In enzymology, an acyl-CoA dehydrogenase is an enzyme that catalyzes the chemical reaction acyl-CoA + NADP+ ⇌ \rightleftharpoons 2,3-dehydroacyl-CoA + NADPH + H+Thus, the two substrates of this enzyme are acyl-CoA and NADP+, whereas its 3 products are 2,3-dehydroacyl-CoA, NADPH, and H+. Wikipedia