Phlorotannin isolated

Heo, S., Ko, S., Cha, S., Kang, D., Park, H., Choi, Y., Kim, D., Jung, W., and Jeon, Y. (2009a). Effect of phlorotannins isolated from Ecklonia cava on melanogenesis and their protective effect against photo-oxidative stress induced by UV-B radiation. Toxicol. In Vitro 23, 1123-1130. 

FIGURE 8.1 Structures of phlorotannins isolated from marine brown algae. 

Shibata, T., Ishimaru, K., Kawaguchi, S., Yoshikawa, H., and Hama, Y. (2008). Antioxidant activities of phlorotannins isolated from Japanese Laminariacea. /. Appl. Phycol. 20, 705-711. 

Shibata T, Ishimaru K, Kawaguchi S, Yoshikawa H, Hama Y. Antioxidant activities of phlorotannins isolated from Japanese Laminariaceae. J Appl Phycol. 2008 20(5) 705-711. 

Yoon NY, EomTK, Kim MM, Kim SK. Inhibitory effect of phlorotannins isolated from Ecklonia cava on mushroom tyrosinase activity and melanin formation in mouse B16F10 melanoma cells. 

Pavia H, Cervin G, Lindgren A, Aberg P (1997) Effects of UV-B radiation and simulated herbivory on phlorotannins in the brown alga Ascophyllum nodosum. Mar Ecol Prog Ser 157 139-146 Pawlik JR (1993) Marine invertebrate chemical defenses. Chem Rev 93 1911-1922 Pettit GR, Kamano Y, Herald CL, Tuinman AA, Boettner FE, Kizu H, Schmidt JM, Baczynskyj L, Tomer KB, Bontems RJ (1987) The isolation and structure of a remarkable marine animal antineoplastic constituent dolastatin 10. J Am Chem Soc 109 6883-6885 Pfander H, Stoll H (1991) Terpenoid glycosides. Nat Prod Rep 8 69-95... 

Suzuki Y, Takabayashi T, Kawaguchi T, Matsunaga K (1998) Isolation of an allelopathic substance from the crustose coralline algae, Lithophyllum spp., and its effect on the brown alga, Laminaria religiosa Miyabe (Phaeophyta). J Exp Mar Biol Ecol 225 69-77 Svensson CJ, Pavia H, Toth G (2007) Do plant density, nutrient availability, and herbivore grazing interact to affect phlorotannin plasticity in the brown seaweed Ascophyllwn nodosum. Mar Biol (in press), doi 10.1007/s00227-007-0649-5 Swanson AK, Druehl LD (2002) Induction, exudation and the UV protective role of kelp phloro-tannins. Aquat Bot 73 241-253... 

Examples of other anti-HIV compounds also included four phlorotannin derivatives, eckol, 8,8 -dieckoI, 8,4 -dieckoI and phlorofucofiiro-eckol A, isolated from the brown alga Ecklonia cava [65]. Among these compounds, 8,8 -dieckol and 8,4 -dieckol exhibited an inhibitory effect on HIV-1 RT and protease. An enzyme kinetic assay... 

Ryu, B., Li, Y., Qian, Z. J., Kim, M. M., and Kim, S. K. (2009). Differentiation of human osteosarcoma cells by isolated phlorotannins is subtly linked to COX-2, iNOS, MMPs, and MARK signaling Implication for chronic articular disease. Chem. Biol. Interact. 179, 192-201. 

Tannins are naturally occurring water-soluble polyphenolic compoimds, and it has been reported that they show their anti-HIV activity by inhibiting polymerase and ribonuclease activities of HIV-1 RT. Phlorotannins are tannin derivatives which contain several phloroglucinol imits linked to each other in different ways and formed by the polymerization of phloroglucinol (1,3,5-trihydroxybenzene) monomer units and biosynthesis through the acetate-malonate pathway. So far, phlorotannins mostly have been isolated from red and brown alga. Numerous bioactivities of phlorotannins have been reported up to date such as antioxidant, antiinflammatory, antibacterial, and anti-MMP activities (Kim et al., 2006 Nagayama et al., 2002). 

Sugiura, Y., Matsuda, K., Yamada, Y., Nishikawa, M., Shioya, K., Katsuzaki, H., Imai, K., and Amano, H. (2006a). Isolation of a new anti-allergic phlorotannin, phlorofucofuroeckol-B, from an edible brown alga, Eisenia arborea. Biosci. Biotechnol. Biochem. 70,2807-2811. 

Fucodiphlorethol G (Fig. 33.3), a new compoimd isolated from the methanol extract of E. cava, a brown alga, collected offshore in Jeju Island by Ham et al. (2007). By the examination of and NMR data, it was foimd that the structure of the compoimd is similar to that of trimeric phlorotannin triphlorethol-A (Fig. 33.3). Although these studies evidenced that these compoimds can stimulate osteoblast differentiation at various stages, there is no clear demonstration of whether the phlorotannin compound, Fucodiphlorethol G, has direct effect on osteoblast differentiation. 

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