from 10-folds to 538-folds higher than the corresponding control strains. The transgenic derivative of Pseudomonas fluorescens CHA0, a well-characterized plant growth promoting rhizobacterium, showed the highest expression of phytase (~8 U/mg) activity in crude extracts. Although all transformants showed high phytase activity, rhizobacteria having the ability to secrete organic acid showed significantly higher release of P from Ca-phytate in buffered minimal media. AppA overexpressing rhizobacteria showed increased P content, and dry weight (shoot) or shoot/ root ratio of mung bean (Vigna radiata) plants, to different extents, when grown in semisolid agar (SSA) medium containing Na-phytate or Ca-phytate as the P sources. This is the first report of the overexpression of phytase in rhizobacterial strains and its exploitation for plant growth enhancement.

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1726-1736
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• 2013

Biosynthesis of indole-3-acetic acid (IAA) via the indole-3-pyruvic acid pathway involves three kinds of enzymes; aminotransferase encoded by aspC, indole-3-pyruvic acid decarboxylase encoded by ipdC, and indole-3-acetic acid dehydrogenase encoded by iad1. The ipdC from Enterobacter cloacae ATCC 13047, aspC from Escherichia coli, and iad1 from Ustilago maydis were cloned and expressed under the control of the tac and sod promoters in E. coli. According to SDS-PAGE and enzyme activity, IpdC and Iad1 showed good expression under the control of $P_{tac}$, whereas AspC was efficiently expressed by $P_{sod}$ originating from Corynebacterium glutamicum. The activities of IpdC, AspC, and Iad1 from the crude extracts of recombinant E. coli Top 10 were 215.6, 5.7, and 272.1 nmol/min/mg-protein, respectively. The recombinant E. coli $DH5{\alpha}$ expressing IpdC, AspC, and Iad1 produced about 1.1 g/l of IAA and 0.13 g/l of tryptophol (TOL) after 48 h of cultivation in LB medium with 2 g/l tryptophan. To improve IAA production, a tnaA gene mediating indole formation from tryptophan was deleted. As a result, E. coli IAA68 with expression of the three genes produced 1.8 g/l of IAA, which is a 1.6-fold increase compared with wild-type $DH5{\alpha}$ harboring the same plasmids. Moreover, the complete conversion of tryptophan to IAA was achieved by E. coli IAA68. Finally, E. coli IAA68 produced 3.0 g/l of IAA after 24 h cultivation in LB medium supplemented with 4 g/l of tryptophan.

• 한국식품과학회지
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• 제17권4호
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• pp.240-244
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• 1985

고려인삼(Panax ginseng C. A.. Meyer) 중의 $\beta$-amylase를 연구하기 위하여 조(粗)인삼 $\beta$-amylase 를 분리한 후 그의 성질을 조사하였다. 조인삼 $\beta$-amylase는 ammonium sulfate 0.2$\sim$0.6포화분획에 의하여 효과적으로 조제되었다. 조제된 본 효소는 전형적인 $\beta$-amylase의 작용을 하여 starch에서 maltose만을 생산하였으며 maltase의 활성은 나타내지 않았다. 본 효소는 pH5$\sim$9(특히 pH7$\sim$8), $40^{\circ}C$ 이하의 조건하에서 안정성을 나타내었고 최적pH 5.0, 최적온도 $35^{\circ}C$를 나타내었다. 본 호소는 기질(starch)농도 l2mg% 이하에서 기질농도에 비례하여 호소활성이 증가하였으며 Km치는 4.76mg%이었다. 또 본 효소는 $K^{+}$, $Na^{+}$, $An^{++}$,$Ca^{++}$, $Co^{++}$,$Mn^{++}$ $Zn^{++}$에는 영향을 받지 않았으나$Ag^{+}$, $Hg^{++}$,$Cd^{++}$, $Cu^{++}$,$ Al^{3+}$, and $Fe^{3+}$ 등에는 현저한 저해를 받았다.

• 한국식품영양학회지
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• 제26권3호
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• pp.375-382
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• 2013

The present study is designed to explore an anti-tumor activity on crude extracts of Oplopanax elatus. Water extractions of Oplopanax elatus were performed at $100^{\circ}C$(OeE-100). OeE-100 doses up to $62.5{\mu}g/m{\ell}$ had no cytotoxicity on the tumor cell lines in vitro. In experimental lung metastasis of colon26-M3.1 carcinoma or B16-BL6 melanoma, the prophylactic intravenous ($4{\sim}100{\mu}g/mouse$) or oral (2 mg/mouse) administration of OeE-100 significantly inhibited tumor metastasis as compared with tumor controls. Peritoneal macrophages stimulated with OeE-100 produced various cytokines such as TNF-${\alpha}$, IL-6 and IL-12. In an analysis of NK-cell activities, i.v. administration of OeE-100 ($10{\sim}100{\mu}g/mouse$) significantly augmented the cytotoxicity to YAC-1 tumor cells. Vaccination of mice with boiling-treated tumor cells (BT-vaccine) in combination with OeE-100 ($100{\mu}g/mouse$) showed higher inhibitions in tumor metastasis when compared with the mice of BT-vaccine treatment. In addition, the splenocytes from OeE-100 admixed BT-vaccine immunized mice secreted a higher concentration of Th1 type cytokine such as IFN-${\gamma}$. These results suggested that the OeE-100 stimulated immune system and was a good candidate adjuvant of anti-tumor immune responses.

• 동의생리병리학회지
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• 제25권4호
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• pp.620-627
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• 2011

We evaluated the hepatoprotective activity of crude hot-water extracts of the traditional Korean medicinal herb, Phellodendri Cortex (PC; Bark of Phellodendron amurense RUPR.), in an experimental model of hepatic damage induced by carbon tetrachloride ($CCl_4$). The serum marker of liver damage, sGOT, sGPT and sALP, were significantly decreased in the liver of the PC treated rats, compared with that of $CCl_4$ treated group. The histological observation of liver section of rats, showed the same protective effect of PC treatment. And the protective activity of PC was more significant in the post-treated group than pre-treated group. The significant decrease of malodialdehyde and increase of glutathion, catalase activity were observed in the liver homogenate of PC treated rats. Based on these findings, it is suggested that PC has potent hepatoprotective effects and the mechanism of the protection may be related to antioxidation pathways.

• 한국작물학회지
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• 제30권1호
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• pp.53-62
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• 1985

Abscisin산(ABA)의 방사면역측정법을 이용하여 발아과정에 있는 수도에 있어서 ABA함량이 어떻게 변동되는가를 구명하였다. 수도종자중에 함유된 ABA함량은 동진벼에 있어서는 76.5ng/g 건물중이었고 삼강벼는 91.1ng/g 건물중이었다. 발아중에 있는 수도의 ABA함량은 종자 침지후 24시간내에 크게 감소되었으며 이와같은 ABA감소율은 침지온도와 발아중 수분흡수율에 유의한 정의 상관관계를 나타냈다. 수도발아중 ABA의 감소는 조직내 ABA가 침지액중으로 일부 용출되고 일부는 조직내에서 다른 화합물로 대사되는 것에 기인함을 알 수 있었다. 수도의 발아는 체내의 함량이 일정수준 이하에서만 일어나며 발아중 ABA함량의 감소율이 수도의 품종간 저온 발아성과도 관련이 있었다.