https://padlet.com/aishahhanapi/microbialPreservationTechniques Experiment 7 Principles of Microbiology CBB 20003 en-us 2018-10-28 15:26:31 UTC 2025-04-22 16:02:15 UTC hello@padlet.com https://padlet-assets.s3.amazonaws.com/icons/File.png aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297762876 PART A

1. 500 μl of sterile 30% glycerol was aliquoted into sterile micro-centrifuge tube.
2. 500 μl of bacterial culture was added to the tube and mixed with the glycerol.
3. The tube was labelled and placed in the freezer (20 °C).

PART B

1. A small volume of culture was removed from the tube to activate the bacteria. 
2. Small volume of frozen/thawed cells was transferred to an agar plate and streaked.
3. The viability of the culture was observed after 24 hours of incubation at 37 °C.]]> 2018-10-28 15:33:01 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297762876 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764403 Apparatuses needed for the experiment]]> 2018-10-28 15:46:41 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764403 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764505 Small volume of culture was taken from the tube.]]> 2018-10-28 15:47:43 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764505 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764538 Flaming of the inoculating loop as aseptic technique.]]> 2018-10-28 15:48:03 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764538 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764602 Streaking of the culture on the surface of nutrient agar.]]> 2018-10-28 15:48:42 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764602 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764693 Labelling of the agar plate.]]> 2018-10-28 15:49:31 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764693 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764695 The microbial was incubated in an incubator.]]> 2018-10-28 15:49:33 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764695 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764982 From the result of this experiment, it can be concluded that this experiment achieved its objectives as the preservation of microbial species E.coli and B.subtilis was successful. 

This is because, after around 2 months of preservation, the cells were able to be activated and grown.

This proves that microorganism can be preserve so that the death rate is reduced when the culture is revisited and some cells are still viable and can be used for culturing purposes.

In this experiment, preservation of microbial was manipulating the rate of deleterious reactions in a culture of bacteria by lowering the temperature of the surrounding. This will decrease the rate of all chemical reactions and can be done by using refrigerators, mechanical freezers and liquid nitrogen freezers. The bacteria was frozen using glycerol in which 30% diluted glycerol was mixed with the same amount of culture broth before frozen.]]> 2018-10-28 15:52:02 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297764982 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297765399 Bacillus species preserved was activated as the growth can be observed from the colonies grown.]]> 2018-10-28 15:56:00 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297765399 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297765448 The E.coli was seen growing on the agar.]]> 2018-10-28 15:56:22 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297765448 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297765484 Another E.coli taken from another tube was also seen grown.]]> 2018-10-28 15:56:42 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/297765484 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/301312843 Microbial preservation techniques are done as most lab might need numbers of variations of individual bacterial cultures anytime. Thus, preservation is necessary to slow down death rate of a bacterial culture so that it can be used for culturing. 

Otherwise, though the culture may be healthy initially, the number of viable cells will decrease to zero as time passes. There are many reasons as to why bacterial cells can die but it is usually because of the inherent chemistry of the cells and their environment. 
 
Thus, their environment may be altered so that the deleterious chemical reactions can be slowed or halted to result in overall viability of the culture for longer time period.]]> 2018-11-07 02:55:02 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/301312843 aishahhanapi https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/301312904 1. To perform microbial preservation techniques on the microbial
2. To prove the viability of microbial after preservation]]> 2018-11-07 02:55:28 UTC https://padlet.com/aishahhanapi/microbialPreservationTechniques/wish/301312904