• 제목/요약/키워드: Modified selective media

검색결과 8건 처리시간 0.027초

Development of Modified Selective Media to Differentiate Cryptococcus Species Complex and its Serotypes using Natural Materials

  • Park, Gyu-Nam;Kim, Hye-Ran;An, Dong-Jun;Chae, Hee-Sun;Chang, Kyung-Soo
    • 대한의생명과학회지
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    • 제23권2호
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    • pp.64-72
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    • 2017
  • The formation of brown colonies due to phenol oxidase activity on classic agar media containing natural material extracts of Helianthus annuus or on medium containing L-3,4-dihydroxyphenylalanine has been used to identify Cryptococcus species complex. In this study, various natural materials were used to develop a modified medium and to identify five major serotypes of Cryptococcus species complex. Serotypes A, D, and A/D were pigmented on medium using Perilla frutescens var. japonica Hara (PerJ agar) after a three-day incubation. Serotypes B and C were pigmented on PerJ agar after four- and five-day incubations, respectively. Growth time and pigmentation of the five serotypes occurred more rapidly on PerJ agar than on the other media. In addition, colony morphology, size, and pigmentation were specific by serotype. In conclusion, PerJ agar should be used in clinic settings to identify Cryptococcus species complex and its serotypes rapidly.

Performance of Self-Manufactured Ion Selective Microelectrode (ISME) for Continuous Monitoring of Ammonia and Nitrate Ions

  • Byun, Im-Gyu
    • 한국환경과학회지
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    • 제21권12호
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    • pp.1449-1454
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    • 2012
  • The ion selective microelectrodes (ISME) have been applied to observe the continuous profiles of NO3-N and NH4-N in bulk solutions or biofilms. In order to evaluate the performance and applicability of ion concentration measuring system, the characteristics, such as slope of calibration curve, detection limit and potentiometric selectivity coefficient were investigated. The slopes of calibration curve showed high degree of correspondence for each target ion concentrations. And the detection limits of nitrate and ammonia ion selective microelectrode were 10-4.7 M and 10-4.4 M, respectively. These ion selective microelectrodes were proved that their own performance could be maintained for 16 days after making. NO3-N and NH4-N selective microelectrodes were also adapted to detect the continuous ion profiles of cilia media packed MLE (Modified Ludzack-Ettinger) process. And the monitored nitrate and ammonia ion profiles with the ion selective microelectrode were stable and well corresponded to the results with conventional ion chromatograph. However, the electric potential was unstable until 8 hr because of the unknown noise. The tip shape and performance of the ion selective microelectrode was stably kept over 2 days continuous monitoring.

Salmonella균(菌) 분리용(分離用) 증균배지(增菌培地)의 비교실험(比較實驗) (A Comparison of three Enrichment Media for Isolating Salmonella)

  • 김영자;이승윤;박기덕;민창홍
    • 대한미생물학회지
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    • 제11권1호
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    • pp.33-48
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    • 1976
  • The practical significance of using a selective enrichment procedure for detecion and enumeration of salmonella is well recognized. There are still various selective enrichment media has been communly used. Early years selenite broth was recomnended as an enrichment media for the isolating of salmonella. Hajna introduced a modified tetrathionate broth and demonstrated the greater efficiency to compare with the previous enrichment media. Raj also described that the new medium called dulcitol selenite enrichment and has been found to be very satisfactory, especially general implication in food poisoning. Authors tried to compare these 3 enrichment media for isolating salmonella. 1. When salmonella strains were inoculated $1{\sim}10^6$ cells per tube to these 3 enrichment media, mostly similar results were obtained between selenite broth and DS broth. In these 2 enrichment broth were showed $10^7/ml-10^8/ml$ cells of all tested salmonella strains. But in the case of TT broth it was found that the growth was $10^3/ml{\sim}10^4/ml$ cells for tested strain. 2. When E. coli, Proteus, Citrobacter were inoculate $10{\sim}10^6$ cells per tube to these 3 enrichment media. It was suggested that DS broth was showed more inhibitory action than that of selenite broth. TT broth showed high inhibition to these 3 organisms tested. 3. It was generally known that the incubation time is influenced to the frequency of salmonella detection. For this tendency, DS broth and selenite broth were showed similar results within 24 hrs to 48hrs incubation to the test. But DS broth showed more inhibitory action to E. coli and Proteus than that of selenite broth. 4. When $1{\sim}10$ cells were inoculated(per tube) to these 3 enrichment media, DS broth was found to be more sensitive than that of selenite broth.

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다양한 식품에서 Campylobacter jejuni 검출을 위한 real-time PCR과 배지배양법의 비교검증 (Comparison of Real-Time PCR and Culture Methods for Detection of Campylobacter jejuni in Various Foods)

  • 천정환;현지연;황인균;곽효선;한정아;김무상;김종현;송광영;서건호
    • 한국식품과학회지
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    • 제43권1호
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    • pp.119-123
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    • 2011
  • 본 연구에서는 두 종류의 선택배지를 활용한 배지배양법과 realtime PCR의 C. jejuni 검출능력을 비교하였다. 소시지, 쇠고기 분쇄육, 무순에 C. jejuni를 접종하고 Hunt broth로 증균배양 하였으며, mCCD agar와 Preston agar에 배양액을 획선도말하여 미호기적으로 배양하였다. 동시에 증균배양액에서 1 mL을 채취하여 realtime PCR을 실시하였다. 실험결과, real-time PCR은 쇠고기 분쇄육과 소세지에서 두 가지 선택배지와 비교하여 동일한 검출력을 보였으나 무순에서는 훨씬 더 많은 양성을 검출하였다(p<0.05). 두 배지간의 비교에서는 Preston agar와 mCCD agar는 통계학적 유의차가 없는 민감도를 보였다(p>0.05). 결론적으로 real-time PCR은 표준검출법인 배지배양법과 비교하여 동등하거나 우수한 민감도를 지닌 신속검출기법인 것으로 사료되며, 배지배양법에 앞서 선별검사로 사용할 경우 시간, 비용, 노동력 절감에 있어서 매우 유효한 방법이 될 것으로 판단된다.

Seed and Root Rots of Ginseng (Panax quinquefolius L) Caused by Cylindrocarpon destructans and Fusarium spp.

  • Reeleder, R.D.;Roy, R.;Capell, B.
    • Journal of Ginseng Research
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    • 제26권3호
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    • pp.151-158
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    • 2002
  • Ginseng (Panax quinquefolius L.) has become one of the most valuable herb crops grown in North America. However, traditional cropping practices are favourable to disease and significant losses due to root disease are common, despite frequent use of fungicides. Seedlots are often contaminated with pathogens, however, little is known about the causes of seed decay and the role of seed pathogens as incitants of root rots. It was shown that both Fusarium spp. and Cylindrocarpon destructans were able to rot seeds and that C. destructans was more virulent than Fusarium spp. on seedling roots. A modified rose bengal agar MRBA) medium (1 g KH$_2$PO$_4$; 0.5 g MgSO$_4$; 50 mg rose bengal; 10 g dextrose; 5 g Bacto peptone; 15 g Bacto agar; 30 mg streptomycin sulfate; 250 mg ampicillin; 10 mg rifampicin; 500mg pentachloronitrobenzene; 500 mg dicloran; and 1 L distilled water) was superior to potato dextrose agar in detecting C. destuctans in diseased roots. Isolation of C. destructans from diseased seedlings arising from seeds sown in replant soil supported the hypothesis that this pathogen is a cause of ginseng replant failure in North America.

지표수 및 해수로부터 Listeria monocytogenes의 분리 및 생존성 (Recovery and Survival of Listeria monocytogenes in Surface and Sea Water)

  • 양주;김도경;강호조
    • 대한수의학회지
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    • 제42권3호
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    • pp.327-333
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    • 2002
  • The study was carried out to examine the distribution and survival rate of Listeria monocytogenes (L monocytogenes) from various source of waters using improved isolation method. In comparision of enrichment media for isolation of L monocytogenes from water, the isolation rate and 50% detection limit of the pathogen were higher in UVM modified Listeria enrichment broth (UVM) than Listeria enrichment broth (LEB). On the other hand, when compared the selective media for isolation of the pathogen from water, the isolation rate was highest in culture at Oxford agar followed by Fraser agar, and LEB agar. In order to improve enrichment method, 100 ml of water samples with 0.1 CFU/ml of L monocytogenes was inoculated into 10 ml of UVM concentrated at 10-fold, and incubated for 24 h at $36^{\circ}C$. Isolated frequency of the pathogens in improved enrichment method completely corresponded with common (filter) method. Of a total mumber of 147 water samples from river, lake and sea, the pathogen was isolated from 1 of 39 (2.6%) river water samples and 1 of 75 (1.3%) sea water samples, but no pathogen was isolated from 33 lake water samples. Serotypes of 2 isolates were identified as type 1. L monocytogenes decreased in number from 7.2-7.4 to 4.2-4.7 log CFU/ml for 1 week poststorage (5 and $20^{\circ}C$), but the pathogens were able to be detected in river and sea water until 8 weeks after storage. However, in tap water, L monocytogenes were decreased to undetectable level after 2 weeks of storage.

Correlationship of Vertical Distribution for Ammonia Ion, Nitrate Ion and Nitrifying Bacteria in a Fixed Bed Nitrifying Biofilm

  • Choi, Gi-Chung;Byun, Im-Gyu
    • 한국환경과학회지
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    • 제21권12호
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    • pp.1455-1462
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    • 2012
  • The vertical distributions of nitrifying bacteria in aerobic fixed biofilm were investigated to evaluate the relationship between nitrification performance and microbial community at different HRT. Fluorescent in situ hybridization (FISH) and portable ion selective microelectrode system were adopted to analyze microbial communities and ions profiles according to the biofilm depth. Cilia media packed MLE (Modified Ludzack-Ettinger) like reactor composed of anoxic, aerobic I/II was operated with synthetic wastewater having COD 200 mg/L and $NH_4{^+}$-N mg/L at HRT of 6 hrs and 4 hrs. Total biofilm thickness of aerobic I, II reactor at 4 hrs condition was over two times than that of 6 hrs condition due to the sufficient substrate supply at 4 hrs condition (6 hrs; aerobic I 380 ${\mu}m$ and II 400 ${\mu}m$, 4 hrs; aerobic I 830 ${\mu}m$ and II 1040 ${\mu}m$). As deepen the biofilm detection point, the ratio of ammonia oxidizing bacteria (AOB) was decreased while the ratio of nitrite oxidizing bacteria (NOB) was maintained similar distribution at both HRT condition. The ratio of AOB was higher at 4 hrs than 6 hrs condition and $NH_4{^+}$-N removal efficiency was also higher at 4 hrs with 89.2% than 65.4% of 6 hrs. However, the ratio of NOB was decreased when HRT was reduced from 6 hrs to 4 hrs and $NO_2{^-}$-N accumulation was observed at 4 hrs condition. Therefore, it is considered that insufficient HRT condition could supply sufficient substrate and enrichment of AOB in all depth of fixed biofilm but cause decrease of NOB and nitrite accumulation.

Isolation and Characterization of an Agarase-Producing Bacterial Strain, Alteromonas sp. GNUM-1, from the West Sea, Korea

  • Kim, Jonghee;Hong, Soon-Kwang
    • Journal of Microbiology and Biotechnology
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    • 제22권12호
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    • pp.1621-1628
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    • 2012
  • The agar-degrading bacterium GNUM-1 was isolated from the brown algal species Sargassum serratifolium, which was obtained from the West Sea of Korea, by using the selective artificial seawater agar plate. The cells were Gram-negative, $0.5-0.6{\mu}m$ wide and $2.0-2.5{\mu}m$ long curved rods with a single polar flagellum, forming nonpigmented, circular, smooth colonies. Cells grew at $20^{\circ}C-37^{\circ}C$, between pH 5.0 and 9.0, and at 1-10% (w/v) NaCl. The DNA G+C content of the GNUM-1 strain was 45.5 mol%. The 16S rRNA sequence of the GNUM-1 was very similar to those of Alteromonas stellipolaris LMG 21861 (99.86% sequence homology) and Alteromonas addita $R10SW13^T$(99.64% sequence homology), which led us to assign it to the genus Alteromonas. It showed positive activities for agarase, amylase, gelatinase, alkaline phosphatase, esterase (C8), lipase (C14), leucine arylamidase, valine arylamidase, ${\alpha}$-chymotrypsin, acid phosphatase, naphthol-AS-BI-phosphohydrolase, ${\alpha}$-galactosidase, ${\beta}$-galactosidase, ${\beta}$-glucosidase, catalase, and urease. It can utilize citrate, malic acid, and trisodium citrate. The major fatty acids were summed feature 3 (21.5%, comprising $C_{16:1}{\omega}7c/iso-C_{15:0}$ 2-OH) and C16:0 (15.04%). On the basis of the variations in many biochemical characteristics, GNUM-1 was considered as unique and thus was named Alteromonas sp. GNUM-1. It produced the highest agarase activity in modified ASW medium containing 0.4% sucrose, but lower activity in rich media despite superior growth, implying that agarase production is tightly regulated and repressed in a rich nutrient condition. The 30 kDa protein with agarase activity was identified by zymography, and this report serves as the very first account of such a protein in the genus Alteromonas.