Cytochrome P450 monooxygenase; part of the gene cluster that mediates the biosynthesis of fusarielins F, G and H, decaketide compounds with 5 methylations and a decaline core that act as mycoestrogens as they stimulate growth of MCF-7 breast cancer cells (PubMed:22252016, PubMed:27983606). The initial compound in the pathway is produced by the reducing polyketide synthase FSL1. FSL1 lacks an active enoyl reductase (ER) domain and biosynthesis of fusarielins relies on the trans-acting enoyl reductase FSL5, before it is released through hydrolysis catalyzed by the thioesterase FSL2 (PubMed:22252016, PubMed:27983606). Fusarielins F, G, and H have a C11=C12 cis double bond and is fully reduced between C10 and C11 and between C12 and C13. FSL3 can be involved in the formation of the C11=C12 cis double bond by moving a hypothetical C10=C11 or C12=C13 trans double bond to form prefusarielin (PubMed:27983606). Prefusarielin is oxygenated at C15 and C16 by FSL4, resulting in fusarielin F, which subsequently is epoxidized into fusarielin G by the same enzyme (PubMed:27983606). The final step in the pathway is a reduction of the carboxylic acid moiety to yield fusarielin H via a still undetermined mechanism (PubMed:27983606). Secondary metabolite biosynthesis. Expression is positively regulated by the fusarielin biosynthesis cluster-specific transcription factor FSL7, probably via its binding at the 5'-CGGNNNCCG-3' motif present in the promoter of all the cluster genes. Abolishes the production of fusarielins F, G and H, but accumulates the intermediate prefusarielin. Belongs to the cytochrome P450 family.