| Preparation Of Culture Suspension For Growth Promotion Test |
1.0 OBJECTIVE: 1.1 To lay down the Procedure for Preparation of Culture Suspension for Growth Promotion Test to determine 10-100 cfu by serial dilution method. 2.0 SCOPE: 2.1 This procedure is applicable for all the cultures used for Growth promotion test and other microbiology related analysis. 3.0 RESPONSIBILITY: 3.1 Microbiologist 3.2 Quality Control Head 3.3 Quality Control Officer / Executive are responsible to follow procedure as per the procedure mentioned in this SOP. 3.4 QC Head is responsible for implementation and compliance of the procedure as per this SOP. 4.0 ABBREVIATIONS 4.1 SOP : Standard Operating Procedure 4.2 LAF : Laminar Air Flow 4.3 PSI : Pounds per square inch 4.4 NLT : Not Less Then To Read this SOP Click here SOP for Handling of Out Sourced Activities. 5.0 PROCEDURE: 5.1 Take out the working cultures from the refrigerator 30 minutes prior to the testing so as to acclimatize with the working environment and place it under LAF in the culture handling room. 5.2 Red hot the loop and cool it, take a loop full of culture and inoculate it into 20 ml of sterile 0.9 % saline solution (initial suspension). 5.3 Gently vortex it so as to make a uniform suspension. 5.4 With the help of micropipette take 2.0 ml from the Initial suspension and inoculate it into 18.0 ml of 0.9 % saline solution (1:10 dilution). 5.5 Transfer 2.0 ml from the above dilution to another bottle containing 18.0 ml of the 0.9 % saline solution. 5.6 Perform the serial dilutions in the same manner ranging from 1:10 to 1: 100000000. 5.7 Perform the whole exercise with all the organisms, which are being used for growth promotion test. 5.8 Enumerate the culture organism by pour plate method and add 1.0 ml of the dilutions into sterile Petri plates. 5.9 Pour sterile molten Soyabean Casein Digest Agar to all the plates containing respective dilution for bacterial cultures and Potato Dextrose Agar to all the yeast or molds cultures into the plates. 5.10 Incubate the plates at 32.5 ± 2.5°C for 48 hrs for bacterial cultures and 22.5 ± 2.5C for 5 to 7 days for fungi. 5.11 Do not discard the dilutions after plating the cultures. Preserve the dilutions in refrigerator at temperature 2-8°C 5.12 After the specified incubation period enumerate the number of colonies. 5.13 Select the dilutions which are having cfu between 10 –to – 100 cfu / ml. 5.14 Preserve the dilutions which are having cfu between 10 – 100 cfu / ml in refrigerator for further tests. 5.15 Store the culture suspension for one week at 2-8°C. 5.16 Frequency of culture suspension preparation of bacterial and fungal cultures is once in a week. 5.17 Label the culture suspension with following details: 5.17.1 Name of the Organism : 5.17.2 Strain No. : 5.17.3 Concentration : 5.17.4 Prepared On : 5.17.5 Use before : 5.17.6 Prepared By : 5.18 Decontaminate the left over dilutions in an autoclave at 121ºC and 15 PSI for NLT 20 Minutes and discard. |
