CIPYP   05508
CENTRO DE INVESTIGACIONES SOBRE PORFIRINAS Y PORFIRIAS
Unidad Ejecutora - UE
artículos
Título:
Photodynamic inactivation of Gram-positive bacteria employing natural resources.
Autor/es:
MAMONE, LEANDRO; DI VENOSA, GABRIELA; GANDARA, LAUTARO; SAENZ, DANIEL; VALLECORSA, PABLO; SCHICKINGER, SARA; ROSSETTI, MARIA VICTORIA; BATLLE, ALCIRA; BUZZOLA, F.; CASAS, ADRIANA
Revista:
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY
Editorial:
ELSEVIER SCIENCE SA
Referencias:
Lugar: Amsterdam; Año: 2014 vol. 133 p. 80 - 89
ISSN:
1011-1344
Resumen:
The aim of this paper was to investigate a collection of plant extracts
from Argentina as a source of new natural photosensitizers (PS) to be
used in Photodynamic Inactivation (PDI) of bacteria. A collection of
plants were screened for phototoxicity upon the Gram-positive species
Staphylococcus epidermidis. Three extracts turned out to be photoactive:
Solanum verbascifolium flower, Tecoma stans flower and Cissus
verticillata root. Upon exposure to a light dose of 55J/cm(2), they
induced 4, 2 and 3logs decrease in bacterial survival, respectively.
Photochemical characterisation of S. verbascifolium extract was carried
out. PDI reaction was dependent mainly on singlet oxygen and to a lesser
extent, on hydroxyl radicals, through type II and I reactions.
Photodegradation experiments revealed that the active principle of the
extract was not particularly photolabile. It is noticeable that S.
verbascifolium -PDI was more efficient under sunlight as compared to
artificial light (total eradication vs. 4 logs decrease upon 120min of
sunlight). The balance between oxidant and antioxidant compounds is
likely to be masking or unmasking potential PS of plant extracts, but
employing the crude extract, the level of photoactivity of S.
verbascifolium is similar to some artificial PS upon exposure to
sunlight, demonstrating that natural resources can be employed in PDI of
bacteria.