ABSTRACT
Historically, edible marine macroalgae or seaweeds (sometimes referred to as sea vegetables) from the Protista taxonomies Phaeophyceae (brown (B)), Chlorophyceae (green (G)), and Rhodophyceae (red (R)) have been commonplace in Paci’c (e.g., Indonesia, Philippines, New Zealand, Hawaii) and Asian (e.g., Japan, China, Korea) diets, and albeit to a lesser extent, in those of France, Iceland, Ireland, Norway, Wales, as well as the Atlantic Canadian provinces and Maine in the United States. A more recent, growing area of inquiry has focused on marine macroalgae and constituents as functional foods and nutraceuticals for potential bene’cial health effects as sources of antioxidants and bioactives in reducing the risk for various diet-related chronic diseases such as atherosclerosis
12.1 Introduction .......................................................................................................................... 143 12.2 Background and Occurrence of Mycosporine-Like Amino Acids (MAAs) ........................ 146 12.3 MAA Solubility and Extraction Methods ............................................................................ 148 12.4 MAA Identi’cation and Quantitation ................................................................................... 150
12.4.1 Ultraviolet-Visible Spectrometry (UV/Vis) .............................................................. 150 12.4.2 Fourier Transform Infrared Spectroscopy (FTIR) ................................................... 150 12.4.3 High-Performance Liquid Chromatography (HPLC) .............................................. 151 12.4.4 Liquid Chromatography-Mass Spectroscopy (LC/MS) ........................................... 152 12.4.5 Nuclear Magnetic Resonance (NMR) Spectroscopy of MAAs ............................... 152 12.4.6 Gas Chromatography and Mass Spectroscopy (GC/MS) of MAAs ........................ 153
12.5 Antioxidant Activities of MAAs .......................................................................................... 153 12.6 Stability of MAAs ................................................................................................................ 159
12.6.1 Thermal Stability of MAAs ..................................................................................... 159 12.6.2 pH Stability of MAAs .............................................................................................. 159 12.6.3 Photostability and Photoreactivity of MAAs ........................................................... 160
12.7 Biological Activities of MAAs ............................................................................................. 160 12.7.1 Biological Activities of MAAs in Cell Culture: UV Protection ............................... 160 12.7.2 Biological Activities of MAAs as Topical Sunscreens ............................................. 161 12.7.3 Bioavailability and Absorption of MAAs ................................................................ 162
12.8 Conclusions and Future Work ............................................................................................... 162 Acknowledgments .......................................................................................................................... 163 References ...................................................................................................................................... 163
and hyperlipoproteinemia in cardiovascular disease (CVD), as well as breast and colon carcinogenesis. Coincident with the growing body of evidence elucidating the ef’cacy of edible macroalgae and their constituents in reducing the risk of chronic disease in animal models, such as mammary (Yamamoto et al., 1987; Teas et al., 1984), intestinal (Lee and Sung, 2003; Yamamoto and Maruyama, 1985), and skin carcinogenesis (Yamamoto et al., 1986; Higashi-Okai et al., 1999), is the rapidly expanding literature elucidating the endogenous antioxidant activities of marine macroalgae (reviewed by Yuan, 2007). Macroalgal antioxidant constituents include cellular enzymatic defenses (e.g., superoxide dismutase, glutathione reductase); aqueous and lipophilic molecules including L-ascorbic acid, glutathione (GSH), carotenoids, tocopherols, and chlorophyll derivatives (e.g., chlorophyll-a, pheophytin a); as well as secondary small molecule metabolites such as ™avan3-ols, phenolic acids, lignans, phlorotannins (phloroglucinol polymers) in brown macroalgae, and the UV-absorbing sunscreen mycosporine-like amino acids (e.g., mycosporine-glycine and shinorine; MAAs) in red marine macroalgae.
