Oxoid campygen

Bacteria were grown microaerobically (Oxoid Campygen; Thermo Fisher Scientific, Waltham, MA, USA) at 42°C and routinely resuscitated from frozen stocks by first growing them overnight on blood agar (Columbia agar plates supplemented with 5% horse blood; Oxoid, Basingstoke, UK), followed by overnight incubation in brucella broth (Becton, Dickinson and Company, Franklin Lakes, NJ, USA). To collect bacteria and/or broth, cultures were centrifuged at 8,000 × g for 5 to 10 min. Where indicated, the bacteria were heat inactivated at 70°C for 10 min, and complete inactivation was verified by plating on blood agar.

Dichloromethane (DMC), methanol (MeOH), sodium sulfate anhydrous, DPPH (2,2-diphenyl-1-picrylhydryl), ABTS (2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid), acetylcholinesterase (AChE), acetylthiocholine (ATC), phosphate buffered saline, Ellman’s reagent (donepezil, 5,5′-dithiobis(2-nitrobenzoic acid)), tris hydrochloride (Tris-HCl), magnesium chloride hexahydrate and 2,3,5-Triphenyl tetrazolium chloride (TTZ) were purchased from Sigma-Aldrich (San Luis, MO, USA). The microbiological media such as Mueller Himton broth, Mueller Hinton II broth and fluid thioglycollate medium were purchased from DIPCO (Quito, Ecuador). Horse serum and Oxoid CampyGen were purchased from Thermo Fisher Scientific (Waltham, MA, USA). The standard aliphatic hydrocarbons were purchased from ChemService (West Chester, PA, USA). Helium was purchased from INDURA (Quito, Ecuador). All chemicals were of analytical grade and used without further purifications.

Bacterial strains used in this study were C. jejuni 11168-O (courtesy of Prof. D. G. Newell, Guildford, UK), C. jejuni 81-176 (courtesy of Prof. Christine Szymanski, University of Alberta, Edmonton, AB, Canada), and C. coli NCTC 11366 (Griffith University culture collection, Gold Coast, Australia). Cells were grown at 42 °C microaerobically (85% N₂, 10% CO₂ and 5% O₂) on Mueller-Hinton agar (MHA) and in Mueller-Hinton broth (MHB), supplemented with Trimethoprim (5 µg mL⁻¹) and Vancomycin (10 µg mL⁻¹) (TV) (Sigma-Aldrich, Saint Louis, MO, USA). Microaerobic conditions were established by using Oxoid CampyGen (Thermo Scientific, Scoresby, Australia).