Biocatalytic enzyme and fungal systems for degrading and upcycling synthetic polymers and petroleum hydrocarbons

Background

String: Synthetic polymers such as polyethylene (PE), polypropylene (PP), and polyvinyl chloride (PVC) are among the most widely used materials in modern society, forming the backbone of packaging, construction, and countless consumer products. Their durability and resistance to degradation, while advantageous for product longevity, have led to a mounting global crisis of plastic pollution and persistent petroleum-based contaminants in the environment. Traditional recycling and remediation strategies—such as mechanical reprocessing, incineration, and chemical treatments—are often energy-intensive, costly, and environmentally damaging, resulting in significant carbon emissions and incomplete breakdown of polymeric materials. As a result, there is a pressing need for sustainable, efficient, and scalable solutions that can address the environmental burden posed by recalcitrant plastics and hydrocarbons.

Current biological approaches, including microbial and enzymatic degradation, have shown promise as greener alternatives but face significant limitations when applied to highly inert polymers like PE and PP. Most naturally occurring enzymes lack the necessary activity or specificity to cleave the strong C-H bonds in these materials, leading to slow reaction rates and incomplete degradation. Additionally, the hydrophobic and crystalline nature of many synthetic polymers hinders enzyme accessibility, further reducing the efficiency of biocatalytic processes. Attempts to enhance degradation through pretreatment or the use of aggressive chemical oxidants often negate the environmental benefits of biological methods. Thus, despite ongoing research, existing strategies remain inadequate for large-scale remediation and upcycling of synthetic polymers, underscoring the need for more effective biotechnological solutions.

Technology

This technology centers on the use of a specialized unspecific peroxygenase enzyme, MroUPO-TN, derived from the fungus Marasmius rotula, to break down stubborn synthetic polymers such as polyethylene, polypropylene, and polyvinyl chloride. The enzyme features a heme-thiolate active site and an aliphatic substrate channel that enables efficient C-H bond oxygenation and oxidative cleavage of polymers under mild, room-temperature conditions. Degradation can be achieved either by applying the isolated, glycosylated enzyme with hydrogen peroxide and organic co-solvents—which help swell the plastic for better enzyme access—or by cultivating whole fungal cells that secrete oxidative proteins and generate hydrogen peroxide in situ. Both approaches result in the formation of oxidized products like ketones and alcohols, a reduction in polymer molecular weight, and increased solubility of plastic fragments. The platform also includes engineered enzyme variants and combinatorial mixtures with other biocatalysts to further enhance degradation and upcycling of plastics and petroleum hydrocarbons.

What differentiates this technology is its combination of high selectivity, operational mildness, and versatility in addressing recalcitrant plastic waste. Unlike traditional recycling methods that require high energy input and harsh conditions, this solution operates at ambient temperatures and neutral pH, minimizing environmental impact and energy consumption. The MroUPO-TN enzyme exhibits remarkable stability—even in organic co-solvent mixtures—and can be tailored through protein engineering for improved activity and selectivity. Its ability to function both as an isolated enzyme and within living fungal cultures provides flexibility for various industrial and environmental applications, from soil and water remediation to plastic upcycling. The use of advanced analytical and mechanistic insights ensures robust monitoring and optimization, positioning this technology as a scalable, sustainable, and highly effective alternative for plastic degradation and valorization.

Benefits

• Efficient oxidative degradation of recalcitrant synthetic polymers (PE, PP, PVC) under mild, room-temperature conditions
• Environmentally friendly alternative to energy-intensive and harsh chemical recycling methods
• Versatile application using both isolated enzymes and whole-cell fungal cultures for in situ polymer breakdown
• Production of oxidized polymer fragments (ketones, alcohols) that are more soluble and suitable for upcycling
• High enzyme stability and activity in aqueous and organic co-solvent mixtures, enabling enhanced polymer accessibility
• Potential for protein engineering and enzyme combinations to optimize degradation efficiency and selectivity
• Scalable and sustainable platform for plastic waste remediation and valorization of petroleum hydrocarbons

Applications

• Plastic waste bioremediation
• Enzymatic plastic recycling
• Petroleum spill cleanup
• Upcycling plastics to value-added chemicals

Additional info

This biocatalytic platform utilizes MroUPO-TN, a heme-thiolate unspecific peroxygenase from *Marasmius rotula*, to oxidatively degrade synthetic polymers and hydrocarbons. The enzyme’s aliphatic substrate channel facilitates C-H bond oxygenation and oxidative cleavage under mild, room-temperature conditions. By employing engineered variants or whole-cell fungal cultures, the process reduces molecular weight and increases solubility, converting recalcitrant materials into oxidized fragments like ketones and alcohols for sustainable upcycling.