Membrane processes bioactive compounds from

Membrane Processes in the Separation, Purification, and Concentration of Bioactive Compounds from Fermentation Broths... 

So far, SAR studies for P-gp have been performed on the basis of classical QSAR principles which were designed for transporters or receptors, which naturally bind one specific substrate from an aqueous environment. The assumptions made are that (i) the modeled conformation is the bioactive one (ii) the binding site and/or mode is the same for all modeled compounds (iii) interactions between the drug and the binding site are mainly due to enthalpic processes (e.g., van der Waals interactions) and (iv) solvent or membrane effects are negligible (cf. Ref. [35]). 

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