A simple and rapid semiquantitative slide catalase test useful for the identification of oxidative and nonsaccharolytic gram-negative bacteria, i.e., "nonfermenters," is described. Using the interpretative criterion of time of appearance of oxygen bubbles in 3% hydrogen peroxide, three categories of nonfermenters were established. The rapid catalase producers included Achromobacter xylosoxidans...

Four bacterial isolates were previously isolated from soil polluted with petroleum oil from Cairo Refining Company, Qalyubia, Egypt. These isolates (MAM-26, 29, 62 and 68) and standard strain Enterobacter cloacae MAM-4 were grown on five concentrations of pyrene (Pyr.) as a sole carbon and energy source. The abilities of these isolates to degrade Pyr. have been investigated. The growth (O.D) an...