Biomaterials from the sea: Future building blocks for biomedical applications

Abstract

Marine resources have tremendous potential for developing high-value biomaterials. The last decade has seen an increasing number of biomaterials that originate from marine organisms. This field is rapidly evolving. Marine biomaterials experience several periods of discovery and development ranging from coralline bone graft to polysaccharide-based biomaterials. The latter are represented by chitin and chitosan, marine-derived collagen, and composites of different organisms of marine origin. The diversity of marine natural products, their properties and applications are discussed thoroughly in the present review. These materials are easily available and possess excellent biocompatibility, biodegradability and potent bioactive characteristics. Important applications of marine biomaterials include medical applications, antimicrobial agents, drug delivery agents, anticoagulants, rehabilitation of diseases such as cardiovascular diseases, bone diseases and diabetes, as well as comestible, cosmetic and industrial applications.

Keywords: Biological properties; Biomedical applications; Marine biomaterials; Marine biopolymers; Marine organisms.

Graphical abstract

Fig. 1

A) Structural formula of chitin and chitosan; B) Monosaccharides in glycosaminoglycans; C) Chemical structures of different forms of carrageenan; D) Putative anti-inflammatory mechanisms of fucoidan; E) Collagen extraction process for producing acid-soluble and pepsin-soluble marine collagen. Tissue homogenization is conducted with the aim of size reduction via physical methods and mild chemical pretreatment. Ethylenediamine tetra-acetic acid or HCl is then employed to demineralize the raw materials to facilitate extraction. Acidic solutions (e.g. CH₃COOH) are subsequently used for dissolving the demineralized collagen to complete the extraction process. Pepsin is co-cultured with the mixture for eradication of non‐collagenous components. Finally, the soluble collagen is processed via lyophilization by mixing the collagen pellets, CH₃COOH and H₂O. (A is reproduced from Ref. [33] with permission from the publisher; B is reproduced from Ref. [34] with permission from the publisher; C is reproduced from Ref. [35] with permission from the publisher; D is reproduced from Ref. [36] with permission from the publisher; E is reproduced from Ref. [37] with permission from publisher).

Fig. 2

Marine enzymes and protein-based bioadhesives. A) Schematic of the reaction mechanism of l-asparaginase. B) Monomeric units of natural-derived eumelanin and polydopamine melanin (PDAM). i) dopamine (DA); and ii) DOPA, DHI; iii) DHICA; and iv) the porphyrin-like tetramer. C) Schematic of MAPs and their functional location in a byssal plaque. D) Schematic of the adhesive mechanism of catechols. As a DOPA analog, catechols are considered significant groups for wet adhesion because they possess strong bidentate binding ability toward mineral oxide surfaces. (A is reproduced from Ref. [153] with permission from the publisher; B is reproduced from Ref. [154] with permission from publisher; C is reproduced from Ref. [155] with permission from the publisher; D is reproduced from Ref. [156] with permission from the publisher).

Fig. 3

Chemical structures of marine secondary metabolites. (A) The core of mycosporine-like amino acids (MAAs) is composed of a cyclohexenone, or a cyclohexenimine ring conjugated to an amino acid residue or its imino alcohol; (B) MAA precursor 4-deoxygadusol and common MAAs. The latter include mycosporine-glycine, mycosporine-2-glycine, shinorine, palythine and porphyra-334. The maximum absorbance values of these molecules are included. (A, B are reproduced from Ref. [222] with permission from the publisher).

Fig. 4

Marine skeleton with hierarchical and porous architecture applied for tissue engineering and drug delivery system, including sea urchin, cuttlebone, coral with interconnected porous structures and seashells with dense lamellar structure (reproduced from Ref. [223] with permission from the publisher).

Fig. 5

(A) Images of the scleractinian coral Acropora digitifera. (B) SEM images of ultrastructural features of the coral Balanophyllia europaea. (C) Sectional view of calcium carbonate spines derived from the sea urchin Heterocentrotus mammillatus. (D) SEM images of the inner structures of sea urchin spines (A,B are reproduced from Ref. [227] with permission from the publisher; C,D are reproduced [226] from with permission from the publisher).

Fig. 6

(A) Optical image of a Patella pellucida shell that reflects light. (B) Optical image of reflection from a single stripe. (C,D,E) Types of microstructures observed in the shell of blue-rayed limpet. (F,G) Macroscopical and microscopical views of Tridacna maxima and T. derasa. (F) Top view of two T. maxima approximately 4–5 cm in length. (G) Transmission electron micrograph of a T. derasa iridocyte in cross section. (A,B,C,D,E are reproduced from Ref. [236] with permission from the publisher; F,G are reproduced from Ref. [238] with permission from the publisher).

Fig. 7

(A) Antimicrobial peptides (AMPs) kill bacteria by inducing membrane damage and/or internalization. An alternative antibacterial mechanism of AMPs is intracellular targeting. Some AMPs act on intracellular targets by inhibiting cell wall synthesis, nucleic acid binding and synthesis, protein production and enzyme activity. (B) Schematic of crosslinking reactions between 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride (EDC) and hexamethylene diisocyanate (HMDI) crosslinking agents. (C) Various forms in which chitin and chitosan constructs can be fabricated. (D) Gelatin used for bone tissue repair. (A is reproduced from Ref. [298] with permission from publisher; B is reproduced from Ref. [299] with permission from publisher; C is reproduced from Ref. [300] with permission from publisher; D is reproduced from Ref. [301] with permission from publisher).

Fig. 8

A) Properties of bioink in 3D bioprinting. B) The structure of polyunsaturated fatty acids and originated oils. C) Interrelations between polysaccharides of marine origin and drug delivery systems for advanced therapeutic applications. (A is reproduced from Ref. [326] with permission from the publisher; B is reproduced from Ref. [327] with permission from the publisher; C is reproduced from Ref. [328] with permission from the publisher).

Fig. 9

A) New biomedical uses of coral skeletons. B) Purported cardioprotective mechanisms associated with fish and fish oil-derived n-3 PUFAs. C) Effect of marine-derived materials on bone metabolism via up-regulation of osteoblastogenesis and downregulation of osteoclastogenesis. Some are directly involved in osteoblastogenesis by increasing the expression of Runx2, BMP and other transcription factors. Others are dependent on the regulation of cytokine production (IL-6 and TNF). Marine-derived compounds suppress osteoclastogenesis through downregulating the expression of RANKL, NFATc1 and TRAP) (A is reproduced from Ref. [329] with permission from the publisher; B is reproduced from Ref. [330] with permission from the publisher; C is reproduced from Ref. [331] with permission from the publisher).