Fertilized sea urchin eggs

Kobayashi, N. 1971. Fertilized sea urchin eggs as an indicatory material for marine pollution bioassays, preliminary experiments. Publ. Seto Mar. Biol. Lab. 18 379-406. 

The compounds isolated from the nudibranch Hexabranchus sanguineus varied with collecting location but usually included dihydrohalichondra-mide (261) and tetrahydrohalichondramide (268). Compounds 261, 263, 265, and 268 show antifungal activity and inhibit cell division in the fertilized sea urchin egg assay (218). Three cytotoxic macrolides, mycalolides A-C (269-271), were isolated from a Japanese sponge of the genus My-cale, and their structures were elucidated to be hybrids of ulapualides and halichondramide (219). 

While for the pyrrole derived lamellarins and related compounds no activity has been described, several pentacyclic lamellarins show important cytotoxic activities. Lamellarin D at a concentration of 19 pg/ml caused a 78% inhibition of cell division in the fertilized sea urchin egg assay while lamellarin C caused 15% inhibition but lamellarins A and B were inactive <85JA5492>. Lamellarins I, K and L present significant cytotoxicity against P338 and A549 cultured cell lines and lamellarins K and L also exhibit immunomodulatory activity <93AJC489>. 

In our searching for inhibitors of the cell division of fertilized sea urchin eggs from Okinawan waters [4], we have isolated a number of chemically and biologically interesting marine natural products. In this article we will discuss the isolation, structure determination and activities of the marine metabolites which have been mainly isolated in our laboratory. Syntheses of these metabolites or their congeners are also described. 

Kohamaic acids A (9) and B (10) exhibited cytotoxicity against P388 mouse leukemia cells, with an IC50 of 17 and 2.8 Xg/mL, respectively. Kohamaic acids also completely inhibited the cleavage of fertilized sea urchin eggs at a concentration of 2 Xg/mL. 

III trials in Europe) [70]. The biomedical potential of the ascidian metabolites has resulted in these primitive chordates. As part of our ongoing chemical and biological studies on Okinawan marine organisms, we investigated an ascidian Lissoclinum sp. collected off the coast of Hateruma Island. A lipophilic extract of the ascidian showed that it could inhibit the division of fertilized sea urchin eggs. 

The cytotoxicity of compounds 22-38 and 42-44 was evaluated against mouse lymphoc3dic leukemia (P388) cells. The toxicity of these compounds against fertilized sea urchin eggs was also evaluated. The results are shown in Table (2). 

Table (3). Inhibition of the first cleavage of fertilized sea urchin eggs.

Two common in-house bioassays to screen for metabolites exhibiting general cytotoxicity, the fertilized sea urchin egg cytotoxicity assay and the brine shrimp lethality assay, were used to identify bioactive diterpene metabolites in two soft coral species collected from Sodwana Bay and Ponto do Ouro respectively. Sodwana Bay specimens of Sarcophyton... 

Sepositoside A (54) is moderately toxic (LOj j =43 mg Kg by i. p. injection in mouse) (43), and showed cytotoxic activity towards bovine turbinate cells up to a level of Ipg ml (39). Both sepositoside A (54) and luzonicoside A (59) were slightly effective in the inhibition of cell division of fertilized sea urchin eggs (ca. 30% inhibition at 10 M) and showed antifungal activity. 

Haliclamines A (43) and B (44). Isolated from Haliclona sp., the structures of these reduced analogs were deduced by homonuclear and heteronuclear COSY and HMBC spectra. 43 and 44 showed a 1,3-disubstituted-3,4-dehydropiperidine moiety that is also present in saraines and isosaraines. Both compoimds not only inhibit cell division of fertilized sea urchin eggs, but also growth of L1210 (IC50 1-5 and 0.9 jug/ml, respectively) and P388 leukemia cell lines (0.75 and 0.39) [40]. 

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