EFFECT OF ANTIBACTERIAL AGENTS ON THE AUTOPLAQUE PHENOMENON OF PSEUDOMONAS AERUGINOSA

1965 ◽  
Vol 11 (2) ◽  
pp. 213-219 ◽  
Author(s):  
Richard S. Berk
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibacterial Agents ◽  
Agar Medium ◽  
The Other ◽  
Other Hand ◽  
Low Concentrations ◽  
Glucose Agar

A survey of 75 cultures of Pseudomonas aeruginosa containing only one discernible phenotype indicated that 68 routinely exhibited spontaneous lysis, resulting in the appearance of turbid erosions or autoplaques (AP+) when grown on a tryptone–glucose agar medium. Single supplements of non-inhibitory levels of chloromycetin, aureomycin, tetracycline, declomycin, and streptomycin increased the degree of lysis of AP+ strains, but were without effect on AP− strains. Enhancement of lysis was also obtained with sulfadiazine, sulfathiazole, sulfamethoxypyridazine, elkosin, gantrisin, and triple sulfa, while little or no effect was observed with sulfamerizine and thiosulfil. On the other hand, low concentrations of either acriflavine or proflavine retarded the rate and degree of lysis, while single supplements of the active antibiotics overcame the suppressive effects of the dyes.

scholarly journals Effect of temperature on growth of Pseudomonas protegens Pf-5 and Pseudomonas aeruginosa PRD-10 in LB Lennox medium

2018 ◽  
Author(s):  
Wenfa Ng
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Optical Density ◽  
The Other ◽  
Temperature Adaptation ◽  
Effect Of Temperature ◽  
Metabolic Processes ◽  
Two Phase ◽  
Ph Variation ◽  
Temperature Range ◽  
Other Hand

Temperature affects growth of bacteria by influencing enzyme and growth kinetics. Specifically, evolution selects for specific temperature range in which a microbe could thrive, and thus fix the temperature range in which biomolecule structure and function are finely tuned for coping with the thermal conditions prevailing within a cell at a particular temperature. Using aerobic culture in LB Lennox medium in shake flasks, this study aimed to understand the growth of Pseudomonas protegens Pf-5 (ATCC BAA-477) and Pseudomonas aeruginosa PRD-10 (ATCC 15442) at 25, 30 and 37 oC. Experiment results revealed that P. protegens Pf-5 grew very poorly at 37 oC (with maximal optical density of 0.66), while better growth was observed at 25 and 30 oC. Specifically, P. protegens Pf-5 appeared to be better adapted to growth at 25 oC, where the maximal optical density obtained was 5.3 compared to 4.6 at 30 oC. More importantly, two phase growth behaviour was observed during growth at 30 oC where a faster initial phase of growth was followed by a slower one. Growth at 25 and 30 oC exhibited similar pH trend, which suggested similar metabolic processes was activated during growth. On the other hand, P. aeruginosa PRD-10 demonstrated a more efficient conversion of LB Lennox medium into biomass where the maximal optical density obtained at all three growth temperatures were higher than those of P. protegens Pf-5. More importantly, growth of P. aeruginosa PRD-10 exhibited a clear adaptation to growth at 25 and 37 oC, while growth at 30 oC resulted in a lower biomass yield compared to that of 25 and 37 oC. On the other hand, pH variation during culture revealed that P. aeruginosa PRD-10 likely activated similar metabolic processes at all three growth temperatures, where a higher growth temperature would result in the net secretion of more alkaline metabolites. Collectively, P. protegens Pf-5 and P. aeruginosa PRD-10 demonstrated clear temperature adaptation at an evolutionary level. In addition, experiment data suggested that P. aeruginosa PRD-10 might have co-evolved with humans on a substantial time scale resulting in a temperature preference of 37 oC over 30 oC.

Distribution of metallic trace elements (ETM) in surface soils around the Mediouna discharge (southern of Casablanca)

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Trace Elements ◽  
Organic Matter ◽  
Spatial Distribution ◽  
Soil Samples ◽  
The Other ◽  
Surface Soils ◽  
Other Hand ◽  
Metallic Trace Elements ◽  
Low Concentrations ◽  
Uncontrolled Landfill

The objective of present research was to characterize the surface soils located at 300, 600 and 1000 m of an uncontrolled landfill. The work also aims to evaluate the levels and spatial distribution of metallic trace elements (Cd, Pb, Cu, Ni, Zn, Cr, Co and As) in these soils. Soil samples were collected in 36 points around the landfill. Results showed that Cd, Pb, Zn are concentrated in the soils rich in clay and carbonates, and in organic matter, located at 300 m from the landfill. The basic pH of all soils enhances the retention of these metals. On the other hand, As present in soils at 300, 600 and 1000 m at concentrations slightly higher than those of referenced soils were apparently mobilized by water from the solid/water interfaces. The other metals Cu, Ni, Co, Cr are present at very low concentrations.

scholarly journals Evaluation of the use of PetrifilmTM EB count plates for the enumeration of Enterobacteriaceae in poultry samples

2012 ◽  
Vol 32 (3) ◽  
pp. 588-593
Author(s):  
Tainá Drebes ◽  
Cláudia Majolo ◽  
Hans Fröder
Keyword(s):  
Public Health ◽  
Conventional Method ◽  
Food Industry ◽  
The Other ◽  
Other Hand ◽  
Alternative Method ◽  
Significant Difference ◽  
Glucose Agar ◽  
Low Levels ◽  
Conventional Methods

A test that is rapid, simple, accurate, not expensive, gives rapid results, and is sensitive enough to detect low levels of microorganisms would be the most suitable for food industry routine laboratories, or even for a public health laboratories. A ready-to-use alternative, commercially available method is the PetrifilmTM EB method. The aim of this study was to evaluate whether there is a statistically significant difference between the conventional methods based on Violet Red Bile Glucose Agar and the alternative 3M TM Petrifilm (EB) method for the enumeration of Enterobacteriaceae in poultry carcasses. This study also assessed whether the alternative method showed ability to produce results that were directly proportional to the concentration of the target (approximately 270 colony-forming unit.mL-1). A total of 120 poultry carcasses samples showed a significant difference (p < 0.05) between the populations obtained by the two methods, and the conventional method showed low proportionality between the dilutions. On the other hand, the PetrifilmTM EB quantification system showed the capacity to produce results that are proportional to the concentration of the analyte in samples in the concentration range from 1 to 256 colony-forming unit.mL-1.

Analysis of Burmese and Thai Rubies by PIXE

1988 ◽  
Vol 42 (1) ◽  
pp. 44-48 ◽  
Author(s):  
S. M. Tang ◽  
S. H. Tang ◽  
T. S. Tay ◽  
A. T. Retty
Keyword(s):  
Trace Element ◽  
Trace Element Analysis ◽  
The Other ◽  
Element Analysis ◽  
X Ray ◽  
Other Hand ◽  
Low Concentrations

Trace element analysis of 60 Burmese and Thai rubies by using the technique of proton-induced x-ray emission was carried out. It was found that the Burmese rubies contained higher concentrations of all impurities except iron. Our results also reveal that vanadium and iron are useful indicators for Burmese and Thai ruby attribution. The Thai rubies have high contents of iron and very low concentrations of vanadium. On the other hand, all the Burmese rubies examined contain significant amounts of vanadium, and their iron contents are, on the average, four times lower than those in the Thai rubies.

scholarly journals Effect of temperature on growth of Pseudomonas protegens Pf-5 and Pseudomonas aeruginosa PRD-10 in LB Lennox medium

2018 ◽  
Author(s):  
Wenfa Ng
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Optical Density ◽  
The Other ◽  
Temperature Adaptation ◽  
Effect Of Temperature ◽  
Metabolic Processes ◽  
Two Phase ◽  
Ph Variation ◽  
Temperature Range ◽  
Other Hand

Temperature affects growth of bacteria by influencing enzyme and growth kinetics. Specifically, evolution selects for specific temperature range in which a microbe could thrive, and thus fix the temperature range in which biomolecule structure and function are finely tuned for coping with the thermal conditions prevailing within a cell at a particular temperature. Using aerobic culture in LB Lennox medium in shake flasks, this study aimed to understand the growth of Pseudomonas protegens Pf-5 (ATCC BAA-477) and Pseudomonas aeruginosa PRD-10 (ATCC 15442) at 25, 30 and 37 oC. Experiment results revealed that P. protegens Pf-5 grew very poorly at 37 oC (with maximal optical density of 0.66), while better growth was observed at 25 and 30 oC. Specifically, P. protegens Pf-5 appeared to be better adapted to growth at 25 oC, where the maximal optical density obtained was 5.3 compared to 4.6 at 30 oC. More importantly, two phase growth behaviour was observed during growth at 30 oC where a faster initial phase of growth was followed by a slower one. Growth at 25 and 30 oC exhibited similar pH trend, which suggested similar metabolic processes was activated during growth. On the other hand, P. aeruginosa PRD-10 demonstrated a more efficient conversion of LB Lennox medium into biomass where the maximal optical density obtained at all three growth temperatures were higher than those of P. protegens Pf-5. More importantly, growth of P. aeruginosa PRD-10 exhibited a clear adaptation to growth at 25 and 37 oC, while growth at 30 oC resulted in a lower biomass yield compared to that of 25 and 37 oC. On the other hand, pH variation during culture revealed that P. aeruginosa PRD-10 likely activated similar metabolic processes at all three growth temperatures, where a higher growth temperature would result in the net secretion of more alkaline metabolites. Collectively, P. protegens Pf-5 and P. aeruginosa PRD-10 demonstrated clear temperature adaptation at an evolutionary level. In addition, experiment data suggested that P. aeruginosa PRD-10 might have co-evolved with humans on a substantial time scale resulting in a temperature preference of 37 oC over 30 oC.

A New Antibacterial Agent: Propolis

2018 ◽  
Vol 1 (1) ◽  
pp. 15
Author(s):  
Özge İn şaatçi ◽  
Necla Yaman Turan
Keyword(s):  
Antibacterial Agent ◽  
Antibacterial Agents ◽  
Daily Life ◽  
Antibacterial Properties ◽  
The Other ◽  
Textile Materials ◽  
Other Hand ◽  
Textile Products

<p class="pre" align="justify">As textile products are being used widely in Daily life, their antibacterial characteristics gain more importance. The necessity of antibacterial agents used due to the importance given to today's health and alternative products provided by natural routes has also revealed the necessity of this context. This work focuses on the usage of propolis as an antibacterial agent. On the other hand, it aims to gather information on the use of propolis for the purpose of giving antibacterial properties to textile materials. </p>

CELLULAR DISINTEGRATION WITH CONCOMITANT RELEASE OF SLIME AND PRODUCTION OF EXTRACELLULAR MANNAN BY PSEUDOMONAS AERUGINOSA: TWO SEPARATE PHENOMENA

1964 ◽  
Vol 10 (3) ◽  
pp. 467-472 ◽  
Author(s):  
K. Jane Carson ◽  
R. G. Eagon
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Membrane ◽  
Cell Walls ◽  
Cell Membranes ◽  
Deoxyribonucleic Acid ◽  
De Novo ◽  
The Other ◽  
Experimental Intervention ◽  
Other Hand ◽  
Extracellular Slime

Pseudomonas aeruginosa strain 64 has previously been demonstrated to produce an extracellular slime material containing deoxyribonucleic acid and mannan as major constituents. Results reported here indicate that the extracellular deoxyribonucleic acid arises spontaneously from an intracellular origin owing to cellular disintegration without experimental intervention. Cellular disintegration occurs between the first and fifth days of cultivation. It is suggested that cellular disintegration may be due to lysogenic and (or) pyocinogenic phenomena.Production of extracellular mannan, on the other hand, was shown to occur during the first 24 hours of cultivation. Mannose, which was demonstrated to be a carbohydrate of the cell membrane, was not present in cells in sufficient quantity to account for total extracellular mannan. Thus, mannan was indicated to be synthesized de novo and excreted into the medium, possibly as a capsular polysaccharide.Glucose and glucosamine were the only two carbohydrates detected in hydrolysates of cell walls of P. aeruginosa strain 64, while mannose was the only carbohydrate detected in cell membranes.

Yersinia enterocolitica: observations on some growth characteristics and response to selective agents

1980 ◽  
Vol 26 (10) ◽  
pp. 1232-1240 ◽  
Author(s):  
D. A. Schiemann
Keyword(s):  
Yersinia Enterocolitica ◽  
Antibacterial Agents ◽  
Agar Medium ◽  
Growth Characteristics ◽  
Selective Isolation ◽  
Potassium Tellurite ◽  
Surface Active Agents ◽  
Low Concentrations ◽  
Selective Agents ◽  
Surface Active

A broth medium which provided for optimum growth of Yersinia enterocolitica was formulated. In this medium Y. enterocolitica grew best at pH 7.6–7.9 and 32 °C with a generation time of 33–39 min depending upon the strain. Examination of various chemicals as potential selective agents in an agar medium showed a high tolerance for surface-active agents, but cetrimide, 4-nitrophenol, potassium tellurite, and sodium azide were inhibitory at very low concentrations. Irgasan was tolerated at concentrations inhibitory to some other Enterobacteriaceae. Minimum inhibitory concentrations for 57 antibacterial agents tested against 18 strains suggested that carbenicillin, novobiocin, and SCE-129 (cefsulodin) might serve as useful agents for selective isolation of Y. enterocolitica.

scholarly journals Lateritization process of peridotites in Siruka, Choiseul, Solomon Islands

2015 ◽  
Vol 3 (2) ◽  
Author(s):  
Christopher V. Sagapoa ◽  
Akira Imai ◽  
Takeyuki Ogata ◽  
Kotaro Yonezu ◽  
Koichiro Watanabe
Keyword(s):  
Solomon Islands ◽  
The Other ◽  
Nickel Laterite ◽  
Serpentinized Peridotite ◽  
Other Hand ◽  
Low Concentrations ◽  
Residual Elements ◽  
Weathering Crusts ◽  
Iron Chromium ◽  
Cobalt And Nickel

The lateritic weathering crusts exposed in Siruka, Choiseul Islands, Solomon Islands, were developed on the expense of serpentinized peridotite underlain by Siruka schists and Voza lavas with a subhorizontal contact. The lateritic profiles consist of three generalized zones: bedrock, saprolitic zone (weathered and decomposed zone) and the limonitic zones. The profiles demonstrate variations in depths and continuity but illustrate mineralogy and geochemical affinity down profile and are analogous to saprolitic nickel laterite deposits. Silica and magnesia in the bed rock and the saprolitic zones have been removed and only the residual elements (iron, chromium, aluminium, manganese, cobalt and nickel) remain in the limonitic zone. These elements are relatively concentrated as a result of the removal of the soluble elements. Nickel is associated with silica and magnesia, as lizardite ormixed gels (garnierite nickel ore) at the weathering fronts. On the other hand, nickel, with generally low concentrations (

Potentiation of the Anti-factor VIII Effect of Thrombin in Plasma by the Plasminolytic Derivatives of Fibrinogen and Fibrin

1973 ◽  
Vol 30 (02) ◽  
pp. 235-247
Author(s):  
S Chandra ◽  
D. C Triantaphyllopoulos
Keyword(s):  
Protective Effect ◽  
Factor Viii ◽  
The Other ◽  
Other Hand ◽  
Low Concentrations ◽  
Derivatives Of ◽  
Native Plasma ◽  
As If ◽  
Oxalated Plasma

SummaryThe activity of factor VIII in mixtures of native plasma or blood with fibrinogen derivatives at concentrations high enough to inhibit prothrombin consumption, is greatly reduced. On the other hand the activity of factor VIII was found normal in similar mixtures of adsorbed native plasma with fibrinogen derivatives, where no generation of thrombin could have taken place. The fibrinogen derivatives increased significantly the inactivating effect of low concentrations of thrombin on the activity of factor VIII of mixtures of adsorbed oxalated plasma with the derivatives. The same inactivating effect was exerted by fibrinogen derivatives heated at 60° C for 15 minutes and by plasmin lysed fibrin. In contradistinction addition of intact fibrinogen or fibrinogen derivatives to heat-defibrinated plasma protected factor VIII from inactivation by thrombin. When both, intact fibrinogen and its derivatives, were added simultaneously at the same concentrations at which they were added singly, the protective effect was intermediate between that exerted by intact fibrinogen and fibrinogen derivatives alone. Under these conditions the fibrinogen derivatives appeared as if they potentiated the inactivating effect of thrombin. Probably by inhibiting the formation of structural fibrin they increased the amount of thrombin, which remained unadsorbed and free to inactivate factor VIII.

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