Burned as waste for years, this overlooked plant material is poised to reshape how nylon gets made

June 14, 2026 report Burned as waste for years, this overlooked plant material is poised to reshape how nylon gets made Krystal Kasal Author Gaby Clark Scientific Editor Robert Egan Associate Editor Most people have seen nylon listed as a material on their clothing tags, but nylon is used in an array of other products, too, including automotive parts, wire insulation and medical supplies. Unfortunately, one of the building blocks of nylon, adipic acid, is produced from petroleum-derived benzene through energy-intensive processes and has a rather high carbon footprint. However, there may be a better way to produce this ubiquitous polymer. A new study, published in Nature, reports a novel method for converting lignin from plants into adipic acid with a higher yield than previous attempts. The method borrows processes from oil refineries but also uses engineered microbes to do some selective chemistry. A News & Views on the research is also published in Nature. The potential of lignin Lignin is an aromatic polymer that makes plants rigid. It is one of the most abundant organic polymers on Earth and possibly the largest untapped component of biomass. Millions of tons of lignin are left over as paper and biofuel byproducts every year, most of which is burned as low-value fuel. Lignin technically has the potential to be turned into highly useful industrial chemicals, but researchers have not figured out how to turn lignin into simple, high-value molecules, like aromatic compounds, efficiently enough for it to be done at scale. The byproduct containing lignin is often a messy mixture that is difficult to work with. The authors of the new study write, "Lignin has long been pursued as a source of aromatic compounds, but its heterogeneous composition and chemical reactivity limit its utility as a chemical feedstock. Lignin often degrades during extraction from biomass, and most methods for lignin depolymerization cleave only C–O bonds, resulting in the formation of complex mixtures of monomeric and oligomeric phenols." Because of this, existing lignin conversion methods typically top out at about 20 wt% yield to any single product, which is too low for competitive manufacturing. The products were often complex cocktails of phenolic compounds that are hard to separate and not ideal for further upgrading. But finding a high-yield route from lignin to adipic acid or similar nylon precursors could lead to a significant reduction not only in lignin biomass waste but also in the high carbon footprint of petrochemical plastics. Pairing oil refining processes with bacteria for lignin conversion The team involved in the new study has found a potential solution by combining a series of steps to make adipic acid from lignin. Their process combines some typical oil refinery-inspired strategies along with help from bacteria. Starting with poplar wood chips, the team used reductive catalytic fractionation (RCF) to extract and partially depolymerize lignin into an oil rich in phenolic monomers and oligomers. They then put the oil through a continuous hydrodeoxygenation reactor that stripped it of oxygen and phenolic groups that would impair oxidation. The next oxidation step cleaves carbon bonds in the resulting alkyl aromatics and then puts oxygen back in to create a mixture of water-soluble aromatic carboxylic acids. The team then used a unique process involving an engineered bacterium, called Pseudomonas putida, which converts most of the aromatic carboxylic acids in the mixture into a compound called muconolactone. Muconolactone could then be chemically converted to adipic acid. The experimental process resulted in a final adipic acid yield of around 26 wt% (gram adipic acid per gram lignin), but the team says the process could theoretically yield up to 57 wt% with some optimization. They also found that the approach works on lignin from multiple wood types, including poplar, pine and birch, indicating broad feedstock flexibility. Working toward higher yields A yield of 26 wt% is not quite enough for industrial manufacturing, but improvements in this process would get it closer to being a viable alternative for adipic acid production. Currently, there are some limitations involving the engineered microbe not yet being capable of metabolizing some minor components of the oxidation mixture. Another limitation is that reductive catalytic fractionation is not yet an economically mature technology and still requires relatively clean solvents and precious metal catalysts. However, the team is optimistic about future improvements to these limitations. They write, "Analogous processes have the potential to be applied towards condensed lignin substrates (for example, Kraft lignin), pending future development. With further metabolic engineering, the present bioconversion approach can be expanded and tuned to include increasingly complex autoxidation products (for example, benzene tricarboxylic acids) and target virtually any biologically accessible product." Written for you by our author Krystal Kasal, edited by Gaby Clark, and fact-checked and reviewed by Robert Egan—this article is the result of careful human work. We rely on readers like you to keep independent science journalism alive. If this reporting matters to you, please consider a donation (especially monthly). You'll get an ad-free account as a thank-you. Publication details Kathryn M. Mains et al, Lignin to adipic acid in a high-yield chemical and biological redox process, Nature (2026). DOI: 10.1038/s41586-026-10580-x Micaela Chacón et al, Hybrid refinery process turns plant material into industrially important chemical, Nature (2026). DOI: 10.1038/d41586-026-01586-6 Journal information: Nature © 2026 Science X Network