Microbiology of food and animal feeding stuffs - Horizontal method for the enumeration of presumptive Bacillus cereus - Colony-count technique at 30 degrees C

Abstract Bacterial contamination of blood and blood components is a major safety concern in transfusion medicine. In order to facilitate safer transfusion products to the end users, there is a critical need for novel proof-of-concept ideas for pathogen reduction, which are different from the current ones that outweigh the associated toxicity and/or contamination risk. Present study involves use of nine novel synthetic antimicrobial peptides (four originated from thrombin-induced human platelet derived antimicrobial proteins named PP1-PP4 and five having 1–5 repeats of arginine and tryptophan residues, named DP1-DP5. These peptides were tested on plasma samples spiked with 10-fold dilutions of 5 different bacteria (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Bacillus cereus) that are important to the field of transfusion medicine and analyzed whether these spiked plasma samples could be cured of the pathogens. Each spiked sample was incubated with a peptide (PP1-PP4 and DP1-DP5) for 2 hours at 37°C. Following incubation, a fixed volume of the inoculum was plated on nutrient agar plates and incubated overnight at 37°C for colony count. Spiked sample without any peptide was included as control. Results revealed that out of nine peptides tested, while DP3 and DP4 were active against all 5 organisms tested resulting in 50–100 % of inhibition of specific organisms, peptide PP4 was only active against E. coli, P. aeruginosa and Bacillus cereus resulting in a 30–100% reduction in the CFU/ml compared to the controls. Table 1 Organism Colony count expressed in % Control PP1 PP2 PP3 PP4 DP1 DP2 DP3 DP4 DP5 S. aureus 100 90 100 26 100 100 20 10 56 100 E. coli 100 95 100 100 71 100 93 4 18 85 P. aeruginosa 100 100 100 100 0 100 0 0 13 100 K. pneumoniae 100 100 100 100 100 74 3 0 0 25 B. cereus 100 100 100 100 50 100 100 25 77 100 Based on these results, it appears that peptides used in this study provide a new antibacterial strategy against a range of bacteria and with further studies and refinement, these peptides could prove useful towards bacterial reduction in blood and blood products. The findings and conclusions in this abstract have not been formally disseminated by the Food and Drug Administration and should not be construed to represent any Agency determination or policy.

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Investigations of influence of disinfection procedures on hygiene in private slaughterhouse

Veterinarski glasnik ◽

10.2298/vetgl1204219j ◽

2012 ◽

Vol 66 (3-4) ◽

pp. 219-231

Author(s):

Ljiljana Jankovic ◽

Brana Radenkovic-Damnjanovic ◽

Nedjeljko Karabasil ◽

Milorad Mirilovic ◽

Slobodan Maric

Keyword(s):

Standard Method ◽

Exposure Period ◽

Colony Count ◽

Sampling Techniques ◽

Commission Decision ◽

Skilled Professional ◽

Before And After ◽

Sodium Dichloroisocyanurate ◽

Animal Feeding ◽

Number Of Bacteria

The objective of this work was to establish, on the grounds of obtained results for the total number of bacteria before and after completed disinfection, whether there are differences in the efficiency of disinfection performed by a professional and disinfection carried out by an unqualified employee in a private slaughterhouse. The material used in these investigations were samples of wet-dry swabs taken over a course of five weeks, before and after disinfection carried out by an unqualified employee and the skilled professional, from the following: the knife used for evisceration, the floor in the evisceration area, from the table serving for bristle removal, and from the floor underneath the bristle removal surface. The wet-dry swabs were taken according to the procedure described in the standard method ISO 18593 (Microbiology of food and animal feeding stuffs - Horizontal methods for sampling techniques from surfaces using contact plates and swabs). Analyzing the taken samples, the total number of bacteria was determined using the standard method ISO 4833 (Microbiology of food and animal feeding stuffs - Horizontal method for the enumeration of microorganisms - Colony-count technique at 30?C). Disinfection was carried out using a chlorine preparation (sodium dichloroisocyanurate dihydrate) in a concentration of 0.02% and for an exposure period of 30 min. The results were interpreted on the grounds of the border values in evaluating the hygiene of the equipment, tools, and work surfaces, presented in Commission Decision 471/2001/ EC. The results of the investogations have shown that the disinfection performed by the skilled professional was more efficient than the disinfection performed by the unqualified person, as the total number of bacteria was significantly smaller (p<0.01) in the course of all 5 experimental weeks on the evisceration knife, the floor under the bristle removal surface, during weeks 1, 2 and 5, and on the floor in the evisceration area in weeks 1 and 5.

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Microbiology of food and animal feeding stuffs. Horizontal method for the enumeration of coliforms. Colony-count technique

10.3403/30113863u ◽

2015 ◽

Cited By ~ 1

Keyword(s):

Colony Count ◽

Animal Feeding

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Microbiological Quality of Dry Dessert Mixes Sold in Canada

Journal of Food Protection ◽

10.4315/0362-028x-50.2.136 ◽

1987 ◽

Vol 50 (2) ◽

pp. 136-140 ◽

Cited By ~ 4

Author(s):

D.W. WARBLTRTON ◽

P.I. PETERKIN ◽

G.A. JARVIS ◽

K.F. WEISS ◽

G. RIEDEL

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Bacillus Cereus ◽

Microbiological Quality ◽

Colony Count ◽

Practical Consideration ◽

Bacteriological Quality

A study done in 1977–1978, assessed the bacteriological quality of five types of dry desserts including starch-, gelatin- and rennet- based products. One hundred and ninety-seven lots were randomly selected across Canada and analyzed for aerobic colony count, aerobic sporeformers, Bacillus cereus, coliforms, Escherichia coli, Staphylococcus aureus and Salmonella. Micro-biological and practical consideration do not warrant the establishment of standards or guidelines for such products at this time.

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