FAD-linked oxidoreductase; part of the gene cluster that mediates the biosynthesis of sorbicillinoids, a diverse group of yellow secondary metabolites that restrict growth of competing pathogenic fungi but not of bacteria (PubMed:25580210, PubMed:28618182). Sorbicillinoids biosynthesis requires the action of two PKSs (PubMed:25580210). SorA iteratively combines three acetyl units and the growing chain is modified by the ketoacyl reductase subunit, and optional by the enoyl reductase subunit in the second cycle (PubMed:25580210). The polyketide is then handed over to the PKS SorB, which adds three more acetyl units, and two methyl groups (PubMed:25580210). SorB releases an aldehyde, which undergoes spontaneous cyclization resulting in the formation of sorbicillin or 2',3'-dihydrosorbicillin (PubMed:25580210). The monooxygenase sorC oxidizes sorbicillin and 2',3'-dihydrosorbicillin to 2',3'-dihydrosorbicillinol and sorbicillinol, respectively (PubMed:28618182). The oxidoreductase sorD further converts sorbicillinol into oxosorbicillinol (PubMed:28618182). Sorbicillinol is the building block for the other sorbicillinoids such as disorbicillinol, bisvertinolon, and dihydrobisvertinolone (By similarity). Secondary metabolite biosynthesis. Leads to the accumulation of sorbicillinol and impairs the production of oxosorbicillinol (PubMed:28618182). Belongs to the oxygen-dependent FAD-linked oxidoreductase family.