Anthraquinone

Anthraquinone (AQ, 97%), octafluoroAnthraquinone
(AQ-F₈, 96%), 1,4-methoxyAnthraquinone (1,4-OMe-AQ, >99%),
1,4-difluoroAnthraquinone (1,4-F-AQ, 98%), ferrocene (Fc), and tetrabutylammonium
hexafluorophosphate (TBAPF₆) were purchased from Sigma-Aldrich.
1-ChloroAnthraquinone (1-Cl-AQ, 98%) was purchased from Thermo Fisher
Scientific. 2-ChloroAnthraquinone (2-Cl-AQ, >99%) was purchased
from
Chemcruz Enterprises Ltd. 1-HydroxyAnthraquinone (1-OH-AQ, >95%)
was
purchased from Cayman Chemical Company. Dimethyl sulfoxide (DMSO)
was purchased from Thermo Fisher Scientific. All chemicals were used
without further purification.

All the materials used were of high grade without further purification. 4-amino benzoic acid, 9-anthracenecarboxaldehyde and anthraquinone were purchased from Sigma Aldrich (St. Louis, MO, USA) and used as such. The solvent used was ethanol (analytical grade) used as such and purchased from Fisher Scientific, Bangalore, India.

Anthraquinone and six derivatives with different substituents on the aromatic ring were obtained from Sigma-Aldrich (St. Louis, MO, USA). Trichomonas vaginalis human strain G3 was from Patricia Johnson, University of California at Los Angeles, CA, USA, Tritrichomonas foetus feline strain D1 was from Lynette Corbeil at the University of California at San Diego, CA, USA, and feline Trichomonas foetus-like organism (strain C1) from Stanley Marks, University of California at Davis, School of Veterinary Medicine, CA, USA. The pathogenic and nonpathogenic bacteria and pathogenic fungi were obtained from the in-house United States of Agriculture (USDA) collection or from the American Type Culture Collection (ATCC, Manassas, VA, USA).

The electrolytes were prepared by dissolving the corresponding salts, lithium bis(trifluoromethanesulfonyl)imide (Solvay), and/or tetrabutylammonium hexafluorophosphate (Sigma-Aldrich) in water and/or DMSO (Sigma-Aldrich). Ferrocene and anthraquinone were purchased from Sigma-Aldrich.

Isopimpinellin (MicroSource Discovery Systems Inc., Gaylordsville, CT, USA) was used at 25 μM unless indicated otherwise. Xanthone was used at 25 μM unless stated otherwise, LY294002 at 50 μM, pyocyanin at 50 μM and disodium cromoglycate at 0.5 pg/μl (all obtained from Sigma-Aldrich, Poole, UK). Roscovitine was used at 20 μM (New England Biolabs, Hitchin, UK) and Z-VAD-FMK at 100 μM (Calbiochem, Manchester, UK). Nedocromil was used at 0.4 pg/μl and was a kind gift from Professor Rod Flower (William Harvey Research Institute, London, UK). The related benzopyrones anthraquinone, 4-chromanone, 1,2,3,4-tetrahydranaphthalene and xanthene were also obtained from Sigma-Aldrich, whereas anthrone and dihydrocoumarin were acquired from Alfa Aesar (Heysham, UK) and α-tetralone from L. Light & Co. Ltd (Colnbrook, UK). GM-CSF (from PeproTech, London, UK) was used at 0.01 μg/ml. Zebrafish were treated with compounds by immersion, with the exceptions of disodium cromoglycate and nedocromil, which were administered by vascular injection into the Duct of Cuvier, alongside fluorescein as a marker for successful injection. DMSO (Sigma-Aldrich) or water were used as vehicle controls, as indicated.