Comparison of Different Methods for Spongin-like Collagen Extraction from Marine Sponges (Chondrilla caribensis and Aplysina fulva): Physicochemical Properties and In Vitro Biological Analysis

Marine Antioxidants from Marine Collagen and Collagen Peptides with Nutraceuticals Applications: A Review

Collagen peptides and marine collagen are enormous resources currently utilized. This review aims to examine the scientific literature to determine which collagen peptides derived from marine sources and which natural active antioxidants from marine collagen have significant biological effects as health-promoting nutraceuticals. Marine collagen is extracted from both vertebrate and invertebrate marine creatures. For vertebrates, this includes fish skin, bones, scales, fins, and cartilage. For invertebrates, it includes mollusks, echinoderms, crustaceans, and poriferans. The method used involved data analysis to organize information for isolating and identifying marine biocompounds with antioxidant properties. Specifically, amino acids with antioxidant properties were identified, enabling the use of hydrolysates and collagen peptides as natural antioxidant nutraceuticals. The methods of extraction of hydrolyzed collagen and collagen peptides by different treatments are systematized. The structural characteristics of collagen, collagen peptides, and amino acids in fish skin and by-products, as well as in invertebrate organisms (jellyfish, mollusks, and crustaceans), are described. The antioxidant properties of different methods of collagen hydrolysates and collagen peptides are systematized, and the results are comparatively analyzed. Their use as natural antioxidant nutraceuticals expands the range of possibilities for the exploitation of natural resources that have not been widely used until now.

Association of a Skin Dressing Made With the Organic Part of Marine Sponges and Photobiomodulation on the Wound Healing in an Animal Model

The present study aims to characterize and to evaluate the biological effects of a skin dressing manufactured with the organic part of the Chondrilla caribensis marine sponge (called spongin-like collagen (SC)) associated or not to photobiomodulation (PBM) on the skin wound healing of rats. Skin dressings were manufactured with SC and it was characterized using scanning electron microscopy (SEM) and a tensile assay. In order to evaluate its biological effects, an experimental model of cutaneous wounds was surgically performed. Eighteen rats were randomly distributed into three experimental groups: control group (CG): animals with skin wounds but without any treatment; marine collagen dressing group (DG): animals with skin wounds treated with marine collagen dressing; and the marine collagen dressing + PBM group (DPG): animals with skin wounds treated with marine collagen dressing and PBM. Histopathological, histomorphometric, and immunohistochemical evaluations (qualitative and semiquantitative) of COX2, TGFβ, FGF, and VEGF were done. SEM demonstrates that the marine collagen dressing presented pores and interconnected fibers and adequate mechanical strength. Furthermore, in the microscopic analysis, an incomplete reepithelialization and the presence of granulation tissue with inflammatory infiltrate were observed in all experimental groups. In addition, foreign body was identified in the DG and DPG. COX2, TGFβ, FGF, and VEGF immunostaining was observed predominantly in the wound area of all experimental groups, with a statistically significant difference for FGF immunostaining score of DPG in relation to CG. The marine collagen dressing presented adequate physical characteristics and its association with PBM presented favorable biological effects to the skin repair process.

The Characterization and Cytotoxic Evaluation of Chondrosia reniformis Collagen Isolated from Different Body Parts (Ectosome and Choanosome) Envisaging the Development of Biomaterials

Chondrosia reniformis is a collagen-rich marine sponge that is considered a sustainable and viable option for producing an alternative to mammalian-origin collagens. However, there is a lack of knowledge regarding the properties of collagen isolated from different sponge parts, namely the outer region, or cortex, (ectosome) and the inner region (choanosome), and how it affects the development of biomaterials. In this study, a brief histological analysis focusing on C. reniformis collagen spatial distribution and a comprehensive comparative analysis between collagen isolated from ectosome and choanosome are presented. The isolated collagen characterization was based on isolation yield, Fourier-transformed infrared spectroscopy (FTIR), circular dichroism (CD), SDS-PAGE, dot blot, and amino acid composition, as well as their cytocompatibility envisaging the development of future biomedical applications. An isolation yield of approximately 20% was similar for both sponge parts, as well as the FTIR, CD, and SDS-PAGE profiles, which demonstrated that both isolated collagens presented a high purity degree and preserved their triple helix and fibrillar conformation. Ectosome collagen had a higher OHpro content and possessed collagen type I and IV, while the choanosome was predominately constituted by collagen type IV. In vitro cytotoxicity assays using the L929 fibroblast cell line displayed a significant cytotoxic effect of choanosome collagen at 2 mg/mL, while ectosome collagen enhanced cell metabolism and proliferation, thus indicating the latter as being more suitable for the development of biomaterials. This research represents a unique comparative study of C. reniformis body parts, serving as a support for further establishing this marine sponge as a promising alternative collagen source for the future development of biomedical applications.

The Effect of Rainbow Trout (Oncorhynchus mykiss) Collagen Incorporated with Exo-Polysaccharides Derived from Rhodotorula mucilaginosa sp. on Burn Healing

Burn is one of the physically debilitating injuries that can be potentially fatal; therefore, providing appropriate coverage in order to reduce possible mortality risk and accelerate wound healing is mandatory. In this study, collagen/exo-polysaccharide (Col/EPS 1-3%) scaffolds are synthesized from rainbow trout (Oncorhynchus mykiss) skins incorporated with Rhodotorula mucilaginosa sp. GUMS16, respectively, for promoting Grade 3 burn wound healing. Physicochemical characterizations and, consequently, biological properties of the Col/EPS scaffolds are tested. The results show that the presence of EPS does not affect the minimum porosity dimensions, while raising the EPS amount significantly reduces the maximum porosity dimensions. Thermogravimetric analysis (TGA), FTIR, and tensile property results confirm the successful incorporation of the EPS into Col scaffolds. Furthermore,the biological results show that the increasing EPS does not affect Col biodegradability and cell viability, and the use of Col/EPS 1% on rat models displays a faster healing rate. Finally, histopathological examination reveals that the Col/EPS 1% treatment accelerates wound healing, through greater re-epithelialization and dermal remodeling, more abundant fibroblast cells and Col accumulation. These findings suggest that Col/EPS 1% promotes dermal wound healing via antioxidant and anti-inflammatory activities, which can be a potential medical process in the treatment of burn wounds.

Terpenes extracted from marine sponges with antioxidant activity: a systematic review

Marine biodiversity has emerged as a very promising resource of bioactive compounds and secondary metabolites from different sea organisms. The sponge's secondary metabolites demonstrated various bioactivities and potential pharmacological properties. This systematic review of the literature focuses on the advances achieved in the antioxidant potential of marine sponges in vitro. The review was performed in accordance with PRISMA guidelines. The main inclusion criterion for analysis was articles with identification of compounds from terpene classes that demonstrate antioxidant activity in vitro. Searching in three different databases, two hundred articles were selected. After screening abstracts, titles and evaluating for eligibility of manuscripts 14 articles were included. The most performed analyzes to detect antioxidant activity were scavenging activity 2,2-diphenyl-1-picrylhydrazyl (DPPH) and measurement of intracellular reactive oxygen species (ROS). It was possible to identify 17 compounds of the terpene class with pronounced antioxidant activity in vitro. Scientific evidence of the studies included in this review was accessed by the GRADE analysis. Terpenes play an important ecological role, moreover these molecules have a pharmaceutical and industrial application.

Preparation of immobilized pepsin for extraction of collagen from bovine hide

In the extraction of collagens from mammalian tissues, the free pepsin used in the acid-pepsin extraction system is hard to recycle, and there is a risk of enzyme protein contamination in the extracted collagen products, which limits their applications. To solve this problem, an immobilized pepsin was successfully prepared via the covalent crosslinking of glutaraldehyde using a 3-aminopropyltriethoxysilane (APTES) surface modified silica clay as the support. The immobilized pepsin was applied for the extraction of collagen from bovine hide. The optimal immobilization process involves incubating pepsin with an initial concentration of 35 mg mL^-1 and glutaraldehyde with 5% activated APTES modified silica clay at 25 °C for 60 min, by which the loading amount of pepsin was 220 mg g^-1 and the activity of the immobilized pepsin was 4.2 U mg^-1. The collagen extracted using acetic acid and the immobilized pepsin method retained its complete triple helix structure. This research thus details an effective separation method using pepsin for extraction of collagen via an acetic acid-enzyme method, where the extracted collagen may be a candidate for use in biomaterial applications.