• 대한수학회지
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• 제41권4호
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• pp.591-615
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• 2004

In this paper, we provide the algebraic foundations to the theory of relative $\ell$$_1$ homology. In particular, we prove that $\ell$$_1$ homology of topological spaces, both for the absolute case and for the relative case, depends only on their fundamental groups. We also provide a .proof of Gromov's Equivalence theorem for $\ell$$_1$ homology, stated by Gromov without proof [4].

• 한국식품영양과학회지
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• 제31권4호
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• pp.583-588
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• 2002

비지로부터 두 균주를 순수분리하여 동정한 결과 Ent. faecium LL과 L. rhmnosus LS로 확인되었다. 분리된 균을 대두 미세분말용액에서 발효정도를 알아보기 위하여 pH, 산도, 생균수 및 유기산 함량을 측정하였다 Ent. faecium LL은 대두미세분말 용액에서 발효시 pH 4.9, 산도 0.38%, 생균수 1.8$\times$$10^{9}$ CFU/$m\ell$로 젖산생성 및 높은 생균수를 나타내었다. L. rhamnosus LS는 대두미세분말 용액에서는 4.6$\times$$10^{8}$ CFU/mL의 생균수를 나타냈지만 젖산의 생성은 매우 미흡하였다. 그러나 대두미세분말 용액에 당을 첨가하거나 skim milk를 첨가할때 산생성이 급격히 증가되었다. 대두미세분말과 skim milk 4 : 1 혼합액에서 Ent. faecium LL과 L. rhamnosus LS에 의한 젖산발효는 37$^{\circ}C$에서 20시간 안에 curd를 형성하였으며, 각각 0.33% 및 0.77%의 산도와 $10^{8}$ ~$10^{9}$ CFU/$m\ell$정도의 생균수를 보였다. HPLC 분석에서 생성된 젖산의 농도는 L. rhamnosus LS가 600 mg%로 Ent. faecium LL의 350 mg%보다 높았다.

• KSBB Journal
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• 제21권5호
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• pp.376-383
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• 2006

솔잎착즙액(PNE)은 엽록소 함유량(40.8 mg/100 g)이 높고 비타민 C도 다량함유(149 mg/100 g)하고 있어 기능성 식품으로 개발가능성이 높으며, 솔잎 발효액은 향미가 좋아지고 기능성이 높아져서 고부가가치가 크므로 발효의 조건과 활성도를 조사 분석하여 고기능성 솔잎발효액(SFPE)을 개발하고자 하였다. 솔잎자체발효(SFPE)에 관여하는 균을 발효단계에 따라 분리, 선발하고 동정하였다. GPYA배지에서 발효균을 스크린하여 Pichia galeiformis, Candida boidinii, Pichia species, Candida species1, Candida species2, Candida ooidensis, Saccharomyces cerevisiae, Candida karawaiewii를 선발하였으며, 발효가 진행됨에 따라 2년차에는 Candida boidinii, Candida species2, Candida ooidensis, Saccharomyces cerevisiae가 선발되었고, 3년차에는 Candida species1&2가 선발되어 Candida species2가 우점종으로 나타났다. 그러나 발효 4년차에는 어떤 균도 선발되지 않았다. Candida species2는 Candida ernobii와 99.65%의 homology를 보였다. E. coli, Bacillus subtilis와 Staphylococcus aureus에 대해서 SFPE를 농도별로 처리하였을 때 높은 항균활성을 확인하였다. SFPE 1, 4, 7의 항산화 활성은 $0.025{\mu}{\ell}/ml$의 농도로 처리하였을 경우 SFPE 1, 4, 7이 약 34.8%의 NBT scavenging의 활성을 보여주었고, $0.2{\mu}{\ell}/ml{\sim}0.3{\mu}{\ell}/ml$의 농도에서는 SFPE 1, 4, 7이 약 90%에 달하는 NBT scavenging 의 활성능력을 확인할 수 있었다. 또한 전기생리학적 실험을 통하여 솔잎발효액이 쥐의 혈관수축 이완에 미치는 효과를 분석한 결과 Phenylephrine(PE)($10^6M$)으로 유발된 수축반응에 대해 SFPE를 0.15 mg/ml과 0.3 mg/ml을 첨가하였을 때 혈관이 다시 이완되었으며, ATP 민감성 $K^+$ 채널 억제제인 glibenclamide($10^5M$)을 처리하였을 때 SFPE 7 효과가 나타나지 않은 것으로 보아 SFPE의 혈관 이완작용이 세포막 ATP-민감성 $K^+$ 통로를 활성화시켜 이루어짐을 확인하였다.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.86-86
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• 2003

Research has been in progress for more than a decade to production of useful proteins by genetic modification in cattle. However, the levels of protein production in transgenic cattle have been reported very low. To enhance protein production in transgenic animal, we tried homologous recombination to donor cells for production of transgenic clone cattle through nuclear transfer procedure. Thus, we constructed the two targeting vectors of human thrombopoietin (TPO) at bovine $\beta$-casein locus using homologous recombination with 13.6 kb and 9.6 kb homology. In two targeting vectors, positive selection was through the neomycin resistance gene and negative selection was by the diphtheria toxin (DT). Gene targeting was attempted in bovine embryonic fibroblasts (bEF) and bovine ear skin fibroblasts (bESF). To determine the most appropriate concentration of neomycin for bEF and bESF, G4l8 resistance was confirmed by culturing the cells in various concentrations of the drug and both of the cells were optimally selected at $900 \mu g/ml$ of neomycin. The transfected bEF and bESF by the targeting vectors were colonized efficiently at the ratio of DNA to transfection reagent such as $4 \mu g$:2 ${mu}ell$ and $1 \mu g$:$2 \mu l$. Comparing number of healthy clones from passage 4 to passage 8, bESF (17%) persist in culture for much longer than bEF (6%). The two gene-targeted bESF clones of 30 random-integrated clones with 9.6 kb homology length were confirmed, however, nothing was out of 72 random integration clones with 13.6 kb homology length, The DT also worked more efficiently in clones transfected with the vector of 9.6 kb homology length. Our data suggests that the choice of donor cell for long culture period should be considered to obtain targeted cell clone, and the gene-targeting frequency and the DT working efficiency are dependent on the length of target homology.

• 한국미생물·생명공학회지
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• 제32권2호
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• pp.172-178
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• 2004

본 연구는 배추 무사마귀병의 생물학적 방제를 위해 수행되었다. 배추 무사마귀병균 Plasmodiophora sp외 길항미생물은 낙엽부식토양에서 분리한 350여 종의 토양미생물 중에서 가장 길항력이 높은 방선균 AC-3균주를 이용하였고, AC-3 균주는 16S rDNA 염기서열분석방법으로 Streptomyces sp.로 동정되었다. Streptomyces sp. AC-3은 배양액 $m\ell$당 9.3 units의 chitinase를 생산하였다. 그 결과 배추 무사마귀병균 Plasmodiophora sp.의 배양액에 Streptomyces sp. AC-3을 접종하고 배양하면 Plasmodiophora sp.의 균체가 팽윤되거나 세포벽이 용해된 모습이 관찰되었다. Streptomyces sp. AC-3은 전딘도 배추 무사마귀병이 만연했던 포장에서 재배 시험하기 위해 제형화시키고 유기질비료에 첨가하여 이용하였다. 미생물제제를 첨가하지 많고 제조한 유기질비료(H-1)(대조구)와 미생물제제 첨가하여 제조한 유기질비료(H-2)(처리구)에 의한 포장시험에서 배추의 생육은 재배 40일 까지는 거의 차이를 나타나지 않았으나 재배 60일에는 다소 차이를 나타내었다. 배추의 병 발생율을 조사한 결과 무사마귀병은 H-1 비료 처리구에서는 36.17% 병이 발생되었으나 H-2 비료 처리구에서는 18.28% 발병되어 약 50%의 방제효과를 나타내었으며, 균핵병, 잎마름병, 그루썩음병 등에서도 길항효과를 나타내어 생물학적 방제가 가능한 균주로 확인되었다.

• 한국잠사곤충학회지
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• 제40권2호
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• pp.111-116
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• 1998

To construct transformed Bm5 cells, Autographa californica nuclear polyhedrosis virus (AcNPV)IE1 gene, an immediate early viral gene was firstly used in this study. AcNPV IE1 gene, which shares on 95.3% uncleotide sequence homology with Bombyx mori nuclear polyhedrosis virus (BmNPV) IE1 gene, was isolated and cloned into pBluescript. Neomycin gene from pKO-neo was inserted under the control of the IE1 promoter to yield pAcIE1-neo. The plasmid pAcIE1-neo was transfected into Bm5 or Sf9 cells, and neomycin-resistant cells were selected in TC100 medium containing 10% fetal bovine serum (FBS) and 1 mg/$m\ell$ G418 for two weeks. Individual clones were picked and each was amplified for further characterization. The genomic DNA from neomycin-resistnt cells was isolated and characterized by PCR using AcNPV IE1 gene-specific primers and by Southern blot analysis using neomycin gene probe. We concluded that AcNPV IE1 gene was functional in B. moridrived Bm5 cells as well as Spodaptera frugiperda-derived Sf9 cells to produce stably-transformed insect cells.

• Journal of Periodontal and Implant Science
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• 제30권2호
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• pp.419-429
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• 2000

Prevotella intermedia has been implicated as a potent pathogen in many kinds of periodontal, pulpal and periapical diseases. However, it has been isolated from periodontally healthy adults and from edentulous children as well. The intraspecies heterogeneity of Prevotella intermedia has been demonstrated in early studies and finally Shah & Gharbia confirmed the existence of 2 DNA homology groups and proposed dividing Prevotella intermedia into 2 species, Prevotella intermedia and Prevotella nigrescens. This study was designed to examine the frequency of Prevotella intermedia and Prevotella nigrescens in diseased periodontal pockets and healthy gingival sulcus of Korean people by PCR based on 16s ribosomal DNA sequence. One hundred adults who had adult periodontitis but not taken any periodontal treatment or antibiotics during previous 6 months and 50 adults who had healthy periodontal tissue were selected for this study. The sulcular fluid was collected into VMGA by sterilized paper point and diluted to 1,000 times in anaerobic chamber. $100{\mu}{\ell}$ of sample was cultured in $37^{\circ}C$ for 10 days. Among the bacterial colonies, BPB were selected and cultured in BHI broth and then Prevotella intermedia was identified through Gram staining and biochemical test. Identified Prevotella intermedia was cultured again and centrifuged. DNA was extracted from the pellet using several reagents. PCR was performed by previously designed primer. The results were followed. 1. BPB were isolated from 39 of 100 samples of diseased periodontal pockets(39%). 2. Prevotella intermedia was identified from 24 of 39 BPB samples. 3. Among 24 Prevotella intermedia, 21 were confirmed as Prevotella inter - media(87.5) and 2 were confirmed as Prevotella nigrescens(8.33%). 4. BPB were isolated from 9 of 50 samples of periodontally healthy patients. Among them only two were identified as Prevotella intermedia, that is, one was confirmed as Prevotella intermedia and the other was Prevotella nigrescens.