Search Results (14)

The seasonal occurrence of the Black Sea jellyfish Blackfordia virginica Mayer, 1910 blooms is a reason of concern in the Guadiana estuary in the South of Portugal (South-West Europe), causing considerable economic and ecological impacts to fisheries. Due to jellyfish biochemical properties, they may represent an opportunity as an alternative food source for humans. In this context, this work evaluated the nutritional profile of B. virginica (proximate composition, amino acids, minerals, and fatty acids methyl ester content). Blackfordia virginica biomass may be adequate for human consumption, as it has nutritional properties resembling other edible jellyfish species, with relevant levels of minerals, moderate content in crude protein, low-fat content, and a low energetic value. The high Cd levels in the biomass of B. virginica from the Guadiana Estuary may compromise its safety as a food source. Moreover, if these jellyfishes are proven as an edible invasive species, their management through fisheries should evaluate the cost effectiveness of investments. Full article

This study aimed to develop bioactive protein hydrolysates from low-value edible jellyfish obtained from local fisheries using enzymatic hydrolysis. Fresh white jellyfish were hydrolyzed using several commercial proteases, including alcalase (WJH-Al), flavourzyme (WJH-Fl), and papain (WJH-Pa). The antioxidant, immunomodulatory, and anticancer activities of these white jellyfish hydrolysates (WJH) were investigated. The results demonstrated that the crude WJH exhibited strong antioxidant properties, including DPPH, ABTS, and hydroxyl radical scavenging activities, as well as ferric-reducing antioxidant power. Additionally, the hydrolysates showed notable immunomodulatory activity. However, all WJH samples displayed relatively low ability to inhibit HepG2 cell proliferation at the tested concentrations. Among the hydrolysates, WJH-Pa demonstrated the highest antioxidant and immunomodulatory activities and was therefore selected for further bioactive peptide isolation and characterization. Ultrafiltration membranes with three molecular weight (MW) cut-offs (1, 3, 10 kDa) were used for peptide fractionation from WJH-Pa. Six potential peptides were identified with the MW range of 1049–1292 Da, comprising 9–12 residues, which exhibited strong antioxidant and immunomodulatory activities. Full article

This study describes the set-up and optimization of a fermentation strategy applied to a composite raw material containing jellyfish biomass as the principal ingredient. New fermented food was developed by combining fresh jellyfish Rhizostoma pulmo and the sequential solid-state submerged liquid fermentation method used in Asian countries for processing a high-salt-containing raw material. Aspergillus oryzae was used to drive the first fermentation, conducted in solid-state conditions, of a jellyfish-based product, here named Jelly paste. The second fermentation was performed by inoculating the Jelly paste with different selected bacteria and yeasts, leading to a final product named fermented Jellyfish paste. For the first time, a set of safety parameters necessary for monitoring and describing a jellyfish-based fermented food was established. The new fermented products obtained by the use of Debaryomyces hansenii BC T3-23 yeast strain and the Bacillus amyloliquefaciens MS3 bacterial strain revealed desirable nutritional traits in terms of protein, lipids and total phenolic content, as well as valuable total antioxidant activity. The obtained final products also showed a complex enzyme profile rich in amylase, protease and lipase activities, thus making them characterized by unique composite sensory odor descriptors (umami, smoked, dried fruit, spices). Full article

In recent years, the jellyfish (JF) blooms in many coastal areas around the world, due to climate change, have pointed toward its possible exploitation as an alternative seafood product to support the global fishery sector. However, being a novel food in Western countries, there is a gap in knowledge on JF sensory properties. This research aims to develop a sensory lexicon for edible JF through a fast but reliable method, such as RATA. Sensory attributes collected from the literature were selected through RATA applied to five mildly processed JF. The lexicon selected was then validated on three JF samples, through descriptive analysis, to test its applicability and discrimination power. The results showed that RATA could be a reliable tool in the lexicon development of novel foods, such as JF. Moreover, the lexicon developed provides a valuable communication instrument, which will open new sensory research studies focusing on JF palatability. Full article

Edible jellyfish are a traditional Southeast Asian food, usually prepared as a rehydrated product using a salt and alum mixture, whereas they are uncommon in Western Countries and considered as a novel food in Europe. Here, a recently developed, new approach for jellyfish processing and stabilization with calcium salt brining was upgraded by modifying the pre-treatment step of freshly caught jellyfish and successfully applied to several edible species. Treated jellyfish obtained by the application of the optimized version of this method respected both quality and safety parameters set by EU law, including no pathogenic microorganisms, absence or negligible levels of histamine and of total volatile basic nitrogen, no heavy metals; and the total bacterial, yeast, and mold counts were either negligible or undetectable. Jellyfish treated by the presented method exhibited unique protein content, amino acid and fatty acid profiles, antioxidant activity, and texture. The optimized method, initially set up on Rhiszostoma pulmo, was also successfully applied to other edible jellyfish species (such as Cotylorhiza tuberculata, Phyllorhiza punctata, and Rhopilema nomadica) present in the Mediterranean Sea. This study discloses an innovative process for the preparation of jellyfish-based food products for potential future distribution in Europe. Full article

As one of the edible jellyfish species, Rhopilema esculentum (Kishinouye, 1891) is a traditional fishery resource and an important economic aquaculture species in China. However, facing the current situation of natural resources exhaustion and problems of breeding population frequent disease, quantity, and quality of seedlings in artificial breeding cannot satisfy the market demand. Temperature and salinity have been considered to play crucial roles in regulating R. esculentum asexual reproduction. This study examined the combined effects by exposing post-preserved R. esculentum podocysts (preserved at 2 ± 1 °C for more than 12 months) to three variable temperatures (simulated temperatures increasing from different starting dates of 14.5 °C on 1 April, 18 °C on 1 May, and 23.2 °C on 1 July, respective to natural levels) and three salinities (20, 25, and 30). Podocyst excystment, the start time of strobilation, duration of strobilation, and cumulative ephyra numbers were tested for 45 days and transfer rates from podocysts to ephyrae were analyzed to assess the most optimal combination of temperature and salinity. The results showed that podocyst excystment and ephyrae production occurred in all treatments. Higher temperature and lower salinity significantly facilitated the podocyst excystment and accelerated the start time of strobilation (p < 0.05). Significantly greater ephyra numbers were produced with lower salinity (20 and 25) and temperatures increasing from 18 °C on 1 May to natural levels (p < 0.05). There were significant interactions between temperature and salinity on the cumulative ephyra numbers and transfer rates from podocysts to ephyrae (p < 0.05). These results suggested that R. esculentum podocysts for long-term preservation at low temperature could be recycled. Temperature and salinity regulation can affect the number and time of R. esculentum seedlings to achieve high production and satisfy the market demand for real-time seedling supply. This conclusion would provide a scientific basis for the innovative methods of sustainable utilization of the edible jellyfish (R. esculentum) resources. Full article

The edible jellyfish Acromitus hardenbergi Stiasny, 1934 is harvested throughout the year at the mouth of the Perak River, Malaysia. Although this species is an important fishery resource in the local area, limited biological studies have been carried out on it. The aim of the present study was to elucidate the life cycle of this unique brackish-water jellyfish in order to conserve the species and develop sustainable jellyfish fisheries. Mature medusae were collected at the mouth of the Perak River. Embryonic and larval development after fertilization was completed within 24 h until the planula stage and within 48 h until the polyp stage. Primary polyps had a long stalk with a small stolon at the base of the calyx. Fully developed polyps were bowl-or goblet-shaped but became an elongated stalk under starved conditions. Asexual reproduction was accomplished only by means of budding, and no podocysts were produced. Strobilation was mono-disc type. These characteristics may be adaptations to the dynamic environmental conditions in the estuary of the Perak River, where salinity fluctuates widely due to strong inflows of highly turbid freshwater coupled with tidal changes. This study suggests that polyps of A. hardenbergi expand their population not by podocysts, but by budding as quickly as possible and forming one large ephyra by mono-disc strobilation without the residuum, because the polyp cannot remain for a long time at its settlement place in the sediment-rich environment with drastic salinity change. Full article

Exploitation of the cannonball jellyfish (Stomolophus sp. 2) is increasing in Mexico and USA due to successful fisheries associated with seasonal blooms in coastal areas. Previously, it was proposed that such blooms could be identified by recognizing the presence of young stages in the water. In our work, we aim to describe the young stages (ephyra and metaephyra) found in the Las Guásimas lagoon, Sonora, Mexico. The description of specimens is based on photographs, drawings, and morphological measurements aimed at helping in the early detection of blooming events. Full article

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. Full article

Venomics, the study of biological venoms, could potentially provide a new source of therapeutic compounds, yet information on the venoms from marine organisms, including cnidarians (sea anemones, corals, and jellyfish), is limited. This study identified the putative toxins of two species of jellyfish—edible jellyfish Rhopilema esculentum Kishinouye, 1891, also known as flame jellyfish, and Amuska jellyfish Sanderia malayensis Goette, 1886. Utilizing nano-flow liquid chromatography tandem mass spectrometry (nLC–MS/MS), 3000 proteins were identified from the nematocysts in each of the above two jellyfish species. Forty and fifty-one putative toxins were identified in R. esculentum and S. malayensis, respectively, which were further classified into eight toxin families according to their predicted functions. Amongst the identified putative toxins, hemostasis-impairing toxins and proteases were found to be the most dominant members (>60%). The present study demonstrates the first proteomes of nematocysts from two jellyfish species with economic and environmental importance, and expands the foundation and understanding of cnidarian toxins. Full article

Edible jellyfish are mainly consumed and marketed in Southeastern Countries, generally produced by a multi-phase drying process, using mixtures of salt and alum. Recently, jellyfish have become very attractive also for Western food markets. They are novel food in Europe and no recognized handling/processing steps have been set up yet. Moreover, no specific food safety and quality parameters are available. In this study, we identified a set of safety and quality parameters for jellyfish, based on standards and process hygiene criteria used in Europe for other products. These assays were tested on three different jellyfish preparations that can be used as raw materials for subsequent food processing. All jellyfish samples revealed the absence of pathogens (Salmonella spp. and Listeria monocytogenes), Enterobacteriaceae and Pseudomonas spp., even if a limited presence of Staphylococci was observed. No biogenic amine histamine was detected and negligible levels of total volatile basic nitrogen (TVB-N) were revealed. Total bacterium, yeast and mold counts were negligible or undetectable by conventional accredited methods, and conversely the results were higher when optimized saline conditions were used. This study, for the first time, established a set of quality and safety parameters necessary for first-operations and subsequent processing of jellyfish as novel food. Highlights: Jellyfish can represent a novel food in Europe. Identification of safety and quality parameters for jellyfish food products. Saline conditions are essential for improving safety and quality assessment of jellyfish as food. Full article

There are more than 200,000 marine species worldwide. These include many important economic species, such as large yellow croaker, ribbonfish, tuna, and salmon, but also many potentially toxic species, such as blue-green algae, diatoms, cnidarians, ctenophores, Nassarius spp., and pufferfish. However, some edible and toxic species may look similar, and the correct identification of marine species is thus a major issue. The failure of traditional classification methods in certain species has promoted the use of DNA barcoding, which uses short, standard DNA fragments to assist with species identification. In this review, we summarize recent advances in DNA barcoding of toxic marine species such as jellyfish and pufferfish, using genes including cytochrome oxidase I gene (COI), cytochrome b gene (cytb), 16S rDNA, internal transcribed spacer (ITS), and Ribulose-1,5-bisphosphate carboxylase oxygenase gene (rbcL). We also discuss the application of this technique for improving the identification of marine species. The use of DNA barcoding can benefit the studies of biological diversity, biogeography, food safety, and the detection of both invasive and new species. However, the technique has limitations, particularly for the analysis of complex objects and the selection of standard DNA barcodes. The development of high-throughput methods may offer solutions to some of these issues. Full article

Marine invertebrates, such as oysters, mussels, clams, scallop, jellyfishes, squids, prawns, sea cucumbers and sea squirts, are consumed as foods. These edible marine invertebrates are sources of potent bioactive peptides. The last two decades have seen a surge of interest in the discovery of antioxidant peptides from edible marine invertebrates. Enzymatic hydrolysis is an efficient strategy commonly used for releasing antioxidant peptides from food proteins. A growing number of antioxidant peptide sequences have been identified from the enzymatic hydrolysates of edible marine invertebrates. Antioxidant peptides have potential applications in food, pharmaceuticals and cosmetics. In this review, we first give a brief overview of the current state of progress of antioxidant peptide research, with special attention to marine antioxidant peptides. We then focus on 22 investigations which identified 32 antioxidant peptides from enzymatic hydrolysates of edible marine invertebrates. Strategies adopted by various research groups in the purification and identification of the antioxidant peptides will be summarized. Structural characteristic of the peptide sequences in relation to their antioxidant activities will be reviewed. Potential applications of the peptide sequences and future research prospects will also be discussed. Full article

Jellyfish are recorded with increasing frequency and magnitude in many coastal areas and several species display biological features comparable to the most popular Asiatic edible jellyfish. The biochemical and antioxidant properties of wild gelatinous biomasses, in terms of nutritional and nutraceutical values, are still largely unexplored. In this paper, three of the most abundant and commonly recorded jellyfish species (Aurelia sp.1, Cotylorhiza tuberculata and Rhizostoma pulmo) in the Mediterranean Sea were subject to investigation. A sequential enzymatic hydrolysis of jellyfish proteins was set up by pepsin and collagenase treatments of jellyfish samples after aqueous or hydroalcoholic protein extraction. The content and composition of proteins, amino acids, phenolics, and fatty acids of the three species were recorded and compared. Protein content (mainly represented by collagen) up to 40% of jellyfish dry weight were found in two of the three jellyfish species (C. tuberculata and R. pulmo), whereas the presence of ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) was significantly higher in the zooxanthellate jellyfish C. tuberculata only. Remarkable antioxidant ability was also recorded from both proteinaceous and non proteinaceous extracts and the hydrolyzed protein fractions in all the three species. The abundance of collagen, peptides and other bioactive molecules make these Mediterranean gelatinous biomasses a largely untapped source of natural compounds of nutraceutical, cosmeceutical and pharmacological interest. Full article