University:
Swansea University
Course:
PM134 | Microbiology
Academic year:

2023
Views:

291

Pages:

3
Author:

Sanjeev KG

Expt. No Date 10/3/23 Page No 3 GRAM STAINING AIM To differentiale gram positive of gram negative bacterin which was is dated from air comple. PRINCIPLE when the bacteria is stained with primary stain Ouptal vedet f lized by int mordant, come of the bacteria are able to retain the primary stain if some are devdavenged by alcoholtre all walls of xam positive bacteria have a thick layer of protein sugar complexus called Peptidoglycan I lipid content is low. Derdourizing the wel Cauks thick cell wall to dehydrate af shrink which clous the pores in the cell wall of peevents the stain from exiting the cell. So the ethenod cannot semove the aystal videtiadine complex that is bourd to ene thick layer of peptidoglycan of geam pesitive bacteria Ef appears blue a preple in colour. In case of gram negative bacteria, ull wall also takes on the CV- lodine complex but due to thin layer of reptidoglycan of thick outer layer which formed of lipids cv-iodine complex gees washed off When they are exposed to alcohol devdouriger dissolves the lipids in cell walls, which allows the CV-ioding complex to leach out of the alls then when Hained with sapanin, they take the Hain af appears hed in colour' MATERIALS REQUIRED Oujital videt, beam's jodine, Ethyl alcohol caeanin, glass slide minoscope inoculation 100p. Diste Fapt No PROCEDURE Take a lian grass wirde xerele technique Trence smens by Nourg a deep w on ene side, men teansferring the culturs seperately to the desp of writes ses a steelle, wed loop 2 Mix of spread organisen by means of autular motion of the irculating loop 4 slow smears to are-dey y then heat for • bently flood meals with aystal under of let stand the I mineche intly wash with tap unter af gently Hood the areas with Exam's jodine mordant I let stand for iminute boritly wash with tap water. Toulousize with 75% chyl alkohol. Do not over declaring Add agent deep by drop until the alcohol suns almost chat, showing only a blue linge. 9. Gently wash with tapwates seconde Countesslain wich cafeanin tor 45 10 Gently wash with tap water if air day of examine under oil impression objective. OBSERVATION The colonies grown in plate found to be gram positive rads with and without sanitizer uns under 100x milloscope The colonies goun air for 10 ming. 100x mivoscope. on plate was saind nae cous expared to oxusmulal to be gearn negative cocci Under RESULTS Minobial growth was observed as colonies when grawn in plater with of without sanitiger as well at plate which w exposed to orteameal air for 10mintal giam straining was dore. 17/3/25