Learn streak plate method with free interactive flashcards. Minimize the amount of agar and the length of time the agar is exposed to the environment during the streak process. A small amount of the mixed culture is transferred aseptically to the agar plate, and using a sterile loop, the organisms are spread streaked across the surface. Lab 2 isolation the streak plate method flashcards quizlet. Procedure the students at each tableside will work together as a group. A streak plate is a square of unglazed porcelain that has a rough surface you can use to help identify the gemstone. Isolation and observation of bacteria using pure culture.
Pour plate technique for bacterial enumeration david b. The dilution or isolation by streaking method was first developed by loeffler and gaffky in kochs laboratory, which. Information technology resources, news, and service information at msu. Eventually, it will wear out and you need to change it every once in a while. Lie the plate flat on a workbench, table, or desk so its stable. Sep 21, 2010 the most common method of separating bacteria cell on agar surface to obtain isolated colonies is the streak method to inoculate petri dish. This is too many for us to count so we dilute the sample. Sterilize the loop again in the flame and cool it at the edge of the agar away from the bacteria in the plate that you just streaked. Procedures for the recovery of legionella from the environment manual.
Answer enrichment culturing the streak plate technique. The quadrant streak method see the article on quadrant streaking is good for obtaining wellisolated. Turn the plate 90, overlap the previous area 12 times, and streak into the next quadrant as in step 4. Prepare serial dilutions of the broth culture as shown in the figure from a previous lab exercise isolation of pure cultures. A new tab or window will open, taking you to a form in our it. One very common way to isolate bacterial and other microbes is by employing the streak plate technique. The spread plate seems to be your method of choice when compared with the mpn for any application with the following exceptions. The streak plate method of isolation means to spread the microbes on plated agar media so that the individual cells or colony forming units cfus can become isolated and grow into individual, pure colonies. Label and date the plate on the bottom of the plate. Streak plate is a costeffective and rapidactive method for separating bacteria in mixed cultures of high density and can also be repeated for achieving the desired purity. The inoculum is streaked over the agar surface in such a way that it thins out the bacteria. A comparison of pour plate and spread plate methods. Lab 2 isolation the streak plate method flashcards.
Streak plate 11 pour plate 12 using a spreader spread plate 14 working with moulds 15 incubation 16. The initial inoculum is placed in the top half of the plate. For best results, let the gel harden for several hours before using. What advantage does the streakplate method have over the. Full text get a printable copy pdf file of the complete article 364k, or click on a page image below to browse page by page. Example of a microbiology unknown lab report by taylor autry. Full text get a printable copy pdf file of the complete article 364k, or click on a. Streak plate methods vary by the number of agar sections streaked. Again sterilize loop in flame of bunsen burner or hub of microincinerator, and allow loop to cool. Using sterile technique transfer a loop of bacterial culture or single colony onto loop 4. Incubate the spread agar plate at the appropriate temperature in an inverted. The dish is then rotated gently, or moved back and forth first ns, then. Streak the plate, following either the t method or quadrant streak shown below.
Bacteria are dragged from the top section to one of the bottom sections, then from that bottom section to the other. Click on the form you are interested in from the list below. Procedures for the recovery of legionella from the. Streak the loop containing the bacteria at the top end of the agar plate moving in a zigzag horizontal pattern until of the plate is covered. Full text get a printable copy pdf file of the complete article 209k, or click on a page image below to browse page by page. Streak plating is a method that allows microorganisms to be grown from a sample on an agar plate. This uses either the threestreak or fourstreak methods.
When you have a streak plate, your endgoal is to isolate individual colonies of your microbe. Streak plate method to purify single bacteria performing a plate streak i 1. Then, we put the tip on the agar surface of a new plate, and moved softly as. In addition cdhit outputs a cluster file, documenting the. Streak plate method, spread place method, pour plate method, point. Manage your deals, support queue and more inside gmail. Label the bottom of the plate with the above data plus initials, seat number and date. The method most often used in the clinical laboratory is the quadrant method. For the other tsa plate, using the above procedure as a guide, perform the streak plate using the fourphase method. Using a new agar plate, lift the lid just enough to insert the loop. What are the disadvantages of the streak plate method. The streak plate method will require constant use of the streaking loop. First session streaking for isolation by the quadrant method 1.
Method 1 streak plate swabbing 1 remove petri dishes from their sleeve and lay them on a level surface with the lid side up. Flame metal inoculating loop, let cool momentarily. Principle the streak plate technique is essentially a method to dilute the number of organisms, decreasing the density. Upon returning and observing the streak plate, there was an abundance of green across the plate. New or revised documents should be controlled within the laboratory in accordance.
Step 1, we touched one single colony on a cultured plate we made before with the loops tip. Samples can then be taken from the resulting colonies and a microbiological culture can be grown on a new plate so that the organism can be identified, studied, or tested. The pour plate method of counting bacteria is more precise than the streak plate method, but, on the average, it will. The streak plate method is a rapid qualitative isolation method for obtaining discrete colonies from a mixed population. Be sure to mix the nutrient broth tubes before each serial transfer.
Share contacts, email, files, and anything else needed to get the job done. Isolate single bacterial colonies by the streakplating method. Streak plate method streak inoculum onto one portion of the plate sterilize the loop streak through the first inoculum and spread into second section repeat several times incubate it for 24 h. Quadrant streak tips use the entire surface of the plate, not just the middle of the plate. Streaking is a technique used to isolate a pure strain from a single species of microorganism, often bacteria. Write the methods section concisely in paragraph format and in past tense. Streak plate technique is used for the isolation into pure culture of the organisms mostly bacteria, from mixed population. Secondly, only organisms that were viable in the original sample are able to be grown. We lighted a bunsen burner before the operation to make sure the whole streak plating is in sterile conditions. The modern streak plate method has progressed from the efforts of robert koch and other.
Different inoculation methods used in bacteriology. The lid of the agar plate has to be opened just sufficiently enough to streak the plate with the inoculation loop. Maintenance of bacterial strains university of missourist. This uses either the three streak or four streak methods. Comparison of the pour, spread, and drop plate methods for. Research journal of pharmaceutical, biological and chemical. Marc is gray in color and have larger circles whereas m. One of the most important techniques you will learn this semester is how to streak for isolation. The streak plate method is a way of sterilizing media. Firstly, users will not be able to grow obligate anaerobes using this method. Depending on the source of the sample used there might be thousands, millions or even billions of microorganisms per millilitre of sample. Streak the plate, following either the tmethod or quadrant streak shown below. Maintenance of bacterial strains university of missouri.
The spread plate is designed to create a lawn of the microbe evenly across the plate. After removal with bacteria on the loop, the quadrant streak method was used. What links here related changes upload file special pages permanent link page. Streak plates lead a scientist toward a pure culture for identification or examination of a single bacterial strain. This allows for individual colonies to be isolated from other colonies. Immediately streak the inoculating loop very gently over a quarter of the plate using a back and forth motion see area 1 in the figure above. A streak plate allows the scientist to study many microbes on one medium. On the mixed colony plate you can tell the difference because the s. Streak plates and spread plates to obtain single colonies. It is maintained by it services and the office of the cio. Compare the advantages of pour plate method over streak. Streaking culture plates in bacteriology slideshare.
Compare the advantages of pour plate method over streak plate method for the isolation of colonies of each organism top answer the pour plate and the spread plate methods are techniques used in the laboratory to determine the number of microorganisms. The drop plate method was preferred because of its economy in materials and labor. Streak the inoculated portion of each plate with a sterile loop to provide areas of heavy growth, and incubate the plates for 24 hrs 4. Ptak and ginsburg12 also listed these advantages for the streak plate method and showed that for the same samples. These colonies were then grown on nutrient agar plates by quadrant streaking technique to obtain. Some individual bacterial cells are separated and well spaced from each other. Advantages and disadvantages of streak, spread and pour. Individual colonies were identified from the spread plates, based on their. The main difference shall be how far the plate is turned during each streak. Use pourplating and spreadplating methods to determine the concentration of bacteria. Basic practical microbiology why microbiology matters.
Pick an isolated colony from the agar plate culture and spread it over the first quadrant. Essential methods for maintaining, preparing and using cultures obtaining suitable cultures 18 pure cultures 18 maintaining stock cultures 18. Do not touch the rim or inside of bottle, or petri dish. As you might guess, the purpose of streaking for isolation is to produce isolated colonies of an organism on an agar plate. Set a streak plate flat on a table to perform a streak test. Streak plate 11 pour plate 12 using a spreader spread plate 14 working with moulds 15 incubation 16 in conclusion. When convenient, pouring the petri dishes a day or two before using is a good idea the surface is easier to streak. The most common method of separating bacteria cell on agar surface to obtain isolated colonies is the streak method to inoculate petri dish. It provides a simple and a raid method of diluting the. In essence, the streak plate technique is a type of dilution. In microbiology, streaking is a technique used to isolate a pure strain from a single species of microorganism, often bacteria. Streak plating is a microbiology laboratory method that has two major disadvantages. Mb 230 laboratory syllabus winter 2018 lab sections. The following 41 files are in this category, out of 41 total.
Thus, the key difference between inoculation and incubation is that inoculation is. Going back to the edge of area 1 that you just streaked, extend the streaks into the second quarter of the plate area 2. The quadrant streak method see the article on quadrant streaking is good for obtaining wellisolated colonies. The pour plate method of counting bacteria is more precise than the streak plate method, but, on the average, it will give a lower count. With other hand lightly brush the loop back and forth on one quadrant of the dish. Remove only one colony or a barely visible amount of cells from a plate or slant. Request some of our most frequently asked for services in the academic technology category. For shortterm maintenance and use, it is best to streak bacteria on some type of rich agar petri plate, such as nutrient agar. Do not gouge into the medium with the loop and keep the lid over the plate as much as possible. Choose from 500 different sets of streak plate method flashcards on quizlet.
The streak plate was then incubated at 37 degrees celsius for 48 hours. Samples can then be taken from the resulting colonies and a culture can be grown on a new plate so that the organism can be identified, studied, or tested. A streak test is a method used to find the color of a stone or mineral in powdered form. The procedure is as for the spread plate but fewer plates are needed because. For these reasons, streak plate technique is widely used in laboratories pommerville, 2010. Cooled, but still molten, agar medium in a test tube or bottle is then poured into the petri dish. If no growth is detected after 24 hrs, continue incubation for an additional 24 hrs. In a pour plate, a small amount of inoculum from a broth culture is added by pipette to the centre of a petri dish. Compare the advantages of pour plate method over streak plate.
The links on this page provide the virtual microbiology classroom documents, web pages and videos useful in preparing for this lab. The streak plating method we used is shown as in graph 1, which is called the t streak. The streak plate method can be timeconsuming, especially if you are going to prepare a large sample size. The purpose of the streak plate is to sample and isolatedilute the bacteria into individual colonies what is the purpose of the streak plate. In microbiology, streaking is a technique used to isolate a pure strain from a single species of.
When attempting to isolate a specific type of bacteria from a clinical sample, this streak plate technique will need be repeated, possibly several times, in order to obtain a pure sample. Home basic microbiology streak plate method principle, methods, significance, limitations. Welcome to microbugz streak plate method of isolation. When convenient, pouring the petri dishes a day or two before using is. Apr 19, 2020 set a streak plate flat on a table to perform a streak test. Samples can then be taken from the resulting colonies and a microbiological culture can be grown on a new plate so that the organism can be identified, studied, or tested the modern streak plate method has progressed from the efforts of robert koch and other. Streak plate method principle, methods, significance.
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