• 제목/요약/키워드: colony test

검색결과 322건 처리시간 0.023초

Sclerotium rolfsii에의한 잇꽃 흰비단병 (Collar Rot of Safflower Caused by Sclerotium rolfsii)

  • 권진혁
    • 식물병과 농업
    • /
    • 제5권2호
    • /
    • pp.119-121
    • /
    • 1999
  • A destructive collar rot of safflower occurred severely research farm of at Kyongsangnam-do Agricultural Research and Extension Services in 1999. Incidence of the disease at 3 fields in Chinju was ranged from 21.6 to 34.2% Upper parts of infected stems were mostly blighted and white mycelia were found on the lesions. The same fungus was isolated consistently from the infected tissues and confirmed its pathogenecity to safflower. The causal fungus of collar rot disease was identified as Sclerotium rolfsii by the examination of colony type sclerotium formation and pathogenicity test. This fungus also causes stem rot crown rot wilt or blight on the safflower. This is the first report on the collar rot of safflower caused by Sclerotium rolfsii in Korea.

  • PDF

Biological Control of Fusarium Wilt Disease of Pigeonpea

  • Rajesh Singh;B.K. Singh;R.S. Upadhyay;Bharat Rai;Lee, Youn-Su
    • The Plant Pathology Journal
    • /
    • 제18권5호
    • /
    • pp.279-283
    • /
    • 2002
  • Biological control of Fusarium udum causing wilt disease of pigeonpea was studied in vitro, as well as, in vivo. Aspergilluspavus, Anergillus niger, Bacilius licheniformis (strain-2042), Gliocladium virens, Peniciliium citrimum, and Trichoderma harzianum, which were found to be the most potent ones in inhibiting the radial colony growth of the test pathogen, were used as biological control by amending their inocula at diffeyent concentrations in pots and in pathogen-infested soil in the fields. Maximum reduction of the wilt disease was observed with G. vireos both in pots and in the fields. The population of E. udum was found to be markedly reduced when the antagonists were applied in the soil. The study establishes that G. virens can be exploited for the biological control of wilt disease at field level.

Effects of High Relative Humidity on Weight Loss, Color Change, and Microbial Activity of Tomatoes during Refrigerated Storage

  • Pai, Tongkun
    • Journal of Applied Biological Chemistry
    • /
    • 제43권4호
    • /
    • pp.250-253
    • /
    • 2000
  • The effects of high relative humidity (RH) on the physicochemical properties and microbial activity of mature green tomatoes ('Dombito') during refrigerated storage were determined at three temperatures (5, 10, and $15^{\circ}C$) and four different RH levels (91, 94, 97, and 99%). At each temperature, the weight loss rates of tomatoes at different levels of RH were significantly (p<0.05) different from each other. For the samples stored at $10^{\circ}C$, the weight losses were generally higher than those for the samples at $15^{\circ}C$ within the same RH level (i.e., greater vapor pressure deficit). The color change rates ('a' value) showed positive slopes, indicating that the tomato color was changing from green to red. Neither bacteria nor fungi caused visible damages to the samples, and the microbial counts were below 650 colony forming units/$cm^2$ during the test period.

  • PDF

Intention-Oriented Itinerary Recommendation Through Bridging Physical Trajectories and Online Social Networks

  • Meng, Xiangxu;Lin, Xinye;Wang, Xiaodong;Zhou, Xingming
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제6권12호
    • /
    • pp.3197-3218
    • /
    • 2012
  • Compared with traditional itinerary planning, intention-oriented itinerary recommendations can provide more flexible activity planning without requiring the user's predetermined destinations and is especially helpful for those in unfamiliar environments. The rank and classification of points of interest (POI) from location-based social networks (LBSN) are used to indicate different user intentions. The mining of vehicles' physical trajectories can provide exact civil traffic information for path planning. This paper proposes a POI category-based itinerary recommendation framework combining physical trajectories with LBSN. Specifically, a Voronoi graph-based GPS trajectory analysis method is utilized to build traffic information networks, and an ant colony algorithm for multi-object optimization is implemented to locate the most appropriate itineraries. We conduct experiments on datasets from the Foursquare and GeoLife projects. A test of users' satisfaction with the recommended items is also performed. Our results show that the satisfaction level reaches an average of 80%.

Isolation of Cryphonechia parasitica from Cankers on Chestnut Trees in ]Korea

  • Ju, Young-Jik;Kim, Dae-Hyuk;Cha, Byeong-Jin
    • The Plant Pathology Journal
    • /
    • 제18권1호
    • /
    • pp.23-29
    • /
    • 2002
  • A total of 672 Cryphonectria parasitica was isolated from 2,536 blight lesions on chestnut twigs, which were collected from major chestnut plantations all over Korea. Isolation rates of each province ranged from 13.5% in Jeonbuk-ds to 37.4% in Gyeongnam-do, with an average rate of 25.6%. The isolates were classified into six groups according to color and shape of colony on PDA: smooth margin (S), irregular margin (I), yellow to brown (Y), white (W), and white with yellow center (C). Among these groups, IY was the most abundant with an isolation rate of 65%. On the other hand, SW, SC, IW, and SY were quite rare, with isolation rates ranging from 1.5% to 5.8%. When the 672 isolates were inoculated on the chestnut twigs,380 isolates (56.5%) caused lesions larger than the standard virulent isolate EPISS-2, while 158 isolates (23.4%) caused smaller lesions than the standard hypovirulent isolate UEP-1. However, 87.4% of the isolates belonged to the virulent group and only 12.6% belonged to the hypovirulent group based on Bavendamm test. In the provinces of Jeonnam-do, Jeonbuk-do, and Gyeongnamdo, which have high density of chestnut trees, the rates of hypovirulent-like isolates were over 20%.

RT-PCR Targeting rpoB mRNA for Drug Susceptibility Test of Mycobacterium tuberculosis in Liquid Culture

  • Jin, Hyunwoo
    • 대한의생명과학회지
    • /
    • 제22권4호
    • /
    • pp.215-219
    • /
    • 2016
  • The problems of tuberculosis and its drug resistance are very severe. Therefore, rapid and accurate drug susceptibility assay is required. Recently, there has been an increased understanding of the genetic mechanism of Mycobacterium tuberculosis (MTB) drug resistance as well as advancement of molecular technologies. While many gene mutations correlate well with drug resistance, many genes do not show a strong correlation with drug resistance. For this reason, the current study assessed the utility of rpoB mRNA as a target to detect live mycobacteria. In this study, RT-PCR targeting of rpoB mRNA in BCG treated with rifampin was performed. Conventional RT-PCR and real-time PCR targeting rpoB mRNA as well as 85B mRNA was performed to determine whether these two methods could distinguish between viable and non-viable MTB. The levels of rpoB and 85B mRNA detected by RT- PCR were compared in parallel with colony forming unit counts of BCG that were treated with rifampin for different periods of time. The data suggests that that even though both mRNA levels of rpoB and 85B decreased gradually when rifampin-treatment increased, the rpoB mRNA seemed to represent live bacteria better than 85B mRNA. This study clearly indicates that RT-PCR is a good method to monitor viable cell counts in the liquid culture treated with the anti-tuberculosis drug.

기니픽에서 HM10411의 항원성 (Antigenicity of HM10411 in Guinea Pigs)

  • 고우석;김종춘;차신우;김영민;정성엽;권세창;이관순
    • Biomolecules & Therapeutics
    • /
    • 제10권2호
    • /
    • pp.129-135
    • /
    • 2002
  • HM10411 is a recombinant granulocyte-colony stimulating factor (rG-CSF) that has been developing as a drug for neutropenia. In this study, antigenic potential of HM10411 was examined by active systemic anaphylaxis (ASA) in guinea pigs and passive cutaneous anaphylaxis (PCA) in guinea pig-guinea pig system. HM10411 was subcutaneously administered at 0,5, and 50 mg/kg and also as a suspension with adjuvant (50 mg/kg+FCA). Ovalbumin (OVA) as a suspension with adjuvant was used to induce positive control responses. In the ASA test, no symptoms except urination and evacuation that were considered as physiological phenomena were observed at 0 and 5 mg/kg. Two of 5 animals at 50 mg/kg showed sneering, dyspnea, or cyanosis. All animals in the adjuvant mixture group showed severe symptoms of anaphylatic shock and 3 of them died. In the PCA test, no antibody against HM 10411 was detected in the sera from the animals sensitized with 0 or 5 mg/kg. Only 1 serum sample from the animals immunized with 50 mg/kg showed positive reaction against HM10411, while all 5 sera collected from the HM10411 and FCA mixture group contained the HM10411-specific antibodies. These results suggest HM10411 is considered to have antigenicity In guinea pig.

한약 탕전 팩의 미생물 연구 (Observation of Microorganism in Herbal Decoction mafactured by Korean Medical Clinic)

  • 유영법;마진열;하혜경;황대선;김복규;신광수;신현규
    • 대한한의학방제학회지
    • /
    • 제15권2호
    • /
    • pp.119-126
    • /
    • 2007
  • Objectives: This study presents observation of microorganism such as total aerobic bacteria, total fungus, E. coli, Pseudonomas aerugjnosa, Staphylococcus aureus, and Salmonella typhimurium in herbal decoction manufactured by Korean medical clinic. Methods: We examined to observe microorganism using the requirements for the experimental methods recommended by FDA. For the identification, we observed microscopic methods and carried out polymerase chain reaction (PCR) and DNA purification. The purified DNA samples were analyzed by DNA sequencer. As compared with NCBI database. the results were identified by sequences similarity. Results and conclusion: 26 (55%) of 46 decoctions observed positive for microbial test. 12 (46 %) of 26 positive decoctions exceed requirement of microbial limit test. These microbial colony identified genus of Bacillus using microscopic and DNA sequencing methods.

  • PDF

Colorimetric Evaluation of the Time-Killing Assay for Citropin 1.1, Lipopeptide Palm-KK-$NH_2$, and Temporin A

  • Baranska-Rybak, Wioletta;Dawgul, Malgorzata;Bielinska, Sylwia;Kraska, Bartlomiej;Piechowicz, Lidia;Kamysz, Wojciech
    • Journal of Microbiology and Biotechnology
    • /
    • 제21권5호
    • /
    • pp.536-539
    • /
    • 2011
  • Nowadays, there are a number of colorimetric techniques available for the determination of a time killing assay in a manner much easier and faster than those previously more commonly used, which were much more time-consuming and laborious colony counting procedures. Here, an attempt has been made to test the antimicrobial peptides of Citropin 1.1, Palm-KK-$NH_2$, and Temporin A on a reference strain of Staphylococcus aureus using resazurin as the cell viability reagent. Staphylococcus aureus was exposed to the test compounds over varying periods of time and the metabolic activity measured, with a profile of antimicrobial activity then established. The results are in agreement with data from previous literature, thus confirming the relevance of the application of resazurin for the testing of antimicrobial agents.

김으로부터 분리한 방사선 저항성 세균 (Identification of Radiation-Resistant Bacterium Isolated from Dried Laver (Porphyra tenera))

  • 안현주;육홍선;김동호;김성;변명우
    • 한국식품영양과학회지
    • /
    • 제30권1호
    • /
    • pp.193-195
    • /
    • 2001
  • A radiation-resistant bacterium was isolated from gamma irradiated dried laver (Porphyra tenera) and its microbiological characteristics were examined. As a result of resistance test to gamma irradiation, the isolate was survived $10^{3}$ CFU/mL even at 30 kGy and significant shoulder line zone was shown until 20 kGy. The $D_{10}$ value was 11.27 kGy. The isolate was gram-positive, non-motile coccus and catalase-positive. n culture, the red-pigmented smooth colony was observed. The biochemical test in API (analytical profile index) system showed that the isolate fermented glucose and fructose as the carbon source. Therefore, a radiation-resistant bacterium isolated from laver was potentially identified as Micrococcus roseus sp.

  • PDF