Bioactivity as an options value of sea cucumbers in the Egyptian Red Sea

Biomaterials and Bioactive Natural Products from Marine Invertebrates: From Basic Research to Innovative Applications

Aquatic invertebrates are a major source of biomaterials and bioactive natural products that can find applications as pharmaceutics, nutraceutics, cosmetics, antibiotics, antifouling products and biomaterials. Symbiotic microorganisms are often the real producers of many secondary metabolites initially isolated from marine invertebrates; however, a certain number of them are actually synthesized by the macro-organisms. In this review, we analysed the literature of the years 2010–2019 on natural products (bioactive molecules and biomaterials) from the main phyla of marine invertebrates explored so far, including sponges, cnidarians, molluscs, echinoderms and ascidians, and present relevant examples of natural products of interest to public and private stakeholders. We also describe omics tools that have been more relevant in identifying and understanding mechanisms and processes underlying the biosynthesis of secondary metabolites in marine invertebrates. Since there is increasing attention on finding new solutions for a sustainable large-scale supply of bioactive compounds, we propose that a possible improvement in the biodiscovery pipeline might also come from the study and utilization of aquatic invertebrate stem cells.

Marine-Derived Compounds with Potential Use as Cosmeceuticals and Nutricosmetics

The cosmetic industry is among the fastest growing industries in the last decade. As the beauty concepts have been revolutionized, many terms have been coined to accompany the innovation of this industry, since the beauty products are not just confined to those that are applied to protect and enhance the appearance of the human body. Consequently, the terms such as cosmeceuticals and nutricosmetics have emerged to give a notion of the health benefits of the products that create the beauty from inside to outside. In the past years, natural products-based cosmeceuticals have gained a huge amount of attention not only from researchers but also from the public due to the general belief that they are harmless. Notably, in recent years, the demand for cosmeceuticals from the marine resources has been exponentially on the rise due to their unique chemical and biological properties that are not found in terrestrial resources. Therefore, the present review addresses the importance of marine-derived compounds, stressing new chemical entities with cosmeceutical potential from the marine natural resources and their mechanisms of action by which these compounds exert on the body functions as well as their related health benefits. Marine environments are the most important reservoir of biodiversity that provide biologically active substances whose potential is still to be discovered for application as pharmaceuticals, nutraceuticals, and cosmeceuticals. Marine organisms are not only an important renewable source of valuable bulk compounds used in cosmetic industry such as agar and carrageenan, which are used as gelling and thickening agents to increase the viscosity of cosmetic formulations, but also of small molecules such as ectoine (to promote skin hydration), trichodin A (to prevent product alteration caused by microbial contamination), and mytiloxanthin (as a coloring agent). Marine-derived molecules can also function as active ingredients, being the main compounds that determine the function of cosmeceuticals such as anti-tyrosinase (kojic acid), antiacne (sargafuran), whitening (chrysophanol), UV protection (scytonemin, mycosporine-like amino acids (MAAs)), antioxidants, and anti-wrinkle (astaxanthin and PUFAs).

Black sea cucumber (Holothuria atra Jaeger, 1833) rescues Pseudomonas aeruginosa-infected Caenorhabditis elegans via reduction of pathogen virulence factors and enhancement of host immunity

A strategy to circumvent the problem of multidrug resistant pathogens is the discovery of anti-infectives targeting bacterial virulence or host immunity. Black sea cucumber (Holothuria atra) is a tropical sea cucumber species traditionally consumed as a remedy for many ailments. There is a paucity of knowledge on the anti-infective capacity of H. atra and the underlying mechanisms involved. The objective of this study is to utilize the Caenorhabditis elegans-P. aeruginosa infection model to elucidate the anti-infective properties of H. atra. A bioactive H. atra extract and subsequently its fraction were shown to have the capability of promoting the survival of C. elegans during a customarily lethal P. aeruginosa infection. The same entities also attenuate the production of elastase, protease, pyocyanin and biofilm in P. aeruginosa. The treatment of infected transgenic lys-7::GFP worms with this H. atra fraction restores the repressed expression of the defense enzyme lys-7, indicating an improved host immunity. QTOF-LCMS analysis revealed the presence of aspidospermatidine, an indole alkaloid, and inosine in this fraction. Collectively, our findings show that H. atra possesses anti-infective properties against P. aeruginosa infection, by inhibiting pathogen virulence and, eventually, reinstating host lys-7 expression.

Medicinal and health benefit effects of functional sea cucumbers

Sea cucumbers have long been used as food and traditional medicine in Asian countries with Stichopus hermanni, Thelenota ananas, Thelenota anax, Holothuria fuccogilva, and Actinopyga mauritiana as most highly-valued species. These organisms are potential source of high value-added compounds with therapeutic properties such as triterpene glycosides, carotenoids, bioactive peptides, vitamins, minerals, fatty acids, collagens, gelatins, chondroitin sulfates, amino acids. In the recent years, health benefit effects of sea cucumbers have been validated through scientific research and have shown medicinal value such as wound healing, neuroprotective, antitumor, anticoagulant, antimicrobial, and antioxidant. These functional materials lead to potential development in various foods and biomedicine industries. In this review, we have presented a general view of major medicinal and health benefit effects of functional sea cucumbers from Asia region. The structural significance and the potential application of sea cucumber-derived functional materials as well as their nutritional value are also discussed.

A novel structural fucosylated chondroitin sulfate from Holothuria Mexicana and its effects on growth factors binding and anticoagulation

Fucosylated chondroitin sulfate (FCS), a structurally distinct glycosaminoglycan from the body wall of sea cucumber, possesses many biological properties and pharmacology functions. The refined structure of FCS isolated from sea cucumber Holothuria Mexicana (FCS_hm) was characterized by NMR spectra and HILIC-FTMS, which demonstrated four types of branches in FCS_hm. Among these, two branches were α-L-Fuc-2S4S (where Fuc is fucose and S is sulfo) and α-L-Fuc-4S linked to O-3 of glucuronic acid residues, while others were identified as α-L-Fuc-4S and α-L-Fuc-3S4S attached to O-6 of N-acetylgalactosamine residue. Furthermore, the fucosyl branches were α-1,3-linked with different degree of polymerization from 1 to 5. FCS_hm exhibited high affinity to fibroblast growth factor 1 and 2, growth factors involved in neovascularization. Moreover, FCS_hm displayed intrinsic anticoagulant activity and inhibited thrombin and factor Xa activation by antithrombin III. Our results proposed a novel structural FCS and demonstrated its favorable application prospects in anti-angiogenesis and anticoagulation.

Cytotoxic Activity of Holothuria leucospilota Extract against Leishmania infantum In Vitro

Leishmaniasis is a tropical parasitic infection. The resistance and toxicity issues are the major complications and remain significant consequences related to the treatment of leishmaniasis with the recent and classical drugs. Thus there is an immediate requirement to develop new compounds for the treatment of this protozoan disease. Sea cucumbers or holothurians are potentially presented as the marine sources of antimicrobial and cytotoxic compounds. The aim of this study was investigation of in vitro antileishmanial activity of methanol extract of body wall, coelomic fluid, and cuvierian organs of Holothuria leucospilota obtained from coastal parts of Persian Gulf against Leishmania infantum promastigotes and axenic amastigotes. The colorimetric MTT assay was used to determine L. infantum promastigotes and axenic amastigotes viability at different concentrations of the extracts and drug control (Glucantime®) at time dependent manner and the results are represented as IC₅₀ (50% of inhibitory concentration). Coelomic fluid was the most active extract among the three different extracts of H. leucospilota against L. infantum promastigotes and axenic amastigotes with IC₅₀s of 62.33 μg/mL and 22.4 μg/mL and 73 μg/mL and 46 μg/mL at 48 and 72 hours after treatment, respectively. Cuvierian organs extract showed less toxicity with IC₅₀s more than 1000 μg/mL for both Leishmania infantum axenic amastigotes and promastigotes forms after 48 and 72 hours of exposure. Results acquired from the present study propose that the sea cucumber H. leucospilota may be a provoking source of antileishmanial compounds and could be a lead source in the development of the potent antileishmanial and cytotoxic drugs.

Sea Cucumbers Metabolites as Potent Anti-Cancer Agents

Sea cucumbers and their extracts have gained immense popularity and interest among researchers and nutritionists due to their nutritive value, potential health benefits, and use in the treatment of chronic inflammatory diseases. Many areas of the world use sea cucumbers in traditional foods and folk medicine. Though the actual components and their specific functions still remain to be investigated, most sea cucumber extracts are being studied for their anti-inflammatory functions, immunostimulatory properties, and for cancer prevention and treatment. There is large scope for the discovery of additional bioactive, valuable compounds from this natural source. Sea cucumber extracts contain unique components, such as modified triterpene glycosides, sulfated polysaccharides, glycosphingolipids, and esterified phospholipids. Frondanol A5, an isopropyl alcohol/water extract of the enzymatically hydrolyzed epithelia of the edible North Atlantic sea cucumber, Cucumaria frondosa, contains monosulfated triterpenoid glycoside Frondoside A, the disulfated glycoside Frondoside B, the trisulfated glycoside Frondoside C, 12-methyltetradecanoic acid, eicosapentaenoic acid, and fucosylated chondroitin sulfate. We have extensively studied the efficacy of this extract in preventing colon cancer in rodent models. In this review, we discuss the anti-inflammatory, immunostimulatory, and anti-tumor properties of sea cucumber extracts.

Asexual reproduction in holothurians

Aspects of asexual reproduction in holothurians are discussed. Holothurians are significant as fishery and aquaculture items and have high commercial value. The last review on holothurian asexual reproduction was published 18 years ago and included only 8 species. An analysis of the available literature shows that asexual reproduction has now been confirmed in 16 holothurian species. Five additional species are also most likely capable of fission. The recent discovery of new fissiparous holothurian species indicates that this reproduction mode is more widespread in Holothuroidea than previously believed. New data about the history of the discovery of asexual reproduction in holothurians, features of fission, and regeneration of anterior and posterior fragments are described here. Asexual reproduction is obviously controlled by the integrated systems of the organism, primarily the nervous system. Special molecular mechanisms appear to determine the location where fission occurs along the anterior-posterior axis of the body. Alteration of the connective tissue strength of the body wall may play an important role during fission of holothurians. The basic mechanism of fission is the interaction of matrix metalloproteinases, their inhibitors, and enzymes forming cross-link complexes between fibrils of collagen. The population dynamics of fissiparous holothurians are discussed.

Screening of microbial contamination and antimicrobial activity of sea cucumber Holothuria polii

Microbiological studies were carried out on microbial contamination and antimicrobial activity of sea cucumber Holothuria polii collected from Mediterranean Sea at Abu-kir shore of Alexandria, Egypt. The obtained results revealed the presence of isolates of five human Gram-negative pathogenic bacteria, representing five genera were identified to species level, including, Esherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella sp. and Shigella sp. In addition, an yeast Candida albicans was isolated. The pathogenic bacteria were identified using API 20E strip system (BioMereux). All collected H. polii specimens were healthy with no external signs of infection. Histopathological study of the tegument, intestine and gonads showed no abnormal changes. The antimicrobial activity of two tegumental ethanol extracts (A and B, differ in the method of dehydration) were tested against wide range of pathogenic bacteria and fungi, including intestinal, skin and nosocomial pathogens and one plant fungal pathogen. The results revealed a remarkable antifungal activity of the extract B at 2.5 mg/ml MIC90, especially on Aspergillus niger, Scloretium sp, C. albicans, Aspergillus flavus and Malassezia furfur, and limited antibacterial activity against Gram-negative bacteria ( Salmonella choleraesuis ATCC 14028 and Aeromonas hydrophila). The domain of bacterial and limited fungal contamination confirms the results that showed strong antifungal activity of investigated extract.

High-value components and bioactives from sea cucumbers for functional foods--a review

Sea cucumbers, belonging to the class Holothuroidea, are marine invertebrates, habitually found in the benthic areas and deep seas across the world. They have high commercial value coupled with increasing global production and trade. Sea cucumbers, informally named as bêche-de-mer, or gamat, have long been used for food and folk medicine in the communities of Asia and Middle East. Nutritionally, sea cucumbers have an impressive profile of valuable nutrients such as Vitamin A, Vitamin B1 (thiamine), Vitamin B2 (riboflavin), Vitamin B3 (niacin), and minerals, especially calcium, magnesium, iron and zinc. A number of unique biological and pharmacological activities including anti-angiogenic, anticancer, anticoagulant, anti-hypertension, anti-inflammatory, antimicrobial, antioxidant, antithrombotic, antitumor and wound healing have been ascribed to various species of sea cucumbers. Therapeutic properties and medicinal benefits of sea cucumbers can be linked to the presence of a wide array of bioactives especially triterpene glycosides (saponins), chondroitin sulfates, glycosaminoglycan (GAGs), sulfated polysaccharides, sterols (glycosides and sulfates), phenolics, cerberosides, lectins, peptides, glycoprotein, glycosphingolipids and essential fatty acids. This review is mainly designed to cover the high-value components and bioactives as well as the multiple biological and therapeutic properties of sea cucumbers with regard to exploring their potential uses for functional foods and nutraceuticals.

Antifungal activity of bivittoside-D from Bohadschia vitiensis (Semper)

This study was carried out to investigate the antifungal activity of Bohadschia vitiensis Semper whole body extracts, followed by isolation and characterisation of bioactive molecules. The methanol extract of the B. vitiensis showed promising activity in in vitro models against Candida albicans, Cryptococcus neoformans, Sporothrix schenckii, Trichophyton mentagrophytes, Aspergillus fumigatus and Candida parapsilosis. The antifungal activity was found in aqueous fraction against C. albicans, C. neoformans, S. schenckii, T. mentagrophytes and A. fumigatus. The major compound was purified from the aqueous fraction and was identified as bivittoside-D isolated earlier from the animal. It showed promising results against C. neoformans, C. neoformans, S. schenckii, T. mentagrophytes, A. fumigatus and C. parapsilosis.