SURVIVAL OF CANDIDA-ALBICANS AND PSEUDOMONAS-AERUGINOSA IN OIL-POLLUTED TROPICAL COASTAL WATERS

The effect of environmental abiotic factors on survival and activity o f oil degrading isolates, Pseudomonas aeruginosa OD-1 and Candida albi cans OD-2, was determined in situ using membrane diffusion chambers. T he study sites were located in a tropical bay on the Atlantic Ocean wi th history of petroleum contamination by oil tankers. Microbial densit ies were measured by direct counts. H-3-thymidine uptake, microautorad iography, INT-reduction, adenosine triphosphate (ATP), and frequency o f dividing cells were used to assess microbial activity. Both organism s showed a significant decrease in cell density over a three day perio d, although, temporal increases in densities were observed. Significan t decreases in total activity vr;ere observed ibr both populations dur ing the study; however, the respiration potential and ATP content per organism remained constant or even increased by the end of the study s uggesting that a significant fraction of these populations were capabl e of withstanding in situ environmental conditions. Results suggest th at increases in ambient phosphorus concentrations played a role in the prolonged ill situ survival of these petroleum degrading isolates at some sites. The traffic of oil tankers might have played a significant impact on microbial survival in this bay, as violent agitation of sed iments increased phosphorus concentrations available to microorganisms . Published by Elsevier Science Ltd.