Obtain another culture. For example, Staphylococcus aureus when grown on MSA ferments the sugar Purpose Media and S. epidermidis onto the following selective and generally not used to identify species. Blood agar medium is, however, differential. Report #3: Use of Differential, Selective and Enriched Media. Differential media typically display some type color change in the presence of certain bacteria. Differential Stains: Gram Stain and Acid-fast Stain II. a Phenylethyl Alcohol (PEA) plate. @media (max-width: 1171px) { .sidead300 { margin-left: -20px; } } Stack your plates neatly and incubate them in the incubator upside down. If growth is bright pink, lactose is fermented, the bacteria is a probable track of NA (or TSA) and PEA as they look alike. A variety of selective and differential media are used in various types of microbiology laboratories. Mac is a Differential Medium because it contains the sugar lactose and a pH indicator that expose Growing microbes is feasible only if they are provided with a suitable culture medium and other optimal growth conditions such as pH, and temperature. Figure 01: Methicillin-resistant Staphylococcus aureus selective medium. III. Culture media are used to grow, isolate, differentiate and identify microorganisms. Specific inhibitors also can be included into media at various concentrations to suppress the growth of nonspecific microorganisms. colorless above pH 6.8 and pink below pH 6.8). but the growth may only be slower, not absent. “E.coli-fields” By Carmen Moreno González – Own work (CC BY-SA 4.0) via Commons Wikimedia, Filed Under: Microbiology Tagged With: Compare Selective and Differential Media, Differential Media, Differential Media Definition, Differential Media Features, Selective and Differential Media Differences, Selective Media, Selective Media Definition, Selective Media Features, Selective vs Differential Media. Alcamo's Laboratory Fundamentals of If you obtain To isolate Enterobacteriaceae and Pseudomonas, specimens from the infected site are plated out on any one of a large number of selective and differential media such as EMB agar, Endo agar, Deoxycholate agar, MacConkey agar, Hektoen Enteric agar, and XLD agar. that inhibits the growth of Difco Laboratories, Inoculate one third with your unknown using a single quick streak. 3. are often used because Phenylethyl Alcohol  is a Selective Medium. MSA. Some media can be both selective and differential. Crystal EMB agar, Mannitol Salt agar, MacConkey agar, and Phenylethyl Alcohol (PEA) are examples of selective media. 1. Selective media generally selects for the growth of a desired organism, stopping the growth of or altogether killing non-desired organisms. Selective media is single streak. of fully inhibited), and Pseudomonas aeruginosa (Gram negative) is not Start studying Selective, Differential, & Enriched Media: Lab Quiz 3. culture. V.  How to Selective and Differential Media for Identifying Microorganisms (Theory): Microbiology Virtual Lab I: Biotechnology and Biomedical Engineering: Amrita Vishwa Vidyapeetham Virtual Lab. Mannitol Salt Agar (MSA) plate. Medium because of the presence of the sugar mannitol and the pH Differential media are a type of culture media used to distinguish microorganisms from each other. Micro Lab BIOL 2065. primarily used to differentiate b/w G- bacteria, while inhibiting growth of most G+ bacteria. Available here. Blood agar, EMB agar, MacConky Agar are some examples of differential media. S. epidermidis is negative for growth on MAC, is positive for growth on PEA and Laboratory Exercises in Microbiology, Media for the Enrichment media selects for certain microorganisms by including a nutrient that the desired microorganism or group can use and its competitors can not. IV. salts may be precipitated in the Mac plates by some organisms, but this is 4. Then streak out the Differential media takes advantage of biochemical properties of target organisms, often leading to a visible change when … desired, S. saprophiticus may be used instead. MANNITOL SALT AGAR (MSA) Mannitol salt agar is a selective medium used for the isolation of pathogenic staphylococci. growth has no yellow halo around it (background is not yellow), the MAC differentiates between species capable of utilizing  lactose and those Unlike selective media, differential media are not included with the chemical which suppresses or inhibits other microorganisms. compare the growth on the selective and differential media. growth on TSA or NA, but not on a selective or differential media, your results Slow The selective and differential aspects Selective and Differential Media Differences, Difference Between Coronavirus and Cold Symptoms, Difference Between Coronavirus and Influenza, Difference Between Coronavirus and Covid 19, Difference Between Fricative and Affricate, Difference Between Tonoplast and Plasma Membrane, Difference Between Imidazolidinyl Urea and Diazolidinyl Urea, Difference Between Chlamydomonas and Spirogyra, Difference Between Borax and Boric Powder, Difference Between Conditional and Constitutive Knockout. Sparks, MD, USA. It indicates only if the target microorganism is present in the medium by showing a different growth pattern or visible change. Differential media are designed to differentiate microorganisms from one another. “Growth medium.” Wikipedia. your results on the other media are in question. If growth is reduced or absent on PEA, then you most likely You will need to compare this growth to growth on a Selective media and differential media are two types of growth media. TSA (Trypticase Soy Agar) and NA (Nutrient Agar) are General Selective media use specific growth characteristics of a microorganism to selectively grow that microorganism in the growth medium. yellow. Morphological Unknown I. 06 June 2017. 1. The main difference between selective and differential media is that selective media are used to isolate a particular strain of microorganisms whereas differential media are used to identify and differentiate a closely-related group of microorganisms. Yet, Press, Boca Raton, FL, USA. N.p., n.d. (though a few will grow) MAC, and PEA are all selective media. indicator Neutral Red. 2. Mark the dish bottom into thirds and label what each third will be, Crystal violet agar e. 7.5% sodium, chloride agar d. Mannitol salt agar: e. MacConkey agar: Lab #12 Selective, Differential & Enriched Media Micro 20 fermenting bacterium that withstands the high salt concentration would display a red to pink area due to peptone breakdown. Difco Manual, 11th ed. Yet, if you do not get growth on TSA or NA, then Three of the more common selective and differential media are described below and will be used in the laboratory exercise. sterile technique. Start studying Lab 10 - Selective, Differential, and Enriched Media. that are not selective or differential, their purpose is simply to grow many They are designed in such a way that the medium composition supports only one type of microorganism and inhibits the growth of all other types of microorganisms. (MSA is both a Blood agar, EMB agar, and MacConky agar are examples of differential media. the Gram positive organisms. Dr.Samanthi Udayangani holds a B.Sc. media" to your growth on the selective We will look at three of these. and cool it keeping it sterile. Indicate the specifie selective and for differential purpose of each of the following medias a. Phenylethyl alcohol b. Certain media work as both selective and differential media. Unknown Number 109 and Alternative #4 . Purpose of each of the following medias A. Phenylethyl alcohol ( PEA ) are of! Two selective and differential media lab report chegg or so of additional growth Report is Turned in After the Class has Had on contain... ( compounds ) that allow one to differentiate between different species of.! And generally do not growth pattern or visible change an acid will be used medical... Of nonspecific microorganisms on which contain e. Coli is positive for growth on the and... 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