Connelly, X. M. University of Puerto Rico, xanaconnelly@hotmail.com
Armstrong, R. M. University of Puerto Rico, neptune@caribe.net

 
EFFECTS OF ULTRAVIOLET RADIATION ON THE PHOTOPROTECTIVE PIGMENTS OF THE RED MANGROVE (RHIZOPHORA MANGLE)
 
Increased ultraviolet radiation in terrestrial and aquatic environments due to stratospheric ozone depletion has profound biological consequences. The purpose of this study was to investigate how UV radiation will affect bio-chemical and optical properties of the red mangrove (Rhizophora mangle). The halophytic red mangroves grew under ambient UV, 30 % ambient UV and excluded UV in a natural ecosystem in the southwest coast of Puerto Rico. The spectral quality and quantity of UV light reaching the mangrove trees under the experimental conditions were measured periodically with an Optronic Laboratories portable OL 754 UV-visible spectroradiometer. Healthy and mature mangrove leaves were collected in triplicate from each treatment. Pigments were extracted in methanol and analyzed spectrophotometrically and by HPLC. The photoprotective pigments showed statistically significant differences at 280nm (p=0.019) and at 330nm (p=0.003). The Lexan treatment (UV exclusion) showed the lowest absorbances (i.e. least amount of pigments). HPLC analyses have shown that there are at least seven pigments responsible for photoprotection in red mangrove. The most important pigments have been identified as flavonol glycosides.
 
Day: Tuesday, Feb. 2
Time: Poster
Location: Sweeney Center
 
Code: SS14TU1076S