Exploring potooxidative degradation pathways of harmol and harmalol alkaloids in water: effects of pH, excitation sources and atmospheric conditions

FERNANDO DIEGO VILLARRUEL; MARIA PAULA DENOFRIO; TOBIAS SCHMIDT DE LEON; ROSA ERRA-BALSELLS; EZEQUIEL WOLCAN; FERNANDO SEBASTIAN GARCÍA EINSCHLAG; FRANCO M. CABRERIZO

PHYSICAL CHEMISTRY CHEMICAL PHYSICS

ROYAL SOC CHEMISTRY

Año: 2024 vol. 26 p. 6068 - 6079

1463-9076

This work explores the photochemical degradation of the cationic species of 7-hydroxy-1-methyl-2H-pyrido [3,4-b]indole or harmol (1C) and the corresponding partially hydrogenated derivative 7-hydroxy-1-methyl-3,4-dihydro-2H-pyrido [3,4-b]indole or harmalol (2C) in aqueous solution. UV–visible absorption and fluorescence emission spectroscopy coupled with multivariate data analysis (MCR-ALS and PARAFAC), HPLC and HRESI-MS techniques were used for both quantitative and qualitative analysis. The formation of hydrogen peroxide reactive oxygen species (ROS) was quantified, and the influence of pH, oxygen partial pressure and photoexcitation source on the photochemical degradation of both compounds was assessed. The potential implications on the βCs biosynthesis and their biological role in living systems is discussed.