ID 1.3.1.5 DE Cucurbitacin Delta(23)-reductase. CA 23,24-dihydrocucurbitacin + NAD(P)(+) = cucurbitacin + NAD(P)H. CF Manganese. CC -!- Iron or zinc can replace manganese to some extent. CC -!- Cucurbitacin is a plant triterpenoid. //