What is an advantage of the viable plate count?
A viable cell count allows one to identify the number of actively growing/dividing cells in a sample. The plate count method or spread plate relies on bacteria growing a colony on a nutrient medium. The colony becomes visible to the naked eye and the number of colonies on a plate can be counted.
What are some advantages of direct counts over viable counts?
Advantages of Direct Microscopic Count
- Rapid, Simple and easy method requiring minimum equipment.
- Morphology of the bacteria can be observed as they counted.
- Very dense suspensions can be counted if they are diluted appropriately.
What are the disadvantages of viable plate count method?
There are several drawbacks to the viable count method. The major disadvantage is that it is selective and therefore biased. The nature of the growth conditions, including the composition and pH of the medium used as well as the conditions such as temperature, determines which bacteria in a mixed population can grow.
What is the advantage of standard plate count over an indirect method of counting bacteria?
It allows you to take the average number of colonies per plate to calculate the CFU’s it minimizes the amount of human era and results.
What are the disadvantages and advantages of viable plate count?
Despite its shortcomings, the viable plate count is a popular method for determining cell number. The technique is sensitive and has the advantage of only counting living bacteria, which is often the important issue. Any concentration of microorganism can be easily counted, if the appropriate dilution is plated.
What is the advantage of using viable count CFU ml rather than direct count cells ml?
The CFU method has two noteworthy advantages, namely the capacity for counts of any number of bacteria using dilutions, if too many, or concentrations if too few. Second, only viable bacteria are counted with this method as the CFU method excludes dead bacteria and debris.
What are the advantages of direct microscopic plate count?
Advantage of Direct Microscopic Count Rapid, Simple and easy method. Require less time to perform. A large number of samples can be screened in a given period of time. Useful in providing the estimated counts, types of bacteria and somatic cells in milk.
What is the advantage of viable cell count compared to total count?
What are the limitations of standard plate count?
Although the standard plate count provides information about the total microbial load in a food, it also has some limitations. First, the standard plate count only tells how many cells but not what kinds of cells are present. Second, only relatively rapidly growing aerobic organisms such as bacteria are enumerated.
What is meant by a viable plate count?
The viable plate count, or simply plate count, is a count of viable or live cells. It is based on the principle that viable cells replicate and give rise to visible colonies when incubated under suitable conditions for the specimen. (OpenStax CNX, 2018) A measured amount of a liquid culture is inoculated onto a plate.
What are the disadvantages of direct microscopic count?
Disadvantage of Direct Microscopic Count Small cells are not clearly visualized under the microscope. Precision is difficult to achieve. Required a phase-contrast microscope, when the sample is not stained. cell suspensions of Low-density can not be observed by using this method.
What is a viable plate count?
Despite its shortcomings, the viable plate count is a popular method for determining cell number. The technique is sensitive and has the advantage of only counting living bacteria, which is often the important issue. Any concentration of microorganism can be easily counted, if the appropriate dilution is plated.
Why does plate count underestimate the number of viable cells?
Moreover, plate count may underestimate the number of viable cells due to the viable but nonculturable state of bacteria, which is caused by cell stress or injury ( Camper and McFeters, 1979 ).
What are the limitations of the standard plate count?
Although the standard plate count provides information about the total microbial load in a food, it also has some limitations. First, the standard plate count only tells how many cells but not what kinds of cells are present. Second, only relatively rapidly growing aerobic organisms such as bacteria are enumerated.
What is the purpose of the plate count?
The purpose, as its name implies, is to estimate the number of viable microorganism cells in a given sample of food. Although the standard plate count provides information about the total microbial load in a food, it also has some limitations.