• Lactic acid fermentation involves homo- and heterofermentative pathways, with key enzymes such as lactate dehydrogenase and pyruvate decarboxylase regulating carbon flux.
• Process parameters including pH, temperature, and substrate concentration significantly influence lactic acid yield and productivity, with fed-batch and continuous modes offering advantages.
• Metabolic engineering of lactic acid bacteria, including overexpression of key genes and knockout of competing pathways, has enhanced lactic acid production by up to 30%.
• Lactic acid and its polymers are crucial in pharmaceutical applications, including biodegradable drug delivery systems and tissue engineering scaffolds.