Abilities of Achyla orion and Allomyces anomalus to degrade petroleum and petroleum products as sole carbon sources

Abilities of Achyla orion and Allomyces anomalus isolated from some crude oil polluted aquatic environments in Nigeria to biodegrade petroleum and petroleum products were determined. Baiting method using hemp and sesame seeds was used to isolate the two species of aquatic phycomycetes. The species were grown in liquid broth culture made of minimal mineral salts supplemented separately with petrol, diesel and kerosene and incubated at room temperature with agitation for two weeks. Biodegradation was monitored using spectrophotometer at 600 nm wavelength. Fat/lipid was extracted from pellets resulting from centrifugation of the final broth culture using selected fat extractor and quantified. A. anomalus gave highest mean growth values in broth medium supplemented with diesel (0.970) and kerosene (1.302) while that supplemented with petrol recorded the least mean growth value of 0.663. The mean growth values for A. orion showed a similar trend. Crude fat/lipid production was highest for both isolates grown in diesel supplemented broth culture medium and least for both isolates grown in petrol supplemented broth culture medium. These results imply that these two species of aquatic phycomycetes were able to degrade diesel and kerosene better than petrol with corresponding production/accumulation of fat/lipid as biodegradation product.   Key words: Aquatic phycomycetes, petroleum, fractions, mineral salt and supplement.