Carotenoids seaweeds

Miyashita, K. and Hosokawa, M. (2008). Beneficial health effects of seaweed carotenoid, fucoxanthin. In "Marine Nutraceuticals and Functional Foods", (C. Barrow and... 

Extraction of total carotenoids has been reported by several authors using different solvents or solvent combinations. Most researchers use methanol and/or acetone as the preferred solvents to recover total carotenoids. General HPLC protocols followed for identification of various seaweed carotenoids, fucoxanthin in particular, are presented in Table 26.1. 

Several studies have investigated the role of dietary factors in prostate cancer risk, but results appear inconsistent. Significant effects have not been detected for dietary soya products certain vegetables, beans, fruit, rice and seaweed appear to be protective in some studies, while another has shown no protective effect from seaweed or vegetable consumption. In addition, a number of other risk factors have been shown to be associated with an increased risk of this cancer, including meat and dairy products and carotenoids. 

Seaweed lipid/carotenoid extraction, analysis of total lipid, lipid... 

Seaweed Lipid/Carotenoid Extraction, Analysis of Total Lipid, Lipid Classes and Fatty Acids... 

TABLE 26.1. HPLC protocols used for separation of seaweed related carotenoids. 

Various carotenoids brown and red seaweeds Reverse Phase, C18 column Methanol and Water (9 1 v/v) isocratic Normal phase, Silica gel column Tetrahydrofuran and hexane (35 65 v/v) isocratic Maoka et al., 2002... 

Although the marine animals have been exploited thoroughly for food and other byproducts, their plant counter parts have not been exploited for food to the same extent, barring some seaweeds like Porphyra (nori) and Laminaria (konbu). Unlike terrestrial counter parts, marine plants have not been looked upon as important substrates for further processing of their lipids. In this section, seaweed lipids have been classified for convenience into different categories, viz., general fatty acids, conjugated fatty acids, carotenoids (fuco-xanthin), and sterols (fucosterol). 

The major carotenoids in seaweeds include p-carotene, lutein, violoxanthin, neoxanthin, and zeaxanthin in green seaweeds (chlorophytes) a- p-caro-tene, lutein, and zeaxanthin in red seaweeds (rhodophytes) and, fucoxanthin, p-carotene, and violoxanthin in brown seaweeds (phaeophytes). Fucoxanthin, apart from being the most characteristic pigment of brown seaweeds, is also one of the most abundant carotenoids in nature (Matsuno, 2001 Hosokawa et al., 2004). 

The principle problem of algae as sources of lipids is their high water (70-90%) and low lipid content. Despite their lipid content (-7%), the fatty acids of marine algae have aroused considerable interest among researchers for their nutritional value to other marine organisms, occurrence of bioactive conjugated fatty acids, and potential medical applications. The annual production of carotenoids from seaweeds is estimated to be approximately 100 million tons, of which fucoxanthin, the main carotenoids from brown seaweed, contributes more than 10% (Matsuno, 2001). 

I), nor-carotenoids and sesquiterpene alcohols were identified (19). An essential oil of cultivated conchocelis-filaments of the seaweed contained cubenol, phytol, palmitic acid and the long-chain fatty aldehydes such as tetradecanal, pentadecanal, (Z, Z)-7,... 

Kageyama A, Yokohama Y, Shimura S and Ikawa T (1977) An efficient excitation energy transfer from a carotenoid, siphonaxanthin to CM a observed in a deep-water species of chlorophycean seaweed. Plant Cell Physiol 18 477-480 Kamen MD (1986) On creativity of eye and ear A commentary on the career of TW Engelmann. Proc Amer Philos Sci 130 232-246... 

Carotenoids fucoxanthin Stimulation of UCPl, resulting in metabolic thermogenesis Seaweed U. pirmatifida Possible antiobesity effect and reduced risk of type II diabetes Maeda et al., 2005... 

Over the past few decades, several studies have focused on fucoxanthin contained in seaweed. Fucoxanthin, a characteristic carotenoid of brown algae, has a unique structure that includes an unusual allenic bond and 5,6-monoepoxide. Wakame (LI. pinnatifida), an edible seaweed, is rich in fucoxanthin. 

Miyashita, K., Nishikawa, S., Beppu, F., Tsukui, T., Abe, M., and Hosokawa, M. (2011). The allenic carotenoid fucoxanthin, a novel marine nutraceutical from brown seaweeds. /. Sci. Food Agric. 91,1166-1174. 

Seaweeds have to survive in a highly competitive environment subjected to light fluctuation, oxygen exposure, dehydration process, etc. therefore, they develop defense strategies in different metabolic pathways. Thus marine organisms are rich sources of structurally diverse bioactive minor compounds such as carotenoids, polyphenols, minerals, vitamins, and fatty acids (Cardozo et ah, 2007). Besides, they possess other major compoimds such as complex carbohydrates and protein, from which bioactive sulfated polysaccharides and peptides can be isolated. 

Seaweeds are a good source of some water- (Bj, B2, B,2, C) and fat-soluble (P-carotene with vitamin A activity, vitamin E) vitamins. To ensure that the adequate intake of all vitamins is received in the diet, people (especially peopleon specialdiet, strict vegetarians, and vegans) can consume foods enriched with vitamins, for example, in the form of functional foods with vitamins as nutraceuticals, extracted from natural sources such as seaweeds. Seaweed vitamins are important not only due to their biochemical functions and antioxidant activity but also due to other health benefits such as decreasing of blood pressure (vitamin C), prevention of cardiovascular diseases (P-carotene), or reducing the risk of cancer (vitamins E and C, carotenoids). 

Seaweeds are generally a good source of some B group vitamins (Bi, E2, B12). Other vitamins of B-complex are present too, but only in low or trace amounts (niacin, Bg, biotin, folates). Certain seaweeds contain great quantities of vitamins with antioxidant activity, vitamins C and E, and the provitamin forms of vitamin A, carotenoids. 

The compoimds which are responsible for antioxidant activity in seaweed include vitamin E (a-tocopherol), carotenoids (p-carotene), and vitamin C (ascorbic acid), and partially vitamin Bi and niacin. 

Carotenoids are natural pigments synthesized by plants and some microorganisms. Humans and animals are not able to synthesize and need to acquire them by alimentation [1]. These compounds are widely distributed in fruits, flowers, roots, seaweeds, invertebrates, fishes, birds, bacteria, fungi, and yeasts [2-4]. They are responsible for the red, yellow, and orange colors, but green, purple, or blue color could be obtained when carotenoids are botmd with some proteins [1]. Such molecules act as photosynthesis aid and for the photoprotection of their hosts [2-4]. Due to this, it is used in food and feed as colorant, flavoring, and nutritional supplement, being source of provitamin A. 

---