Fig 1.
Current state of the art concerning distribution of chitin in the phylum porifera.
Fig 2.
Specimens of A. wolffgangi (a) and E. gibbosa (c) in their natural environments. Washed with deionized water of the freeze-dried skeletons of A. wolffgangi (b) and E. gibbosa (d) which have been used for chitin isolation in this study.
Fig 3.
Step-by-step scheme showing procedure for isolation of chitinous fibers from the skeletons of A. wolffgangi (left line) and E. gibbosa (right line).
Fig 4.
Spicule-free, colorless 3D scaffold obtained from A. wolffgangii (a) and E. gibbosa (d) according to the isolation procedure represented in Fig 3. Microstructural features of selected skeletal fibers of A. wolffgangii (marked with arrows) (b) and E. gibbosa (e) prior and after HF-treatment (c and f, respectively) are well visible on the corresponding light microscopy images.
Fig 5.
SEM imagery of the purified A. wolffgani (a) and E. gibbosa (d) skeleton’s fragments prior (b and e, respectively) and after demineralization procedure (c and f, respectively). Well visible spicules are marked with arrows.
Fig 6.
Purified skeletal fibers of A. wolffgangi (a) and E. gibbiosa (c) after CFW staining observed in light microscopy (a, c) and fluorescence microscopy (b and d) modus, respectively.
Fig 7.
FT-IR spectra of chitin isolated from A. wolffgangi and E. gibbosa demosponges in comparison with the of α-chitin standard.
Fig 8.
Raman spectroscopy of the chitinous scaffolds isolated from A. wolffgangi and E. gibbosa demosponges in comparison with α-chitin standard.
Fig 9.
Visualization of the chitinase digestion test using white light microscopy.
Chitinase digestion of purified and completely demineralized selected skeletal fiber isolated from A. wolffgangi and E. gibbosa prior (a and c, respectively) and after 3 h of chitinase treatment (b and d, respectively).
Fig 10.
Comparative ESI-MS analyses from the glucosamine standard (a), and of the hydrolysed chitin from the A. wolffgangi (b) and E. gibbosa (c).
Fig 11.
Schematic view of the possible uses of Poecilosclerida sponges including A. wolffgangi and E. gibbosa species.