Many thanks for the suggestion Dr. Goris

The size of bacteria is 1 micro meter . its better to use 3000 to 4000 rpm for 3 mins at 10'C. İts also depend on which phase you are going to harvest or time of culture.

I will harvest in the exponential phase.

Than use above parameters.

Thank you Sandeep...

Hi

3000 g, 5 min

Many thanks Bahar

It also depends on volume of culture

6000rpm for 5 minutes in table top centrifuge for 1.5ml culture

I need to harvest 1 ml, 10 ml and 100 ml of bacteria culture. So I think it s not a good way to use the same conditions for all volumes.

Dear Ilknur,

Five minutes for 1-1,5mL at 5000rpm should work. For larger volumes, you could use 10 to 15 minutes at 4000-5000rpm.

Dear Cristian,

many thanks for the suggestion

I prefer 8000 rpm for 3 min to harvest bacterial cells from 1-2 mL. If you reduce rpm you can compensate by increasing spin time.

10000rpm for 2 min sufficient

Bacteria harvest by centrifuge was dependent cell size but , general using 8000 rpm /5 min or 5000 rpm / 10 min please sent me bacteria type or bacteria name and I sent you the exact answer

8000 rpm for 2min. (1mL); 8000 rpm for 10 min. (10mL); 8000 rpm for 20-30 min. (100mL).

Good Luck

Centrifugation technique varies based on the end usage of the resulting pellet. Use of high RPM will disrupt the cells and may make the resulting pellet unusable for further use. 5000 RPM is better for pelleting bacteria without any cell disruption or damage. It depends on the type of bacteria. To make sure the viability of the resulting pellet, you can go for plate count if required.

Many thanks for all suggestions. I m very appreciate you all.

Dr. Niamah, bacterias are Morganella and Photobacterium strains.

I m very appreciate you all. many thanks for the suggestions.

I also would like to be sure, is it correct to use PS (0.85% NaCL, 0.1% Peptone) for the dilution of cell after harvesting. Some people suggest just saline solution (0.85%). Is there a big differences between them? What should I use for the dilution?

I used 0.85% of NaCl and Phosphate buffer by separately for bacterial soil, better results with NaCl

Perharps could be useful for you dos Santos, AL &Casper P. Different methods for extracting bacteria from freshwater sediment and a simple method to measure bacterial production in sediment samples. Journal of Microbiology Methods. Aug;41(3):249-57

Dear Jazmin, many thanks for your help.

5000 RPM is better for pelleting bacteria without any cell disruption or damage as Centrifuge process may lyse the cells due to the high speeds.

4000 rpm for 10 min is suitable for the pelleting of the bacteria cellls without cell lysis or damage.

I would prefer to use 8000 rpm for 10 minutes. Any higher speed than this would bring down other debris also. Lesser speed no doubt will pelletize the bacteria, but sometime we also need some partially autolyzed cells too. This is so if one is working with certain endo enzymes. Otherwise the yield will be erroneous. However, it all depends on what is your requirement of the cell pellet.

I always use 5000 rpm max 20 minutes, but 10 minutes is also sufficient. Have not had any problems so far.

most of the protocols suggests 5000 rpm for 10 mins.

5000rpm 8mins for most cases

5000r/min for 10min is suitable for harvesting bacterial cells without cell lysis or damage.

Why you want to centrifuge them? For cell lysis after or other use? If you want to lysis them, you can filtered the fermentation broth by using vacuum pump with 0.22um filter membrane, then wash the filter membrane with PBS (0.85% NaCl wtihin).

Use of high RPM will disrupt the cells but this sensitivity vary for different bacterial species. The speed of 4000-6000 rpm for 10-15 min is generally considered as a moderate range for sensitive strains. Hope it should also work well with you. If you want to standardize that, you should follow different combinations of speed & time and optimize for your bacteria depending on their survivability after pelleting by growing them on selective media.

Best wishes!

Dear all,

Many thanks for the all valuable suggestions.

Best regards,

Ilknur

I am usually using 5000 rpm for 10 min

Don't forget it also depends upon the radius of the rotor and length of the tubes. So conditions that might work for a micro centrifuge tube in a small rotor machine are very very different than pelleting cells in 500ml bottles in a very large radius swinging bucket rotor.

Michael is absolutely right. Really depends on what centrifuge/rotor/tubes you use. I harvest bacteria and yeast (in wines) using Eppendorf centrifuge, 1.5 ml tubes, 13.2 rpm for 5 min. Never saw any damage to the bacteria.

sorry, 13.2 krpm

Thank you very much for your good suggestions Dr. Benedik, Dr. Schulz and Dr. Garderes

Bests

you can as well check out 7500rpm for 3mins, it all depends on centrifuge and rotor.

6000rpm for 5minutes is more than enough and cells will not get any damage at that speed

5000 rpm for 10 minutes is enough to pellet bacterial population.

 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3255633/

I agree with Alla Fahim Abbas. However, I would like to add that if you do not want to miss out on any cell then you may very well spin at 8000 rpm at 4C for 15 minutes. 

The recommended g or the RCF value for harvesting bacteria is 5000 g for 15 min at 4 degree. You can convert g to rpm value if required by putting radius of the rotor in millimeters into the formula 

g = 1.12 × r x (rpm/1000)2

The protocols must express the values in gravities since the rpm changes from one rotor to another. Generally between 5000 and 10000g between 10 and 15 min should be enough. This will depend on the step in question

regards

Hi:

In order to pellet cells, people usually use around 5000 g (centrifugal acceleration 5000 times the gravity on earth) for 10 minutes.

Regards

5000 rpm for 10 min would be ideal..

Keep in mind that the speed and time required to precipitate anything depends on the density and not on the size of the particles. 5000 to 10000 x g for at least 10 min is good for bacteria especially if you want to retrieve them to make a plasmid prep.

Tube cracking is dependent upon the type and material of the tube. Filling tubes up to the top usually reinforces the resistance to cracking and collapse.

Check maximal allowed centrifugation speed (in g not rpm !) for the tubes you plan to use and the maximal allowed speed (in rpm) for the rotor and the buckets (if swinging buckets are used).

5000 g for 10 - 15 minutes works well.

In our laboratory I usually harvested Aeromonas hydrohila with 10,000 rcf for 10 mins and results were awesome!!

5000 rpm for 10 minutes

I usually go for 10,000Xg for 5 minutes for any protocol that needs cell lysis later on. But when the bacteria is desired to be cultured again such as in the protocols of bacterial transformation I prefer 2000 to 3000Xg. As higher rcf would damage the cells.

5000 x g for at least 10 -15 min is suitable for bacteria

in my experience i usually do 8000 rpm for 3 minit.