Producing aromatic amino acid from corn husk by using polyols as intermediates

Vincent Fung; Yiying Xiao; Zhi Jun Daniel Tan; Xiaoqiang Ma; Jie Fu J Zhou; Smaranika Panda; Ning Yan; Kang Zhou

doi:10.1016/j.biomaterials.2022.121661

Producing aromatic amino acid from corn husk by using polyols as intermediates

Biomaterials. 2022 Aug:287:121661. doi: 10.1016/j.biomaterials.2022.121661. Epub 2022 Jul 1.

Authors

Vincent Fung¹, Yiying Xiao², Zhi Jun Daniel Tan¹, Xiaoqiang Ma¹, Jie Fu J Zhou¹, Smaranika Panda¹, Ning Yan³, Kang Zhou⁴

Affiliations

¹ Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, 117585, Singapore.
² Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, 117585, Singapore; Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou, 350207, China.
³ Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, 117585, Singapore. Electronic address: ning.yan@nus.edu.sg.
⁴ Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, 117585, Singapore. Electronic address: kang.zhou@nus.edu.sg.

PMID: 35842981
DOI: 10.1016/j.biomaterials.2022.121661

Abstract

Agricultural biomass remains as one of the commonly found waste on Earth. Although valorisation of these wastes has been studied in detail, the fermentation-based processes still need improvement due to the high cost of hydrolysing enzymes, and the presence of growth inhibitors which constrains the fermentation to produce high-value products. To address these challenges, we developed an integrated process in this study combining abiotic- and bio-catalysis to produce l-tyrosine from corn husk. The first step involved a one-pot hydrolytic hydrogenation tandem reaction without the use of the expensive enzymes, which yielded a mixture of polyols and sugars. Without any purification, these crude hydrolysates can be almost completely utilized by an engineered Escherichia coli strain, which did not exhibit any growth inhibition. The strain produced 0.44 g/L l-tyrosine from 10 g/L crude corn husk hydrolysates, demonstrating the feasibility of converting agricultural biomass into a valuable aromatic amino acid via an integrated process.

Keywords: Biomass valorisation; Food ingredient production; Hydrolytic hydrogenation; Metabolic engineering; Xylitol utilisation.