scholarly journals The influence of media on the recovery of bacteria from the normal mouse caecum

1982 ◽  
Vol 16 (4) ◽  
pp. 364-368
Author(s):  
J. P. Koopman ◽  
H. M. Kennis
Keyword(s):  
Normal Mouse ◽  
Viable Count ◽  
Potassium Salts ◽  
Lower Yield ◽  
Solid Agar ◽  
The Media ◽  
Agar Media ◽  
Microscopic Count ◽  
Quantitative Recovery

3 diluting fluids and 6 agar media were compared for the culture of caecal micro flora of mice. The efficiency of the media in the growth of caecal bacteria was determined by comparing the quantitative recovery (expressed as percentage of the total microscopic count) from the specimens. Of the diluting fluids saline resulted in a low yield (11·47%). Addition of potassium salts increased the yield (23·25%). A broth medium resulted in the highest recovery (44·44%). The influence of storing the caecal micro flora in 3 different diluting fluids on the yield was studied. In all diluents the viable count of caecal bacteria decreased with time, but did so least in broth medium. 6 solid agar media were tested. When saline was used as the diluting fluid, no significant differences in yields were found with all 6 media. When broth medium was used as diluting fluid and yields up to 60% were obtained, no significant differences were shown between the results with 5 media but one medium resulted in a lower yield (32·59%).

Effect of Abamectin on Fungal Growth and its Efficacy as a Miticide in the Laboratory

2020 ◽  
Author(s):  
Dana Sebestyen ◽  
Gabriel Perez-Gonzalez ◽  
Mrinalini Ghoshal ◽  
Barry Goodell
Keyword(s):  
Fungal Growth ◽  
Recommended Dose ◽  
Effective Control ◽  
Phaeomoniella Chlamydospora ◽  
Trunk Disease ◽  
Solid Agar ◽  
The Media ◽  
Agar Media ◽  
The Common ◽  
Mold Mite

Abamectin was tested for use with solid agar media in the laboratory to eliminate or kill the common mold mite Tyrophagus spp. in fungal cultures of Phaeomoniella chlamydospora (Pch) and Phaeoacremonium minimum (Pmin), two important grape pathogens involved in grapevine trunk disease. Abamectin concentrations tested were at or below the recommended dose for abamectin in greenhouse spray applications (≦625ug/mL) to control mites and determine if: a) fungal growth would be inhibited, and b) mites would be killed or their activity suppressed. Abamectin was added either to the media before autoclaving, or filter-sterilized and added after autoclaving, to test the effects of autoclaving on abamectin efficacy. Streptomycin (100µg/mL) was also added to a set of treatments to determine if this commonly-used antibiotic would impact abamectin efficacy against mites, or have an effect on fungal growth when in combination with abamectin. Filter-sterilized abamectin in the range of 62.5 - 312ug/mL, delivered to the media after it had been autoclaved, provided the most effective control of mites while also showing limited inhibition of fungal growth on solid agar media in the absence of streptomycin. The addition of filter-sterilized streptomycin had no significant effect on fungal growth for Pch, while for Pmin a small but significant reduction in growth with streptomycin occurred at abamectin concentrations above 62.5 ug/ml.

TEM processing procedure for a bacillus organism grown on solid media

1990 ◽  
Vol 48 (3) ◽  
pp. 624-625
Author(s):  
Jane Payne ◽  
Philip Coudron
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Fume Hood ◽  
Vacuum Aspiration ◽  
Solid Media ◽  
Transmission Electron ◽  
Solid Agar ◽  
Processing Procedure ◽  
Agar Media ◽  
Rat Bone

This transmission electron microscopy (TEM) procedure was designed to examine a gram positive spore-forming bacillus in colony on various solid agar media with minimal artifact. Cellular morphology and organization of colonies embedded in Poly/Bed 812 resin (P/B) were studied. It is a modification of procedures used for undecalcified rat bone and Stomatococcus mucilaginosus.Cultures were fixed and processed at room temperature (RT) under a fume hood. Solutions were added with a Pasteur pipet and removed by gentle vacuum aspiration. Other equipment used is shown in Figure 3. Cultures were fixed for 17-18 h in 10-20 ml of RT 2% phosphate buffered glutaraldehyde (422 mosm/KgH2O) within 5 m after removal from the incubator. After 3 (30 m) changes in 0.15 M phosphate buffer (PB = 209-213 mosm/KgH2O, pH 7.39-7.41), colony cut-outs (CCO) were made with a scalpel.

Aeromonas hydrophila in Shellfish Growing Waters: Incidence and Media Evaluation

1989 ◽  
Vol 52 (1) ◽  
pp. 7-12 ◽  
Author(s):  
CARLOS ABEYTA ◽  
STEPHEN D. WEAGANT ◽  
CHARLES A. KAYSNER ◽  
MARLEEN M. WEKELL ◽  
ROBERT F. STOTT ◽  
...  
Keyword(s):  
Aeromonas Hydrophila ◽  
Environmental Samples ◽  
Enterotoxin Production ◽  
Beef Extract ◽  
Solid Agar ◽  
Agar Media

Levels of Aeromonas hydrophila determined for the shellfish growing area of Grays Harbor, Washington, ranged from 3 to 4600/100 g in oysters and from 3 to 2400/100 ml in water. Of isolates tested, 80% produced a hemolysin, a trait reported to correlate with enterotoxin production and pathogenicity. Two enrichment broths, Tryptic Soy Broth with ampicillin (TSBA) and Modified Rimler Shotts Broth (MRSB) were compared in combination with three solid agar media: Rimler Shotts (RS), Peptone Beef Extract Glycogen (PBG), and MacConkey's (MCA) agars. TSBA was far superior to MRSB in isolating this species from the environmental samples tested.

scholarly journals First Report of Xylella fastidiosa on Catharanthus roseus in Brazil

Plant Disease ◽  
1998 ◽  
Vol 82 (6) ◽  
pp. 712-712 ◽  
Author(s):  
B. Ueno ◽  
C. K. Funada ◽  
M. A. Yorinori ◽  
R. P. Leite
Keyword(s):  
Catharanthus Roseus ◽  
Xylella Fastidiosa ◽  
Xylem Sap ◽  
Glass Slide ◽  
Bacterial Cells ◽  
First Report ◽  
Vein Clearing ◽  
The Media ◽  
Agar Media ◽  
The U.S

In 1998, plants of periwinkle (Catharanthus roseus L.) showing small leaves, short internodes, and dieback symptoms were observed in a garden at the Instituto Agronomico do Parana (IAPAR), Londrina, PR, Brazil. Stems of these plants were cut into short sections and the sap extracted from the tissue by squeezing with pliers. The sap was blotted onto a glass slide and examined for the presence of bacteria by light microscopy (×400). Microscopy observations revealed the presence of a large number of slender, rod-shaped bacterial cells. The bacteria present in the stems of periwinkle were isolated on buffered cysteine-yeast extract (BCYE) and periwinkle wilt (PW) agar media. Stems were disinfected in 70% alcohol and cut into short sections, and the sap extracted as described above. The sap was blotted directly onto the media and the plates were incubated at 28°C. Typical colonies of Xylella fastidiosa were observed 10 days after isolation on both media. Indirect immunofluorescence tests with antibody specific to X. fastidiosa and anti-IgG conjugated with tetrametylrhodamine isothiocyanate (TRITC) were carried out with xylem sap of periwinkle stem and the isolated bacteria. In both cases, immunofluorescence tests were positive for X. fastidiosa. These results confirm that periwinkle plants were infected with X. fastidiosa. This is the first report of the association of X. fastidiosa with periwinkle plants in Brazil. However, the symptoms observed for the X. fastidiosa-infected periwinkle plants differed from those described previously in the U.S. (1): those symptoms consisted of marginal chlorosis and occasional vein clearing of leaves and wilting of the plants. Reference: (1) R. E. McCoy et al. Plant Dis. Rep. 62:1022, 1978.

Colony formation by Bact. lactis aerogenes on solid media containing antibacterial agents

1952 ◽  
Vol 215 (1123) ◽  
pp. 565-565
Keyword(s):  
Inoculum Size ◽  
Survival Times ◽  
Fluctuation Test ◽  
Solid Media ◽  
Statistical Variation ◽  
Toxic Concentration ◽  
Solid Agar ◽  
Agar Media ◽  
Different Cultures ◽  
The Given

A study has been made of the formation of colonies of Bact. lactis aerogenes on solid agar media containing antibacterial substances (brilliant green, 1-phenyl semicarbazide, phenyl mercuric nitrate, phenol, thymol and chloramphenicol) at such concentrations that a small fraction only of the inoculated cells develop. The pattern of behaviour varies from drug to drug and sometimes from culture to culture with a given drug. As the toxic concentration increases, colonies diminish in number, in size or in both. Anomalous dependence in some cases upon inoculum size, and the appearance in others of satellites to the main colonies, indicate the operation of co-operative effects probably depending upon diffusion of metabolites or antagonists. The statistical variation in the number of developing colonies is greater for different cultures than for samples of a given culture (as in the well-known fluctuation test for mutations), but the behaviour of a culture may depend upon the aeration, and upon the precise conditions of the test. The variances show no apparent relation to the ease of production of resistance to the given drug. Nor does the scatter of the survival times in liquid media containing phenol (no resistance developable) differ much from that in chloramphenicol (resistant forms readily produced). Consideration of the factors determining the successful formation of a colony on a drug plate suggests that the fluctuation test for the demonstration of mutations must be applied with great reserve.

Automated Detection of Hydrogen Sulfide Release from Thiosulfate by Salmonella spp.

1998 ◽  
Vol 61 (5) ◽  
pp. 620-622 ◽  
Author(s):  
LEORA A. SHELEF ◽  
WEI TAN
Keyword(s):  
Hydrogen Sulfide ◽  
Ammonium Citrate ◽  
Ferric Ammonium Citrate ◽  
Decarboxylase Activity ◽  
Salmonella Spp ◽  
Sharp Drop ◽  
Conventional Tests ◽  
Ferric Ammonium ◽  
The Media ◽  
Agar Media

Hydrogen sulfide production is used in conventional tests for identification and differentiation of Salmonella spp. from other species of Enterobacteriaceae, and a black precipitate on agar media is the indicator of the reaction. Selective liquid media were formulated for automated optical detection of H2S in salmonellae using the BioSys instrument. The media contained thiosulfate and ferric ammonium citrate, and production of H2S caused copious black pigmentation of the broth. Combination of the H2S indicators with dulcitol or xylose as fermentable carbohydrate, lysine, omithine or arginine to induce decarboxylase activity, and Tergitol 4 as inhibitor selectively identified six Salmonella spp. by a sharp drop in transmittance at 585 nm. The time for detection of transmittance changes was inversely proportional to initial numbers of CFU in the media: 10 h for 105 CFU/ml and 17 h for 101 CFU/ml. No detection was observed in six non-Salmonella species of Enterobacteriaceae tested.

scholarly journals Germination of spores of Amazonian ferns Polypodium aureum in different culture media

2019 ◽  
Vol 25 (3) ◽  
pp. 218-224
Author(s):  
Patrícia Aparecida Santos Alves ◽  
Alline Mendes Alves ◽  
William Hiroshi Suekane Takata
Keyword(s):  
Culture Media ◽  
Germination Percentage ◽  
Germination Time ◽  
Plant Group ◽  
Germination Speed ◽  
Different Types ◽  
The Media ◽  
Agar Media ◽  
Brazilian Flora ◽  
The Tropics

Abstract The greatest diversity of ferns occurs in the tropics, where approximately three in four of the species are found. In the Brazilian flora, the ferns have megadiversity, being an important plant group. The objective was to evaluate the spores germination of ferns Polypodium aureum in different types of culture medium. The sporangia were removed from fertile fronds and sterilized with sodium hypochlorite 0.57% during 30 minutes. After sterilization, the sporangia were seeded in culture media agar, MS, SH, White and B5. The experimental design was completely randomized being composed of 5 treatments (agar media, B5, SH, White and MS) and 10 replications. The ratings occurred every 3 days over a period of 45 days, counting the number of spores germinated. After this period, the germination percentage, germination time on medium, germination speed index and timing of germination were calculated. The germination percentage and the index of synchronization have not changed in function of different culture media. The medium White presented the highest average for the germination speed index whereas the agar media, MS, SH and B5 had the same germination speeds. The percentage of mortality was higher in MS medium, the White medium presented the lowest percentage of mortality, and the media composed by agar, SH and B5 showed intermediate values. The lowest average germination time occurred at the media SH and B5, since the environment composed by agar showed higher average germination time. The media MS and White showed similar results to the agar, SH and B5. Based on the obtained results, it can be concluded that the White medium is the most effective on the germination of spores of Polypodium aureum.

Comparison of Media for Isolation of Bacillus cereus from Foods

1985 ◽  
Vol 48 (11) ◽  
pp. 969-970 ◽  
Author(s):  
MATS PETERZ ◽  
CHRISTER WIBERG ◽  
PER NORBERG
Keyword(s):  
Bacillus Cereus ◽  
Egg Yolk ◽  
Food Products ◽  
Bromothymol Blue ◽  
Blood Agar ◽  
The Media ◽  
Dry Food ◽  
Better Than ◽  
Quantitative Recovery

Three media for isolation of Bacillus cereus from foods were compared: mannitol-egg yolk-polymyxin (MYP) agar, polymyxin pyruvate-egg yolk-mannitol-bromothymol blue agar (PEMBA) and non-selective blood agar. Twenty-six of 45 samples of different reconstituted and incubated dry food products and 18 of 29 samples of milk and cream (incubated overnight) contained B. cereus. None of the media performed significantly better than the others as regards quantitative recovery or selectivity.

scholarly journals Effects of inositol starvation on the levels of inositol phosphates and inositol lipids in Neurospora crassa

1993 ◽  
Vol 292 (3) ◽  
pp. 805-811 ◽  
Author(s):  
P L Lakin-Thomas
Keyword(s):  
Neurospora Crassa ◽  
Phytic Acid ◽  
Inositol Phosphates ◽  
Acid Synthesis ◽  
Extracellular Medium ◽  
Absolute Requirement ◽  
Solid Agar ◽  
Inositol Lipids ◽  
Agar Media ◽  
High Concentrations

An inositol-requiring strain of Neurospora crassa was labelled during growth in liquid medium with [3H]inositol, and the levels of inositol phosphates and phosphoinositides were determined under inositol-sufficient and inositol-starved conditions. Because the mutant has an absolute requirement for inositol, the total mass of inositol-containing compounds could be determined. Inositol-containing lipids were identified by deacylation and co-migration with standards on h.p.l.c.; PtdIns3P, PtdIns4P, and PtdIns(4,5)P2 were found in approximately equal amounts, in addition to large amounts of PtdIns. Inositol starvation decreased the level of PtdIns to 10% of the sufficient level, and decreased the levels of the other phosphoinositides to about 25%. A number of inositol phosphates were found, including several InsP3s, InsP4s and InsP5s and phytic acid. Ins(1,4,5)P3 was identified by co-migration with standards on h.p.l.c. and by digestion with inositol phosphomonoesterase. High concentrations of all inositol phosphates were found in the extracellular medium in inositol-starved cultures. Inositol starvation on both liquid and solid agar media decreased the intracellular levels of some inositol phosphates, but increased the levels of phytic acid and several other inositol phosphates which may be its precursors and/or breakdown products. These results may indicate that inositol starvation induces phytic acid synthesis as a protection against the free-radical production and lipid peroxidation characteristic of inositol-less death.

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