Amphidinium species

Oguchi, K., Tsuda, M., Iwamoto, R., Okamoto, Y, Kobayashi. J., Fukushi, E., Kawabata, J., Ozawa, T Masuda, A., Kitaya, Y, and Omasa, K. (2008) Iriomoteolide-3a, a cytotoxic 15-membered macrolide from a marine dinoflagellate Amphidinium species. /. Org. Chem., 73,1567-1570. 

Increased synthesis of MAAs by exposure to high intensity artificial visible light also occurs in the Antarctic diatom Thalassiosira weissflogii, the prasinophyte Pyramimonas parkae, and most markedly in the dinoflagellate Amphidinium carterae (six-fold increase over control).171 However, high visible light exposure does not affect the MAA content of two other unicellular algae, Dunaliella tertiolecta (Chlorophyta) and Isochrysis sp. (Haptophyta). Supplemental exposures with UVA and UVB in combination and alone result in a variety of species-specific responses. 

Carlucci and Bowes [29] showed that vitamin production in phytoplankton algae was attributed to release during exponential growth and upon cell death and lysis in old cultures. Vitamin utilization was readily observed in cultures of two species S. costatum produced utilizable biotin for Amphidinium carterae. The amount of utilizable vitamin and the rate at which it was exuded depended on the algal species and conditions of culturing. Aaronson et al. [149] showed that when O. danicus (chrysophyceae) was grown on a defined medium the cells excreted a number of vitamins including riboflavin, vitamin E and nicotinic acid in addition to four amino acids. Swift [150] published an excellent review of phytoplankton production, excretion and utihzation of vitamins. 

Among the many linear molecules isolated from dinoflagellates may be included the amphidinols (AMs). These are polyenic and polyhydroxylated derivatives with very condensed carbon skeletons, usually composed of 60-73 atoms, and carrying some methyl or methylene substitutions the first term of the series (AMI) is the only one which carries a sulfate group. Seven amphidinols (AMl-AM7) are currently known, all isolated from species of the genus Amphidinium, particularly A. carterae (New Zealand) and A. klebsii (Japan). All the amphidinols are... 

With 59 carbon atoms, amphidinol 7 (AM7) is currently the shortest representative of the series. Isolated from the species Amphidinium klebsii (NIES 613), it has the same hemolytic and fungicidal properties as AM3, although its activity is weaker (Morsy et al, 2005, 2006). 

Colopsinols A-E are also linear polyhydroxypolyenes, but are aU glycosides (P-o-glucose). They have a sulfate group and were aU isolated from an unspecified species of Amphidinium. Colopsinols A, B, and D have two glucose tmits, whereas colopsinols C and E have only one unit (Kobayashi et al, 1999 Kubota et al, 1999, 2000a). 

Luteophanol A is a polyhydroxylated and sulfated Unear derivative isolated from another species of Amphidinium (strain Y-52) Uving symbiotically with the platyhelminth Pseudoaphanostoma luteocoloris harvested in Okinawa. This compoimd, related to amphidinols, is only moderately antimicrobial, as are two other non-sulfated analogs, luteo-phanols B and C (Doi et al., 1997 Kubota et al., 1998). All of these compoimds are described in the chapter on dino-flagellates (see Chapter 11). 

Isolated from a spedes of Amphidinium assodated with a species of Amphiscolops, amphezonol A is a polyhydroxy-lated derivative with a number of carbon atoms (62) similar to that of luteophanols. It was isolated together with amphidinolides G and H. Amphezonol A has no specific biological adivity (Kubota et al., 2006). 

Also isolated from a symbiosis between species of Amphidinium and Amphiscolops, symbiodinolide consists of a long-chain polyhydroxylated derivative with a 62-member macrolide. Symbiodinolide presents obvious similarities with zooxanthellatoxins (see Chapter 11), it activates N-type Ca channel (Kita et al., 2007)... 

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