Researchers at the Korea Advanced Institute of Science and Technology in Daegu have developed a novel method for producing heat-resistant bioplastic through microbial biosynthesis. This advancement was reported in a peer-reviewed article published in Trends in Biotechnology. The study highlights a strategic shift toward plastics created entirely from aromatic monomers, expanding the potential range of materials used in packaging, consumer goods, and industrial contexts.
Most conventional plastics used in packaging and manufacturing rely on ring-shaped aromatic structures, including materials like PET and polystyrene. The new work builds on previous efforts where microbes were guided to assemble polymers from alternating aromatic and non-ring (aliphatic) monomers. In contrast, the current study demonstrates the creation of polymers comprised exclusively of monomers bearing aromatic side chains, aiming to enhance thermal stability and structural performance under demanding conditions.
To reach this goal, the team designed a bespoke metabolic pathway that enables bacteria to synthesize an aromatic monomer known as phenyllactate. This intermediate is produced by recombining enzymes derived from multiple microbial sources. By integrating this pathway with a computer-guided design of a polymerase enzyme, the researchers achieved efficient assembly of phenyllactate units into a coherent polymer chain, enabling the formation of poly(D-phenylactate) with favorable properties for high-temperature or high-stress applications.
Through iterative optimization of both the microbial metabolism and the polymerase, the team demonstrated scalable production in fermentation setups, running at a 6.6-liter (1.7-gallon) scale. The engineered strain reached a polymer titer of 12.3 g per liter, representing a meaningful step toward viable manufacturing. For commercialization, the researchers aim to push yields toward 100 g per liter, a target that would improve process economics and enable broader use across markets.
Looking ahead, the researchers expect to diversify the palette of aromatic monomers and tailor the resulting polymers to suit a wider array of chemical and physical requirements. Future polymers may feature higher molecular weights and modified mechanical properties, catering to industrial contexts that demand durable, heat-stable materials with predictable performance profiles.
In related work, scientists are exploring repurposed byproducts from kimchi production as feedstocks for bioplastic creation. This approach exemplifies a growing emphasis on sustainable resource use, transforming traditional waste streams into value-added materials while reducing the environmental footprint of plastic manufacture. These efforts illustrate a broader trend toward bio-based plastics that combine performance with responsible manufacturing practices, aligning with goals for greener materials across multiple sectors. (citation: Trends in Biotechnology, 2024)