wickedtaya.blogg.se

This one is another most commonly used method of Capsule staining. The Capsule of the bacterial cell appears as a clear halo around the stained bacterial cell body and the Dark background (color depends upon the dye used – India ink or Nigrosin). In this technique, two dyes are used that is Crystal violet and the India ink / Nigrosin. This one is the easiest method of capsule staining. NEGATIVE STAINING – INTRODUCTION, PRINCIPLE, PROCEDURE, RESULTS & APPLICATIONS The Two most commonly used methods are as follows:Ĭheck out the Negative staining technique

The result of the staining varies as per the Method followed but commonly all the methods have one thing in common that it stains the bacterial cell, capsule and/or Background. There are numerous methods available for the demonstration of the capsule in bacterial cells. whereas the background is stained best with the Acidic stains which include the India ink, Nigrosin, Eosin, Congo red etc.

The Bacterial cell body is stained best with the Basic stains like Crystal violet, Safranine, Methylene blue etc. The excellent way to demonstrate the capsule is to stain the bacterial cell body and the background leaving the bacterial capsule as colorless. A Bacterial capsule is non-ionic in nature, so there is no or very minute possibility that the acidic or basic stains will adhere to their surfaces so it remains colorless. However, the result varies as per the methodology used for capsule staining.įirstly, let’s discuss the bacterial cell structures which are involved in this staining technique and later on we’ll move to the principles involved in capsule staining technique.Ī capsulated bacterium acquires a capsule around its body which appears as a clear halo. Heat fixing is also avoided as it will destroy or distort the capsule which makes it more convenient and moreover the newbie’s to microbiology can easily do it and explore more in the microbial world….īriefly, in Capsule staining technique, the background and the bacterial cell body is stained whereas capsule remains colorless. There is no use of Complex processes and multiple strong reagents or stains in Capsule staining process and simplest methods like India ink method gives the satisfactory results so that we can easily determine the presence or absence of capsule in the bacterial cell. (adsbygoogle = window.adsbygoogle || ).push() Īlso, to get the better results and to enhance the size of the bacterial capsule a drop of serum can be used while preparing a smear which makes it more convenient to observe bacterial capsule with a typical compound/light microscopes. Most of the capsules are made up of polysaccharides but there are many which are composed of Polypeptides (Proteins).Ĭapsules are usually fragile and can easily be destroyed or distorted by heating so the capsule staining is designed in such a way that maintains the overall morphology of bacteria as well as preserved the Capsule structure so that we can easily identify it. When this secretion remains loose and un-demarcated it is called a slime layer and when it is organized into a sharply defined structure it is called as Capsule.

INTRODUCTION TO CAPSULE STAINING TECHNIQUEĪ capsule in bacteria is the result of amorphous viscid secretion released by the bacteria.