Composition and In Vitro Antioxidant Effects of JellyfishCatostylus tagifrom Sado Estuary (SW Portugal)

Assessment of heavy metals and proximate composition in jellyfish (Lobonemoides robustus Stiasny, 1920) collected from Cox's Bazar coast: Human health risk assessment

Jellyfish are known for experiencing periodic blooms in population, which occur when their density increases suddenly. The present study assessed the level of heavy metals and proximate composition in the jellyfish Lobonemoides robustus collected from Cox's Bazar coast of Bangladesh. This is the first study conducted in Bangladesh. Most of the studied metals were not possible to detect in L. robustus samples because concentrations were below the detection limit. Ca, Na, Se, and Mg were found to have safe levels in the L. robustus while the amount of Pb was recorded 0.39 ppm. The findings of Target Hazard Quotient, and Carcinogenic Risk indicate that the L. robustus is safe for human consumption (both for children and adults). Hence, it is suitable for consumption and can be exported. This study emphasizes the need for regular marine environment monitoring to ensure that the seafood harvested from these waters is safe for consumption.

Jellyfishes—Significant Marine Resources with Potential in the Wound-Healing Process: A Review

The wound-healing process is a significant area of interest in the medical field, and it is influenced by both external and patient-specific factors. The aim of this review paper is to highlight the proven wound-healing potential of the biocompounds found in jellyfish (such as polysaccharide compounds, collagen, collagen peptides and amino acids). There are aspects of the wound-healing process that can benefit from polysaccharides (JSPs) and collagen-based materials, as these materials have been shown to limit exposure to bacteria and promote tissue regeneration. A second demonstrated benefit of jellyfish-derived biocompounds is their immunostimulatory effects on growth factors such as (TNF-α), (IFN-γ) and (TGF), which are involved in wound healing. A third benefit of collagens and polysaccharides (JSP) is their antioxidant action. Aspects related to chronic wound care are specifically addressed, and within this general theme, molecular pathways related to tissue regeneration are explored in depth. Only distinct varieties of jellyfish that are specifically enriched in the biocompounds involved in these pathways and live in European marine habitats are presented. The advantages of jellyfish collagens over mammalian collagens are highlighted by the fact that jellyfish collagens are not considered transmitters of diseases (spongiform encephalopathy) or various allergic reactions. Jellyfish collagen extracts stimulate an immune response in vivo without inducing allergic complications. More studies are needed to explore more varieties of jellyfish that can be exploited for their biocomponents, which may be useful in wound healing.

Jellyfish as Food: A Narrative Review

Studies toward a sustainable future conducted by international organizations uniformly agree about having to change some of our present consumer behaviors. Regarding food, suggestions include eating locally farmed, less industrialized and renewable food to promote health and circularity, and limiting waste. Jellyfish are frequently sorted and discarded after being caught with fish in fishing nets and gear. In contrast, we propose utilizing this by-catch as food. This review discusses the economic value and sustainability of jellyfish, the technologies used to prepare them for human consumption, their nutritional profile and health impacts and, finally, consumer acceptability and sensory evaluation of jellyfish food products. This discussion is critical for promoting jellyfish as an important aquatic resource to support blue and circular economies.

Jellyfish as an Alternative Source of Bioactive Antiproliferative Compounds

Jellyfish are commonly considered a nuisance for their negative effects on human activities (e.g., fisheries, power plants and tourism) and human health. However, jellyfish provide several benefits to humans and are commonly eaten in eastern countries. Additionally, recent studies have suggested that jellyfish may become a source of high-value molecules. In this study, we tested the effects of the methanolic extracts and enriched fractions, obtained by solid-phase extraction fractionation, from the scyphomedusae Pelagia noctiluca, Rhizostoma pulmo, Cotylorhiza tuberculata and the cubomedusa Caryddea marsupialis on different human cancer cell lines in order to evaluate a potential antiproliferative activity. Our results indicated that fraction C from Caryddea marsupialis-(CM) and C. tuberculata oral arms (CTOA) were the most active to reduce cell viability in a dose-dependent manner. LC/MS based dereplication analyses highlighted that both bioactive fractions contained mainly fatty acids and derivatives, with CM additionally containing small peptides (0.7–0.8 kDa), which might contribute to its higher biological activity. The mechanism of action behind the most active fraction was investigated using PCR arrays. Results showed that the fraction C of CM can reduce the expression of genes involved in apoptosis inhibition in melanoma-treated cells, which makes jellyfish a potential new source of antiproliferative drugs to be exploited in the future.

Jellyfish from Fisheries By-Catches as a Sustainable Source of High-Value Compounds with Biotechnological Applications

The world's population growth and consequent increased demand for food, energy and materials together with the decrease of some natural resources have highlighted the compelling need to use sustainably existing resources and find alternative sources to satisfy the needs of growing and longer-aging populations. In this review, we explore the potential use of a specific fisheries by-catch, jellyfish, as a sustainable source of high-value compounds. Jellyfish are often caught up with fish into fishing gear and nets, then sorted and discarded. Conversely, we suggest that this by-catch may be used to obtain food, nutraceutical products, collagen, toxins and fluorescent compounds to be used for biomedical applications and mucus for biomaterials. These applications are based on studies which indicate the feasibility of using jellyfish for biotechnology. Because jellyfish exhibit seasonal fluctuations in abundance, jellyfish by-catches likely follow the same pattern. Therefore, this resource may not be constantly available throughout the year, so the exploitation of the variable abundances needs to be optimized. Despite the lack of data about jellyfish by-catches, the high value of their compounds and their wide range of applications suggest that jellyfish by-catches are a resource which is discarded at present, but needs to be re-evaluated for exploitation within the context of a circular economy in the era of zero waste.

Adansonia digitata L. (Baobab Fruit) Effect on Postprandial Glycemia in Healthy Adults: A Randomized Controlled Trial

Baobab fruits have been traditionally used in Africa due to their therapeutic properties attributed to their high polyphenol content. The aim of the study was to investigate the effect of baobab fruit on postprandial glycaemia in healthy adults and to measure its bioactive compounds and antioxidant activity. The study (NCT05140629) was conducted on 31 healthy subjects. The participants were randomly allocated in the control group (oral glucose tolerance test (OGTT); n = 16) and in the intervention group (OGTT, followed by administration of 250 mL baobab aqueous extract (BAE); n = 15). Total phenols, proanthocyanins, hydrolyzable tannins, and antioxidant activity (FRAP, DPPH, ABTS, and inhibition of O2^•− and NO^• methods) were quantified. Repeated measures ANOVA of mixed type and independent samples t-test were used. Glycemia incremental area under the curve (p = 0.012) and glucose maximum concentration (p = 0.029) was significantly lower in the intervention group compared to the control group. The BAE revealed high total contents of phenols, proanthocyanins, and hydrolyzable tannins, as well as a strong capacity to scavenge superoxide anions and nitric oxide radicals and a high antioxidant activity. In conclusion, this study encourages the use of this food component as a promising source of natural antioxidants and a hypoglycemic agent under glucose load acute conditions.

Catostylus tagi (Class: Scyphozoa, Order: Discomedusae, Suborder: Rhizostomida, Family: Catostylidae) life cycle and first insight into its ecology

Jellyfish proliferations, which are conspicuous and natural events, cause blooms that may lead to severe consequences for anthropogenic activities and ecosystem structure and functioning. Although research during the last decade has focused on factors influencing the different jellyfish life stages, few species currently have their full life cycle known. In this context, we describe for the first time the developmental stages in the life cycle of Catostylus tagi, from planula to young medusa, reared in the laboratory. The species displays the typical Rhizostomida metagenetic life cycle. Mature scyphistomae display 16 tentacles and a total body length of 1.5 ± 0.2 mm. Only podocyst production and strobilation were observed. Strobilation, occurring continuously under laboratory conditions, was mainly polydisc. The eight-rayed typical ephyrae, with a total body diameter of 2.4 ± 0.4 mm at detachment, showed development typical of the Rhizostomida. As a first step in studying this species' ecology, we also present preliminary assessments of: (i) the influence of different temperature and salinity regimes on planulae survival, settlement and metamorphosis and (ii) the effect of temperature and diet on asexual reproduction. The results showed a high tolerance of planulae to a wide range of salinities (15‰ to 25‰), while polyp development was significantly faster at higher temperature (20-25 °C). Strobilation onset was 2-3 times faster at 20 °C (10.6 ± 5.4 to 15 ± 6.6 day at various tested diet) than at 15 °C (32.2 ± 3 day). Feeding was a key factor as unfed polyps never underwent strobilation during the trial. Finally, we present the spatial and seasonal distribution of C. tagi in the Tagus estuary (Portugal) in 2019, showing its occurrence throughout the year (except in April), with most observations recorded on the northern shoreline. As C. tagi shows the ability to form blooms and a wide tolerance for temperature and salinity (for planulae and medusae stage), it is essential to understand its life cycle.

Trace Metals Do Not Accumulate Over Time in The Edible Mediterranean Jellyfish Rhizostoma pulmo (Cnidaria, Scyphozoa) from Urban Coastal Waters

Jellyfish as food represent a millennial tradition in Asia. Recently, jellyfish have also been proposed as a valuable source of protein in Western countries. To identify health risks associated with the potential human consumption of jellyfish as food, trace element accumulation was assessed in the gonads and umbrella tissues of the Mediterranean Rhizostoma pulmo (Macri, 1778), sampled over a period of 16 months along the shallow coastal waters a short distance from the city of Taranto, an area affected by metallurgic and oil refinery sources of pollution. Higher tissue concentrations of trace elements were usually detected in gonads than in umbrella tissue. In particular, significant differences in the toxic metalloid As, and in the metals Mn, Mo, and Zn, were observed among different tissues. The concentrations of vanadium were slightly higher in umbrella tissues than in gonads. No positive correlation was observed between element concentration and jellyfish size, suggesting the lack of bioaccumulation processes. Moreover, toxic element concentrations in R. pulmo were found below the threshold levels for human consumption allowed by Australian, USA, and EU Food Regulations. These results corroborate the hypothesis that R. pulmo is a safe, potentially novel food source, even when jellyfish are harvested from coastal areas affected by anthropogenic impacts.

Biotechnological Applications of Scyphomedusae

As people across the world live longer, chronic illness and diminished well-being are becoming major global public health challenges. Marine biotechnology may help overcome some of these challenges by developing new products and know-how derived from marine organisms. While some products from marine organisms such as microalgae, sponges, and fish have already found biotechnological applications, jellyfish have received little attention as a potential source of bioactive compounds. Nevertheless, recent studies have highlighted that scyphomedusae (Cnidaria, Scyphozoa) synthesise at least three main categories of compounds that may find biotechnological applications: collagen, fatty acids and components of crude venom. We review what is known about these compounds in scyphomedusae and their current biotechnological applications, which falls mainly into four categories of products: nutraceuticals, cosmeceuticals, biomedicals, and biomaterials. By defining the state of the art of biotechnological applications in scyphomedusae, we intend to promote the use of these bioactive compounds to increase the health and well-being of future societies.

A Multi-screening Evaluation of the Nutritional and Nutraceutical Potential of the Mediterranean Jellyfish Pelagia noctiluca

The phylum Cnidaria is one of the most important contributors in providing abundance of bio- and chemodiversity. In this study, a comprehensive chemical investigation on the nutritional and nutraceutical properties of Mediterranean jellyfish Pelagia noctiluca was carried out. Also, compositional differences between male and female organisms, as well as between their main anatomical parts, namely bell and oral arms, were explored in an attempt to select the best potential sources of nutrients and/or nutraceuticals from jellyfish. With the exception of higher energy densities and total phenolic contents observed in females than males, no statistically significant differences related to the specimen's sex were highlighted for the other compound classes. Rather, the distribution of the investigated chemical classes varied depending on the jellyfish's body parts. In fact, crude proteins were more abundant in oral arms than bells; saturated fatty acids were more concentrated in bells than oral arms, whereas polyunsaturated fatty acids were distributed in the exact opposite way. On the other hand, major elements and trace elements demonstrated an opposite behavior, being the latter most accumulated in oral arms than bells. Additionally, important nutraceuticals, such as eicosapentaenoic and docosahexaenoic acids, and antioxidant minerals, were determined. Overall, obtained data suggest the potential employment of the Mediterranean P. noctiluca for the development of natural aquafeed and food supplements.

Eating jellyfish: safety, chemical and sensory properties

BACKGROUND

People's preference for fish with a high trophic level, like Atlantic cod and tuna, leads to a large food footprint. Responsible seafood consumption should include underutilised local products; hence the culinary use of edible jellyfish can be an effective contribution. The present work focused on Catostylus tagi to contribute to the consumption of edible jellyfish in the West.

RESULTS

A questionnaire conducted with 192 young people showed an interest in tasting jellyfish-based food (64.6%). The resulting product, obtained by an alternative cooking process to traditional Asian ones, was chemically characterised and underwent microbiological and heavy metals control. The results indicated its non-toxicity. Patients who were allergic to seafood as well as non-allergic volunteers revealed no allergic reaction to the jellyfish umbrella product (intakes up to 5 mg/kg body weight and 8 mg/kg, respectively). Seafood-trained panellists defined the product's main impact on the mouth as freshness (72 mg/kg body weight). The preliminary snack, a pâté, was positively accepted by allergic (7 in 9; n = 20) and non-allergic volunteers (6 in 7; n = 21).

CONCLUSION

The present study confirmed that jellyfish intake is safe, even for allergic individuals, and its organoleptic properties were accepted by the study population. © 2018 Society of Chemical Industry.

Determination of Aluminum in Edible Jellyfish Using Chrome Azurol S with Spot Test on Filter Paper

Aluminum (Al) has been well known as an environmental factor that may affect several enzymes and other biomolecules related to Alzheimer's disease. The increasing use of Al in the preparation and storage of food currently represents the main form of Al exposure for the general public. The present study was aimed to develop a household procedure for the rapid test determination of Al in edible jellyfish. The method was developed based on the reaction of Chrome Azurol S with Al in acidic medium, forming a colored compound on the surface of filter paper. Experimental design methodologies were used to optimize the measurement conditions. The proposed method was applied successfully to the analysis of Al in edible jellyfish products in clinical laboratory and household settings.

Catostylus tagi: partial rDNA sequencing and characterisation of nematocyte structures using two improvements in jellyfish sample preparation

BACKGROUND

More than 200 Scyphozoa species have been described, but few have been properly studied regarding their chemical and genetic characteristics. Catostylus tagi, an edible Scyphozoa and the sole European Catostylidae, occurs in summer at Tagus and Sado estuaries. Neither a systematic comparison between the two Catostylus communities nor a chemical approach on their nematocytes had been carried out yet.

METHODS

In order to achieve these purposes, optimisation of DNA extraction and of histochemical staining procedures were developed. Catostylus specimens from Tagus and Sado estuaries were compared by ribosomal 18S, 28S, and ITS1 partial sequencing. The morphochemistry of nematocytes was studied by optical and electronic microscopy.

RESULTS

Macroscopic and molecular results indicated that both communities belong to the same species, C. tagi. The hematoxylin and eosin staining allowed the visualisation of nematocyst genesis and indicated a basic character for the macromolecules on the shaft of euryteles and on the tubule of isorhizae and birhopaloids. By Masson's trichrome procedure, the basic properties of the tubules were confirmed and a collagenous profile for the toxins was suggested. Results of the alcian blue staining showed that the outer membrane of nematocyte may consist of macromolecules with acidic polysaccharides, consistent with NOWA and nematogalectin glycoproteins detected in Hydra, but also with poly-gamma-glutamate complex, chitin-like polysaccharides and hyaluronic acids. Through the von Kossa assays, calcium was detected; its position suggested interactions with polysaccharides of the membrane, with proteins of the contractile system or with both.

CONCLUSIONS

The optimisation of sample preparation for DNA extraction may facilitate further studies on little known jellyfish species. The improvement of the smear procedure simplified the use of stained reactions in zooplankton. Moreover, it was shown that good slide images might be acquired manually. The development of specific reactions, with traditional dyes and others, can give important contributions to clarify the chemical nature of the components of nematocytes. The characterisation of nematocyst toxins by staining tests is a goal to achieve.

Nutritional composition and total collagen content of three commercially important edible jellyfish

The study aimed to evaluate nutraceutical potential of three commercially significant edible jellyfish species (Acromitus hardenbergi, Rhopilema hispidum and Rhopilema esculentum). The bell and oral arms of these jellyfishes were analyzed for their proximate composition, calorific value, collagen content, amino acid profile, chemical score and elemental constituent. In general, all jellyfish possessed low calorific values (1.0-4.9 kcal/g D.W.) and negligible fat contents (0.4-1.8 g/100 g D.W.), while protein (20.0-53.9 g/100 g D.W.) and minerals (15.9-57.2g/100g D.W.) were found to be the richest components. Total collagen content of edible jellyfish varied from 122.64 to 693.92 mg/g D.W., accounting for approximately half its total protein content. The dominant amino acids in both bell and oral arms of all jellyfish studied includes glycine, glutamate, threonine, proline, aspartate and arginine, while the major elements were sodium, potassium, chlorine, magnesium, sulfur, zinc and silicon. Among the jellyfish, A. hardenbergi exhibited significantly higher total amino acids, chemical scores and collagen content (p<0.05) compared to R. hispidum and R. esculentum. Having good protein quality and low calories, edible jellyfish is an appealing source of nutritive ingredients for the development of oral formulations, nutricosmetics and functional food.

Effect of Cinnamon Tea on Postprandial Glucose Concentration

Glycaemic control, in particular at postprandial period, has a key role in prevention of different diseases, including diabetes and cardiovascular events. Previous studies suggest that postprandial high blood glucose levels (BGL) can lead to an oxidative stress status, which is associated with metabolic alterations. Cinnamon powder has demonstrated a beneficial effect on postprandial glucose homeostasis in animals and human models. The purpose of this study is to investigate the effect of cinnamon tea (C. burmannii) on postprandial capillary blood glucose level on nondiabetic adults. Participants were given oral glucose tolerance test either with or without cinnamon tea in a randomized clinical trial. The data revealed that cinnamon tea administration slightly decreased postprandial BGL. Cinnamon tea ingestion also results in a significantly lower postprandial maximum glucose concentration and variation of maximum glucose concentration (p < 0.05). Chemical analysis showed that cinnamon tea has a high antioxidant capacity, which may be due to its polyphenol content. The present study provides evidence that cinnamon tea, obtained from C. burmannii, could be beneficial for controlling glucose metabolism in nondiabetic adults during postprandial period.