Figure 1.
a) Well developed Oscarella balibaloi (Ob) specimen in the vicinity of two common Oscarella species: Oscarella lobularis (Ol) and Oscarella tuberculata (Ot). b) Oscarella balibaloi (Ob) growing on demosponge Aplysina cavernicola (Ac).
Figure 2.
Temporal variation of the bioactivity in relation to the seawater temperature.
a) Variation of Oscarella balibaloi bioactivity (EC50 in µg.mL−1) over two years (Kruskal-Wallis test: H KW(20;109) = 78.86; p<0.0001) in relation to the seasonal fluctuations of the seawater temperature (°C). Vertical bars represent standard errors (Mean ± 0.95 SE). b) Effect of the seawater temperature on the bioactivity of Oscarella balibaloi. The bioactivity is indicated in EC50 (µg.mL−1). Boxes represent Mean ± 0.95 SE and vertical bars Mean ± 0.95 Confidence Interval. Significant effect indicated by Kruskal-Wallis test: H KW(4;106) = 27.35, p<0.0001.
Figure 3.
Metabolic fingerprints of Oscarella balibaloi.
Representative LC-MS chromatogram (a) of Oscarella balibaloi and three metabolic phenotypes (1, 2 and 3) indicated by their respective ELSD chromatograms (b, c, d). On the LC-MS and LC-ELSD chromatograms major m/z are indicated above peaks.
Figure 4.
Relationship between the bioactivity and metabolic phenotypes of Oscarella balibaloi.
The scatterplot of the metabolic fingerprint data set was analyzed by PCA. The PC1 explains 70.2% of variability and PC2 explains 11.3%.
Table 1.
Secondary metabolite composition of the three distinct metabolic phenotypes of Oscarella balibaloi.
Figure 5.
Influence of biotic interactions on Oscarella balibaloi bioactivity.
a) Interactions with two favorite sponge species, Spongia officinalis (n = 32) and Aplysina cavernicola (n = 3 4) versus rocky substrate (control, n = 26) were tested. Boxes represent Mean ± 0.95 SE and vertical bars Mean ± 0.95 Confidence Interval. Significant effect indicated by Kruskal-Wallis test: H KW(2;90) = 2.61, p<0.27. b) Relationship between metabolic phenotypes and biotic interactions of Oscarella balibaloi represented by the scatterplot of the metabolic fingerprint data set. The PC1 explains 70.2% of variation and PC2 the additional 11.3%.
Figure 6.
Influence of sponge reproductive status on the bioactivity.
a) Variation of Oscarella balibaloi bioactivity (EC50 in µg.mL−1) according to reproductive stage. The effect of significance is given by Kruskal-Wallis test: H KW(2;109) = 31.48, p<0.001. b) Variation of Oscarella balibaloi bioactivity (EC50 in µg.mL−1) according to sponge sexe. The effect of significance is given by Kruskal-Wallis test: H KW(2;109) = 31.44, p<0.0001. c) Correlation between Oscarella balibaloi bioactivity (EC50 in µg.mL−1) and its reproductive effort (%): R = 0.49, p = 0.0008. Boxes represent Mean ± 0.95 SE and vertical bars Mean ± 0.95 Confidence Interval.
Figure 7.
Relation between metabolic phenotypes and sponge reproductive status.
The scatterplot of the metabolic fingerprint data set was analyzed by PCA. The representation factor is the reproductive stage with the indication of the sponge sexe. The PC1 explains 70.2% of variation and PC2 the additional 11.3%.