Selection of microbial populations degrading recalcitrant hydrocarbons of gasoline by monitoring of culture-headspace composition

A methodology was devised and was found useful for the selection of populat ions degrading recalcitrant hydrocarbons. The work was part of a programme aiming at developing knowledge of the intrinsic capacities of autochtonous microflorae of the environment for gasoline biodegradation. The methodology involved monitoring the progress of degradation in enrichment liquid cultu res on the selected hydrocarbon by gas chromatographic analysis of CO2 prod uction and O-2 consumption. Populations degrading in particular o-xylene, 1 ,2,4-trimethylbenzene, cyclohexane were obtained. Concerning 2,2,4-trimethy lpentane (isooctane), one microflora (and a pure strain derived from it) gr owing on this hydrocarbon were obtained from gasoline-polluted water.