What is the recyling of NAD unde anaerobic conditions?

Under anaerobic conditions, the recycling of NAD⁺ occurs primarily through fermentation processes. In lactic acid fermentation, for example, pyruvate accepts electrons from NADH, regenerating NAD⁺ and producing lactic acid. In alcoholic fermentation, pyruvate is converted to ethanol and carbon dioxide, also facilitating the oxidation of NADH back to NAD⁺. This recycling is crucial for sustaining glycolysis, allowing ATP production in the absence of oxygen.