A β-Glucuronidase–Based Agar Medium for the Differential Detection of the Yeast Debaryomyces hansenii from Foods

2005 ◽  
Vol 68 (4) ◽  
pp. 808-814 ◽  
Author(s):  
MANUEL QUIRÓS ◽  
PETRA WRENT ◽  
MARÍA-JOSÉ VALDERRAMA ◽  
MARÍA-ISABEL de SILÓNIZ ◽  
JOSÉ M. PEINADO
Keyword(s):  
Solid Medium ◽  
Agar Medium ◽  
Debaryomyces Hansenii ◽  
Differential Detection ◽  
Chromogenic Substrate ◽  
Assessment Tests ◽  
Contaminated Food ◽  
Optimal Productivity ◽  
Differential Medium ◽  
Micro Organisms

A selective and differential solid medium, Debaryomyces differential medium (DDM), was used for the isolation of Debaryomyces hansenii. This medium is formulated to allow detection of the β-glucuronidase enzyme using the chromogenic substrate magenta-glucuro.CHA (5Br-6Cl-3indolyl-β-d-glucuronide, cyclohexylammonium salt). Of the more than 120 micro-organisms tested, including yeasts, bacteria, and a filamentous fungus, only D. hansenii produced violet colonies, thus permitting its easy discrimination from other organisms. When quality assessment tests were performed, optimal productivity and selectivity were obtained for D. hansenii. The medium was also satisfactory when used to test naturally contaminated food products.

A Differential Medium for the Isolation of Kluyveromyces marxianus and Kluyveromyces lactis from Dairy Products

1999 ◽  
Vol 62 (2) ◽  
pp. 189-193 ◽  
Author(s):  
MARIA-JOSÉ VALDERRAMA ◽  
M. ISABEL de SILÓNIZ ◽  
PILAR GONZALO ◽  
JOSÉ M. PEINADO
Keyword(s):  
Productivity Growth ◽  
Kluyveromyces Marxianus ◽  
Dairy Products ◽  
Solid Medium ◽  
Kluyveromyces Lactis ◽  
Bacterial Strains ◽  
Dairy Food ◽  
Assessment Tests ◽  
Optimal Values ◽  
Differential Medium

A selective and differential solid medium, called Kluyveromyces Differential Medium (KDM), is described for the isolation of Kluyveromyces marxianus and K. lactis from dairy products. Its discriminative potential is based on the detection of the enzyme β-galactosidase, in the absence of lactose. Of the more than 95 strains tested, including yeasts, bacteria, and filamentous fungus, only the strains of K. marxianus and K. lactis produced blue colonies on the medium due to the presence of X-Gal/IPTG. The bacterial strains were not able to grow in KDM. On this basis, the medium was very satisfactory when testing naturally or experimentally contaminated dairy food products. When quality assessment tests were performed, optimal values of productivity (growth and color) and selectivity were obtained for K. marxianus and K. lactis.

scholarly journals Bismuth sulphite media for the isolation of V. cholerae

1940 ◽  
Vol 40 (5) ◽  
pp. 532-537 ◽  
Author(s):  
W. James Wilson ◽  
L. V. Reilly
Keyword(s):  
Vibrio Cholerae ◽  
Solid Medium ◽  
Agar Medium ◽  
Phenol Red ◽  
Cholera Vibrio ◽  
Enrichment Medium ◽  
The Media ◽  
El Tor

1. A fluid enrichment medium containing sulphite and bismuth based on Read's modification of one of Wilson & Blair's media has been devised and the claims of Read (1939) and Seal (1939) as to the value of such a medium has been confirmed.2. A saccharose mannitol sulphite bismuth alcohol phenol red agar medium is described and has been found to allow rich growth of the true cholera vibrio and to inhibit the growth not only of B. coli and B. lactis aërogenes but of many vibrios liable to be mistaken for the true vibrio cholerae.3. Thirty-one strains of true cholera vibrios, obtained from the National Collection, grew rapidly and profusely in the media.4. Of twenty-five cholera-like and para-cholera strains six grew well, whilst the growth of nineteen was scanty or nil.5. Of eleven El Tor vibrios five grew in both fluid and solid bismuth media, five grew only on the solid medium and in one no growth occurred in either medium. The El Tor colonies were much smaller than those of the epidemic cholera strains.

scholarly journals Selective and differential medium for isolation of Clostridium difficile

1979 ◽  
Vol 9 (2) ◽  
pp. 214-219 ◽  
Author(s):  
W L George ◽  
V L Sutter ◽  
D Citron ◽  
S M Finegold
Keyword(s):  
Clostridium Difficile ◽  
Antimicrobial Agent ◽  
Rapid Method ◽  
Agar Medium ◽  
Egg Yolk ◽  
Blood Agar ◽  
Fluorescent Properties ◽  
Presumptive Identification ◽  
Differential Medium

Clostridium difficile is a recognized cause of pseudomembranous (antimicrobial agent-associated) colitis and may be one of the causes of antimicrobial agent-induced diarrhea. A selective and differential agar medium that contains cycloserine, cefoxitin, fructose, and egg yolk (CCFA) was developed to facilitate the isolation of C. difficile from fecal specimens. Quantitative cultures of 16 stock strains of C. difficile on this medium (and on a medium containing cycloserine, fructose, and egg yolk) yielded counts equivalent to those obtained on blood agar; other media selective for clostridia, including Clostrisel agar, reinforced clostridial agar plus 0.2% para-cresol, and egg yolk-neomycin agar (the latter was inoculated with cultures subjected to prior heat shocking), were also tested and found to be inhibitory to the growth of C. difficile. Of 28 fecal or colostomy effluent specimens cultured on the above media, 14 yielded C. difficile. CCFA was found to be the most sensitive and selective of these media for the recovery of C. difficile. Colonies of C. difficile growing on CCFA had distinctive morphological and fluorescent properties which were sufficient for presumptive identification. CCFA should provide a rapid method for the screening of fecal specimens from patients with antimicrobial agent-associated diarrhea or colitis for C. difficile.

scholarly journals Bio-remedial Effect of Specific Micro-organisms (Bacteria) on Used Engine Oil: A Case Study of Some Mechanic Workshops in Maiduguri Metropolitan Council (MMC)

2020 ◽  
Vol 1 (3) ◽  
Author(s):  
Ibrahim Yerima ◽  
G. A. Felix ◽  
M. I. Ahmad
Keyword(s):  
Zea Mays ◽  
Agar Medium ◽  
Bacterial Species ◽  
Soil Samples ◽  
Engine Oil ◽  
Bacillus Sp ◽  
Used Engine Oil ◽  
Micro Organisms ◽  
Effective Growth

The potential of three micro-organisms (Pseudomonas, Streptococcus and Bacillus sp) were isolated from hydrocarbon contaminated soil and were evaluated for their biodegradation ability. The rate of biodegradation of the engine oil in the soil samples were exposed to used engine oil with different exposure rates of 5,10,15 and 20 years  were studied for a period of three (3) weeks under greenhouse experiment. The soil samples were obtained from four different mechanic workshops in M.M.C and they were plated on nutrients agar and oil agar medium to isolate the bacterial species from the spilled soil samples. All the micro-organisms used in this study showed their abilities to remediate soil exposed to used engine oil and the remediated soil samples were able to support the growth of Maize ( Zea mays) after 10 years  effective growth

scholarly journals Differential agar medium (A7) for identification of Ureaplasma urealyticum (human T mycoplasmas) in primary cultures of clinical material

1976 ◽  
Vol 3 (6) ◽  
pp. 613-625
Author(s):  
M C Shepard ◽  
C D Lunceford
Keyword(s):  
Low Power ◽  
Ureaplasma Urealyticum ◽  
Agar Medium ◽  
Primary Cultures ◽  
Spot Test ◽  
Sensitive Indicator ◽  
Clinical Material ◽  
Clinical Specimens ◽  
Large Colony ◽  
Differential Medium

A differential agar medium for the identification of Ureaplasma urealyticum in primary cultures of clinical specimens is described. The differential medium (no. A7) is specific for the identification of U. urealyticum and other members of the genus Ureaplasma. Large-colony, classical Mycoplasma and Acholeplasma species and Proteus L colonies are unreactive on this differential medium. The medium incorporates the biochemical principle of the direct spot test for urease in colonies of Ureaplasma and contains added urea and a sensitive indicator of ammonia, manganous sulfate. Ureaplasma colonies on this medium are identified as dark golden-brown or rich deep-brown colonies, in sharp contrast to the light background of the medium, when viewed by direct transmitted illumination under the low power of the microscope.

A Chromogenic Medium for the Detection of Yeasts with β-Galactosidase and β-Glucosidase Activities from Intermediate Moisture Foods

2000 ◽  
Vol 63 (5) ◽  
pp. 651-654 ◽  
Author(s):  
M. ISABEL de SILÓNIZ ◽  
MARÍA-JOSÉ VALDERRAMA ◽  
JOSÉ M. PEINADO
Keyword(s):  
Kluyveromyces Marxianus ◽  
Solid Medium ◽  
Debaryomyces Hansenii ◽  
Chromogenic Substrates ◽  
Specific Detection ◽  
Chromogenic Medium ◽  
Dark Blue

A selective and differential solid medium for the specific detection of some common yeasts frequently causing spoilage in intermediate moisture foods is described. The principle of the method is based on the detection of two enzymes, βglucosidase and β-galactosidase, using the chromogenic substrates salmon-Gluc and X-Gal. Over 140 yeasts and bacteria were tested, and Debaryomyces hansenii and Kluyveromyces marxianus strains produced salmon and dark blue colonies, respectively, thus permitting their clear discrimination from other yeasts common in intermediate moisture foods. The medium was very satisfactory when intermediate moisture foods were tested.

Malonate Dulcitol Lysine Iron Agar—A New Differential Medium for the Identification of Salmonella Subgenera I—III

1972 ◽  
Vol 55 (1) ◽  
pp. 214-218
Author(s):  
John R Stroup
Keyword(s):  
Minimal Medium ◽  
Agar Medium ◽  
Decarboxylase Activity ◽  
Lysine Decarboxylase ◽  
Biochemical Tests ◽  
Presumptive Identification ◽  
Differential Medium

Abstract A new differential medium, malonate dulcitol lysine iron agar, containing malonate, dulcitol, L-lysine, and an H2S indicating system has been developed for use at the triple sugar iron agar stage for the identification of Salmonella subgenera I–III. This medium differentiates the subgenera on the basis of the malonate and dulcitol reactions. L-Lysine is incorporated to confirm lysine decarboxylase activity for dulcitol-positive subgenus I cultures. Since it is a near minimal medium, it i? advantageous to inoculate triple sugar iron agar or lysine iron agar slants in parallel with the new medium to act as a source of cells for “O” group serology and to avoid missing aberrant biochemical types. Although a few atypical reactions were noted, all of the 35 typical Salmonella of subgenera I–III tested were typical on malonate dulcitol lysine iron agar medium. Triple sugar iron agar can be considered as giving a presumptive test for Salmonella. However, as it does not differentiate the subgenera, this distinction must be made when the results of in-depth biochemical tests are known. As the subgenera can be differentiated on the basis of malonate and dulcitol reactions, the new medium should allow for the presumptive identification of Salmonella subgenera at least 24 hr earlier than is now possible with conventional procedures.

scholarly journals The recovery of anaerobic bacteria from swabs

1974 ◽  
Vol 72 (3) ◽  
pp. 339-347 ◽  
Author(s):  
J. G. Collee ◽  
B. Watt ◽  
R. Brown ◽  
Sandra Johnstone
Keyword(s):  
Solid Medium ◽  
Standard Sample ◽  
Agar Medium ◽  
Anaerobic Bacteria ◽  
Original Sample ◽  
Progressive Loss ◽  
Apparent Loss ◽  
Oxygen Sensitive ◽  
Wild Strains ◽  
Sampling Procedures

SUMMARYWhen a standard sample of a simulated exudate containing known numbers of anaerobic bacteria was taken up on a swab and plated on solid medium, the number of colonies subsequently cultured represented a very small proportion of the original sample. Evidence is produced that the apparent loss is not primarily attributable to inactivation on the swab but rather to retention of organisms on the swab. This was demonstrable withClostridium welchiiand withBacteroidesspecies that have hitherto been regarded as relatively oxygen-sensitive.When stock strains ofBacteroidesspecies were held for some hours on swabs, some progressive loss of viability was demonstrable. A measure of protection was afforded when these organisms were held aerobically on blood agar medium, but a very exacting anaerobe and some wild strains of faecal anaerobes showed gradual inactivation under these conditions.These findings may have important implications in relation to currently employed bacteriological sampling procedures with swabs in clinical practice.

A COMPARATIVE STUDY OF ASCOSPORE FORMATION BY 43 YEAST CULTURES

1950 ◽  
Vol 28f (11) ◽  
pp. 413-416 ◽  
Author(s):  
A. M. Adams
Keyword(s):  
Comparative Study ◽  
Solid Medium ◽  
Agar Medium ◽  
Comparative Tests ◽  
Yeast Cultures ◽  
Yeast Strains ◽  
Ascospore Formation

In comparative tests for ascospore formation by 43 different yeast strains a solid medium containing acetate and dextrose was shown to be superior to two other sporulation media. Ascospores were formed more frequently and in greater numbers on the former medium. Eleven cultures of the thirty forming ascospores on acetate–dextrose agar yielded 50% or more asci, and seven cultures formed asci only on this agar medium.

scholarly journals REGENERASIRUMPUT LAUT Kappaphycus alvarezii (Doty) MELALUI INDUKSI KALUS DAN EMBRIO DENGAN PENAMBAHAN HORMON PERANGSANG TUMBUH SECARA IN VITRO

2009 ◽  
Vol 4 (1) ◽  
pp. 39
Author(s):  
Emma Suryati ◽  
Sri Rejeki Hesti Mulyaningrum
Keyword(s):  
Acetic Acid ◽  
Growth Regulator ◽  
Culture Medium ◽  
Solid Medium ◽  
Agar Medium ◽  
Kappaphycus Alvarezii ◽  
Indol Acetic Acid ◽  
High Quality Seed ◽  
Medium Culture

Regenerasi rumput laut Kappaphycus alvarezii dilakukan dalam rangka penyediaan benih yang bermutu dan mempunyai keunggulan melalui induksi kalus dan embrio dengan penambahan hormon pertumbuhan yang diintroduksi ke dalam media kultur yang dapat memacu induksi kalus dan penebalan pigmen rumput laut. Media kultur yang digunakan adalah media Conwy padat dengan penambahan agar 0,8%-1,6%. Hormon perangsang tumbuh yang digunakan untuk memacu pertumbuhan kalus dan filamen embrio yaitu IAA (Indol acetic acid), kinetin, dan auxilin dengan konsentrasi berkisar 0,4-1 mg/L. Embrio yang dihasilkan merupakan anakan yang mempunyai sifat yang sama dengan induknya. Sintasan dan perkembangan embrio yang paling baik yaitu dengan penambahan IAA dengan konsentrasi 0,4 mg/L pada media padat. Pembentukan anakan dilakukan dengan mengiris embrio dan menumbuhkan pada media cair yang diperkaya dengan hormon yang sama. Pemeliharaan anakan pada media kultur dilakukan hingga mencapai ukuran 2-3 cm.Regeneration of seaweed Kappaphycus alvarezii was done to provide high quality seed through callus and embryo induction using plant growth regulator which was introducted to the culture medium. This growth regulator can stimulate the callus induction procces and thickening the seaweed pigment. Applied medium culture was agar medium with 0.8%-1.6% concentration enriched with Conwy and the applied growth regulators were IAA (Indol acetic acid), kinetin dan auxilin with 0.4-1 mg/L concentration range. Resulted embryo has the same characteristics with the stock. The best survival rate and embryo growth was IAA treatment with 0.4 mg/L concentration. Formation of embryo was done by transferring them from solid medium to the liquid one with the same growth regulator treatment. The nursery of the seed in culture medium was carried out until it has reached 2-3 cm in size.

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