Concentration-dependent dual prooxidant/antioxidant activity of a prenyl flavonoid

CABRERA JOSE L.; PERALTA MARIANA A; PARAJE, MARÍA G; ORTEGA, MARÍA G.

Bansko

Congreso; ural Products Utilization: from Plants tInternational Conference on Nato Pharmacy Shelf; 2017

Prooxidant-antioxidanteffect 8PP, a prenylflavonoid from Daleaelegans on Candida albicans biofilmswas investigated. We previouslyreported that sensitive C. albicans(SCa) and resistant C. albicans (RCa)biofilms were strongly inhibited in a dose-depending manner (50 µM-100 µM),with accumulation of endogenous oxidative metabolites that increased antioxidant defenses.  The antifungal activity of 8PP (200-1000 µM), thecellular stress imbalance and the architecture of biofilms were studied. Biofilms was studied bycrystal violet and confocal scanning laser microscopy (CSLM) with COMSTATanalysis. Superoxide anion radical (O2·-) were assessed byreduction of Nitro blue tetrazolium, intracellular ROS was detected by aDCFH-DA and visualized by CSLM; reactive nitrogen intermediates by Griess. Theactivities of the superoxide dismutase and the total antioxidant capacity weredeterminate.An antioxidant effect was detected at1000 µM and levels ofoxidant metabolites remain low, by mainly action of non-enzymatic system, withmajor changes in the SCa. COMSTATanalysis showed that biofilms treatedwith higher concentrations exhibited differentdiffusion distances with altered topographic surface architectures, voids,channels and pores that could change the flow inside the matrix of biofilms. Wedemonstrate for first time, a concentration-dependent dual prooxidant-antioxidant action of 8PP, which canalter antifungal activity on biofilms.