This medium is recommended as a general purpose medium for cultivation of wide variety of organisms and for inactivation of penicillins, cephalosporins of first, second, third and fourth generation and penems. Lecithin and polysorbate 80 neutralizes quaternary ammonium compounds and parahydroxy benzoates. β lactamase mixture added in the medium will inactivate the β-lactam antibiotics thus enabling recovery of organisms from the environment of cleanrooms where production of antibiotics is carried out.