ABSTRACT
Polyhydroxyalkanoate [PHA] from one fermentation process shows diverse physical properties when extracted using different methods. Pseudomonas aeruginosa strain has been previously isolated from the Egyptian ecosystem was cultivated on olive oil as a carbon source under PHA accumulation conditions. PHA was extracted using four different extraction methods and the polymer give different biological properties. Leucocytes grown in different rate on each preparation. RBCs haemolysis test was used to determine the polymers toxicity. PHA isolated directly with chloroform give the highest leucocytes number [19.4 10 4 Cells/48 hr] and the lowest Haemolytic index [2.28]. Bioassays used in this study are recommended for evaluating the in vitro polymer biocompatibility aiming to in vivo application or as a cell line-supporting matrix