GROWTH PATTERN OF HYDROCARBON-UTILIZING ISOLATES IN CHEMICALLY DEFINED MEDIUM

El-Sayed, Abdel-Halim; Mahmoud, Wafaa; Davis, Edward; Coughlin, Robert

doi:10.21608/zjps.1994.169725

GROWTH PATTERN OF HYDROCARBON-UTILIZING ISOLATES IN CHEMICALLY DEFINED MEDIUM

Document Type : Original Article

Authors

¹ Department of Microbiology, Faculty of Pharmacy, Zagazig University, Egypt

² SymBiotech, Inc., Wallingford, CT, USA

³ SymBiotech, Inc. and Department of Chemical Engineering, University of Connecticut, Storrs, CT, USA

10.21608/zjps.1994.169725

Abstract

Adhesion of five different bacterial strains, isolated from oil-contaminated soil, on suspended droplets of Jet A fuel was different but not absolutely parallel to the observed growth rates of the strains on this fuel. Preconditioning to hydrocarbons as well as direct aeration of the culture medium significantly increased growth rates of the different strains. Jet-A fuel, and motor oil were found to serve as a source of carbon and energy for each of these strains. Conversely, brake fluid did not support growth of any of these strains. The growth of one strain Arthrobacter globiormis (SBI-5) on hydrocarbons predominated over the otther four. Growth of SBI-5 on Jet-A fuel or motor oil was accompanied by production of an emulsifying agent. Growth rate of SBI-5 was monitored by observing optical density (OD₅₄₆) and total protein in liquid cultures as well as reduction of 2,3,5-triphenyl tetrazolium chloride (TTC) to formazan in liquid and agar cultures. The latter measurements by colorimetry was found to be faster and simpler for screening biodegradation.