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The environmental effects of adding certain selected petroleum products to field soils at widely separated geographical locations under optimum conditions for biodegradation were studied. The locations selected for study of soil biodegradation of six oils (used crankcase oil from cars, used crankcase oil from trucks, an Arabian Heavy crude oil, a Coastal Mix crude oil, a home heating oil no. 2, and a residual fuel oil no. 6) were Marcus Hook, Pennsylvania, Tulsa, Oklahoma, and Corpus Christi, Texas. The investigative process, covering a period of 1 year at each location, was conducted in 14 fields plots (1.7 by 3.0 m) to which

A soil isolate identified as a strain of Nocardia corallina accumulated a , a'dimethyl-cis, cis-muconic acid under co-oxidation conditions employing n-hexadecane for growth and p-xylene as the co-oxidizable substrate. N. coraifina V-49 was postulated to have two pathways for the oxidation of p-xylene. One pathway proceeds through p-benzyl alcohol, p-tolualdehyde, and p-toluic acid to 2,3dihydroxy-p-toluic acid, and the other pathway results in ortho ring cleavage of 3,6-dimethylpyrocatechol and hence accumulation of a,a'-dimethyl-cis,cismuconic acid.

This review summarizes the present status of hydrocarbon cooxidation in microorganisms. Hydrocarbons, which cannot be used for growth by many soil microorganisms, can be oxidized if present as co‐substrates in systems in which another substrate is furnished for growth. Paraffinic, cycloparaffinic and aromatic hydrocarbon cooxidations have been demonstrated. Most hydrocarbon cooxidation reactions seem to involve the incorporation of molecular oxygen by mono‐ and dioxygenases. From paraffinic hydrocarbons, products accumulating in fermentation systems include acids, alcohols, aldehydes and ketones. Usually, the initial attack is at the terminal methyl group in paraffin oxidations. The only products isolated in the cycloparaffins have been ketones. Extensive studies have been carried out on cooxidation of mono‐ and dicyclic aromatic hydrocarbons. Oxidation of methyl substituents on aromatic rings usually results in the accumulation of the aromatic mono acid or alcohol. Dihydroxylation of the aromatic ring has been observed. Products of aromatic ring rupture arise via both ortho and meta cleavage pathways.