Taninos de diferentes especies vegetales en la prevención del fotoenvejecimiento

the use of some natural substances, specifically phenolic structures such as flavonoids and oligomeric catechines has proved to be a source of protection for the body. their antimicrobial, antioxidant and photoprotective properties are well-known and they are also recognized as protease inhibitors such as elastase. given their structural similarities, condensed tannins from various vegetal species, such as pine tree, casuarine, mimosa, pine cones, eucalyptus and soplillo were studied. in the last few years, special attention has been paid to the study of new substances with physical and chemical characteristics, capable of preventing disorders leading to skin mutations resulting from ultraviolet radiations mainly due to the increased environmental pollution and the depletion of the ozone layer. the objective of this paper was to determine the photoprotective capacity and the possible mechanism of action of tannins. to this end, 3 techniques were applied: photoprotection in bacteria (e. coli); spontaneous or induced antioxidant capacity in rat brain homogenate and antielastase activity. the results revealed that tannins from all vegetal species were able to protect bacteria against uv radiation, which coincides with a good antioxidant and antielastase activity. however, eucalyptus showed lower antioxidant and antielastase activity