*4.1. Samples*

Highly purified (>95% by SDS-PAGE) recombinant human CYP51A1 protein was expressed and purified as previously described [38]. Low molecular weight compounds: lanosterol (PubChem CID 246983, CAS Number 79-63-0), natural substrate of CYP51A1, and ketoconazole (PubChem CID 456201, CAS Number 65277-42-1), azole inhibitor of CYP51A1, were obtained from Cayman Chemicals (Ann Arbor, MI, USA), baicalein (Pub-Chem CID 5281605, CAS Number 491-67-8) was obtained from Sigma Aldrich (St. Louis, MO, USA), luteolin (PubChem CID 5280445, CAS Number 491-70-3) and luteolin 7,3- disulfate (PubChem CID 44258153) were purified in the G.B. Elyakov Pacific Institute of Bioorganic Chemistry (Vladivostok, Russia) by water–alcohol extraction, followed by chromatographic purification from the sea plants of *Zosteraceae* genus [55,56].
