Antioxidant activities of minor pigments of sea urchins (1–5) and synthetic naphthazarins (7–13) were evaluated and compared with echinochrome A (6) using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) scavenging assays. Structure-activity relationships showed that the antioxidant activities of the tested compounds depended on the number and positions of hydroxyl groups. Compounds bearing 3 or 2 hydroxyl groups on a naphthazarin core (5,8-dihydroxy-1,4-naphthoquinone) were the most active in both assays. Echinochrome A (6) (IC50 7.0 μM) and its monomethyl ethers 7 (IC50 15.0 μM) and 8 (IC50 15.0 μM) displayed stronger activities than Trolox (IC50 16.0 μM) in the DPPH and ABTS assays (TE = 3.41, 2.35, and 2.35 mM, respectively). Compounds with either one or without hydroxyl groups on a naphthazarin core displayed activities significantly lower than Trolox in both assays. These results suggest that hydroxylated naphthazarin pigments of sea urchins have a potential use as natural antioxidants.
AndersonH.A., MathiesonJ.W., ThomsonR.H. (1969) Distribution of spinochrome pigments in echinoids. Comparative Biochemistry and Physiology, 28, 333–345.
2.
UtkinaN.K., ShchedrinA.P., MaksimovO.B. (1976) A new binaphthoquinone from Strongylocentrotus intermedius. Chemistry of Natural Compounds, 12, 387–389.
3.
MischenkoN.P., FedoreyevS.A., PokhiloN.D., AnufrievV.P., DenisenkoV.A., GlazunovV.P. (2005) Echinamines A and B, first aminated hydroxynaphthazarins from the sea urchin Scaphechinus mirabilis. Journal of Natural Products, 68, 1390–1393.
4.
MischenkoN.P., FedoreyevS.A., BagirovaV.L. (2003) Histochrome: a new original domestic drug. Pharmaceutical Chemistry Journal, 37, 48–52.
5.
AnufrievV.P., ElyakovG.B., PolonicS.G., PokhiloN.D., ShestakO.P., YakubovskayaA.Y., OsadchiyS.A., TolstikovG.A., ShultzE.E. (2006) A method of preparation of 5,8-dihydroxy-2,6,7-trimethoxy-3-ethyl-1,4-naphthoquinone. RF Patent No. 2277083. Bulletin Izobreteniy, 15.
6.
PolonikS.G., PokhiloN.D., MakhankovV.V., AnufrievV.P. (2008) Acid-catalyzed demethylation of echinochrome trimethyl ether. Chemistry of Natural Compounds, 44, 93–94.
7.
HatateH., MurataH., HamaY., TanakaR., SuzukiN. (2002) Antioxidative activity of spinochromes extracted from shells of sea urchins. Fisheries Science, 68, 1641–1642.
8.
KuwaharaR., HatateH., YukiT., MurataH., TanakaR., HamaY. (2009) Antioxidant property of polyhydroxylated naphthoquinone pigments from shells of purple sea urchin Anthocidaris crassispina. LWT - Food Science and Technology, 42, 1296–1300.
9.
ZhouD-Y, QinL., ZhuB-W, WangX-D, TanH., YangJ-F, LiD-M, DongX-P, WuH-T, SunL-M, LiX-L, MurataY. (2011) Extraction and antioxidant property of polyhydroxylated naphthoquinone pigments from spines of purple sea urchin Strongylocentrotus nudus. Food Chemistry, 129, 1591–1597.
10.
KoltsovaE.A., ChumakG.N., MaksimovO.B. (1977) Quinoid pigments of Ehinodermata III. Minor pigments of sea urchin Strongylocentrotus nudus. Chemistry of Natural Compounds, 13, 174–177.
11.
MischenkoN.P., FedoreyevS.A., GlazunovV.P., DenisenkoV.A., KrasovskayaN.P., GlebkoL.I., MaslovL.G., DmitrenokP.S., BagirovaV.L. (2004) Isolation and identification of impurities in the parent substance of echinochrome and the drug Histochrome. Pharmaceutical Chemistry Journal, 38, 50–53.
12.
LebedevA.V., IvanovaM.V., KrasnovidN.I. (1999) Interaction of natural polyhydroxy-1,4-naphthoquinones with superoxide anion-radical. Biochemistry (Moscow), 64, 1273–1278.
13.
MooreR.E., SinghH., ScheuerP.J. (1966) Isolation of eleven new spinochromes from Echinoids of the genus Echinothrix. Journal of Organic Chemistry, 31, 3645–3650.
14.
LebedevA.V., IvanovaM.V., LevitskyD.O. (2005) Echinochrome, a naturally occurring iron chelator and free radical scavenger in artificial and natural membrane systems. Life Sciences, 76, 863–875.
15.
DonaldsonN. (1960) The chemistry and technology of naphthalene compounds.Arnold Ltd., London (England), 1–548.
16.
ChizhovaA.Y., KocherginaT.Y., AnufrievV.P., DenisenkoV.A., GlazunovV.P. (1999) The chemistry of naphthazarin derivatives 3. Synthesis of the dideoxy analog of islandoquinone. Russian Chemical Bulletin, 48, 938–943.
17.
GlazunovV.P., TchizhovaA.Y., PokhiloN.D., AnufrievV.P., ElyakovG.B. (2002) First direct observation of tautomerism of monohydroxynaphthazarins by IR-spectroscopy. Tetrahedron, 58, 1751–1757.
18.
GlazunovV.P., TchizhovaA.Y., ShuvalovaM.I., AnufrievV.P. (2001) Chemistry of naphthazarin derivatives 7. Determination of structures of substituted 2,6(7)-dihydroxynaphthazarins by UV and IR spectroscopy. Russian Chemical Bulletin, 50, 88–94.
19.
MalinovskayaG.V., TchizhovaA.Y., AnufrievV.P. (1999) Chemistry of naphthazarin derivatives 4. A simple preparative synthesis of mompain. Russian Chemical Bulletin, 48, 1010–1011.
20.
MathiesonJ.W., ThomsonR.H. (1971) Naturally occurring quinones. Part XVIII. New spinochromes from Diadema antillarum, Spatagus purpureus, and Temnopleurus toreumaticus. Journal of the Chemical Society C: Organic, 153–160.
21.
GlazunovV.P., YakubovskayaA.Y., PokhiloN.D., BochinskayaN.V., AnufrievV.P. (2003) Chemistry of naphthazarin derivatives 9. Direct observation of prototropic tautomerism of (poly)hydroxynaphthazarins by IR spectroscopy. Russian Chemical Bulletin, 52, 198–207.
22.
GlazunovV.P., TchizhovaA.Y., ShestakO.P., SopelnyakG.I., AnufrievV.P. (2001) Chemistry of naphthazarin derivatives 8. Determination of structures of substituted 2-hydroxy-6(7)-methoxynaphthazarins and 7(8)-hydroxypyranonaphthazarins by IR spectroscopy. Russian Chemical Bulletin, 50, 95–100.
23.
YamamotoY., NatsubaraH., KinoshitaY., KinoshitaK., KoyamaK., TakahashiK., AnmadjiamV., KurokawaT., YoshimuraI. (1996) Naphthazarin derivatives from cultures of the lichen Cladonia cristatella. Phytochemistry, 43, 1239–1242.
24.
PejinB., IodiceC., TommonaroG., De RosaS. (2008) Synthesis and biological activities of thio-avarol derivatives. Journal of Natural Products, 71, 1850–1853.
