2004 Folwell Avenue St. Paul, MN55108 United States
Ph.D. - Bio-organic Chemistry, University of Washington
Areas of Interest
Lignin-based Plastics, Lignin Biodegradation and Biosynthesis
The Lignin Chemistry Group, led by Prof. Simo Sarkanen, has challenged a prominent idea, dating from 1960, about lignin structure that has prevented the value of lignins as abundant renewable materials from being fulfilled. As a result, the Lignin Chemistry Group is the first to have created plastics with >90% levels of industrial kraft lignin that surpass polystyrene in mechanical behavior. These revealing formulations for plastics can be adapted to lignins from emerging biorefinery operations. A major effort has been initiated to convert underutilized lignins into biodegradable plastics for making a wide range of consumer items like computer consoles, automobile dashboards, speaker enclosures, garden furniture, etc.
The peroxidases and laccases identified in the nineteen-eighties as being responsible for the first step in lignin biodegradation suffer from a serious problem: these enzymes can also (re)polymerize lignin components. Members of the Lignin Chemistry Group identified particular flavin-dependent monooxygenases as versatile enzymes that can cleave lignin macromolecules without bringing about their (re)polymerization. The importance of this discovery was affirmed by the award of U.S. Patent No. 9,796,993 in October 2017.
The overwhelming majority of lignin researchers believe that lignin macromolecules do not possess explicit (non-random) primary structures. However, members of the Lignin Chemistry Group have shown that, without covalent participation, pre-existing lignin macromolecules influence the molecular weight distributions of lignin components that are formed from monolignols in vitro. Analogous effects in muro would have profound effects on native macromolecular lignin configuration.
ESPM 3000 Chemicals and Plastics from Plants and Trees
Preparation of a current Lignin Chemistry and Biochemistry text
Thermoplastics with very high (>90%) lignin contents.
Functional lignin degrading enzymes.
Template polymerization in lignin biosynthesis.
• Chen, Y.-r., Sarkanen, S. Biodegradable lignin-based plastics. In (M. Dusselier, J.-P. Lange, eds.) Biodegradable Polymers in the Circular Plastics Economy; Wiley-VCH Verlag, Weinheim, Germany, 2021 (36 pages).
• Chen, Y.-r., Sarkanen, S., Wang, Y.-Y. Lignin-only polymeric materials based on unmethylated unfractionated kraft and ball-milled lignins surpass polyethylene and polystyrene in tensile strength. Molecules 2019, 24, 4611 (15 pages).
• Wang, Y.-Y., Chen, Y.-r., Sarkanen, S. Blend configuration in functional polymeric materials with a high lignin content. Faraday Discuss. 2017, 202, 43-59.
• Sarkanen, S., Chen, Y.-r., Wang, Y.-Y. Journey to polymeric materials composed exclusively of simple lignin derivatives. ACS Sustainable Chem. Eng. 2016, 4, 5223-5229. • Wang, Y.-Y., Chen, Y.-r., Sarkanen, S. Path to plastics composed of ligninsulphonates (lignosulfonates). Green Chemistry 2015, 17, 5069-5078.
• Chen, Y.-r., Sarkanen, S., Wang, Y.-Y. Lignin-Degrading Enzyme Activities. In (M.E. Himmel, ed.) Methods in Molecular Biology: Biomass Conversion; Humana Press, New York, NY, 2012, pp. 251-268.
• Chen, Y.-r., Sarkanen, S. Macromolecular replication during lignin biosynthesis. Phytochemistry 2010, 71, 453-462.
• Nutsubidze, N.N., Sarkanen, S., Schmidt, E.L., Shashikanth, S. Consecutive polymerization and depolymerization of kraft lignin by Trametes cingulata. Phytochemistry 1998, 49, 1203-1212.
• Guan, S.-y., Mlynár, J., Sarkanen, S. Dehydrogenative polymerization of coniferyl alcohol on macromolecular lignin templates. Phytochemistry 1997, 45, 911-918.
Compositions Including Lignin and Methods for Making the Same: Chen, Y.-r.; Sarkanen, S. 2020. U.S. National Stage Patent Application Number 16/982,818, filed on September 21.
Compositions Including Lignin: Chen, Y.-r.; Sarkanen, S.; Wang, Y.-Y. U.S. Patent 2018, No. 10,119,027 issued June 25.
Lignin Degrading Methods and Compositions: Chen, Y.-r.; Sarkanen, S.; Wang, Y.-Y. U.S. Patent 2017, No. 9,796,993 issued October 24.
Compositions Including Lignin: Chen, Y.-r.; Sarkanen, S.; Wang, Y.-Y. 2015, International Patent Application No. PCT/US2015/020599, filed March 13.
Lignin Degrading Methods: Chen, Y.-r.; Sarkanen, S.; Wang, Y.-Y. International Patent Application No. PCT/US12/69243 filed December 12, 2012. National Stage Application for U.S. (No. 14/364,448) filed June 11, 2014; corresponding National Stage Application for Canada filed June 18, 2014.
Compositions Based on Lignin Derivatives: Sarkanen, S.; Li, Y. U.S. Patent 2001, No. 6,172,204 issued January 9 (licensed to cycleWood Solutions, LLC, September 27, 2011).