Xylene

2,2-diphenyl-1-picrylhydrazyl (DPPH), 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), ibuprofen, lidocaine hydrochloride, and caffeine were purchased from Sigma Aldrich (Poznań, Poland); disodium phosphate and potassium dihydrogen phosphate from Merck, Darmstadt (Germany); Biobase, beeswax were purchased from Mazidła.com (Poznań, Poland); grape seed oil was purchased from Monini (Spoleto, Italy); sodium acetate anhydrous, potassium persulfate, potassium acetate, xylene, 99.5% acetic acid, aluminium chloride, 36% hydrochloric acid, sodium chloride, potassium chloride, sodium sulphate anhydrous as well as propylene glycol, ethanol, and methanol were from Chempur (Piekary Śląskie, Poland), whereas acetonitrile for HPLC from J.T. Baker, (Landsmeer, The Netherlands). All reagents were of analytical grade.

Oxytetracycline dihydrate (CAS number: 6153–64-6) was purchased from Sigma-Aldrich. Methanol (HPLC grade) for elution was purchased from POCH. To perform HPLC, we used formic acid and acetonitrile purchased from VWR. To determine aromatisation efficiency, (1β-³H)-androstenedione was used, purchased from Perkin Elmer. Methylene chloride, NADPH, Tris–HCl buffer, active charcoal and scintillation liquid: Ultima Gold™ XR LSC Coctail were purchased from Sigma Aldrich. For histological evaluation, we used haematoxylin and eosin purchased from Sigma Aldrich and formaldehyde, xylene and paraffin wax which were purchased from Chempur.