A photo/biocatalytic system for visible-light driven <sc>l</sc>-alanine production from ammonia and pyruvate

The chemical structure of l-alanine is similar to that of l-lactic acid and its polymerisation product, poly(l-alanine) (poly-l-Ala), is a biodegradable nylon. There is a need for a method capable of synthesizing l-alanine, a monomer of poly-l-Ala, from a biobased material with a renewable energy source. In this work, visible-light driven l-alanine from biobased material pyruvate and ammonium ions with a system consisting of triethanolamine, water-soluble zinc porphyrin, pentamethylcyclopentadienyl coordinated rhodium complex, NAD+ and l-alanine dehydrogenase from Bacillus subtilis is established. In particular, the conversion yield for pyruvate to l-alanine was improved up to 100% in this system after 24 h irradiation.