β-nicotinamide adenine dinucleotide ( reduced form ) is mainly involved in the metabolism of substances and energy in cells, and produced in the citric acid cycle in glycolysis and cellular respiration, as a biohydrogen carrier and electron donor, it transfers energy and synthesizes ATP through oxidative phosphorylation on the inner mitochondrial membrane . So NADH is also known as mitochondria which exists in cell mitochondria of all animal and plant. NADH plays an important role in maintaining cell growth, differentiation, energy metabolism and cell protection.