• 제목/요약/키워드: Microbiological assay

검색결과 264건 처리시간 0.029초

감마선조사 닭고기의 미생물학적 및 유전독성학적 안전성 평가 (Microbiological and Genotoxicological Safety of Gamma-Irradiated Chicken)

  • 곽희진;정차권;강일준
    • 한국식품조리과학회지
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    • 제17권6호
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    • pp.617-624
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    • 2001
  • 계육의 위생화를 위한 방사선 조사기술의 이용가능성을 검토할 목적으로 방사선 조사 계육을 대상으로 미생물학적 및 유전독성학적 안전성 평가를 실시하였다. 3kGy의 감마선 조사는 저온성 세균을 약 1.5 log cycle 정도 감소시킬 수 있었고, 일반세균도 검출한계 이하로 감소되었으며, 특히 7kGy이상의 조사로 모든 오염미생물은 완전히 사멸시킬 수 있었다. 또한 감마선 조사후 냉동저장의 병용은 육제품의 초기살균과 미생물의 생육억제에 매우 효과적임을 알 수 있었다. 유전독성학적 안전성 시험의 경우에는 감마선 조사 및 비조사 닭고기 현탁액의 S. typhimurium TA98, TA100, TA1535 및 TA1537에 대한 복귀변이 집락수를 조사한 결과, 대사활성계 도입 및 부재시 모두, 모든 시험균주에서 시험적용 농도인 0.I~8.3mg/plate의 범위에서 복귀변이 집락수의 농도 의존적인 증가 혹은 감소를 보이지 않아 감마선 조사 닭고기(10kGy)는 돌연변이원성이 없는 것으로 판단되었다. 또한 설치류 망상적혈구를 이용하여 감마선 조사된 닭고기의 염색체 이상 시험을 수행한 결과, 감마선 조사 닭고기는 시험적용 용량인 1250~2500mg/plate의 범위에서 소핵을 가진 망상 적혈구의 출현율이 음성대조군과 유의한 차이를 나타내지 않아 소핵을 유발하지 않음을 확인하여 유전독성학적 측면에서의 안전성이 확인되었다.

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피막 다당류 6B-단백질 복합체를 이용한 폐렴구균에 대한 Multibead Assay의 안정성 향상 (Improvement of the Stability of the Multibead Assay for Pneumococci by the Use of 6B-protein Complex)

  • 김지혜;임낙룡;박문국
    • 미생물학회지
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    • 제39권1호
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    • pp.62-65
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    • 2003
  • 폐렴구균의 혈청형 판별법인 multibead assay에서 사용하는 미세구슬 표면에 코팅한 다당류의 안정성을 높이기 위한 방안을 연구하였다. 폐렴구균 피막 다당류 6B에 bovine serum albumin (BSA)을 결합시킨 다당류-단백질 복합체로 코팅했을 경우와 기존의 방법인 다당류만으로 코팅했을 경우의 코팅 효율과 미세구슬표면에서의 6B 안정성을 비교하였다. 다당류 6B-BSA 복합체를 사용했을 경우에 코팅 효율은 약 200 배 증가하였으며, 미세구슬 표면에서의 6B 안정성도 증가하여, 한번 코팅 후 미세구슬을 사용할 수 있는 기간이 3 일에서 30 일 이상으로 연장될 수 있음을 확인하였다.

미생물정량법에 의한 참돔중의 Tryptophan의 정량 (THE MICROBIOLOGICAL ASSAY OF TRYPTOPHAN IN RED PORGY, PAGROSOMUS MAJOR)

  • 김장양;이현기
    • 한국수산과학회지
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    • 제1권2호
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    • pp.81-86
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    • 1968
  • A porgy was divided into eight parts. After drying at low temperature and pulberizing it, the sample was hydrolyzed by $Ba(OH)_2{\cdot}8H_2O\;at\;120^{\circ}C$, under the pressure of $1\;kg/cm^2$ for 8 hours. Tryptophan was determined by means of microbiological assay, using Lactoba-cillus arabinosus 17-5. The result of experiments was as follows: The content of nitrogen of eight parts of the body amounted $12.55\%$ in muscle being the highest of all, $11.49\%$ in heart, $11.31\%$ in eyeball, $11.22\%$ in liver, $11.06\%$ in intestine, $8.75\%$ in head, $7.81\%$ in gill, and $6.02\%$ in fin which was the lowest of the parts tested. The content of tryptophan per 1 gram nitrogen was 11.79mg in liver, which was the highest of all, 10.11mg in heart, 9.76mg in eyeball, 8.77mg in intestine, 6.28mg in muscle, 5.72mg in head, 4.03mg in gill 2.64mg in fin, and in that order.

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Optimization of Tri-enzyme Extraction Procedures for the Microbiological Assay of Folate in Red Kidney Bean and Roasted Peanut Using Response Surface Methodology

  • Choi, Young-Min;Eitenmiller, Ronald R.;Kim, Seon-Hee;Lee, Jun-Soo
    • Food Science and Biotechnology
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    • 제18권1호
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    • pp.31-35
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    • 2009
  • Total folate content was determined by microbiological assay using Lactobacillus casei spp. rhamnosis (ATCC 7469) with a 96-well microplate technique. Using roasted peanut and red kidney beans as representative legume samples, response surface methodology (RSM) was supplied to optimize the trienzyme procedures for the determination of folate in legumes. After response surface regression (RSREG), the second-order polynomial equation was fitted to the experimental data. Ridge analysis showed that the optimal digestion times were <2 hr for $Pronase^{(R)}$ and $\alpha$-amylase, and <5 hr for conjugase to obtain maximal folate values for legume samples. This study confirms that established digestion times for cereal products (AOAC Method 2004.05) of 3 for protease and 2 hr for $\alpha$-amylase are applicable to legumes. Conjugase treatment can be reduced to 5 from 16 hr and the conjugase level to 5 from 20 mg per sample, providing significant cost saving.

Fast Genetic Variation among Coliphage Quasispecies Revealed by a Random Amplified Polymorphic DNA (RAPD) Analysis

  • Kwon, Oh-Sik;Lee, Jae-Yung
    • Journal of Microbiology
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    • 제34권2호
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    • pp.166-171
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    • 1996
  • Genetic analysis was conducted on newly isolated coliphages form soil by using a RAPD assay. From the initial result, the coliphages were turned out to be different form one another but were closely related to .psi..lambda. due to the fact that they shared the samed RAPD maker in which other T phage testings failed to show. By using the primers EC01 or EC02, a fast genetic mutation of .psi.C1 was found by producing specific RAPD markers on the phages from the first filial progeny to the second filial progeny. When we made a RAPD assay with combined primers (EC01, EC05 and EC08), the genetic mutation was again confirmed in .psi.C1. The assay detection showed mutations in other coliphages such as .psi.C2 and .psi.C3 by revealing specific RAPD bands among different progeny phages, where genetic instability of the coliphages in implied.

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국내식품을 이용한 이유식 개발에 관한 연구(II) - 이유식의 미생물검사와 관능검사 - (Development of the Supplementary Foods for Infants Using Korean Foods - Safety Storage Assay and Sensory Evaluation of the Supplementary Foods for Infants -)

  • 민성희;손경희;윤선
    • 한국식품조리과학회지
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    • 제9권2호
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    • pp.105-108
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    • 1993
  • This study was carried out in order to investigate the condition of storage and to evaluate preference of supplementary foods for infants using Korean foods. Thirty-four different kinds of supplementary foods were developed and fourteen representative ones were selected to be analyzed. A safety storage assay and sensory evaluation were conducted. The results are as follows: 1. In the safety storage assay, the microbiological quality of the products was good during the 13 day-storage in refrigerator. After 14 days, the total plate counts in the products were low and were determined safe. During the 17 day-storage in refrigerator, coliform was not found. 2. In the sensory evaluation, fruit products scored high in acceptability and cow liver products scored low.

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Determination of Carbon Source Utilization of Bacillus and Pythium Species by Biolog$^{(R)}$ Microplate Assay

  • Chun, Se-Chul;R.W. Schneider;Chung, Ill-Min
    • Journal of Microbiology
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    • 제41권3호
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    • pp.252-258
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    • 2003
  • The carbon utilizations of Bacillus species and Pythium species were investigated by using a Biolog$^{(R)}$ microplate assay to determine if there are differences in the carbon utilizations of selected strains of these species. It may be possible to afford a competitive advantage to bacterial biological control agents by providing them with a substrate that they can readily use as a carbon source, for example, in a seed coating formulation. Microplates, identified as SFP, SFN and YT were used to identify spore-forming bacteria, nonspore-forming bacteria, and yeast, respectively. Bacterial and mycelial suspensions were adjusted to turbidities of 0.10 to 0.11 at 600 nm. One hundred microliters of each of the bacterial and mycelial suspension were inoculated into each well of each of the three types of microplates. L-arabinose, D-galactose, D-melezitose and D-melibiose of the 147 carbohydrates tested were found to be utilized only by bacteria, and not by Pythium species, by Biolog$^{(R)}$ microplate assay, and this was confirmed by traditional shake flask culture. Thus, it indicated that the Biolog$^{(R)}$ microplate assay could be readily used to search for specific carbon sources that could be utilized to increase the abilities of bacterial biological control agents to adapt to contrived environments.

Pseudomonas syringae pv. tabaci가 생산하는 tabtoxin의 미생물학적 검색방법에 관한 연구 (Studies on the microbiological assay method for tabtoxin produced in pseudomonas syringae pv. tabaci)

  • 백형석;구재관;전홍기
    • 미생물학회지
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    • 제27권3호
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    • pp.310-315
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    • 1989
  • 식물의 잎에 세균성 정무늬병을 야기시키는 식울 병원성균인 Pseudomonas syringae pv. tuhaci는 tabtoxin 이라는 phytotoxin 을 생성하는데 이 toxin을 미생물학적으로 간편하게 검색하는 방법플 여러가지 지시균주를 사용하여 각족 배지에서 검토하였다. Minimal A agar medium에서는 tabtoxin 검색에 Agrobactcrium tumefaces가 가장 유용한 균주였으며 minimal glucose agar m$\varepsilon$dium 에서도 역시 마찬가시의 견과를 얻였다 Complex agar medium 에서는 사용된 모든 지시균주에 대해 증식저지환이 형성되지 않아, tabtoxin이 생성되지 않음알수 있었다. 배양온도에 따른 tabtox의 생성능은 $20^{\circ}C$$30^{\circ}C$ 에서 최적이였으며 배양시간이 경과함에 따라 tabtoxin 생성량이 증가 하였다. Glutamine을 minimal glucose agar medium에 첨가하여 tabtoxin 에 대한 지시 균주의 반응은 첨 가한 glutamine 의 양이 증가할수록 tabtoxin에 의한 생육억제가 감소함을 알 수 있었다.

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Detection of Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus and Listeria monocytogenes in Kimchi by Multiplex Polymerase Chain Reaction (mPCR)

  • Park, Yeon-Sun;Lee, Sang-Rok;Kim, Young-Gon
    • Journal of Microbiology
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    • 제44권1호
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    • pp.92-97
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    • 2006
  • We developed an mPCR assay for the simultaneous detection, in one tube, of Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus and Listeria monocytogenes using species-specific primers. The mPCR employed the E. coli O157:H7 specific primer Stx2A, Salmonella spp. specific primer Its, S. aureus specific primer Cap8A-B and L. monocytogenes specific primer Hly. Amplification with these primers produced products of 553, 312, 405 and 210 bp, respectively. All PCR products were easily detected by agarose gel electrophoresis, and the sequences of the specific amplicons assessed. Potential pathogenic bacteria, in laboratory-prepared and four commercially available kimchi products, were using this mPCR assay, and the amplicons cloned and sequenced. The results correlated exactly with sequences derived for amplicons obtained during preliminry tests with known organisms. The sensitivity of the assay was determined for the purified pathogen DNAs from four strains. The mPCR detected pathogen DNA at concentrations ranging from approximately 0.45 to $0.05\;pM/{\mu}l$. Thus, this mPCR assay may allow for the rapid, reliable and cost-effective identification of four potentially pathogens present in the mixed bacterial communities of commercially available kimchi.