Integrated Biotechnological Approaches Involving Plastic-Degrading Microbes, Microalgae-Derived Bioplastics, And Bioremediation for Plastic Pollution Control

Plastic pollution has become a dominant environmental issue in the 21st century as plastic production and consumption has increased exponentially throughout the world. Plastics have transformed many industries since their widescale adoption in the mid-20th century thanks to affordability, durability and light-weight. But these same properties have also enabled their environmental persistence, with extensive accumulation in terrestrial, aquatic and marine ecosystems. Millions of tons of plastic waste are estimated to pour into the environment every year; a fraction then breaks down into myriad microplastics and nanoplastics that pose serious ecological and human health risks.

Biotechnology has adapted itself to this need and is slowly but steadily proving to be a field that showcases new solutions through sustainable practices, especially when it comes to plastic pollution. Biotechnological approaches provide eco-friendly strategies for plastic degradation, recycling and replacement by utilizing the metabolic capacity of microorganisms, enzymatic reactions, and photosynthetic pathways. Microbial degradation, microalgae-based bioplastic production and bioremediation technologies stand out among these as they can establish a closed loop or integrated circular system for plastic waste management.

Microbial degradation of plastics involves the use of bacteria, fungi, and other microorganisms capable of breaking down complex polymer structures into simpler compounds. This process is primarily mediated by extracellular and intracellular enzymes such as hydrolases, esterases, and oxygenases, which cleave polymer chains through hydrolysis and oxidation reactions (Wei & Zimmermann, 2017). Over the years, several microbial species have been identified with the ability to degrade commonly used plastics such as polyethylene, polypropylene, and polyethylene terephthalate (PET). However, the efficiency of natural microbial degradation is often limited by factors such as polymer crystallinity, hydrophobicity, and environmental conditions (Restrepo-Flórez et al., 2014).