Please use this identifier to cite or link to this item:

Influence Of Ultraviolet Radiation On The Pigmentation And Growth Of The Red Alga, Gracilaria Salicornia

File Description SizeFormat 
uhm_ms_3990_r.pdfVersion for non-UH users. Copying/Printing is not permitted2.35 MBAdobe PDFView/Open
uhm_ms_3990_uh.pdfVersion for UH users2.35 MBAdobe PDFView/Open

Item Summary

Title: Influence Of Ultraviolet Radiation On The Pigmentation And Growth Of The Red Alga, Gracilaria Salicornia
Authors: Kelly, Kevin E.
Issue Date: Aug 2005
Abstract: Physiological damage to macroalgae from both UVA (320-400 nm) and UVB (280-320 nm) radiation is well documented in the scientific literature. Due to the occurrence of mycosporine-like amino acids (MAAs) in marine algae from the poles to the tropics, and their UV absorption maxima between 310 and 360 nm, it is assumed that MAAs act as sunscreens to counter this stress while allowing the light-harvesting pigments to absorb the maximum photosynthetically active radiation (PAR, 400-700 nm) for growth. This study agrees with previous investigations that MAA concentration is positively correlated with natural doses of UV radiation. In addition, this study addresses the metabolic cost of producing these photoprotective compounds. Specifically, does this metabolic cost impact growth rate? Gracilaria salicornia was grown in both UV transparent (full sunlight) and UV filtered (50% reduced irradiance below 350 nm) 40-liter tanks, and growth rate and intracellular concentrations of photosynthetic pigments were compared during two time-series experiments (14 and 21 days) between June and August, 2003. Of the five MAAs consistently detected, porphra-334 (λmax=334) showed the quickest and most substantial divergence in concentration between the two treatments (full sunlight = higher concentration). Shinorine (λmax=334) and palythene (λmax=320) responses generally lagged by two to three days and were less pronounced. The concentration of palythene (λmax=360) and mycosporine-glycine (λmax=309) also diverged, but differences were very small for most days in each time-series. Pigment responses also diverged midway through the experiment, with carotenoid concentration in the control treatment increasing relative to the experimental treatment. Growth rates between the two treatments were not statistically different.
Rights: All UHM dissertations and theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner.
Appears in Collections:M.S. - Oceanography

Items in ScholarSpace are protected by copyright, with all rights reserved, unless otherwise indicated.