NCIt definition : The racemic isomer of lactic acid, the biologically active isoform in humans. Lactic
acid or lactate is produced during fermentation from pyruvate by lactate dehydrogenase.
This reaction, in addition to producing lactic acid, also produces nicotinamide adenine
dinucleotide (NAD) that is then used in glycolysis to produce energy source adenosine
triphosphate (ATP).;