Enriched extensin and cellulose for non-collapse biochar assembly to maximize carbon porosity and dye adsorption with high bioethanol production

Although extensin is a typical wall protein functional for plant cell wall construction and biomass production, its regulation on lignocellulose conversion into biofuels and bioproducts remains elusive. By collecting two extensin-overproduced rice straws (OsEXTLs), this study determined their cellulose levels significantly increased by 10 % along with soluble sugars and starch accumulation raised by 1–3.6 folds. After mild 0.5 % NaOH pretreatment, the OsEXTLs straws showed relatively enhanced biochemical conversion into total bioethanol production. Further under classic thermal-chemical conversion with the OsEXTLs enzyme-undigested lignocelluloses, this study generated the non-collapse biochar with more active chemical groups and the highest porosity, which caused mostly raised adsorption capacities with methylene blue (1162 mg/g) and Congo red (2714 mg/g) as a comparison with the previously-reported ones. Therefore, we proposed a mechanism model to illuminate how the extensin-enriched lignocellulose favors for higher-yield bioethanol conversion and better-performance biochar assembly, providing a novel strategy for desirable lignocellulose modification and effective biomass process.