Biotechnological advances in polyhydroxyalkanoates production from complex carbon sources

Abstract

Microbial synthesis of polyhydroxyalkanoate (PHA) at the industrialized level is already being exploited, although constrained, due to high costs. The biotransformation of complex constituents using microbial biocatalysts is gaining prominence in the production of hydroxyl fatty acid monomers. Recent research has focused on identifying and optimizing complex substrates that offer high carbon load, ready availability, and a suitable balance of nutrients for microbial growth and polymer bioaccumulation. Exploring this biosynthetic pathway can generate advanced and novel biopolymers, thereby expanding industrial applications. Different enzymes, both homo- and heterodimer in nature, are involved in PHA synthesis. Thus, the type of enzyme group the producing microorganism uses determines the carbon-length class of PHA generated. However, incubation time, growth nutrient supplements, and fermentation parameters such as temperature, pH, and oxygen content have constantly been hindrances to increasing the PHA yields from complex substrates. This review also situates the potency of using crude oil spills as carbon substrates for PHA production. This review further emphasizes the role of microbial biotransformation of hydrocarbonbased substrates, including crude oil spill, for the production of hydroxylated fatty acid monomers used in PHA synthesis, offering a novel prospects for bioremediation with value-added biopolymer generation.