• 한국식품과학회지
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• 제22권1호
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• pp.26-32
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• 1990

김치발효 지표로서 미생물군집의 특성을 밝히고자 하였다. 군집크기는 Gram염색법에 의한 현미경직접계수에 의하여 측정하였다. 실온$(15^{\circ}C)$에서 김치발효는 Gram양성균군집, 효모군집 그리고 Gram음성균군집이 순서적으로 천이되었다. Gram양성균군집은 김치를 발효시키는 유산균으로 구성되어 있다. 효모군집의 발달은 김치의 악취를 내는 원인이 되며, Gram음성균군집은 악취와 더불어 김치의 연화작용에 관계된다는 사실이 특정적이었다. 그리고, 외관상의 Gram음성균군은 Gram양성균군집 내의 개체군의 노화와 사멸을 평가하는데 이용될 수 있었다. 특히 저온$(5^{\circ}C)$ 김치발효에서는 효모군집과 Gram 음성균군집이 발달되지 않고 Gram양성균군집만이 발달됨을 알았다. 이 사실로부터 숙성된 김치는 Gram양성균군집에 의하여 만들어짐을 의미한다. 따라서 미생물군집의 발달과 크기는 김치발효의 지표로 이용될 수 있고, 또한 김치숙성도를 수십분 내에 예측하는데 중요한 방법이 될 수 있다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1998년도 한국생물과학협회 학술발표대회
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• pp.182.2-182
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• 1998

No Abstract, See Full Text

• Journal of Microbiology and Biotechnology
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• 제22권5호
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• pp.614-621
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• 2012

Silver nanoparticles production by the green chemistry approach was investigated using an isolated marine actinomycetes strain. The isolated strain was identified as Streptomyces albidoflavus based on chemotaxonomic and ribotyping properties. The strain revealed production of silver nanoparticles both extracellular and intracellularly. Surface Plasmon Resonance analysis with the function of time revealed that particle synthesis by this strain is reaction time dependent. The produced particles were spherical shaped and monodispersive in nature and showed a single surface plasmon resonance peak at 410 nm. Size distribution histograms indicated production of 10-40-nm-size nanoparticles with a mean size of 14.5 nm. FT-IR spectra of nanopartilces showed N-H, C-H, and C-N stretching vibrations, denoting the presence of amino acid/peptide compounds on the surface of silver nanoparticles produced by S. albidoflavus. Synthesized nanoparticles revealed a mean negative zeta potential and electrophoretic mobility of -8.5 mV and -0.000066 $cm^2/Vs$, respectively. The nanoparticles produced were proteinaceous compounds as capping agents with -8.5 mV zeta potential and revealed antimicrobial activity against both Gram-negative and -positive bacterial strains. Owing to their small size, these particles have greater impact on industrial application spectra.

• 한국자원식물학회지
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• 제20권6호
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• pp.491-498
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• 2007

It has been hypothesized that efficient exclusion of methylated retrotransposons and repeated DNA region is one of the rapid and cost-effective approaches for comprehensive gene discovery in large genome size of maize. Three kinds of methylation-sensitive restriction enzymes, HapII, MspI and McrBC, were used to identify the restriction frequency of cytosine methylation sites in maize genome. Roughly 60% of total maize genomic DNA was restricted less than 500bp by McrBC, and the most of restricted small size fraction was composed retrotransposon. In order to validate the efficient construction of gene-rich shotgun library, we compare two gene-rich methyl-filtration shotgun libraries using in vivo and in vitro methyl-filtration system. The size selected DNA fraction by Sau3A-McrBC enzyme treated was very stable and has not appeared modification in E. coli, but most insert DNA size of partially digested with Sau3A were decrease less than 500bp by bacterial methylation-modification system. In compare of retroelements portion, A 44.6% of the sequences were retroelement in unmethyl-filtered library, and the most of them was Copia type, such as Prem, Opie and Ji. The portion of retroelement was drastically decreased to 25% and 20% by in vivo and in vitro filtration system, respectively.

• 대한가정학회지
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• 제41권3호
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• pp.45-56
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• 2003

The purpose of this study was to compare the pantyhose labels of domestic products which contain fiber content, size spec., care symbol, performance properties with those of foreign-made ones, in order to propose a desirable model of label description for the domestic products. The results were as follows: 1) There were differences in the fiber content and fiber mixture ratio of pantyhose on the label according to the countries. The pantyhoses made in Korea and Japan were described only fiber name on the label, while the pantyhoses made in U.S.A., Taiwan, and England were described fiber name and percent of fiber mixture ratio in detail on the label. 2) Most of the pantyhose size produced and sold in Korea were same Free size, but the products from other countries (U.S.A., England, Japan, Taiwan) were sold in various sizes. 3) There were differences, according to the countries, in the care symbol and related explanation of pantyhose on the label. The pantyhoses made in Korea and Taiwan were described care symbol only on the label, while the pantyhoses made in other countries were described additional explanation for care as well as care symbol on the label. 4) It was known that, unlike Korea, other countries were developing and marketing various types of functional pantyhose. For example, U.S.A. and England were focusing on appearance and comfort aspects of pantyhose, while Japan and Taiwan were focusing to develop functional pantyhose like anti-bacterial and anti-ultraviolet ray pantyhose.

• Journal of Microbiology and Biotechnology
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• 제17권8호
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• pp.1236-1241
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• 2007

Five fusion proteins between Z domains derived from Staphylococcal Protein A and Green Fluorescent Protein or Human Proinsulin were produced on the periplasm of Escherichia coli. The effects of the molecular weight and amino acid composition of the translocated peptide, culture medium composition, and growth phase of the bacterial culture were analyzed regarding the expression and periplasmic secretion of the recombinant proteins. It was found that secretion was not affected by the size of the translocated peptide (17-42 kDa) and that the highest periplasmic production values were obtained on the exponential phase of growth. Moreover, the highest periplasmic values were obtained in minimal medium, showing the relevance of the culture medium composition on secretion. In silico prediction analysis suggested that with respect to the five proteins used in this study, those that are prone to form ${\alpha}$-helix structures are more translocated to the periplasm.

• 미생물학회지
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• 제47권3호
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• pp.263-267
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• 2011

유전체 지문 분석법은 세균 균주간의 친연성을 판정하는데 유용하다. 그러나 친연성이 낮은 두 균주의 지문 사이에서 우연히 발생하는 DNA 단편 크기의 일치성은 유전형질의 일치성의 해석에 오차를 유발한다. 본 연구는 임의의 두 유전체 지문에서 우연히 DNA 단편의 크기가 일치할 확률을 정량하여, 유전체 지문에 근거한 친연성 해석의 유의성을 고찰하였다. 유전형질 일치성 없이 단편 크기가 일치할 확률은 관찰되는 단편의 수, 관찰 가능한 전체 단편의 수와 크기가 일치하는 단편의 수로부터 계산될 수 있는 함수로 분석되었다. 유의성에 가장 큰 영향을 미치는 독립 매개변수는 전체 단편의 수였으며, 우연한 공통 단편의 수를 10개 미만으로 유지하기 위해서는 약 200개 이상의 단편이 지문에서 관찰될 수 있어야 하는 것으로 계산되었다.

• Environmental Analysis Health and Toxicology
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• 제28권
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• pp.3.1-3.8
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• 2013

Objectives We investigated the genotoxic effects of 40-59 nm silver nanoparticles (Ag-NPs) by bacterial reverse mutation assay (Ames test), in vitro comet assay and micronucleus (MN) assay. In particular, we directly compared the effect of cytochalasin B (cytoB) and rat liver homogenate (S9 mix) in the formation of MN by Ag-NPs. Methods Before testing, we confirmed that Ag-NPs were completely dispersed in the experimental medium by sonication (three times in 1 minute) and filtration ($0.2{\mu}m$ pore size filter), and then we measured their size in a zeta potential analyzer. After that the genotoxicity were measured and especially, S9 mix and with and without cytoB were compared one another in MN assay. Results Ames test using Salmonella typhimurium TA98, TA100, TA1535 and TA1537 strains revealed that Ag-NPs with or without S9 mix did not display a mutagenic effect. The genotoxicity of Ag-NPs was also evaluated in a mammalian cell system using Chinese hamster ovary cells. The results revealed that Ag-NPs stimulated DNA breakage and MN formation with or without S9 mix in a dose-dependent manner (from $0.01{\mu}g/mL$ to $10{\mu}g/mL$). In particular, MN induction was affected by cytoB. Conclusions All of our findings, with the exception of the Ames test results, indicate that Ag-NPs show genotoxic effects in mammalian cell system. In addition, present study suggests the potential error due to use of cytoB in genotoxic test of nanoparticles.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.256-263
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• 2006

In the model legume Medicago truncatula, two mutants, sickle and sunn, exhibit morphologically and genetically distinct hypernodulation phenotypes. However, efforts to isolate the single recessive and single semidominant genes for sickle and sunn, respectively, by map-based cloning have so far been unsuccessful, partly due to the absence of clones that enable walks from linked marker positions. To help resolve these difficulties, a new bacterial artificial chromosome (BAC) library was constructed using BamHI-digested genomic fragments. A total of 23,808 clones were collected from ligation mixtures prepared with double-size-selected high-molecular-weight DNA. The average insert size was 116 kb based on an analysis of 88 randomly selected clones using NotI digestion and pulsed-field gel electrophoresis. About 18.5% of the library clones lacked inserts. The frequency of the BAC clones carrying chloroplast or mitochondrial DNA was 0.98% and 0.03%, respectively. The library represented approximately 4.9 haploid M. truncatula genomes. Hybridization of the BAC clone filters with a $C_{0}t-l$ DNA probe revealed that approximately 37% of the clones likely carried repetitive sequence-enriched DNA. An ordered array of pooled BAC DNA was screened by polymerase chain reactions using 13 sequence-characterized molecular markers that belonged to the eight linkage groups. Except for two markers, one to five positive BAC clones were obtained per marker. Accordingly, the sickle- and sunn-linked BAC clones identified herein will be useful for the isolation of these biotechnologically important genes. The new library will also provide clones that fill the gaps between preexisting BAC contigs, facilitating the physical mapping and genome sequencing of M. truncatula.

• 생태와환경
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• 제41권1호
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• pp.111-115
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• 2008

Direct effects of zooplankton grazing activities on the natural assemblage of bacterioplankton and algae were evaluated at monthly intervals, from June to October of 2000, in the middle part of the River Spree, Germany. We quantified bacterioplankton, algae, zooplankton abundance and measured carbon ingestion rates (CIRs) by zooplankton according to two zooplankton size classes: (i) micro zooplankton (MICZ), ranging in size from 30 to $150{\mu}m$ and including rotifers and nauplii, excluding protozoans and (ii) macrozooplankton (MACZ), larger than $150{\mu}m$ and including cladocerans and copepods. CIRs were measured using natural bacterial and algae communities in the zooplankton density manipulation experiments. Algae biomass (average${\pm}$SD: $377{\pm}306{\mu}gC\;L^{-1}$, n=5) was always higher than bacterial biomass ($36.7{\pm}9.9{\mu}gC\;L^{-1}$, n=5). Total zooplankton biomass varied from 19.8 to $137{\mu}gC\;L^{-1}$. Total mean biomass of zooplankton was $59.9{\pm}52.5{\mu}gC\;L^{-1}$ (average${\pm}$SD, n=5). Average MICZ biomass ($40.2{\pm}47.6{\mu}gC\;L^{-1}$ n=5) was nearly twofold higher than MACZ biomass ($19.6{\pm}20.6{\mu}gC\;L^{-1}$ n=5). Total zooplankton CIRs on algae (average${\pm}$SD: $56.6{\pm}26.4{\mu}gC\;L^{-1}\;day^{-1}$) were $\sim$fourfold higher than that on bacteria $(12.7{\pm}6.0{\mu}gC\;L^{-1}\;day^{-1})$. MICZ CIRs on bacteria $(7.0{\pm}2.8{\mu}gC\;L^{-1}\;day^{-1})$ and algae $(28.6{\pm}20.6{\mu}gC\;L^{-1}\;day^{-1})$ were slightly higher than MACZ CIRs. On average, MICZ accounted for 55.6 and 50.5% of total zooplankton grazing on bacteria and algae, respectively. Considering the MICZ and MACZ CIRs, the relative role of transferring carbon to higher trophic levels were nearly similar between both communities in the lake-river ecosystem.