• 제목/요약/키워드: B2G

검색결과 9,458건 처리시간 0.051초

HPLC에 의한 aflatoxin 분석법에 관한 연구 형광 및 자외선 흡광 검출의 비교 (Determination of Aflatoxins Using High-Performance Liquid Chromatography and Fluorescence or UV Absorbence Detection)

  • 김종규;강회양;민경진
    • 한국환경보건학회지
    • /
    • 제22권1호
    • /
    • pp.36-44
    • /
    • 1996
  • A comparison was made of two detection methods(UV absorbence detection and fluorescence detection with pre-column derivatization, with trifluoroacetic acid) coupled with HPLC for the simultaneous determination of aflatoxin $B_1, B_2, G_1$ and $G_2$. A good separation of the four aflatoxins was achieved on a reversed-phase $C_{18}$ column (30 cm x 3.9 mm) with methanol-acetonitrile-water(20+20+60) for absorbence detection or acetonitrile-water(25+75) for fluorescence detection at the flow rate of 1.0 ml/min. The calibration graphs were linear over the ranges 100 ppb-1 ppm for $B_1/G_1$ and 30~300 ppb for $B_2/G_1$ with absorbence detection, and 1~500 ppb for $B_1/G_1$ and 0.3~150 ppb for $B_2/G_2$ with fluorescence detection. The correlation coefficients were greater than 0.94 and 0.99 for absorbance detection and for fluorescence detection, respectively. The detection limit was 100 ng for $B_1/G_1$ and 30 ng for $B_2/G_2$ with absorbence detection, and 1 ng for $B_1/G_1$ and 0.3 ng for $B_2/G_2$ with fluorescence detection. Recovery rates of aflatoxin $B_1, B_2, G_1$ and $G_2$ added to yeast-extract sucrose broth medium were 66.6%, 59.4%, 67.5% and 59.2%, respectively, for absorbence detection and 82.9%, 71.5%, 80.0% and 69.3%, respectively, for fluorescence detection. The four aflatoxins in culture medium were quantitatively detected by the two methods. The aflatoxins in the rice sample were not detected the absorbence detection method, but were below 10 ppb using the fluorescence detection method. Analysis of aflatoxins by both the absorbence and fluorescence methods coupled with HPLC showed acceptable linearity and good recovery. The absorbence detection was less timeconsuming and safer for treatment. The fluorescence detection was more elective and sensitive though elevated $B_1$ and $G_1$ contents were determined from the TFA-induced conversion of $B_1$ to $B_{2a}$ and $G_1$ to $G_{2a}$.

  • PDF

BINDING NUMBER AND HAMILTONIAN (g, f)-FACTORS IN GRAPHS

  • Cai, Jiansheng;Liu, Guizhen
    • Journal of applied mathematics & informatics
    • /
    • 제25권1_2호
    • /
    • pp.383-388
    • /
    • 2007
  • A (g, f)-factor F of a graph G is Called a Hamiltonian (g, f)-factor if F contains a Hamiltonian cycle. The binding number of G is defined by $bind(G)\;=\;{min}\;\{\;{\frac{{\mid}N_GX{\mid}}{{\mid}X{\mid}}}\;{\mid}\;{\emptyset}\;{\neq}\;X\;{\subset}\;V(G)},\;{N_G(X)\;{\neq}\;V(G)}\;\}$. Let G be a connected graph, and let a and b be integers such that $4\;{\leq}\;a\;<\;b$. Let g, f be positive integer-valued functions defined on V(G) such that $a\;{\leq}\;g(x)\;<\;f(x)\;{\leq}\;b$ for every $x\;{\in}\;V(G)$. In this paper, it is proved that if $bind(G)\;{\geq}\;{\frac{(a+b-5)(n-1)}{(a-2)n-3(a+b-5)},}\;{\nu}(G)\;{\geq}\;{\frac{(a+b-5)^2}{a-2}}$ and for any nonempty independent subset X of V(G), ${\mid}\;N_{G}(X)\;{\mid}\;{\geq}\;{\frac{(b-3)n+(2a+2b-9){\mid}X{\mid}}{a+b-5}}$, then G has a Hamiltonian (g, f)-factor.

HPLC에 의한 aflatoxin 분석법에 관한 연구-형광검출의 최적조건 (Determination of Aflatoxins Using High-Performance Liquid Chromatography with Optimized Fluorescence Detection)

  • 김종규
    • 한국식품위생안전성학회지
    • /
    • 제13권1호
    • /
    • pp.41-46
    • /
    • 1998
  • HPLCdp 의한 주요 afltoxins(aflatoxins $B_1,\;B_2,\;G_1\;및\;G_2$)의 동시 분석에서 postcolumn 유도체화법을 시도하였다. Electrochemical cell (Kobra-cell)을 사용한 postcolumn 유도체화법은 기존의 precolumn 유도체화법보다 분석시간을 단축하였으며 (약 1/2 단축), 더 안전하고 , 향상된 분석능을 보였다. Aflatoxin $B_1과\;G_1의$ 경우 10~100ppb에서, 그리고 B_2와\;G_2의$ 경우 3~30 ppb에서 직선성을 나타내었다. Aflatoxin $B_1과\;G_1은$ 각각 88.9% 및 100.5%로 양호한 회수율을 보였다. Aflatoxin $B_2와\;G_2의$ 경우 분리도는 우수하였으나 회수율에있어서 변이가 크게 나타났다.

  • PDF

한국산 옥수수의 Fumonisin $B_1$$B_2$ 오염현황 (Natural Occurrence of Fumonisins $B_1$ and $B_2$ in Korean Corns)

  • 유춘철;오덕환;박부길
    • 한국식품과학회지
    • /
    • 제31권3호
    • /
    • pp.569-574
    • /
    • 1999
  • 한국산 사료용 옥수수로부터 fumonisin $B_1$$B_2$ 오염 분포 현황을 조사하기 위하여 여러 지역에서 시료를 채취한 후 HPLC의 형광검출기를 이용하여 분석하였다. 분석된 197개 시료 중에서 fumonisin독소의 오염범위와 평균치는 $FB_1$이 72.6%인 143개, $FB_2$는 62.4%인 128개가 오염되었으며 그 범위는 각각 $0{\sim}224.2\;{\mu}g/g$$0{\sim}56.98\;{\mu}g/g$을 나타내었다. 각도별로 생산되는 옥수수의 총 fumonisin오염상황은 143개 시료중 $1\;{\mu}g/g$ 이하의 오염은 15.4%, $10\;{\mu}g/g$ 이상의 오염은 37.5% 그리고 $30\;{\mu}g/g$ 이상의 오염은 14%를 각각 나타내었으며 각도별 $10\;{\mu}g/g$ 이상의 오염율을 살펴보면 강원도가 52.3%로 가장 높았고 경기(45.0%), 전북(40.0%), 충북(26.9%) 및 경북(11.1)의 순으로 나타났다. 또한 각도에서 수집한 옥수수로부터 연도별로 총 fumonisin독소의 농도별 오염현황을 조사한 결과 1996년산이 1995년산에 비하여 $10\;{\mu}g/g$이상 검출된 시료가 더많은 것으로 나타났으며 연도별 평균 fumonisin $B_1$$B_2$의 오염현황은 모두 1995년산이 1996년산에 비하여 현저히 높게 나타났으며 $FB_1$은 1995년도에 분석한 시료에서는 평균 오염수준이 경기, 강원, 전북, 충북 및 경북의 순으로 높게 나타났고 1996년산은 평균 오염수준이 강원, 경북, 전북 및 경기의 순으로 나타났으며 $FB_2$의 경우도 비슷한 경향을 나타내었다.

  • PDF

SHARP CONDITIONS FOR THE EXISTENCE OF AN EVEN [a, b]-FACTOR IN A GRAPH

  • Cho, Eun-Kyung;Hyun, Jong Yoon;O, Suil;Park, Jeong Rye
    • 대한수학회보
    • /
    • 제58권1호
    • /
    • pp.31-46
    • /
    • 2021
  • Let a and b be positive integers, and let V (G), ��(G), and ��2(G) be the vertex set of a graph G, the minimum degree of G, and the minimum degree sum of two non-adjacent vertices in V (G), respectively. An even [a, b]-factor of a graph G is a spanning subgraph H such that for every vertex v ∈ V (G), dH(v) is even and a ≤ dH(v) ≤ b, where dH(v) is the degree of v in H. Matsuda conjectured that if G is an n-vertex 2-edge-connected graph such that $n{\geq}2a+b+{\frac{a^2-3a}{b}}-2$, ��(G) ≥ a, and ${\sigma}_2(G){\geq}{\frac{2an}{a+b}}$, then G has an even [a, b]-factor. In this paper, we provide counterexamples, which are highly connected. Furthermore, we give sharp sufficient conditions for a graph to have an even [a, b]-factor. For even an, we conjecture a lower bound for the largest eigenvalue in an n-vertex graph to have an [a, b]-factor.

Sequencing and Baculovirus-Based Expression of the Glycoprotein B2 Gene of HSV-2 (G)

  • Uh, Hong-Sun;Park, Jong-Kuk;Kang, Hyun;Kim, Soo-Young;Lee, Hyung-Hoan
    • Journal of Microbiology and Biotechnology
    • /
    • 제11권3호
    • /
    • pp.482-490
    • /
    • 2001
  • The gene for glycoprotein B (gB2) of HSV-2-strain G was subcloned, sequenced, recombinated into the lacZ-HcNPV, expressed in insect cells, and compared with the homologous gene of other HSV-2 strains. The ORF of the gB2 gene was 2,715 bp. The overall nucleotide sequence homology of te gB2 gene compared ith that of the two previously reported HSV-2 strains appeared to be over 98%. A recombinant virus named Baculo-gB2 protein in insect cells. The recombination was confirmed by a PCR and the expression was demonstrated by radio immunoprecipitation. Insect cells infected with the Baculo-gB2 virus synthesized and processed gB2 with approximately 120 kDa in the cells, and then secreted it into the culture media, where it reacted with a nomoclonal antibody to gB2. The gB2 polypeptide contained two main hydrophobic regions (a signal sequence from 1 to 23 amino acid residues, and a membrane anchor sequence from aa 745 to 798), eight N-glycosylation sites evenly distributed, and was rich in alanine (11.2%). Antibodies to this recombinant protein that were raised in mice recognized the viral gB2 and neutralized the infectivity of the HSV-2 in vitro. There results show that the gB2 protein was successfully porduced in insect cells and could be used to raise a protective neutralizing antibody. Accordingly, this particular recombinant protein may be useful in the development of a subunit vaccine.

  • PDF

사과, 복숭아, 딸기 품종에 따른 비타민 B1, B2 및 나이아신 함량 비교 (Comparison of Vitamin B1, B2, and Niacin Contents According to the Cultivars of Apple, Peach and Strawberry)

  • 윤성란;류정아;정남혁;장길수;김종수
    • 한국응용과학기술학회지
    • /
    • 제36권4호
    • /
    • pp.1119-1127
    • /
    • 2019
  • 본 연구에서는 다소비 농산물인 사과, 복숭아, 딸기의 품종에 따른 수용성 비타민 B군 중 B1, B2 및 나이아신을 분석하여 함량 차이를 비교하고, 식품성분표의 기초자료로 활용하고자 하였다. 품종에 따른 사과의 비타민 B1 함량은 0.063-0.208 mg/100g, 비타민 B2 함량은 0.006-0.031 mg/100g의 범위의 값으로 검출되었으나, 나이아신은 검출되지 않았다. 품종에 따른 복숭아의 비타민 B1 함량은 0.014-0.276 mg/100g, 비타민 B2 함량은 0.019-0.042 mg/100g, 나이아신 함량은 0.298-1.096 mg/100g 범위의 값으로 검출되었다. 품종에 따른 딸기의 비타민 B1 함량은 0.112-0.394 mg/100g, 비타민 B2 함량은 0.001-0.027 mg/100g, 나이아신 함량은 0.388-0.809 mg/100g 범위의 값으로 검출되었다. 따라서 사과, 복숭아, 딸기 등의 과일의 영양성분 분석 데이터베이스 구축시 품종 요인을 고려할 필요가 있다고 판단된다. 이와 더불어 과일의 수확시기, 재배방법, 환경적인 요인에 따른 차이가 있을 것으로 판단되며 그에 따른 추가적인 연구가 필요하다.

B2B, B2G 환경에서 전자문서의 상호운용을 지원하는 DTD 상호운용 구조의 설계 (Design of Interoperable DTD Architecture supporting Interoperability of Digital Documents for B2B, B2G Environments)

  • 박상윤
    • 경영과정보연구
    • /
    • 제21권
    • /
    • pp.99-114
    • /
    • 2007
  • According as Internet based EC(Electronic Commerce) has been activated, More requirements for exchanging digital documents are being proposed in B2B(Business to Business) and B2G(Business to Government) environments. However, the documents can not be processed automatically, because the structures of documents in each site(companies, central/local governments) do not match. Therefore, W3C(World Wide Web Consortium) has proposed XML(eXtensible Markup Language) DTD(Document Type Declaration) technology to support structuring documents. The XML DTD technology can support interoperability between EC sites. And, XML DTD based documents can be processed automatically in every sites. They will improve efficiency of services in B2B and B2G environments. In this paper, we propose interoperable DTD architecture and IDEP(Interoperable DTD Exchange Protocol) protocol which supports searching DTDs and exchanging DTDs. This technology can popularize DTDs and digital documents.

  • PDF

식·약공용 농산물의 아플라톡신 오염 실태 조사 (A Monitoring of Aflatoxins in Commercial Herbs for Food and Medicine)

  • 김성단;김애경;이현경;이새람;이희진;류회진;이정미;유인실;정권
    • 한국식품위생안전성학회지
    • /
    • 제32권4호
    • /
    • pp.267-274
    • /
    • 2017
  • 2016년 6~12월 서울약령시에서 원형 또는 분말 형태로 유통 판매되는 식 약 공용 농산물 총 62건을 구입하여, 후칼럼 유도체화 장치인 광화학 반응장치를 연결한 HPLC-FLD를 이용하여 아플라톡신($B_1$, $B_2$, $G_1$, $G_2$)을 정성 및 정량 분석함으로써 오염도를 조사하였다. 아플라톡신의 검출한계는 $B_1$ $0.086{\mu}g/kg$, $B_2$ $0.020{\mu}g/kg$, $G_1$ 0.363 g/kg, $G_2$ $0.126{\mu}g/kg$이었고, 정량한계는 $B_1$ $0.262{\mu}g/kg$, $B_2$ $0.059{\mu}g/kg$, $G_1$ 1.101 g/kg, $G_2$ $0.382{\mu}g/kg$였다. 회수율은 $B_1$ 95.1~101.8%, $B_2$ 86.9~105.6%, $G_1$ 95.2~100.6%, $G_2$ 98.6~114.0%이었으며, 변동계수(Coefficient of Variation, %)는 $B_1$ 1.9~9.8%, $B_2$ 1.2~8.2%, $G_1$ 2.1~9.5%, $G_2$ 0.9~9.3%였다. 사용부위에 따른 아플라톡신 오염의 특성을 살펴본 결과 종자(Semen)만 아플라톡신이 검출되었으며, 21건 중 6건(원형 3건, 분말 3건)에서 아플라톡신이 검출되었다. 품목별 아플라톡신 검출 건수를 살펴본 결과, 연자육 중 원형은 7건을 검사한 결과 2건에서 아플라톡신 $B_1$, $B_2$가 검출되었고, 분말은 6건 중 2건에서 아플라톡신 $B_1$이 검출되었다. 산조인 원형은 5건 중 1건에서 아플라톡신 $B_1$, $B_2$가 검출되었으며, 분말은 3건 중 1건에서 아플라톡신 $B_1$, $B_2$가 검출되었다. 아플라톡신 검출량을 살펴보면, 연자육 원형은 총아플라톡신($B_1$, $B_2$, $G_1$$G_2$의 합)이 $ND{\sim}14.655{\mu}g/kg$($B_1$ $ND{\sim}11.869{\mu}g/kg$) 검출되었고, 분말은 총아플라톡신이 $ND{\sim}2.223{\mu}g/kg$($B_1$$ND{\sim}2.223{\mu}g/kg$) 검출되었다. 산조인 원형의 아플라톡신 검출량은 총아플라톡신이 $ND{\sim}9.182{\mu}g/kg$($B_1$$ND{\sim}6.612{\mu}g/kg$) 검출되었고, 분말은 총아플라톡신이 $ND{\sim}21.797{\mu}g/kg$($B_1$$ND{\sim}19.345{\mu}g/kg$) 검출되었다. 따라서 이러한 곰팡이독소 검출현황을 토대로 식 약 공용 농산물에 대한 곰팡이독소 기준을 설정하여 식 약 공용 농산물의 안전한 유통을 관리할 필요가 있다.

MINIMUM DEGREE AND INDEPENDENCE NUMBER FOR THE EXISTENCE OF HAMILTONIAN [a, b]-FACTORS

  • Zhou, Sizhong;Pu, Bingyuan
    • Journal of applied mathematics & informatics
    • /
    • 제28권1_2호
    • /
    • pp.325-331
    • /
    • 2010
  • Let a and b be nonnegative integers with 2 $\leq$ a < b, and let G be a Hamiltonian graph of order n with n > $\frac{(a+b-5)(a+b-3)}{b-2}$. An [a, b]-factor F of G is called a Hamiltonian [a, b]-factor if F contains a Hamiltonian cycle. In this paper, it is proved that G has a Hamiltonian [a, b]-factor if $\delta(G)\;\geq\;\frac{(a-1)n+a+b-3)}{a+b-3}$ and $\delta(G)$ > $\frac{(a-2)n+2{\alpha}(G)-1)}{a+b-4}$.