It always generates clump for long-term culture of Mtb even in the presence of tween-80 or Tyloxapol.  you have to use syringe to disperse the clump into even suspension before use.

I agree with above. Although when I work with M. bovis, passaging the cells up to few times on the fresh medium with tyloxapol helps to get more even cell suspension. You should try that. When using needle passaging You have to be extremely careful due to the high aerosol production and there is always a risk of splitting or disconnection between syringe and needle (always use lure-lock syringes).

Best.

D.

You can use either Tween or Tyloxopol to limit clumping of mycobacteria. I have used both.

Both strip the capsule somewhat and reduce clumping, but like one comment says you should still declump using a physical method.

Thanks a lot. I have tried the above methods. But using syringe has given me better results but I am not still sure about the viability of the cells after syringe passage. I need to check it. But yes I have taken necessary precautions using syringe. I agree with Damien that passing the cells for few generations in presence of detergent gives less clump but still they remain clumpy. I will update if I get some good solutions regarding this problem. I am trying to mimic the way we see Mtb in sputum samples which is absolutely clump free (I presume). So I need my controls to me comparable enough visually with the sputum samples.