In enzymology, a mannitol 2-dehydrogenase (EC 1.1.1.67) is an enzyme that catalyzes the chemical reaction:D-mannitol + NAD+ D-fructose + NADH + H+. Thus, the two substrates of this enzyme are D-mannitol and NAD+, whereas its 3 products are D-fructose, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. This enzyme participates in fructose and mannose metabolism.http://www.creative-enzymes.com/product/Native-Leuconostoc-Mesenteroides-Mannitol-Dehydrogenase_1301.html