The function of ALDH3B1 (aldehyde dehydrogenase 3 family member B1, ENSG00000006534) is as follows. Oxidizes medium and long chain saturated and unsaturated fatty aldehydes generated in the plasma membrane into non-toxic fatty acids (PubMed:17382292, PubMed:23721920). May have a protective role against the cytotoxicity induced by lipid peroxidation (PubMed:17382292). Short-chain fatty aldehydes are not good substrates (PubMed:17382292). Can use both NADP(+) and NAD(+) as electron acceptor in vitro, however in vivo preference will depend on their tissue levels (PubMed:17382292). Low activity towards acetaldehyde and 3,4- dihydroxyphenylacetaldehyde (PubMed:17382292, PubMed:23721920). Able to metabolize aromatic aldehydes such as benzaldehyde to their acid form (PubMed:17382292). {ECO:0000269|PubMed:17382292, ECO:0000269|PubMed:23721920}.