Development of Manufacturable Solutions for the Direct Plating of Copper on Robust ALD-Grown Barriers

2019 ◽  
Vol 6 (8) ◽  
pp. 77-88 ◽  
Author(s):  
Sumit Kumar ◽  
Daniel Greenslit ◽  
Eric Eisenbraun
Keyword(s):  
Direct Plating

scholarly journals Comparison of Fecal Coliform Agar and Violet Red Bile Lactose Agar for Fecal Coliform Enumeration in Foods

2002 ◽  
Vol 68 (4) ◽  
pp. 1631-1638 ◽  
Author(s):  
A. Leclercq ◽  
C. Wanegue ◽  
P. Baylac
Keyword(s):  
Escherichia Coli ◽  
Fecal Coliform ◽  
Food Samples ◽  
Fecal Coliforms ◽  
Predictive Values ◽  
Direct Plating ◽  
Hafnia Alvei ◽  
E Coli ◽  
Plating Method ◽  
Mashed Potatoes

ABSTRACT A 24-h direct plating method for fecal coliform enumeration with a resuscitation step (preincubation for 2 h at 37 ± 1°C and transfer to 44 ± 1°C for 22 h) using fecal coliform agar (FCA) was compared with the 24-h standardized violet red bile lactose agar (VRBL) method. FCA and VRBL have equivalent specificities and sensitivities, except for lactose-positive non-fecal coliforms such as Hafnia alvei, which could form typical colonies on FCA and VRBL. Recovery of cold-stressed Escherichia coli in mashed potatoes on FCA was about 1 log unit lower than that with VRBL. When the FCA method was compared with standard VRBL for enumeration of fecal coliforms, based on counting carried out on 170 different food samples, results were not significantly different (P > 0.05). Based on 203 typical identified colonies selected as found on VRBL and FCA, the latter medium appears to allow the enumeration of more true fecal coliforms and has higher performance in certain ways (specificity, sensitivity, and negative and positive predictive values) than VRBL. Most colonies clearly identified on both media were E. coli and H. alvei, a non-fecal coliform. Therefore, the replacement of fecal coliform enumeration by E. coli enumeration to estimate food sanitary quality should be recommended.

Assessment of different selective agar media for enumeration and isolation ofListeriafrom dairy products

1988 ◽  
Vol 55 (4) ◽  
pp. 579-583 ◽  
Author(s):  
Lucas Dominguez ◽  
José Francisco Fernández ◽  
Victor Briones ◽  
José Luis Blanco ◽  
Guillermo Suárez
Keyword(s):  
Dairy Products ◽  
Agar Medium ◽  
Raw Milk ◽  
Superior Performance ◽  
Direct Plating ◽  
Selective Agar ◽  
Natural Microflora ◽  
Agar Media ◽  
The Difference ◽  
Better Than

SummaryDifferent selective agar media were compared for the recovery and isolation of five species ofListeriafrom raw milk and cheese. The selective media examined were Beerens medium, MacBride medium and that described by Dominguezet al.(1984) with 6 mg/1 acriflavine, listeria selective agar medium (LSAM), and LSAM with 12 mg/1 acriflavine (LSAM × 2A); a non-selective yeast glucose Lemco agar was included for comparison. When the difference between listeria and the natural microflora of raw milk and cheese was 102cfu/ml, listeria could be isolated by direct plating on all media tested. When it was lower than 103–104cfu/ml, listeria were isolated by direct plating only on LSAM and LSAM × 2A. When the difference was greater than 104cfu/ml, a previous enrichment was necessary to isolate them. LSAM and LSAM × 2A media performed better than the other media tested for isolating listeria by direct plating and improved their isolation from dairy products. This superior performance was evaluated by the ability of these media to support colony formation of different species ofListeriatested, the easy recognition of these colonies from those formed by other microorganisms and by their capacity to inhibit the natural microflora of these foods.

scholarly journals PseudomonasDiversity in Crude-Oil-Contaminated Intertidal Sand Samples Obtained after thePrestigeOil Spill

2010 ◽  
Vol 77 (3) ◽  
pp. 1076-1085 ◽  
Author(s):  
Magdalena Mulet ◽  
Zoyla David ◽  
Balbina Nogales ◽  
Rafael Bosch ◽  
Jorge Lalucat ◽  
...  
Keyword(s):  
Carbon Sources ◽  
Species Level ◽  
Gene Library ◽  
Direct Plating ◽  
Selective Media ◽  
Dna Library ◽  
Culture Independent ◽  
Northwestern Spain ◽  
Pcr Method ◽  
Culture Dependent

ABSTRACTThe Galicia seashore, in northwestern Spain, was one of the shorelines affected by thePrestigeoil spill in November 2002. The diversity of autochthonousPseudomonaspopulations present at two beaches (Carnota municipality) was analyzed using culture-independent and culture-dependent methods. The first analysis involved the screening of anrpoDgene library. The second involved the isolation of 94Pseudomonasstrains that were able to grow on selective media by direct plating or after serial enrichments on several carbon sources: biphenyl, gentisate, hexadecane, methylnaphthalene, naphthalene, phenanthrene, salicylate, xylene, and succinate. Eight denitrifyingPseudomonasstrains were also isolated by their ability to grow anaerobically with nitrate. The calculated coverage index forPseudomonasspecies was 89% when clones and isolates were considered together, and there were 29 phylospecies detected. The most abundant were members of the speciesP. stutzeri,P.putida,P. anguilliseptica, andP. oleovorans. Thirty-one isolates could not be identified at the species level and were considered representatives of 16 putative novelPseudomonasspecies. One isolate was considered representative of a novelP. stutzerigenomovar. Concordant results were obtained when the diversities of the cloned DNA library and the cultured strains were compared. The clone library obtained by therpoDPCR method was a useful tool for evaluatingPseudomonascommunities and also for microdiversity studies ofPseudomonaspopulations.

Bacteriophage Conjugates: The Effect of Coupling Reaction and Specific Antibodies on the Kinetics of Inactivation and Reactivation

1973 ◽  
Vol 28 (1-2) ◽  
pp. 83-90
Author(s):  
Horst Mossmann ◽  
Dietrich K. Hammer
Keyword(s):  
Bacteriophage T4 ◽  
Covalent Binding ◽  
Coupling Reaction ◽  
Order Reaction ◽  
Direct Plating ◽  
Specific Antibodies ◽  
Coupling Process ◽  
First Order ◽  
Kinetics Of ◽  
Critical Site

The reaction of bacteriophage T4 with 1-fluoro-2,4-dinitrobenzene resulted in a covalent binding of 2,4-dinitrophenyl (DNP) determinants to the phage. From the kinetics of inactivation reflecting the coupling process it is concluded that attachment of more than one DNP group to the critical site(s) of the phage is required for inactivation (multi-hit reaction). Contrary to this the neutralization of DNP-T4 by anti-DNP antibody turned out to be a first order reaction, until 80 %> neutralization fitting one-hit kinetics. If compared with native T4, the susceptibility of DNP-T4 to neutralization by anti-T4 antibody is considerably higher, indicating that attachment of DNP groups to T4 amplifies the sensitivity to neutralization by anti-T4. Comparing neutralization kinetics of DNP-T4 and native T4 by anti-DNP-T4 antibody it is suggested that native determinants and DNP groups, as well as determinants resulting from alteration due to the coupling process, all together may contribute as targets for neutralization. Three characteristics strengthen the view that the velocity of T4 conjugates in infecting the host strain is markedly decreased if compared with that of native T4: (a) considerable discrepancy between direct plating and decision technique (b) increasing variety of plaque size and (c) decreased velocity of the first step of reproduction. The kinetics of neutralization observed can be reconciled with a model proposed by Krummel and Uhr. The kinetics of reactivation of neutralized DNP-T4 by the presence cf DNP-BSA has been investigated and the problems involved in the reaction are discussed.

scholarly journals Comparing the Yield of Staphylococcus aureus Recovery with Static versus Agitated Broth Incubation

2018 ◽  
Vol 2018 ◽  
pp. 1-3
Author(s):  
Carol E. Muenks ◽  
Patrick G. Hogan ◽  
Carey-Ann D. Burnham ◽  
Stephanie A. Fritz
Keyword(s):  
Staphylococcus Aureus ◽  
Enrichment Culture ◽  
Culture Method ◽  
Ambient Air ◽  
Built Environments ◽  
Culture Methods ◽  
Semiquantitative Assessment ◽  
Direct Plating ◽  
Static Conditions ◽  
Broth Enrichment

Given the lack of standardization of methodologies for microbial recovery from built environments, we sought to compare the yield of Staphylococcus aureus with a broth enrichment method when incubated in agitated versus static conditions. Five unique strains of S. aureus at five different concentrations were cultured to compare direct plating, agitated broth enrichment, and static broth enrichment culture methods. All samples were incubated at 35° in ambient air. The lowest concentration recovered across three replicates and five strains did not differ between culture methods (Fisher’s exact test, p=0.50); notably, recovery of S. aureus was equivalent between static and agitated broth incubation. When broth enrichment was used (both static and agitated), the burden of S. aureus growth was higher (by semiquantitative assessment of 4-quadrant streaking) compared to the direct plating culture method. Optimizing strategies for microbial recovery is essential, particularly in areas of lower biomass, given the paucity of research concerning microbial communities of built environments. The results of this study, in conjunction with other experiments investigating microbiomes of built environments, can help inform protocols for standardizing culturing methods within built environments.

scholarly journals A Clean-In-Place Type Sanitation Method Validation for a Benchtop Meat Grinder

2019 ◽  
Vol 3 (2) ◽  
Author(s):  
C. E. Rayfield ◽  
R. Jadeja ◽  
S. Billups
Keyword(s):  
Lactic Acid ◽  
Foodborne Pathogens ◽  
Peracetic Acid ◽  
Deionized Water ◽  
Cross Contamination ◽  
Direct Plating ◽  
Water Ice ◽  
E Coli ◽  
Different Types ◽  
Low Levels

ObjectivesThis research is designed to validate a novel clean-in-place type antimicrobial ice-based meat grinder sanitation method.Materials and MethodsFour different types of antimicrobial ice were prepared from peracetic acid (PAA, 350 mg/L) and combination PAA with 2% FreshFX® (PAAF), 2% Paradigm® (PAAP) and 2% lactic acid (PAAL). The grinders were inoculated by processing 400 g beef trim containing 400 μL of E. coli O157:H7 or S. Typhimurium DT 104 suspensions at 8.4 to 8.7 (high inoculation) and 5.3 to 5.5 (low inoculation) log CFU/mL. Each meat grinder was then treated by processing 1000 g of antimicrobial ice and 500 mL of corresponding antimicrobial solution. At the end of each treatment, 400 g un-inoculated beef was processed through the meat grinder, and the resulting ground beef was then analyzed for the presence of target pathogens by direct plating and after enrichment. Efficacies of antimicrobial ice-based treatments were compared with 1000 g deionized water ice + 500 mL deionized water (DI), and no treatment (NT) controls.ResultsAll antimicrobial ice treatments were able to reduce cross-contamination to non-detectable levels from the meat grinders inoculated at the low levels of pathogens, but after enrichment, target pathogens were detected in all the samples. Recoveries from the meat grinder inoculated with high levels of pathogens ranged from 5.95 to 3.50 log CFU/g and 5.86 to 3.46 log CFU/g for E. coli O157:H7 and S. Typhimurium DT 104, respectively. All antimicrobial ice treatments were significantly (p ≤ 0.05) more effective in reducing cross-contamination in comparison of NT and DI controls. The microbial reductions achieved by different antimicrobial ice treatments were not significantly (p ≤ 0.05) different from each other.ConclusionThe antimicrobial ice-based meat grinder sanitation technique could effectively reduce foodborne pathogens from meat grinders without needing meat grinder disassembly.

Isolation Method (Direct Plating or Enrichment) does Not Affect Antimicrobial Susceptibility ofCampylobacterfrom Chicken Carcasses

2016 ◽  
Vol 37 (1) ◽  
pp. e12279 ◽  
Author(s):  
Scott R. Ladely ◽  
Richard J. Meinersmann ◽  
Jodie R. Plumblee ◽  
Paula J. Fedorka-Cray
Keyword(s):  
Antimicrobial Susceptibility ◽  
Isolation Method ◽  
Direct Plating

Postchill Campylobacter Prevalence on Broiler Carcasses in Relation to Slaughter Group Colonization Level and Chilling System

2006 ◽  
Vol 69 (3) ◽  
pp. 495-499 ◽  
Author(s):  
M. LINDBLAD ◽  
I. HANSSON ◽  
I. VÅGSHOLM ◽  
R. LINDQVIST
Keyword(s):  
Campylobacter Jejuni ◽  
Surveillance Program ◽  
Intestinal Colonization ◽  
Direct Plating ◽  
Baseline Study ◽  
Group Data ◽  
Low Degree ◽  
High Degree ◽  
Campylobacter Spp ◽  
Skin Samples

Data from an ongoing national surveillance program of Campylobacter prevalence in broiler slaughter groups were related to results from a 1-year baseline study of broiler carcasses postchill. The goals were to establish the relation between Campylobacter prevalence in slaughter groups and on carcasses and to determine the effect of various chilling systems on Campylobacter prevalence. Pooled cloacal and neck skin samples from the surveillance program were analyzed after enrichment. Carcass rinse samples from the baseline study were analyzed after enrichment and by direct plating. Data from both studies were available for 614 carcasses. Direct-plating analyses indicated that the percentages of carcasses positive for Campylobacter jejuni and other Campylobacter spp. in slaughter groups with negative cloacal samples were 2 and 10%, respectively, whereas enrichment analyses indicated prevalences of 2% in both cases. Campylobacter prevalence in slaughter groups with a high degree of intestinal colonization (more than half of the pooled cloacal samples positive) was significantly higher than in slaughter groups with a low degree of colonization (76 to 85% and 30 to 50%, respectively, depending on Campylobacter spp. and analytical method). The prevalence of Campylobacter-positive carcasses postchill was at the same level as the prevalence of carcasses that originated from slaughter groups with positive neck skin samples at four of the six slaughterhouses. Only at one slaughterhouse, with an air-chilling system, was the postchill prevalence (13%) lower than that expected from slaughter group data (23%). The postchill prevalence (43%) was higher than that expected from slaughter group data (33%) at one slaughterhouse with immersion chilling.

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