Conventionally 1% (V/V) inoculum means 1ml inoculum added to 99 ml medium. This method does not ensure same initial optical density (OD) in the inoculated medium due inherent variations in OD of the inoculum from batch to batch. Instead of fixing inoculum volume, transfer that much volume of inoculum based on its OD which gives an optical density of about 0.1 in about 100 ml inoculated medium (99 ml+0.8 to 1.2 ml}. This will not cause significant change in final medium volume after inoculation. This will ensure that the initial starting OD of the medium is practically remains the same. This way you can ensure reproducibility in fermentation time. You can calculate it approximately by using a simple equation: Volume of inoculum= 0.1 OD*100ml/OD of inoculum.
Dear sir for preparation of 1% bacterial culture first of all prepare bacterial broth culture and then after in 99 ml new broth medium inoculate 1ml cultured sample.
For 1% bacterial culture preparation, I took approximately 10 microlitter from 10 ml of the broth culture or one loopful from the single bacterial colony on agar medium of the logarithm growth phase of bacteria to new broth medium.
Conventionally 1% (V/V) inoculum means 1ml inoculum added to 99 ml medium. This method does not ensure same initial optical density (OD) in the inoculated medium due inherent variations in OD of the inoculum from batch to batch. Instead of fixing inoculum volume, transfer that much volume of inoculum based on its OD which gives an optical density of about 0.1 in about 100 ml inoculated medium (99 ml+0.8 to 1.2 ml}. This will not cause significant change in final medium volume after inoculation. This will ensure that the initial starting OD of the medium is practically remains the same. This way you can ensure reproducibility in fermentation time. You can calculate it approximately by using a simple equation: Volume of inoculum= 0.1 OD*100ml/OD of inoculum.
I agree with the answer given by V. Sahai Sir..................there must be a fixed cell density of overnight grown culture and 1% volume must be added in say 100 ml.
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