Pollution and plastics have an intense correlation. Every year, millions of tons of nondegradable plastics are added to the environment. It can have a major negative impact on the environment, especially the greenhouse effect (Atiwesh et al. 2021). Plastic is the ideal material for a wide range of applications because of its low cost, stability, durability, and high mechanical and thermal properties. However, due to their inability to degrade, materials composed of plastic are widely used, which poses a concern on a global scale (Alabi et al. 2019). Recycling is the only method for dealing with plastic trash. Plastic is just 7% recycled. Another key solution is bioplastic. Bioplastics are currently being used more and more often all over the world. As an alternative to plastics created from petrochemicals, bioplastics are plastics that are naturally biodegradable (Thiruchelvi and Sikdar 2021). The marine biosphere is a significant source of biologically active and commercial-grade compounds with unique structural and metabolic properties. The biopolymers obtained from marine bacteria are studied for their crucial role in environmental cleanup (Baria et al. 2022). Although bacteria can endure extremes of temperature, salinity, pH, and pressure in a variety of environments, they extend their capacity for endurance by stimulating themselves with mechanisms and molecules that help them resist environmental stresses (Raval et al. 2013). Moreover, in applications involving bioplastics, scientists are focused on the synthesis of biodegradable and environmentally friendly materials. Polyhydroxy alkanoic acids, also known as polyhydroxyalkanoates (PHAs), are among these materials and are particularly intriguing due to their resemblance to petrochemical polyester and good formability (Kavitha et al. 2018). PHAs are green plastics that, when compared to conventional polymers in terms of synthesis and recycling, have a valuable social and environmental effect. Furthermore, when exploited in vivo, PHAs have no critical or long-term adverse effects on health. These bioplastics are an environmentally friendly, sustainable resource that can lessen the need for landfill space without being persistent or polluting (Raza et al. 2018). According to Anjum et al. (2016), PHAs are completely biodegradable, recyclable, non-toxic, biocompatible, and eco-friendly. PHAs can be composted by biological processes and are reported to break down within 49 days (Folino et al. 2020; Karan et al. 2019).
PHAs can be biodegraded in both soil and water environments. PHAs are applicable in both medical and industrial settings. PHAs are biopolyesters found in microorganisms, such as bacteria (Bacillus megaterium, Alcaligenes latus, Azotobacter beijerinckii, Ralstonia eutropha, Aeromonas hydrophila, Pseudomonas oleovorans and Cupriavidus necator), yeast (Arxula adeninivorans, Rhodotorula minuta) and blue-green algae (Gloeocapsa strain 6501, Chlorogloea fritschii) (Anjum et al. 2016; Tan et al. 2019). PHAs are made up of hydroxyalkanoate units, and there are two groupings based on how many carbon atoms are found in the monomer units: Poly-3-hydroxybutyrate-co-3-hydroxyvalerate copolymer [P(3HB-co-3HV)] is an example of a medium chain length PHA with 6–14 carbon atoms, and poly-3-hydroxybutyrate [P(3HB)] is an example of a short chain length PHA with 3–5 carbon atoms (Choi et al. 2021). The selection of the microorganism and the carbon source has a noticeable impact on the composition of PHA (Anjum et al. 2016). The best prospects to replace current plastics made of petrochemicals in the future are these biocompatible and biodegradable polymers.