L Tyrosine vs. Dextroamphetamine In a sleep deprivation study, L Tyrosine actually outperformed one of Adderall's active stimulants (dextroamphetamine) in key cognitive tests, like mathematical processing and logical reasoning, even after 30 hours with Figure 6 from The Oxidation of Tyrosine containing Peptides by Tyrosinase * Semantic Scholar Tyrosine Decarboxylase Worthington Enzyme Manual Worthington Biochemical Colorimetric and visual detection of tyrosine based on its copper catalyzed enzymatic oxidation to dopamine and subsequent reductive formation of colored gold nanoparticles using copper ions Microchimica Acta Springer Nature Link Sensing Tyrosinase Activity Encyclopedia MDPI