Identification of pesticide-degrading Pseudomonas strains as poly-β-hydroxybutyrate producers

Abstract

Polyhydroxybutyrate (PHB) is an ecological promising substitute for polypropylene because it is biocompatible, biodegradable and can be produced by renewable sources. This study investigated PHB accumulation on pesticide-degrading Pseudomonas. 14 strains of pesticide-degrading Pseudomonas isolated from subtropical lowland soil in southern Brazil were analyzed using optical microscopy. Lipid inclusions were identified in four strains, and three of them, which degraded the pesticide carbofuran, had extensive granules accumulation which was detected by transmission electron microscopy. These strains were cultivated in a shaker at 28°C and the polymer was characterized by Fourier transform infrared (FTIR) spectroscopy. Strain CMM43 had the best accumulation after 48 h. The biopolymer was identified as poly-β-hydroxybutyrate.

Key words: Polyhydroxybutyrate (PHB), pesticide-degrading Pseudomonas sp., microscopy, subtropical lowland soil.