The use of extn. techniques to alleviate product inhibition in bioprocesses is one of a no. of potential sepn. methods. However, the intimate contact of an org. phase with the broth implies that the org. components of this phase may be present in the aq. phase at satn. levels. The quaternary amine Aliquat 336 (trioctyl/decylmethylammonium entity), dissolved in octan-1-ol showed no inhibition on the growth of Pseudomonas putida, at least with respect to mol. toxicity. Nevertheless, it is important to point out two main effects of Aliquat 336 assocd. with its ion exchange properties. It is able (1) to complex hydroxyl ions and therefore drastically lower the pH of the broth and (2) release its counter ion through these exchanges. Therefore, a strict control of the pH of the cultivation must be conducted, with the constraint that Ps. putida has an optimal pH growth of 7.4-7.5. The pH range tolerated by this strain is, however, between 5.0 and 9.0. In addn., the counter ion of Aliquat 336 needs to be carefully chosen and HSO4- should be preferred to Cl-. [on SciFinder (R)]