• 6. What Are Some Advantages And Disadvantages Of The Serial Dilution Agar Plate Technique

As a result, if you only see one type of microorganism growing in the culture, then you know that you have used the aseptic technique correctly and have achieves a pure culture. However, if you see one or more microorganisms growing in the culture, then you have created a mixed culture, and somewhere along the way the aseptic technique was likely not performed correctly, allowing for some type of contamination of another microorganism. If this happens, you should perform the process over again using the aseptic technique until your results yield a pure culture.

Continue making plates in this fashion from each of the dilution tubes until you have created four plates: 1:20, 1:200, 1:2000, 1:20000. Place the plates to be incubated.

Discrete colonies can appear from a mixed culture using the streak-plate method. The streak plate method involves picking up cells from a selected colony on the end of a sterile loop and transferring them to a part of the agar by 'streaking' the loop across the surface of the agar. Using proper aseptic technique and streaking the first area, the loop is re-sterilized by passing it through the Bunsen Burner and then streaked across the edge of the first area in order to make a new area of deposited cells. This process is then repeated for a third and fourth area, so that the original cells in area one are now spread out and can develop into isolated colonies. The lid of the petri dish is also carefully removed and only taken off when streaking the plate in order to avoid any air contamination from getting onto the area.

Find outboard engine specs, special financing, accessories. • what are the advantages of the serial dilution agar plate procedure. Advantage: the cell count represents viable cells. Disadvantage: the method requires an.

According to the online Lab, agar plates are sterile petri plates filled with a solidified sterile agar and are used primarily for the purpose of culturing, separating, and the counting of microorganisms. This type of medium is best used for displaying well-isolated colonies that can be evaluated for their size, pigmentation, form, margin, and elevation. The size of the colonies incubated on the agar plates can range from very small to large. The shape (form) can appear as circular, irregular, or rhizoid. The margin (which is what the outside edge of the colony looks like) can range in appearance in ways known as entire, lobate, undulate, serrate, or filamentous, all of which have different patterns of growth associated with this outside edge. The elevation (degree at which colony is raised on agar surface) is another cultural characteristic of the agar plate, which can be flat, raised, convex, or umbondate.

For example, if A 280 says you have 7.0 mg total protein/ml, and you think the protein could be anywhere between 10% and 100% pure, then your assay needs to be able to see anything between 0.7 and 7 mg/ml. That means you need to cover a ten-fold range of dilutions, or maybe a bit more to be sure. If the half-max of your assay occurs at about 0.5 mg/ml, then your minimum dilution fold is (700 mg/ml)/(0.5 mg/ml) = 1,400. Your maximum is (7000 mg/ml)/(0.5 mg/ml) = 14,000. So to be safe, you might want to cover 1,000 through 20,000. In general, before designing a dilution series, you need to decide: • What are the lowest and highest concentrations (or dilutions) you need to test in order to be certain of finding the half-max?

For example: 1/3, 1/9, 1/27, 1/81 Notice that each dilution is three-fold relative to the previous one. In four dilutions, we have covered a range of 181/3 = 60-fold.

I completed bsc microbiology,DMLT and i finished ILETS exam and got overall 5.5 score,is it possible to get job in melbourne hospital,wat i hav to do What is the trouble in growing streptococcus species? How to prepare and store agar? Why is partial purification of enzyme done in some cases not complete purification? What are the problems of Frozen transformed bacterial cells? ::,,,,,,,.:: Banking Finance, Business Administration, Funding, Hotel Management, Human Resources, IT Management, Industrial Management, Infrastructure Management, Marketing Sales, Operations Management, Personnel Management, Supply Chain Management.:: Aeronautical, Automobile, Bio, Chemical, Civil, Electrical, Electronics Communications, Industrial, Instrumentation, Marine, Mechanical, Mechatronics, Metallurgy, Power Plant.:: USA Visa, UK Visa, Australia Visa, Canada Visa, Germany Visa, New Zealand Visa. . Copyright © 2018 ALLInterview.com.

According to the video on the proper aseptic techniques for use in a laboratory, one reason that aseptic technique is necessary is to protect oneself from contact with biohazards that exist within a lab setting. Additionally, it serves the purpose to protect samples from being contaminated. Aseptic technique is also extremely important for safeguarding others in the lab. Since bacteria are everywhere, including on all of the lab equipment, aseptic techniques allow us to avoid the spread of infection in the above ways.

• Lift the lid of the Petri dish slightly with the left hand and pour the sterile molten agar into the Petri dish and replace the the lid. • Flame the neck of the bottle and replace the cap. • Gently rotate the dish to mix the culture and the medium thoroughly and to ensure that the medium covers the plate evenly.

When you need to cover several factors of ten (several 'orders of magnitude') with a series of dilutions, it usually makes the most sense to plot the dilutions (relative concentrations) on a logarithmic scale. This avoids bunching most of the points up at one end and having just the last point way far down the scale.

If this happens, you should perform the process over again using the aseptic technique until your results yield a pure culture. The serial dilution agar plate technique is when you dilute a sample several times to achieve several different dilutions. For example, if you are working with a urine sample that you need to test for the presence of microorganisms. This technique can have both some advantages and disadvantages. Using the same example, since you don't know the concentration of the microorganisms in the urine, then you don't know which dilution you need to make in order to make a countable solution. If you perform a 10% dilution, for example, then it might end up being too concentrated (and you will have too many microorganisms to count).

6. What Are Some Advantages And Disadvantages Of The Serial Dilution Agar Plate Technique

This is in order to keep the tube free of contamination. The increased temperature at the mouth of the tube works to create a confection-oven-like current, which pushes the air out of the tube and eliminates the potential for airborne contaminants to get into the mouth of the tube. The presence of the Bunsen Burner in the lab area also serves to decrease the amount of airborne contamination, but this process ensures that anything that may still be present in the air does not enter the tube. The correct way to successfully perform this procedure is to pass the tube over the flame at a 45-degree angle. A pure culture is a culture that only has one type of microorganism growing in it. As a result, if you only see one type of microorganism growing in the culture, then you know that you have used the aseptic technique correctly and have achieves a pure culture. However, if you see one or more microorganisms growing in the culture, then you have created a mixed culture, and somewhere along the way the aseptic technique was likely not performed correctly, allowing for some type of contamination of another microorganism.

This is in order to keep the tube free of contamination. The increased temperature at the mouth of the tube works to create a confection-oven-like current, which pushes the air out of the tube and eliminates the potential for airborne contaminants to get into the mouth of the tube. The presence of the Bunsen Burner in the lab area also serves to decrease the amount of airborne contamination, but this process ensures that anything that may still be present in the air does not enter the tube. The correct way to successfully perform this procedure is to pass the tube over the flame at a 45-degree angle.

You might think it would be good to dilute 1/2, 1/3, 1/10, 1/100. These seem like nice numbers.

• Oct 19, 2011. There are several benefits of performing serial dilution. Serial dilution comes in handy when the solution is too concentrated to be used in. • To perform a serial dilution, a small amount of a well-mixed solution is transferred into a new container and additional water or other solvent * is added to dilute.

The correct way to successfully perform this procedure is to pass the tube over the flame at a 45-degree angle. A pure culture is a culture that only has one type of microorganism growing in it. As a result, if you only see one type of microorganism growing in the culture, then you know that you have used the aseptic technique correctly and have achieves a pure culture. However, if you see one or more microorganisms growing in the culture, then you have created a mixed culture, and somewhere along the way the aseptic technique was likely not performed correctly, allowing for some type of contamination of another microorganism.

It may be observed as appearing as finely dispersed and cloudy. This is known as uniform turbidity. The culture can also be classified as flocculent, which appears flaky with aggregates distributed throughout the area. If it shows up as a thick, pad-like growth then it's known as pellicle. If a concentrated growth at the bottom of the culture medium grows in a granular, flaky, or flocculent means, then this is known as sediment. Perhaps one of the major advantages to using an agar plate over a slant tube is that the agar plates are much less confining, and allow for a much larger surface area for growth and streaking. This greater surface area also allows for showing areas of well-isolated colonies better.

You end up with 1.0 ml of each dilution. If that is enough to perform all of your tests, this dilution plan will work. If you need larger volumes, increase the volumes you use to make your dilutions (e.g. 2.0 ml + 2.0 ml in each step).

Pouring the molten agar and incubation • Collect one bottle of sterile molten agar (containing 15 mL of melted Plate Count Agar or any other standard culture media) from the water bath (45°C). Pouring the molten agar medium • Hold the bottle in the right hand; remove the cap with the little finger of the left hand. • Flame the neck of the bottle. • Lift the lid of the Petri dish slightly with the left hand and pour the sterile molten agar into the Petri dish and replace the the lid. • Flame the neck of the bottle and replace the cap.

• What Are The Advantages And Disadvantages Of The Serial Dilution? - Crowdsourced Questions & Answers at Okela • Answer to What are the advantages and disadvantages of the serial dilution-agar plate procedure? • Lab Skills: Dilution Arithmetic - Advanced. The purpose of dilution is to decrease the concentration of cells (or other substance of interest) in a sample to a useful. • Advantages And Disadvantages Of Serial Dilution Honda Marine - 4-stroke outboard motors from 2 to 250 hp.

A technique known as serial dilution has been. What are the main advantages of the membrane filter technique for fecal coliform. This procedure is used to identify the number of viable micro-organisms in a fixed amount of a liquid. It can also be fairly easily modified to give results.

How to isolate the bacterial spores? What are nk cells or natural killer cells? Explain about genomic DNA extraction for PCR? Explain the Quantitative PCR for Intestinal Samples? How to isolate the microorganismes from soils? What is Cell Bank Purity? How will you convert a 6 Normal solution to 8 N soloution?

'Agar and broth dilution methods to determine the minimal inhibitory concentration (MIC) of antimicrobial substances'. Nature Protocols. • European Committee for Antimicrobial Susceptibility Testing of the European Society of Clinical Microbiology and Infectious Disease (September 2000). 'Determination of minimum inhibitory concentrations (MICs) of antibacterial agents by agar dilution'. Clinical Microbiology and Infection. 6 (9): 509–515.

The nutrient medium is solidified at an angle in order to create a flat surface for inoculation. At their surface, the agar slants have one straight line of inoculation. The cultural characteristics shown include an abundance of growth that measures as none, slight, moderate, or large. Pigmentation is another way of identification of this particular culture medium. According to the online lab, chromogenic microorganisms can produce intracellular pigments (and this is what are responsible for the coloring of the organisms in surface colonies).

The loop is flamed to kill off any bacteria still on it, then a couple streaks are made out of the original. This grabs some of the bacteria from that concentrated streak and spreads them out. This is repeated once more until the final streaks are less and less concentrated bacteria. When we incubate the plate we'll find lots of growth where the original streak was and less and less as we follow the path of the 3-phases.

After the incubation period, this medium is classified based on the distribution appearance or the growth of the culture. It may be observed as appearing as finely dispersed and cloudy. This is known as uniform turbidity. The culture can also be classified as flocculent, which appears flaky with aggregates distributed throughout the area.

If a concentrated growth at the bottom of the culture medium grows in a granular, flaky, or flocculent means, then this is known as sediment. Inpage download online. Perhaps one of the major advantages to using an agar plate over a slant tube is that the agar plates are much less confining, and allow for a much larger surface area for growth and streaking. This greater surface area also allows for showing areas of well-isolated colonies better.

The dilution factor chosen for the series of calibration standards is achievable by using serial dilution. The progression of calibration standard concentration is always a geometric series. Consider the example of making the first standard at 1/3 the concentration of the known, the next calibrant would be 1/9th the concentration of the known and the following two calibrants formed are 1/27th and 1/81st. This becomes a much greater advantage when the span of the calibration standards must cover several orders of magnitude in concentration.

The number of microorganisms present in the particular test sample is determined using the formula: CFU/mL= CFU * dilution factor * 1/aliquot For accurate counts, the optimum count should be within the range of 30-300 colonies/plate. To insure a countable plate a series of dilutions should be plated.The pour plate method of counting bacteria is more precise than the, but, on the average, it will give a lower count as heat sensitive microorganisms may die when they come contact with hot, molten agar medium.

The lowest concentration of antibiotics that prevented bacterial growth is considered to be the minimum inhibitory concentration of that antibiotic against that bacterium. Advantages [ ] Agar dilution is considered to be the of susceptibility testing, or the most accurate way to measure the resistance of bacteria to antibiotics. The results of agar dilution are easily reproduced and they can be monitored at a much cheaper cost than what is required of other dilution methods. Additionally, up to thirty pathogen samples (plus two controls) can be tested at once, so agar dilution is useful for batch tests.: 149 Disadvantages [ ] Each dilution plate in agar testing has to be manually inoculated with the pathogen to be tested, so agar dilution testing is both labor-intensive and expensive.: 149 Unlike tests, agar dilution cannot be used to test more than one antibiotic at a time.

• Seal and incubate the plate in an inverted position at 37°C for 24-48 hours. Overview of Pour plate method and spread plate method Results: After 24-48 hours, count all the colonies ( again: note that the embedded colonies will be much smaller than those which happen to form on the surface). A magnifying colony counter can aid in counting small embedded colonies. Calculate CFU/mL using the formula: CFU/mL= CFU * dilution factor * 1/aliquot (the volume of diluted specimen (aliquot) is either 0.1 or 1.0 mL) Disadvantages of Pour plate method • Preparation for pour plate method is time consuming compared with streak plate/and or spread plate technique.

• Embedded colonies are much smaller than those which happen to be on the surface. Thus, one must be careful to score these so that none are overlooked. • Reduced growth rate of obligate aerobes in the depth of the agar. References and further readings • Basic Practical Microbiology A Manual by Society for General Microbiology (SGM).

The video demonstrates the need for the step of passing the mouth of the tube through the flame. This is in order to keep the tube free of contamination. The increased temperature at the mouth of the tube works to create a confection-oven-like current, which pushes the air out of the tube and eliminates the potential for airborne contaminants to get into the mouth of the tube. The presence of the Bunsen Burner in the lab area also serves to decrease the amount of airborne contamination, but this process ensures that anything that may still be present in the air does not enter the tube.

• 4-2-2009 What are the advantages and disadvantages of the serial dilution - agar plate procedure? • Although not a serial dilution, the below is an example of a two-fold dilution. Problem #4: To make a two-fold dilution of 10 mL of solution, what amount of solvent. • Advantage And Disadvantage Of The Serial Dilution Agar Plate Procedure?

However, it can be a really helpful as it allows you to take a heavily concentrated solution and put it into a manageable sample which allows you to count and work with it. It can also be advantageous in that only viable cells can be counted and the technique allows for the isolation of specific colonies that can then be subcultured into pure cultures.

• Advantages of 'Serial Dilutions'. This section is not a recipe for your experiment. It explains some principles for designing dilutions that give optimal results. • Study online flashcards and notes for Serial Dilution method including Advantages of serial dilution-agar plate: 1. Only viable cells counted 2.

However, the disadvantage behind conducting a serial.

They are also evaluated based on the amount of light that is transmitted through the culture, which can range from levels of opaque, translucent, or transparent. The culture's form can also be evaluated based on the single streak that appears at the surface of the agar. This is classified as filiform, echinulate, beaded, effuse, absorbent, or rhizoid depending on the form it takes on. Nutrient broth tubes contain a liquid medium.

• The technique used to make a single dilution is repeated sequentially using more and more dilute solutions as the 'stock' solution. At each step, 1ml of the previous. • The first step in making a serial dilution is to take a known volume (usually 1ml) of stock and place it into a known volume of distilled water (usually 9ml). • To perform a serial dilution, a small amount of a well-mixed solution is transferred into a new container and additional water or other solvent * is added to dilute. • Although not a serial dilution, the below is an example of a two-fold dilution.