ISOLATION AND CHARACTERIZATION OF PSEUDOMONAS PUTIDA PRODUCING BIOPLASTIC (POLYHYDROXY ALKANOATE) FROM VEGETABLE OIL WASTES

Abstract

The current study aimed isolation and characterization of local bacterial isolates capable of production Poly hydroxy alkanoate (PHA) using oil residues as a single carbon source. Many polluted environmental sites were used as sources of isolation of bacterial isolates. The collected samples were processed by serial dilution followed by spread plating in nutrient agar plates to get isolated colonies. Bacterial isolates were tested for (PHA) granules production using Sudan blank and Nile blue stains, nine of fifty isolates could produce PHA. Production of the polymer of bacterial isolates was found to be ranging from 21% - 57 % (w/w) of the biomass. The highest PHA yield was observed in Pseudomonas putida SD12, which was diagnosed according to diagnostic methods, i.e., colony morphology, gram staining, and then was confirmed by new gram-negative identification card (Vitek 2 NGNC). PHA accumulating was 2.80g/L, amounting to 57.20% (w/w) of cell dry weight. Waste frying oil was the best source of carbon which gave better results for PHA production than pure oil. PHA production was 2715 ppm with comparison of 1223 mg /3mlwhen used pure oil as a carbon source when incubated at 30°C after 48 hours.