Try this. put primary culture in LB having 0.5 M Sorbitol @ 37 degree. then 2ndry culture in same type of media (LB having 0.5 M Sorbitol) + 1mM Betaine (if u have, it's very useful otherwise w/o this u can try) @ 37 degree. when OD600 reach 0.4/ 0.6, transfer the culture @ 42 degree waterbath wherein u shake the culture flask for atleast 30 min at constant RPM or by hand u can try this and when OD600 reach 0.8/1 induce with IPTG whatever molar generally u use (try 0.5 mM) and transfer the culture at 18 degree for over night. U will get ur protein in soluble fraction. Other wise u can try with glycine glycine method, a paper published from CCMB. just check that. 1st method try, u will get surely. all d best

@pradeep yadav,thanks for your kind suggestion. I tried to find CCMB glycine method protocol but couldn't. can u send me that paper or put that paper link here. I will be grateful to you dear.

Thanks