Catalyzes the NADPH-dependent reduction of a wide variety of carbonyl-containing compounds to their corresponding alcohols. Displays enzymatic activity towards endogenous metabolites such as aromatic and aliphatic aldehydes, ketones, monosaccharides and bile acids, with a preference for negatively charged substrates, such as glucuronate and succinic semialdehyde (By similarity). Plays an important role in ascorbic acid biosynthesis by catalyzing the reduction of D-glucuronic acid and D-glucurono-gamma-lactone (By similarity). Functions as a detoxifiying enzyme by reducing a range of toxic aldehydes. Reduces methylglyoxal and 3-deoxyglucosone, which are present at elevated levels under hyperglycemic conditions and are cytotoxic. Involved also in the detoxification of lipid-derived aldehydes like acrolein (By similarity). Plays a role in the activation of procarcinogens, such as polycyclic aromatic hydrocarbon trans-dihydrodiols, and in the metabolism of various xenobiotics and drugs (By similarity). Displays no reductase activity towards retinoids (PubMed:12732097). a primary alcohol + NADP(+) = an aldehyde + H(+) + NADPH glycerol + NADP(+) = D-glyceraldehyde + H(+) + NADPH glycerol + NADP(+) = H(+) + L-glyceraldehyde + NADPH L-gulonate + NADP(+) = aldehydo-D-glucuronate + H(+) + NADPH L-gulono-1,4-lactone + NADP(+) = D-glucurono-3,6-lactone + H(+) + NADPH allyl alcohol + NADP(+) = acrolein + H(+) + NADPH hydroxyacetone + NADP(+) = H(+) + methylglyoxal + NADPH 3-deoxyfructose + NADP(+) = 3-deoxyglucosone + H(+) + NADPH (R)-mevalonate + NADP(+) = H(+) + mevaldate + NADPH NADP(+) + pyridine 3-methanol = H(+) + NADPH + pyridine-3-carbaldehyde kcat is 11000 min(-1) for pyridine-3-carbaldehyde as substrate. kcat is 2500 min(-1) for D,L-glyceraldehyde as substrate. Monomer. Belongs to the aldo/keto reductase family.