In Silico Study of Enzymatic Degradation of Bioplastic by Microalgae: An Outlook on Microplastic Environmental Impact Assessment, Challenges, and Opportunities

Microplastics are tiny pieces of non-biodegradable plastic that can take thousands of years to break down. As microplastics degrade, they release harmful compounds into the environment, which can be found in the surroundings. The microplastics found in the environment are hard to detect and remove because of their small particle sizes. Microplastics cannot decompose naturally, so they accumulate in the environment and cause pollution. As a result, bioplastics can be produced from a vast array of substrates, including biopolymers, citrus peels, leather, and feather wastes. Blue-green microalgae namely Arthrospira platensis (spirulina) contains enzymes such as laccase and catalase which can be responsible for the degradation of bioplastics. In our study, we performed molecular docking to identify the binding affinities of different enzymes such as laccase and catalase with different substrates, focusing on determining the most suitable substrate for enhancing enzyme activity for degradation of bioplastics. The analysis revealed that veratryl alcohol is the most suitable substrate for laccase, whereas lignin is the more preferred substrate for catalase with the highest binding affinity score of - 5.9 and - 8.1 kcal/mol. Moreover, degradation, challenges, opportunities, and applications of bioplastics in numerous domains such as cosmetics, electronics, agriculture, medical, textiles, and food industries have also been highlighted.