• Journal of Food Hygiene and Safety
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• v.31 no.3
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• pp.222-225
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• 2016

In this study, the performance of five selective media for coliform bacteria was evaluated. In total, 83 coliform isolates from ready-to-eat food and 21 reference strains were inoculated in five agar media : Chromocult coliform agar (Merck Millipore), HiCrome coliform agar (Sigma), CHROMagar ECC chromogenic media, Brilliance E. coli/coliform selective agar (OXOID), and endo agar (Merck Millipore). Coliform isolates and reference strains were inoculated on the selective media to test media sensitivity and specificity. The tested media showed the following sensitivities for the isolated strains: Chromocult coliforms agar and HiCrome coliform agar, 94%; Brilliance E. coli/coliform selective agar, 93%; CHROMagar ECC chromogenic media, 92%; and endo agar, 74%. In addition, all media showed 100% specificity, except for endo agar (71%). Moreover Chromocult coliform agar and HICrome coliform agar showed high levels recovery. Taken together, these results identified Chromocult coliform agar and HICrome coliform agar as an effective selective medium for coliforms with higher sensitivity and specificity compared to other media tested in this study.

• Mycobiology
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• v.33 no.4
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• pp.215-222
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• 2005

Variability in growth and sporulation of five isolates of Arthrobotrys dactyloides was studied on five agar, 6 bran and 5 grain media. Potato dextrose agar (PDA) supported maximum growth of isolate A, C and E, while growth of isolate Band D was significantly lower on this medium. On Czapek's agar and yeast glucose agar media the differentiation in the isolates in relation to growth was poor than PDA. The other two media showed much poorer differentiation. On Czapek's agar medium, sporulation was recorded in isolate B only, whereas other isolates showed rare sporulation. Among the bran media, pea bran agar medium supported maximum growth of all the isolates except isolate B. Gram and rice bran agar media were next best. However, the growth of isolate B on the gram bran agar medium was more or less equal as other isolates. On pigeon pea bran agar medium, isolate E failed to grow while other isolates recorded poor growth. On lentil bran agar medium, only isolate Band D recorded little growth, whereas other isolates failed to grow. All the isolates recorded good sporulation on bran agar media except pigeon pea and lentil bran agar media. The grain agar media supported moderate to very good growth of all the isolates. In general isolate B remained slow growing on these media except gram grain and sorghum grain agar media on which growth of this isolate was comparable to other isolates. Sporulation in general, was good on all the grain agar media. Among different substrates screened, barley grain and pea bran were found superior to others for mass culture of isolate A of A. dactyloides.

• Mycobiology
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• v.33 no.2
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• pp.118-120
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• 2005

Most commonly occurring predacious fungus Arthrobotrys oligospora showed great variation in size and shape of conidia on some media. The formation of larger conidia was recorded on beef extract and nutrient agar media. The length of conidia in Richard's YPSS, Sabouraud's, PDA and com meal agar media was of medium size while smaller conidia were produced on Czapek's, Jensen's, Martin's medium. Maximum width of conidia was recorded on YPSS medium followed by Sabouraud's medium. The average size of spores on nematode infested com meal agar medium was slightly increased than those on com meal agar medium.

• Journal of Microbiology
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• v.34 no.4
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• pp.384-386
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• 1996

Application of polyacrylamide gel (PAG) instead of agar to solid cultures of Streptomyces spp. was studied. The improved media were prepared by 1) gelling 20 ml of 5% acrylamide in a glass petri dish at room temperature, 2) washing by running water for more than 8 hr to remove residual reaction reagents, 3) drying at 5$0^{\circ}C$ for 12 hr to make a gel film, 4) autoclaving at 121$^{\circ}C$ for 15 min, and 5) swelling gel for about 4 hr by adding sterile liquid medium. In PAG media there were no differences from the observation of morphological characteristics showing during the cellular differentiation on agar media, whereas the ability to utilize carbohydrates differed somewhat from agar media. Agar media thus were little favorable for biochemical tests which the growth was determined depending on the formation of colony, but washed PAG was superior to serve as a solidifying agent.

• Journal of Plant Biology
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• v.6 no.1
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• pp.8-10
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• 1963

LA, Yong Joon (Coll. of Agr., Seoul National Univ.) Condial production of Cercospora beticola Sacc. on tomato juice agar. Kor. Jour. Bot. VI (1):8-10, 1963. Agar media containing various amount of tomato juice were tested to determine the degree of conidial production of Cercospora beticola. Non-sporulating culture on potato dextrose agar readily sporulated on agar media containing various amout of tomato juice 48 hours after transfer. Considerably small amount of sporulation occurred on agar media containing 10% of tomato juice. Sporulation increased considerably on media containing more than 20% of tomato juice; the higher the proportion of tomato juice in a medium, the greater the number of spores produced.

• Korean Journal of Microbiology
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• v.52 no.1
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• pp.25-31
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• 2016

An enterococci selective medium was developed to detect the presence of enterococci for use as a fecal contamination indicator. Among several media which have been known to detect enterococci, the following 9 different kinds of media were selected: Enterococci Confirmatory agar, Azide dextrose agar, Bromocresol-purple azide agar, Esculin bile agar, Citrate azide tween carbonate agar, KF Streptococcus agar, BROLACIN agar, Kanamycin esculin azide agar, and Membrane filter Enterococcus selective agar. Various components from the nine media were mixed to develop a more effective enterococcus selective medium. The newly developed medium named as 'Enterococcus Mixed medium' was more effective than the previous 9 media. Enterococci strains (Enterococcus avium KACC 10788, Enterococcus faecium KACC 11954, Enterococcus saccharolyticus KACC 10783, Enterococcus durans KACC 10787, Enterococcus faecalis KACC 11304, and Enterococcus hirae KACC 10779) and non-enterococci strains (Escherichia coli KACC 10005, Staphylococcus aureus subsp. aureus KACC 10768, and Bacillus subtilis KACC 10111) were used to test the new medium. As a result, the enterococci strains grew well on the Enterococcus Mixed medium whereas the non-enterococci strains did not grow well on it. Additionally, growth of enterococci with freshwater and seawater samples was observed to be good on the Enterococcus Mixed medium. The result of this study confirmed that the Enterococcus Mixed medium was effective in detecting the target enterococci.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.161-165
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• 2007

Cultivation of a biocontrol agent on a certain medium often results in reduced biocontrol efficacy and alters physiological state. In our previous study, Burkholderia gladioli strain B543 with long-term subculture on tryptic soy agar resulted in significantly reduced biocontrol ability against cucumber damping-off caused by P. ultimum. Therefore, we investigated the influence of laboratory culturing media on biocontrol activity and physiological state of Burkholderia gladioli strain B543 by using long-term repeated culture on a certain medium. When isolate B543 were successionally cultured on King's B agar (KBA), tryptic soy agar, nutrient agar (NA), or soil extract agar more than 20 times, the isolate cultured on KBA or NA showed a significantly enhanced biocontrol efficacy and higher population density in the rhizosphere of cucumber compared to that of the others. However, the isolates cultured on KBA more than 20 times showed the lowest production of protease, siderophore, or antifungal substance(s), measured by skim milk agar, Chrome-Azurol-S agar, and potato dextrose agar amended with 10% of the culture filtrate, respectively. Our results suggest that adaptation to proper culturing medium can alter biocontrol ability and physiological state, and we must consider laboratory media in optimizing the use of biocontrol agents.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.241-247
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• 2013

For in vitro minimal-growth conservation of S. sarmentosum, the in vitro shoots with 10 mm length were cultured on Murashige and Skoog's media (MS) containing different levels of agar (0.8, 1.2, 1.6, 2%), Gelrite (0.4, 0.6, 0.8, 1%), ABA (0, 5, 10, $20mg{\cdot}L^{-1}$), and sucrose (2, 3, 6, and 9%) without subculture at $4^{\circ}C$ and $25^{\circ}C$. All media were supplemented with $0.2mg{\cdot}L^{-1}$ BA, agar and Gelrite media, with 5% sucrose, sucrose media, with 1.2% agar, and ABA media, with 5% sucrose and 1.2% agar, respectively. In vitro minimal-growth conservation in room-temperature ($25^{\circ}C$) was effective in the media containing with $10mg{\cdot}L^{-1}$ ABA or 1.6% agar, and the healthy plantlets could be preserved for 10 months without subculture. After 12 months at $4^{\circ}C$, survival rate was 100% in all media. The in vitro minimal-growth conservation in low temperature ($4^{\circ}C$) was effective in the media containing with $10mg{\cdot}L^{-1}$ ABA or 6% sucrose, and the healthy plantlets could be preserved over 18 months without subculture. Especially, long-term conservation using minimal growth of S. sarmentosum was much more efficient in the medium containing high level sucrose at $4^{\circ}C$ compared to others.

• Korean Journal of Plant Tissue Culture
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• v.22 no.1
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• pp.35-39
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• 1995

In order to investigate the effects of gelling agent on rice anther culture, anthers of rice (Japonica cv Daecheongbyeo) were cultured on N$_{6}$ media supplemented with 0.8, 1.2 or 1.6% Junsei agar and 05, 0.4, 0.6, 0.8 or 1.0% Gelrite (Phytagel, Sigma). On Junsei agar media, the frequency of callus induction was decreased in proportion to agar concentration. The frequency of callus induction was more increased as 67.6% and 54.8% in media containing 0.4 and 0.6% Gelrite than in agar media. The frequency of plant regeneration and spontaneous doubled-diploid was directly proportional to Junsei agar and Gelrite concentration. The number of green and spontaneous doubled diploid plant was highest on 0.6% Gelrite medium. In order to optimize the concentration of growth regulators for the callus induction medium containing 0.6% Gelrite, anthers were cultured on N$_{6}$ media supplemented with 2mg/L NAA, 2 mg/L 2,4-D, 1mg/L NAA and 1mg/L 2, 4-D, or 1mg/L NAA, 1mg/L 2,4-D and 0.5mg/L kinetin. The maximum frequency of callus induction and plant regeneration was obtained from the medium supplemented with 2 mg/L NAA and 0.6% Gelrite. In conclusion the induction of embryogenic callus, the frequency of plant regeneration and in vivo chromosome doubling was more effective in Gelrite media than in Junsei agar media.dia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.5
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• pp.764-768
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• 2010

Three different isolation media for Cronobacter sakazakii have been recommended by Korea Food and Drug Administration from 2007. Performance comparison test was carried out between recommended Cronobacter sakazakii isolation medium. Chromogenic Enterobacter sakazakii agar (CESA) and Enterobacter sakazakii agar (ESA) produce more distinctive colonies having characteristic colors and appearance than Violet red bile glucose agar (VRBGA). The sensitivity and specificity of 3 different isolation media was checked. All 3 tested media showed 100% sensitivity when tested with 30 different Cronobacter sakazakii. The CESA and ESA showed 100% specificity when tested with Enterobacteriaceae except Cronobacter sakazakii, However, VRBGA did not show any specificity, showing inadequate selectivity compared to applicable Cronobacter sakazakii isolation medium. Artificially inoculated Cronobacter sakazakii to milk powder was easily recovered with 3 different isolation media and they all showed almost the same recovery activity.