Abstract
The photosensitizing properties of six anthraquinones (AQs): soranjidiol ( 1), soranjidiol-1-methyl ether ( 2), rubiadin ( 3), rubiadin-1-methyl ether ( 4), damnacanthal ( 5) and damnacanthol ( 6), isolated from leaves and stems of Heterophyllaea pustulata Hook. f. (Rubiaceae) were studied. By means of photobiological and photophysical methods in vitro, the type of photosensitization that these metabolites are capable of producing was determined. Whereas the photosensitized generation of superoxide anion radical ( O 2 - ) (Type I) was evaluated in leukocyte suspensions, singlet molecular oxygen ( 1O 2) production (Type II) was examined in organic solution. In addition, the quantum yield of 1O 2 ( Φ) in chloroform was measured for those AQs that generate it. It was established that 4 behaves exclusively as a Type I photosensitizer. By contrast, the others AQs act by both types of mechanisms, among which 5 showed the largest Φ of 1O 2.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
