The stereoisomer D-phenylalanine (DPA) could be made by conventional natural and organic synthesis, either as only one enantiomer or like a component with the racemic combination. It doesn't be involved in protein biosynthesis even though it is present in proteins in small amounts - specifically aged proteins and food items https://ppaphclbuy93692.wikitron.com/1121148/5_simple_statements_about_phip_explained