Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Colony Count, Microbial”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,117 records · Page 62Linked to original sources

[Microbial growth in parenteral nutrition. II. Effects of osmolality].

Study on the behaviour of five microorganisms in different formulations of Parenteral Nutrition (PN) different from each other with regard to osmolarity. The organisms investigated were Staphylococcus aureus (ATCC (12600), Bacillus subtilis (ATCC 6051), Pseudomonas aeruginosa (ATCC 9027), Enterobacter cloacae (ATCC 13047) y Candida albicans (LSH 3156 D). It was observed no direct relation between microbial growth and osmolarity in PN. C. albicans showed the best growth in all the formulations tested, followed by E. Cloacae. The number of the other microorganisms is reduced, and in general, except B. subtilis grow or are reduced in a lesser extension when the glucose solutions added are at 30 or 40%.

Bacteria↗

Composite starch-based coatings applied to strawberries (Fragaria ananassa).

Starch-based coatings were used to the extend storage life of strawberries (Fragaria ananassa) stored at 0 degree C and 84.8% relative humidity. Effects of coating formulation (including starch type, plasticizer, lipid and antimicrobial agent) were analysed with respect to fruit quality. Plasticizer addition was necessary for film and coating integrity to avoid pores and cracks. Plasticizer presence reduced weight losses and maintained surface colour of fruits. Amylomaize coatings showed lower water vapour and gas permeabilities and decreased weight losses for longer periods than corn starch ones. Coatings with sorbitol showed lower permeabilities than glycerol ones. Coatings with antimicrobial agents decreased microbial counts, extending storage life of coated fruits by 10 to 14 days in comparison to the control. The addition of 2 g/l sunflower oil to the formulations decreased the water vapour permeability of starch-based films, maintained the surface colour of coated fruits and controlled effectively fruit weight losses during storage. Lipid addition minimized the effects of starch and plasticizer types. Composite starch-based coatings showed selective gas permeability (CO2 higher than O2) which helps to delay senescence of fruits.

Biofilms↗

Quantifying uncertainty associated with microbial count data: a Bayesian approach.

We consider the problem of estimating bacterial concentration in a substance, given microbial count data. A Bayesian approach is proposed which naturally allows the incorporation of both plate-count data and extra information from confirmatory tests such as genotyping by polymerase chain reaction (PCR). The estimation methods yield posterior credible regions for bacterial concentration, in contrast to the previous methods, which generally only produce point estimates. The approach is illustrated with specific reference to the enumeration of the food-borne pathogen Escherichia coli O157 by spiral plating, although the methodology can be applied to any bacterium or counting method of interest. The results obtained provide guidance to the experimenter as to the number of confirmatory tests which should be performed, and also suggest that in the initial plate count one should err on the side of including rather than excluding colonies whose genotype seems unclear.

Bayes Theorem↗

An alcohol hand rub containing a synergistic combination of an emollient and preservatives: prolonged activity against transient pathogens.

A new alcohol-based hand antiseptic (Octoxy hand rub) containing a synergistic combination of an emollient (Octoxyglycerine) and preservatives was developed and evaluated for immediate and prolonged activity against transient bacteria. The in vitro and in vivo antimicrobial efficacy was compared with other alcohol hand rubs containing preservative/antimicrobial (Prevacare and Avagard). In vitro evaluation was carried out using a tube-dilution method and a pig-skin model. Rapid and prolonged efficacy in vivo was evaluated against Staphylococcus epidermidis on the hands of volunteers. Octoxy hand rub was 100% effective in rapidly killing pathogens including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium in vitro. In volunteers, all three hand rubs gave a significant reduction in microbial count within 15s. Octoxy hand rub showed significantly higher efficacy against S. aureus and Escherichia coli than Avagard and Prevacare 15 min after application to the pig-skin model, and against S. epidermidis in both the pig-skin model and in volunteers. Use of Octoxy hand rub with broad-spectrum immediate and prolonged antimicrobial activity may be a very effective way of improving hand hygiene without exposing the hands to higher concentrations of antimicrobials.

Administration, Cutaneous↗

Microbial growth inside insulated external walls as an indoor air biocontamination source.

The association between moisture-related microbial growth (mesophilic fungi and bacteria) within insulated exterior walls and microbial concentrations in the indoor air was studied. The studied apartment buildings with precast concrete external walls were situated in a subarctic zone. Actinomycetes in the insulation layer were found to have increased concentrations in the indoor air. The moisture content of the indoor air significantly affected all measurable airborne concentrations.

Actinomycetales↗

Comparison of the microbicidal activities of superoxidized and ozonated water in the disinfection of endoscopes.

The microbicidal activities of superoxidized water (electrolysed strong acid water [ESAW] or electrolysed weak acid water [EWAW]), ozonated water, 0.05% chlorhexidine and 2% glutaraldehyde were tested against seven strains of clinical micro-organism isolates. Following incubation of bacterial suspensions in ESAW and EWAW for 10 s, the number of micro-organisms was reduced below the detection limit. The microbicidal activities of ESAW and EWAW were similar to that of glutaraldehyde, and superior to ozonated water and 0.05% chlorhexidine. The microbicidal activities of ESAW, EWAW and ozonated water were markedly diminished in the presence of albumin. Microbial contamination of upper gastrointestinal endoscopes was detected after 90 endoscopic procedures, but treatment of the endoscope with ESAW, EWAW or ozonated water eradicated the microbes. These results indicate that ESAW and EWAW are effective disinfectants after mechanical cleaning of upper gastrointestinal endoscopes, and can, therefore, be used in the endoscopy unit.

Acids↗

[Soil microbial characters under different vegetation communities in taihang mountain area].

This paper measured the numbers and biomass of soil microbes as well as the soil respiration rate under mixed coniferous--broadleaved forest, mixed coniferous forest, pure coniferous forest, pure deciduous broadleaved forest, shrubs, and bare land in Taihang Mountain area, aimed to evaluate the soil microbial characters under different vegetation communities in this area. The results showed that shrub land had the greatest numbers and biomass of soil microbes, followed by deciduous broadleaved forestland, mixed coniferous--broadleaved forestland, pure coniferous forestland, and bare land. Soil respiration rate had the similar trend. When restoring the vegetations on degraded mountain land, more attention should be paid to the natural restoration capability of forest ecosystems.

China↗

Quality improvement of kosher chilled poultry.

Pathogens like Listeria monocytogenes are of great concern in the poultry industry. Poultry, which are subjected to the kosher slaughtering and koshering process, may introduce even higher risks than conventially slaughtered poultry due to the potential for microbial cross-contamination at several critical points in the koshering line, particularly in the chillers. The effect of Microgard (MIC) and Nisin (NIS) on reducing total microbial counts, inhibiting L. monocytogenes, and prolonging shelf life was evaluated. In this work we applied dips of poultry into solutions of NIS, active against Gram-positive bacteria, and MIC, which is a bacteriocin mixture that retards growth of Gram-negative bacteria, and a mixture of organic acids. These treatments inhibited both inoculated and naturally occurring L. monocytogenes on poultry, and increased shelf life, at 6 C, from 2 to 4 d (end of shelf life was considered when total aerobic counts reached 7 log cfu/g).

Abattoirs↗

Effect of propionate toxicity on methanogen-enriched sludge, Methanobrevibacter smithii, and Methanospirillum hungatii at different pH values.

The effect of propionate toxicity at different pH values (6.5, 7.0, and 8.0) on methanogen-enriched sludge. Methanobrevibacter smithii, and Methanospirillum hungatii was studied. Organisms were grown in Balch medium 3 in Hungate tubes, and toxicity was characterized by a decrease in production of methane and in bacterial numbers. Propionate inhibited bacterial growth and cumulative methane production at concentrations as low as 20 mM. In the absence of propionate, the methanogen-enriched sludge and M. smithii showed better cumulative methane production at pH 6.5 and 7.0 than at pH 8.0. However, in the presence of propionate, these organisms showed better cumulative methane production at pH 8.0. M. hungatii differed in its behavior; the best values of cumulative methane production for this organism occurred at pH 7.0. Bacterial numbers reflected the microbial response to the presence of propionate. The highest counts of methanogenic bacteria were observed at pH 6.5 and 8.0. The numbers of methanogens were affected by the presence of propionate even at concentrations as low as 20 or 30 mM; at propionate concentrations above 80 mM, the methanogen count was affected by at least 2 orders of magnitude. Upon comparison of the responses of the pure cultures and the methanogen-enriched sludge to increasing propionate concentrations, it was found that the sensitivity of the pure cultures was similar to that of the methanogens in the sludge.

Colony Count, Microbial↗

Interaction peculiarities between microbial cenosis and local immunity of periodontium of humans under extreme conditions.

The investigations were directed at finding out the peculiarities of both periodontal microflora and local immunity under extreme conditions (spaceflight, saturation diving, antiorthostatic hypokinesia). The obtained results revealed different kinds of interactions amongst which saturation diving resulted in the most severe decrease of commensale microflora level, decrease of local immunity and appearance of periodontal pathogens.

Adolescent↗

Rapid assessment of the bacteriological quality of raw milk using ATP bioluminescence.

Research was conducted to assess the practical use of an ATP bioluminescence assay to evaluate the bacteriological quality of raw milk. Filtration was used to precondition samples before ATP determination, which was measured in relative light units (RLUs). The Lumac ATP bioluminescence assay results were compared with standard plate counts (SPCs) of samples to estimate the microbial load for 246 raw milk samples that were split and either tested immediately or subjected to two preliminary incubation temperatures, 12.8 and 15.6 degrees C, for 18 h. Linear regression analysis procedures were used to analyze the data. Preincubation treatments were analyzed separately. For all treatments, linear regression coefficients were significantly different from zero (P < 0.01). The R2 values calculated using log10-transformed SPC and log10-transformed RLUs for samples tested immediately and samples preliminarily incubated at 12.8 and 15.6 degrees C were 0.58, 0.78, and 0.80, respectively. The R2 for all samples combined was 0.78. Differences in regressions among treatments were tested using a multiple slope and intercept model. Treatment intercepts and slopes were significantly different (P < 0.01). A linear regression equation was used to predict SPC from ATP values. Comparison of predicted values with actual SPCs indicated that ATP could be useful in predicting SPC in raw milk.

Adenosine Triphosphate↗

Soil microbial counts and identification of culturable bacteria in an extreme by arid zone.

Sixteen samples of two soil cores (about 550 and 180 cm in depth) were drilled at intervals in the lower reach of Heihe river basin (northwest of China) in order to illustrate soil microbial characteristics and diversity of culturable bacteria in an extreme by arid environment. Soil water content, organic matter, total nitrogen, pH, direct cell counts, and culturable microorganism counts were evaluated. The total cell concentration was 19-1120/microg (i.e. 0.19-11.2 x 10(8) per g) soil, the culturable bacteria count being 0.2-10.9 per microg (i.e. 2 x 10(5)-10.9 x 10(6) CFU/g) soil. The number of direct cell counts obtained by 4',6-diamidino-2-phenylindole-staining or the cound of culturable microbes after enrichment with different media were statistically significantly correlated with soil organic matters, total nitrogen content, soil water content and surface vegetation; this partly explained the larger number in the deeper first core than in the shallower one. As part of identification of 228 colonies isolated from the two cores, thirty-two were selected for 16S rDNA amplification, sequencing and molecular identification. These 32 isolates were affiliated to 5 major groups of bacteria: alpha-Proteobacteria, 5-Proteobacteria, gamma-Proteobacteria, the high-G+C G+-bacteria, the low-G+C G- -bacteria, and the Cytophaga-Flexibacter-Bacteroides group. Twenty-eight were rod- or short-rod shaped, which accounted for >87.5% of all species; only 4 of 32 species were cocci (<12.5%).

Bacteria↗

Comparison of traditional and disposable bed baths in critically ill patients.

BACKGROUND: For bedridden patients unable to perform personal hygiene measures because of acute illness or chronic debilitation, the bed bath, with either the traditional basin or, more recently, disposable baths, has long been a measure for improving hygiene and costs. OBJECTIVE: To compare the traditional basin bed bath with a prepackaged disposable bed bath in terms of 4 outcomes: time and quality of bath, microbial counts on the skin, nurses' satisfaction, and costs. METHODS: Forty patients in surgical, medical, or cardiothoracic intensive care units received both types of bath on different days. Baths were observed, timed, and scored for quality. Cultures of the peri-umbilicus and groin were obtained before and after each bath. At the end of the study, nurses were interviewed about their preferences. RESULTS: Neither total quality scores nor microbial counts differed significantly between the 2 bath types. Significantly fewer products (P < .001) and less time were used, cost was lower, and nurses' ratings were significantly better with the disposable bath. CONCLUSION: The disposable bath is a desirable form of bathing for patients who are unable to bathe themselves in critical care and long-term care settings, and it may even be preferable to the traditional basin bath.

Adult↗

Taxonomic identification of microorganisms by capture and intrinsic fluorescence detection.

Quick and accurate detection of microbial contamination is accomplished by a unique combination of leading edge technologies described in this and the accompanying article. Microbe capture chips, used with a prototype fluorescence detector, are capable of statistically sampling the environment for pathogens (including spores), identifying the specific pathogens/exotoxins, and determining cell viability where appropriate.

Adhesins, Bacterial↗

Long-term storage of small surgical instruments in autoclaved packages.

BACKGROUND: In most operating theatres, unused sterile instruments must be re-sterilized according to preset protocols. Protocols differ among institutions and are not based on strong scientific evidence. OBJECTIVE: To determine and compare the duration of sterility of small instruments packaged in double-layered linen versus plastic-paper envelopes after autoclaving. MATERIALS AND METHODS: Two groups of orthopaedic screws were simultaneously sterilized by autoclaving. In Group 1, each screw was packaged in a double-wrapped linen pack. The screws in Group 2 were individually packaged in an inner wrap of paper and an outer plastic-paper envelope that is commercially available. Unwrapped screws in Group 3 served as controls. During the first 48 weeks, five packages were randomly taken from each group, and from 48 weeks to 96 weeks, 20 packages were taken at random and sent for microbial culture. Five screws from Group 3 were also randomly picked with each sample. RESULTS: Up to 96 weeks, no organisms were cultured from any sample from Groups 1 and 2. Almost all samples from Group 3 grew several species of bacteria. CONCLUSION: For small metal instruments, autoclaved packages in double-wrapped linen or double-wrapped plastic-paper combinations can be stored safely for at least 96 weeks.

Colony Count, Microbial↗

Microbial growth in vials of Botulinum toxin following use in clinic.

PURPOSE: Botulinum toxin has various applications in ophthalmology and is used in the outpatient department, where it is often exposed to room temperatures for 3-4 h. The manufacturer's recommendations are that the reconstituted toxin be stored in a refrigerator when not in use and discarded 4 h after reconstitution. The aim of our study was to examine such used bottles of Botulinum toxin for microbial growth after 4 h at room temperature. METHODS AND RESULTS: Eleven consecutive bottles of Botulinum toxin used with aseptic precautions in the Ophthalmology outpatient clinics were exposed to room temperatures for 4 h. These were subsequently analysed for microbial growth. No growth was directly obtained from any of the Botulinum toxin bottles during our study. CONCLUSIONS: This pilot study suggests that if aseptic precautions are followed during the use of Botulinum toxin, the contents of the bottle remain sterile despite being exposed to room temperatures for up to 4 h. This has implications on the use of the reconstituted toxin after the recommended 4 h.

Asepsis↗

Reducing gaseous nitrogen loss from stored laying hen manure by the addition of carbohydrates.

Three separate experiments were conducted to determine if the addition of carbohydrate sources directly to freshly-produced laying hen manure reduced the loss of gaseous nitrogen containing compounds during 7 d of storage. The addition of sucrose (8 g/kg) to the manure resulted in a greater increase in bacterial numbers, a greater loss of carbon and a trend for a reduced loss of nitrogen. Although glucose addition to the manure increased bacterial numbers and tended to increase carbon loss, nitrogen loss increased relative to the control. Addition of straw to the manure did not affect the change in bacterial numbers or rate of nitrogen loss compared to the control treatment. Experiment 2 indicated that, when either sucrose or maltose were mixed (8 g/kg) with laying hen manure, microbial numbers were increased and gaseous nitrogen losses were reduced. A combination of starch plus alpha-amylase did not affect the characteristics of the manure. Experiment 3 showed that increasing sucrose addition gave a non-linear reduction in nitrogen loss. Minimum nitrogen loss was obtained with 35 g/kg sucrose, though the maximum increase in bacterial numbers occurred at 20 g/kg of added sucrose.

Animals↗

Microbial aerosol generation during laboratory accidents and subsequent risk assessment.

AIM: To quantify microbial aerosols generated by a series of laboratory accidents and to use these data in risk assessment. METHODS AND RESULTS: A series of laboratory accident scenarios have been devised and the microbial aerosol generated by them has been measured using a range of microbial air samplers. The accident scenarios generating the highest aerosol concentrations were, dropping a fungal plate, dropping a large bottle, centrifuge rotor leaks and a blocked syringe filter. Many of these accidents generated low particle size aerosols, which would be inhaled into the lungs of any exposed laboratory staff. Spray factors (SFs) have been calculated using the results of these experiments as an indicator of the potential for accidents to generate microbial aerosols. Model risk assessments have been described using the SF data. CONCLUSIONS: Quantitative risk assessment of laboratory accidents can provide data that can aid the design of containment laboratories and the response to laboratory accidents. SIGNIFICANCE AND IMPACT OF THE STUDY: A methodology has been described and supporting data provided to allow microbiological safety officers to carry out quantitative risk assessment of laboratory accidents.

Accidents, Occupational↗