Natural Polyhydroxyalkanoates-An Overview of Bacterial Production Methods

Area of Science:

• Biotechnology
• Microbiology
• Polymer Science

Background:

• Polyhydroxyalkanoates (PHAs) are biodegradable biopolymers produced by microorganisms for carbon and energy storage.
• PHAs possess mechanical properties comparable to petrochemical plastics, presenting a sustainable alternative.
• High production costs, particularly with traditional carbon sources, hinder widespread PHA adoption.

Purpose of the Study:

• To provide a comprehensive overview of bacterial strains used for polyhydroxyalkanoate (PHA) production.
• To focus on strains exhibiting the highest PHA content in dry cell mass.
• To categorize strains based on their carbon source utilization strategies.

Main Methods:

• Literature review of bacterial strains for PHA production.
• Classification of strains based on carbon metabolism: autotrophy, methylotrophy, and heterotrophy.
• Analysis of PHA content in dry cell mass for selected strains.

Main Results:

• Identification of various bacterial strains capable of PHA synthesis.
• Highlighting strains with high PHA accumulation (e.g., certain Cupriavidus, Pseudomonas, and Bacillus species).
• Categorization of strains according to their ability to utilize CO2, CO, single-carbon compounds, or diverse organic substrates.

Conclusions:

• Diverse bacterial strains can produce PHAs, with significant variations in yield and composition.
• Autotrophic and methylotrophic strains offer promising avenues for cost-effective PHA production by utilizing inexpensive feedstocks.
• Optimizing bacterial strains and fermentation processes is crucial for advancing PHA as a sustainable plastic alternative.