DIFFERENT ALLOCATION OF SECONDARY METABOLITES IN THESPONGE OCEANAPIA SP. AND ECOLOGICAL IMPLICATIONS
Peter Schupp1, C. Eder1, V. Paul2 andP. Proksch1.
1Lehrstuhl f. Pharmazeutische Biologie, University of Wuerzburg,97082 Wuerzburg; Germany.
2UOG Marine Laboratory, Mangilao, Guam 96923, U.S.A.
Oceanapia sp. from Truk Lagoon is a very distinctive sponge.It consists of an enlarged basal root that is completely buried in thesediment, a fistule that reaches above the sediment and a translucent capitumon top of the fistule. We isolated the two major compounds kuanoniamineC and D from the crude extract. The concentrations of kuanoniamine C andD increased from the basal root to the translucent capitum. The lowestconcentrations of the alkaloids were found in the basal root with 0.3%of dry mass for kuanoniamine C and 0.1% of dry mass for kuanoniamine D.The fistules showed a four fold increase of the metabolites. The highestconcentrations were found in the translucent capitum with 5% of dry massfor kuanoniamine C and 1.75% of dry mass for kuanoniamine D.The angelfishPomacanthus imperator was deterred by the crude extract in laboratoryfeeding assays. The pure compounds kuanoniamine C and D revealed an evengreater deterrent effect when tested against natural fish communities inthe field.