Advances in green technologies for biocatalytic synthesis of chiral compounds: from enzymatic catalysis to...

Chiral compounds are highly valuable in pharmaceuticals and materials because of their distinct stereostructures. However, traditional synthesis methods often encounter difficulties, such as demanding reaction conditions and substantial pollution. Biosynthetic technologies, harnessing the intrinsic features of enzymatic catalysis-such as high stereoselectivity and environmental benignity-have established themselves as a pivotal strategy to surmount these traditional limitations. This article reviews recent advances in biocatalytic synthesis of chiral compounds. Key developments include enzyme engineering for precise chiral center formation-through modification of oxidoreductases and lyases, and design of bifunctional and artificial enzymes-as well as photo- and electro-enzymatic catalysis that merge energy-driven processes with biocatalysis for efficient synthesis under mild conditions. Microbial engineering using engineered Escherichia. coli and yeast enables scalable production of chiral compounds, including chiral sesquiterpenes (e.g., (-)-β-elemene, drimenol, albicanol), chiral alkaloid precursors (e.g., (-)-dehydrobrevianamide E), and other high-value chiral intermediates, via optimized metabolic pathways. Mechanistic studies on imine reductases and amino acid dehydrogenases support rational enzyme design. Current technologies exhibit green characteristics, yet confront challenges such as enzyme stability. Looking ahead, the integration of interdisciplinary technologies is expected to drive the intellectualization and sustainability of chiral synthesis technologies.