Document of bibliographic reference 331114

BibliographicReference record

Type

Bibliographic resource

Type of document

Journal article

BibLvlCode

AS

Title

Chemical defense of Mediterranean sponges Aplysina cavernicola and Aplysina aerophoba

Abstract

The Mediterranean sponges Aplysina aerophoba and A. cavernicola accumulate brominated isoxazoline alkaloids including aplysinamisin-1 (1), aerophobin-2 (2), isofistularin-3 (3) or aerothionin (4) at concentrations up to 10% of their respective dry weights. In laboratory feeding experiments employing the polyphagous Mediterranean fish Blennius sphinx crude extracts of both Aplysina sponges were incorporated into artificial fish food at their physiological concentrations (based on volume) and offered to B. sphinx in choice feeding experiments against untreated control food. In addition to the Aplysina sponges, extracts from nine other frequently occurring Mediterranean sponges were likewise included into the experiments. Both Aplysina species elicited strong feeding deterrence compared to the other sponges tested. Bioassay-guided fractionation of A. cavernicola yielded the isoxazoline alkaloids aerothionin (4) and aplysinamisin-1 (1) as well as the 3,4-dihydroxyquinoline-2-carboxylic acid (8) as major deterrent constituents when tested at their physiological concentrations as present in sponges. Aeroplysinin-1 (5) and dienone (6), however, which are formed in A. aerophoba and A. cavernicola from isoxazoline precursors through bioconversion reactions upon tissue injury showed no or only little deterrent activity. Fractionation of a crude extract of A. aerophoba yielded aerophobin-2 (2) and isofistularin-3 (3) as major deterrent constituents against B. sphinx. We propose that the isoxazoline alkaloids 1-4 of Mediterranean Aplysina sponges as well as the 3,4-dihydroxyquinoline-2-carboxylic acid (8) (in the case of A. cavernicola) act as defensive metabolites against B. sphinx and possibly also against other predators while the antibiotically active bioconversion products aeroplysinin-1 (5) and dienone (6) may protect sponges from invasion of bacterial pathogens.

WebOfScience code

https://www.webofscience.com/wos/woscc/full-record/WOS:000220790400022

Bibliographic citation

Thoms, C.; Wolff, M.; Padmakumar, K.; Ebel, R.; Proksch, P. (2004). Chemical defense of Mediterranean sponges Aplysina cavernicola and Aplysina aerophoba. Zeitschrift für Naturforschung. C, A journal of biosciences 59(1-2): 113-122. https://dx.doi.org/10.1515/znc-2004-1-222

Topic

Marine

Is peer reviewed

true

Access rights

open access

Is accessible for free

true