my feeling is that swirling simply stops the cells from sinking to the bottom under gravity then all of the growing cells will layer in a band of medium which will become depleted locally. Mixing ensures that all of the cells are surrounded by fresh medium all of the time. In short there is nothing special about 180 or any other value so long as the cells are kept in suspension any reasonable speed which does not cause foaming will be fine

Paul is correct ... but still if you want I think  you could increase surface area by decreasing culture volume .. generally people take 1/3  of culture media in a flask  ... instead you could  take less media .. if you want the similar effect... 

look answers in following question :

https://www.researchgate.net/post/What_would_be_the_proper_volume_of_LB_media_in_a_flask_for_optimal_aeration_and_thus_growth_of_Ecoli

All the Best

Paul is correct, but as the culture reaches higher density, oxygen becomes rate limiting for growth, and higher shaking speeds generally give better aeration. Of course E coli can grow anaerobically, so shaking speed depends on what you are using your cells for. If it is just plasmid isolation, practically any shaking speed that keeps the cells suspended is fine (just as Paul stated). However, if you are trying to grow phage, or express protein for isolation, then optimal aerobic growth may be more important. That being said, however, there is usually not much difference in aeration between 140 and 180 rpm. But certainly follow Prakash's recommendation that you use 1/3 or less of the flask volume for culture volume. I grew up in a phage lab and was taught that 1/10 of the flask volume was the appropriate culture volume, but I generally use 1/5 flask volume. 

best of luck!

I agree. Agitation and aeration are very critical steps in microbial fermentation. However, you can still decrease or increase the rpm from 180 depending upon the requirement of oxygen by the producer microbial strains. One can identify the optimum rpm for the growth producer microbial strains by optimization.

Guess bacterial growth is more affected by temperature fluctuations rather than the rpm of the shaker. I have experience of growing bacterial cultures where there is no provision to set the rpm of the shaker so basically under agitation is fine so that there is no film of bacteria created or it doesn't settle, also yes using 1/3rd the volume of the flask facilitates aeration and growth.

No problem, I usually grow bacterial cultures at 150 rpm, 30 C, it took little longer time. This condition is good for large size plasmids. You can grow happily at 140rpm!! All the best

If the purpose of shaking is to just getting bacterial mass, no problem. But if you are doing growth curve than the growth kinetic may change, however here I assume other parameters like temperature, media volume, pH all are not altered.

Hi Patel,

Thanks for your answer. Do you think the rate of cell division will be affected by the rpm of the shaker?

I am growing cells with plasmid inside.So, is it gonna affect the knockout procedure of the cells?

Technically, 150-180 rpm should not be a problem,but, if your protein needs oxygen for proper folding, you might need to increase the shaker speed. Erv1 needs oxygen and it is recommended to use 260 rpm . Having said that I think you can easily use 150 rpm provided your POI is not fastidious in nature.

Hi Abir,

I want to express a recombinant lipase. Will growing it at 190 rpm affects the expression and the viability?

Thank you.

Dear Abir,

Thanks for your answer. I wanted to know what do you mean by the fact that a protein might need oxygen for folding inside a cell. I'm not clear how the folding will be dependent on the oxygenation of the cells and how do you determine it? Was it reported that your protein needs more oxygenated environment to or you found out in your experiments?

Dear bro and sister, I'm a junior researcher and is doing a project as part of my thesis. I'm growing Non-typeable Haemophilus influenzae in BHI broth suplemented with glycrol, Beta NAD, and Hemin in 50 Falcon tube. I'm wondering whether i need to tighten the lid or loosen the lid when putting in an shaking incubator?

Thank All,

I have found in E. coli DH5@, around 230-250 rpm gives more growth than 180 rpm. People also grow at 300 rpm for 16-18 hrs. Shaking purpose is create a healthy aeration for culture.

According to Karim E. Jaén etc. BMC Biotechnology 2017 17:60, Microaerobic conditions have little effect on pDNA production, supercoiled fraction and sequence fidelity. Article Heterogeneous oxygen availability affects the titer and topo...

May i know with regards to the temperature, if there is a significant difference?

Synat Keam , Haemophilus Influenzae is a facultative anaerobe meaning that it is capable of growing anaerobically if oxygen is absent. However, it is more energetically favorable to grow when oxygen is present. Without oxygen, fermentation will take place. If you want to study the fermentation process, it will take a more optimized setup than just sealing the lid. However, if you loosen the lid and tape it to the tube (so the lid doesn't fly off in the shaker) then I would expect that you would get more growth.

If you measure the oxygen concentration in a half grown up culture of yeast or bacteria you will find that it is zero. Let me know if you find anybody else who actually measured it.

Purpose of shaking is for airation , for the aerobic growth of the bacteria. it also prevents the bacteria from settling down on the bottom of the tube. Though normally 150-250 rpm is the preferred range it can be increased upto 400 rpm for increasing the growth. However, when reducing the 'rpm' it is advisable to reduce the culture volume.

Shakers don't work. If you measure the oxygen in a culture of yeast or bacteria during growth -- you know, actually stick a Clarke-type oxygen electrode in there and measure the concentration of dissolved oxygen in the culture medium while you're shaking it -- or use those little noninvasive Pra-sens buttons from Germany -- you will find out that the oxygen concentration is zero. I know that because I measured it. The first time I did that experiment was in 1968. It is now fifty years later and nothing's changed. Everybody including everybody adding their Answers on this page are still shaking their culture vessels and ignoring the zero oxygen situation. Of course everybody can go merrily on ignoring the oxygen concentration in their culture vessels, but it's a strange kind of ignoring/ignorance where you simply do not measure it. It is unscientific, is what it is. Unscientific to simply not measure a parameter and just arbitrarily assume that it is not influencing your entire research programme to have thrown a monkeywrench into the physiology of your biological starting material. AS those two brilliant pioneering researchers said, so many years ago, Bill and Ted: "Party on, dudes!"

That was an interesting answer supra where the question was raised about whether oxygen in the culture medium affects the folding of a particular protein. Whoever was working on that would surely have had cause to wonder what the actual oxygen concentration actually was/is, no?

What is rpm for best growth of rhizobium ?

Well I think, if you need to reduce or increase the rpm, you will also need to alter the volume as against the normal 10-25% of the flask at 180rpm.

Did you measure the oxygen concentration?

Perhaps of some interest for your query:

https://www.researchgate.net/post/How_can_KLa_be_calculated_in_a_flask