Photobiological characteristics of chlorophyll a derivatives as microbial PDT agents.
نویسندگان
چکیده
Chlorin-e6 (chl-e6) and a hydrogenated derivative (chl-e6H) were semi-synthesized, and their photophysical properties and photodynamic activity against Escherichia coli, Staphylococcus aureus and Candida albicans evaluated. Methyl pheophorbide-a (Mepheo-a) was obtained from S. maxima using methanolic extraction with acid catalysis (CH3OH–H2SO4). Chlorin-e6 was prepared from Mepheo-a by basic hydrolysis with H2O–acetone and NaOH. Hydrogenated Chlorin-e6 was synthesized by a similar procedure starting from the hydrogenated methyl pheophorbide-a (Mepheo-aH). Photophysical studies were performed in order to determine the singlet oxygen quantum yield of chl-e6H which is higher than that of chl-e6. The microorganism inactivation of chl-e6 and chl-e6H was investigated at two concentrations and three fluence levels. Both chl-e6 and chl-e6H showed microorganism inactivation against Gram-positive bacteria and a fungus.
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عنوان ژورنال:
- Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology
دوره 13 8 شماره
صفحات -
تاریخ انتشار 2014