Fermentation

1. NAD⁺ Regeneration
   1. Fermentation
   2. lactic acid
      1. lactate dehydrogenase
   3. Ethanol
      1. step 1 = pyruvate decarboxylase
         1. thiamine pyrophosphate
      2. step 2 = alcohol dehydrogenase
         1. Zn ion
         2. liver
   4. Propionic acid
      1. org = Propionibacterium freudenreichii
   5. Butanol & acetone