Doris Ribitsch, Michael B. Schick, Michael Sander, Motonori Yamamoto, Georg M. Guebitz, Karolina Haernvall, Hassan Amer, Michael T. Zumstein, Kristopher McNeill, Sabine Zitzenbacher
Polyesters of 2,5-furandicarboxylic acid (FDCA) have gained attention as they can be regarded as the bio-based alternatives to the petroleum-based polyesters of terephthalic acid. However, only little is known about the biodegradation and enzymatic hydrolysis of FDCA-based polyesters. This work aims to investigate the influence of different polyols on enzymatic hydrolysis of FDCA-based polyesters. A series of polyesters containing various polyols are synthesized and analyzed regarding susceptibility to enzymatic hydrolysis by cutinase 1 from Thermobifida cellulosilytica (Thc_Cut1). FDCA-based polyesters’ number average molecular weight (Mn) ranged from 9360–35 800 g mol−1 according to gel permeation chromatography (GPC) analysis. Differential scanning calorimetry (DSC) analyses show decreasing glass transition temperature (Tg) with increasing diol chain length. Crystallinity of all polyesters is below 1% except for polyesters containing 1,6-hexanediol, 1,8-octanediol, and 1,12-dodecanediol for which calculated crystallinities are 27, 37, and 30%, respectively. Thc_Cut1 hydrolyzes all tested polyesters with preference for polyesters containing 1,5-pentanediol and 1,9-nonanediol (57.7 ± 7.5 and 52.8 ± 4.0% released FDCA). Enzyme activity increases when the linear diol 1,3-propanediol is replaced by the branched analog 1,2-propanediol or ethoxy units are introduced into the polyester chain. The results will contribute to expand the knowledge of microbial biodegradation of FDCA-based polyesters.
A series of bio-based 2,5-furandicarboxylic acid (FDCA)-based polyesters are synthesized with various polyols via direct esterification, followed by investigating their susceptibility to enzymatic hydrolysis by cutinase 1 from Thermobifida cellulosilytica (Thc_Cut1). The influence of various polyols on enzymatic hydrolysis by Thc_Cut1 is studied in terms of released amount of FDCA. The results help overcome previous knowledge gaps on the enzymatic hydrolysis of FDCA-based polyesters and is of larger interest given that FDCA-based polyester have recently received increasing attention both in the scientific and industrial communities.