Interpretation Guide Petrifilm™
精神压力大怎么办
Environmental Listeria Plate
This guide familiarizes you with results on 3M™Petrifilm™Environmental Listeria Plates. For more information, contact the official 3M Microbiology reprentative nearest you.
The 3M™Petrifilm™Environmental Listeria (EL) Plate is a sample-ready culture medium containing lective agents, nutrients, a cold-water-soluble gelling agent, and a chromogenic indicator that facilitates Listeria colony detection. 3M Petrifilm EL plates were designed to analyze environmental samples and to help increa the
efficiency of monitoring plant sanitation. The prence of indicator Listeria such as Listeria innocua provides evidence that environmental conditions are suitable for the occurrence of Listeria monocytogenes. The 3M
Petrifilm EL plate detects the majority of environmental Listeria, consisting of Listeria monocytogenes, Listeria innocua, and Listeria welshimeri.*
Many organisms in the environment can be stresd by environmental conditions or sanitizers. Buffere
d peptone water (BPW) is ud as a repair broth in conjunction with the 3M Petrifilm EL plate to resuscitate stresd Listeria without increasing their numbers. Repair in BPW is not an enrichment step.
1
2
* For further information on the prevalence of Listeria species, plea contact the of
L. ivanovii, L. grayi/murrayi and L. eligeri grow but do not form typical colonies.
凉拌莲藕沸腾的反义词3M ™
Petrifilm
护肝食物有哪些
™
Environmental Listeria Plate
失败3a. Prior to the full 30 hour incubation, if any colonies are prent but are not inten red-violet (for e
xample, grey or light pink, as shown in 3a), then continue incubating up to 30 hours. At the maximum incubation time of 30hours, colonies that do not turn inten red-violet (colonies remain grey or light pink, as shown in 3a),should not be interpreted as Listeria .Quantitative Interpretation :Listeria colonies on this plate: <1. Plea refer to the “Quantitative Sampling” ction of this guide for calculating the quantity of Listeria per environmental sample.
Semi-Quantitative Interpretation:Listeria level should be recorded as categories that are meaningful to your sampling location and your individual plant standards (e.g., low, medium, high, or acceptable and unacceptable).Qualitative Interpretation:Listeria not detected
Quantitative Interpretation :Listeria colonies on this plate: 3. Plea refer to the “Quantitative Sampling” ction of this guide for calculating the quantity of Listeria per environmental sample.
Semi-Quantitative Interpretation:Listeria level should be recorded as categories that are meaningful to your sampling location and your individual plant standards (e.g., low, medium, high, or acceptable and unacceptable).Qualitative Interpretation:Listeria detected
Note: Do not consider or count colonies on the foam dam
since they are removed from the lective influence of the medium.
3b. At the maximum incubation time of 30 hours, colonies that were grey or light pink and changed to inten red-violet during incubation (as shown in 3b) should be interpreted as Listeria .3a.
3b.
Several factors influence the rate at which the chromogenic indicator changes to inten red-violet, including the strain and the nature and degree of stress to which the organism has been expod.
3M ™
Petrifilm
™
小学升初中Environmental Listeria Plate
Quantitative Interpretation :Estimated Listeria colonies on this plate: est. 600. When large numbers of Listeria are prent, estimate by determining the count per square of two or more reprentative squares. Determine the average per square and then multiply by 42. The inoculated area of the plate is approximately 42 cm 2.
Semi-Quantitative Interpretation:Listeria level should be recorded as categories that are meaningful to your sampling location and your individual plant standards (e.g., low, medium, high, or acceptable and unacceptable).Qualitative Interpretation:Listeria detected
Quantitative Interpretation:Listeria on this plate is too numerous to count (TNTC, approximately 104shown in this image).
Semi-Quantitative Interpretation :Listeria level should be recorded as categories that are meaningful to your sampling location and your individual plant standards (e.g., low, medium, high, or acceptable and unacceptable).Qualitative Interpretation:Listeria detected
5. When colonies are prent in large numbers, 3M Petrifilm EL Plates may have many small, indistinct colonies and/or a pink-brown color throughout.4
5
6.Background color may vary due to the prence of dust, soil, grit, or other diment from the environment sampled, or the type of sample collection device and/or the brand of buffered peptone water (repair broth). Interpret or count the inten red-violet colonies as Listeria . Quantitative Interpretation:Listeria colonies on this plate: 11. Plea refer to the “Quantitative Sampling”
ction of this guide for calculating the quantity of Listeria per environmental sample.
Semi-Quantitative Interpretation:Listeria level should be recorded as categories that are meaningful to your sampling location and your individual plant standards (e.g., low, medium, high, or acceptable and unacceptable).Qualitative Interpretation:Listeria detected
4. Since the 3M Petrifilm EL Plate may be interpreted in three ways, no counting range is suggested. When colonies are crowded, interpret the result (qualitative or mi-quantitative)or estimate the count (quantitative) as described below.6一加一不是二打一字谜
™™
surface. Lift top film.equivalent pipettor held perpendicular
to 3M Petrifilm EL Plate, place 3 mL of
合作的重要性sample onto the center of bottom film.
