Biodegradability studies of polyhydroxyalkanoate (PHA) film produced by a marine bacteria using Jatropha biodiesel byproduct as a substrate

Abstract

Polyhydroxyalkanoates are water-insoluble, hydrophobic polymers and can be degraded by microorganisms that produce extracellular PHA depolymerase. The present work was aimed to evaluate the degradability of Polyhydroxyalkanoate film produced by Halomonas hydrothermalis using Jatropha biodiesel byproduct as a substrate. PHB films were subjected to degradation in soil and compared with the synthetic polymer (acrylate) and blend prepared using the synthetic polymer (acrylate) and PHB. After 50 days, 60% of weight loss in PHB film and after 180 days 10% of blended film was degraded while no degradation was found in the synthetic film. Scanning electron microscopy and confocal microscopy revealed that after 50 days the PHB film and the blended film became more porous after degradation while synthetic film was not porous.The degradative process was biologically mediated which was evident by the control in which the PHB films were kept in sterile soil and the films showed inherent integrity over time. The TGA and DSC analysis shows that the melting temperatures were changed after degradation indicating physical changes in the polymer during degradation.

Implications of a novel Pseudomonas species on low density polyethylene biodegradation: an in vitro to in silico approach

“…However, the extent of biodegradation is identical to the biodegradation efficiency documented by cultures in previously conducted studies by Negi et al (Kapri et al 2010a ; Shrivastav et al 2011 ; Negi et al 2011 ; Girdhar et al 2013 ). Conducted studies on LDPE degradation in presence of bacterial consortium, where the biodegradation assay was followed by LDPE film characterization by SEM lead to capture of cracks and disruption on surface of degraded film in comparison to control (Kapri et al 2010a ; Shrivastav et al 2011 ; Negi et al 2011 ; Girdhar et al 2013 ). Micrographs demonstrates occurrence of several non-uniformlyscattered whitened areas and erosion zones illustrating surface erosion mechnism involved in degradation which might be due to enzyme catalytic action.…”

Factors affecting polyhydroxyalkanoates biodegradation in soil

“…The cost of bio-based plastics is still higher than that of the plastics produced from petroleum raw materials. The blending of PHAs with other bioplastics or with naturally decomposable materials, such as agricultural waste and natural fibers, is a strategy to reduce production cost or change the properties according to the goals established [32] . This process also changes the biodegradation properties and requires a new assessment of the blends biodegradability.…”

Process Parameters for Influencing Polyhydroxyalkanoate Producing Bacterial Factories: An Overview

“…Till date, these needs are being fulfilled by synthetic polymers (often called plastics), which are produced from petrochemicals [1] which makes them eco-'unfriendly'. The inherent nature of petroleum derived products, calls for a serving approach, in the form of Biopolymerspolymers derived from living organisms/renewable resources [2]. To satisfy the consumers and get acceptability substitute needs to exhibit similar (if not identical) characteristics to the product being replaced and so it is for biopolymers while replacing the synthetic polymers properties, ranging from molecular weight, density, melting point, crystallinity, glass transition temperature to O 2 -permeability, UVresistance, resistance to solvents, tensile strength and elongation to break [3].…”