Directed evolution of enzymes for sustainable biocatalysis in the green synthesis of cardiac drugs.

Enzyme-directed evolution provides an environment-friendly method to optimize biocatalysis during the preparation of cardiac drugs. The study showed enzyme functionality and selectivity characteristics, such as cytochrome P450 monooxygenases and ketoreductases, transaminases, and hydrolases. The screening process revealed various variants of an enzyme that showed 7-fold elevated k_cat catalytic turnover capabilities, and k_cat/K_m proficiency was boosted to 12-fold. CYP450 (cytochrome P450) -F87A showed 97 % substrate conversion, and the enzyme KRED-M181T reached 99 % enantioselectivity. Enzymes showed significantly better resistance to varied melting temperatures (T_m + 10-15 °C) while maintaining 85 % activity levels in 30 % ethanol solutions. Synthesizing compounds via biocatalysis generated less waste than conventional methods because its E-factor reached 3.7 while conventional synthesis had 15.2, and CO₂ emissions decreased by 50 % between the two methods. Enzymatic synthesis shows positive results from green chemistry evaluations because it decreases energy usage by 45 % while maintaining an 85-92 % atom economy. Laboratory research proves the future potential of directed evolution for cardiac drug synthesis processes by increasing efficiency and sustainability. Although this study was conducted at laboratory scale, these findings together on continuous-flow biocatalysis support the feasibility of future industrial application. Overall, this work highlights the potential of directed evolution to develop selective, stable, and sustainable biocatalysts for greener pharmaceutical manufacturing.