Theory of Staining Techniques

977 WordsOct 15, 20094 Pages
Theories of Staining Techniques Staining bacteria with different dyes via staining techniques, allows in distinguishing the microorganism from its backgrounds. Also, helps in studying different internal structures such as vacuoles, cell walls and spores in details (Seeley and others 1991). Some staining techniques such as Gram staining, endospore stain and capsule stain are some of the theories of stains used in bacteriology today. Also, these staining procedures help in determining properties of an unknown culture. Gram staining is a differential stain that helps in distinguishing between types of bacteria and it is the most useful staining procedure used today (Seeley and others 1991). In this kind of staining procedure, a basic…show more content…
However, a normal observation of an endospore staining would have “green stained endospores and the rest of the cells without endospore cells” (Seeley and others 1991). In addition, if a simple stain is used, the spores will appear clear because the walls of endospores resist stain penetration (Black 2005). FIG II A different kind of stain is the capsule stain. In this staining procedure, the capsules in a cell are not stained intensely because they vary in thickness and can repel stains (Seeley and others 1991). Congo red is the primary stain in this procedure, which stains both bacterial cell and the surrounding capsule (Seeley and others 1991). To start off, place several loopfuls of unknown culture in Congo red solution on a glass slide. Then, allow the slide to air dry. However, do not heat-fix as noted in the above two staining procedures. Next, flood the smear with Maneval’s stain for at least 1 minute, then rinse with water and blot dry. Following that, observe the slide under the oil-immersion objective and record any findings of the capsules unstained ad blue or black backgrounds. After observation of the slide, the capsule stain of the unknown culture appeared unstained with a blackish background and the cells were reddish brown and they were large and arranged in pairs, which indicates that there is presence of some bacterial
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