Sea Cucumber Research Articles

Dietary tryptophan decreases the impacts of seawater temperature changes on behavior and gut health of the sea cucumber Apostichopus japonicus

Seawater temperature change is an important concern for seed production and pond culture of sea cucumbers. The present study found that tentacle activity frequency was significantly lower in sea cucumbers exposed to continuous and rapid temperature increases than that of those at ambient temperature. Feeding behavior directly determines food intake, and further affects physiology and growth efficiency of sea cucumbers. This means that the decline in feeding caused by continuous and rapid temperature increases needs to be addressed in sea cucumber aquaculture. However, a sudden temperature change of 5 °C had no significant effect on behaviors of sea cucumbers. This indicates that continuous temperature increases, rather than a sudden increase, result in behavioral impacts on sea cucumbers. Therefore, we recommend aqua-farmers reduce the feeding amount for sea cucumbers during continuous and rapid temperature increases.In the present study, feeding behavior was significantly higher in sea cucumbers fed with 3% dietary tryptophan than that of those fed with 0% and 5% dietary tryptophan. This indicates that 3% dietary tryptophan increases the food intake of sea cucumbers, and mitigates the feeding decline caused by continuous and rapid temperature increase. This indicates that tryptophan has the potential to promote the feeding of sea cucumbers in seed production and pond culture. Adhesion capacity of sea cucumbers fed with 5% dietary tryptophan was significantly higher than that of individuals fed with 0% and 3% dietary tryptophan. This suggests that dietary tryptophan increases the feeding of sea cucumbers exposed to continuous and rapid temperature increases in pond culture and seed production. In addition, this study found that sea cucumbers fed with 3% dietary tryptophan had higher intestinal colony richness under the continuously rapid temperature change. The present study provides an effective method to improve adhesion behavior and to alleviate the impacts on feeding behavior for seed production and pond culture of sea cucumbers exposed to continuous and rapid temperature increases.

Patterns of the Nutrients and Metabolites in Apostichopus japonicus Fermented by Bacillus natto and Their Ability to Alleviate Acute Alcohol Intoxication.

The aim of this study was to understand the changes in nutrient composition and differences in metabolites in Apostichopus japonicus fermented by Bacillus natto and their function in alleviating acute alcohol intoxication (AAI) through in vivo studies. The results showed no significant difference between the basic components of sea cucumber (SC) and fermented sea cucumber (FSC). The SC proteins were degraded after fermentation, and the amino acid content in FSC was significantly increased. The differentially abundant metabolites of SC and FSC were identified by LC-MS/MS. The contents of amino acid metabolites increased after fermentation, and arachidonic acid metabolism was promoted. The results demonstrated that FSC alleviated AAI by improving the activities of alcohol-metabolizing enzymes and antioxidant enzymes in the liver but did not alleviate the accumulation of triglycerides. Our results will provide beneficial information for the development and application of new products from FSC.

Modelling the habitat preferences of the NE-Atlantic Sea cucumber Holothuria forskali: Demographics and abundance

Sea cucumbers' historical demand, together with the depletion of several traditional species in the market, has popularized new target species from new fishing grounds. Holothuria forskali is one of those emergent species in the trade market. However, it is a species for which there is no relevant information to allow sustainable stock management. Fundamental knowledge of the populations' structure and habitat preferences are key elements without which any measure is inconsequent. This work aims to fill that gap by modelling temporal and spatial patterns of abundance and demographic structure of this species in a NE-Atlantic area, as a function of environmental features.For a period of 15 months, nine regular sampling campaigns collected data on density, individual length, individual conditions of occurrence (e.g. sheltered, on sand, on algae cover) and environmental parameters (water column, sediment, substrate cover and type), using random transects throughout a costal rocky-reef, considering habitat heterogeneity and substrate types. To determine the species' habitat preferences Generalized Linear Models were used to model density and demographic structure of the species as a function of environmental conditions. The models revealed that the main drivers shaping the distribution of H. forskali are neither abiotic nor biotic parameters of the water column, but physical stressors, like current intensity and depth, and substrate type in a patchy distribution pattern. Estuarine conditions are generally avoided, although with a size-dependent opportunistic strategy. Larger individuals show temporal and spatial displacement patterns towards suitable reproductive conditions (pre-breeding aggregation) and favourable feeding grounds and smaller size-classes tend to aggregate in higher numbers in more stable environments.Sustainable sources for market supply, like aquaculture, are still a long way from commercial production. So, these results are fundamental to support effective conservation measures for stock management of H. forskali.

Dietary steroids promote body weight growth and induce gametogenesis by increasing the expressions of genes related to cell proliferation of sea cucumber (Apostichopus japonicus)

Steroids play a vital role in animal survival, promoting growth and development when administered appropriate concentration exogenously. However, it remains unclear whether steroids can induce gonadal development and the underlying mechanism. This study assessed sea cucumber weights post-culturing, employing paraffin sections and RNA sequencing (RNA-seq) to explore gonadal changes and gene expression in response to exogenous steroid addition. Testosterone and cholesterol, dissolved in absolute ethanol, were incorporated into sea cucumber diets. After 30 days, testosterone and cholesterol significantly increased sea cucumber weights, with the total weight of experimental groups surpassing the control. The testosterone-fed group exhibited significantly higher eviscerated weight than the control group. In addition, dietary steroids influenced gonad morphology and upregulated genes related to cell proliferation，such as RPL35, PC, eLF-1, MPC2, ADCY10 and CYP2C18. Thees upregulated differentially expressed genes were significantly enriched in the organic system, metabolism, genetic information and environmental information categories. These findings imply that steroids may contribute to the growth and the process of genetic information translation and protein synthesis essential for gonadal development and gametogenesis.

Seasonal and taxa impact on edible sea cucumber's metabolome and in relation to its cytotoxicity as analyzed via UHPLC/HR‐MS/MS‐based molecular networking and chemometrics

AbstractSea cucumbers, belonging to class Holothuroidea, are marine invertebrates with substantial bioactive compounds. This study provides the first comparative metabolome profiling of Holothuria atra and Actinopyga crassa sea cucumbers in relation to their season of collection to dissect between winter and summer samples, providing several first‐time reported metabolites as well as the effect of metabolome variation on their cytotoxic activity against colon and prostate cancer cell lines. Ultrahigh‐performance liquid chromatography coupled with high‐resolution mass spectrometry and global natural products social molecular networking followed by multivariate data analysis were employed for metabolite profiling and seasonal biomarker assignment for each species. The cytotoxic activity was evaluated using in vitro assays against prostate and colon cancer cell lines. A total of 113 metabolites were annotated in both species, including 4 organic acids, 21 sulfoquinovosyl glycerol (sulfolipids), 5 alkyl sulfates, 13 sulfated/saponins, 8 sulfated/triterpene mono/di‐glycosides, 10 triterpenes, 13 sulfated/sterols, 32 phospholipids, 4 sphingolipids, and 3 glycerolipids, several of which are new or first‐time reported. Multivariate data analyses revealed lipid accumulation in summer samples versus triterpene and saponin enrichment in winter‐collected samples, particularly in H. atra, rationalizing its potent cytotoxic activity (IC50 6–12 µg/mL) as revealed using a regression model. However, winter‐collected samples of A. crassa are relatively the least abundant in antinutrient saponins, thus considered to have higher food value.

Correlation between Coral Reef Cover Condition and the Abundance of Megabenthos on Setan Island, West Sumatra

In the coral reef ecosystem, there is a food source for small fish, which are prey for various kinds of associated biota; one of the biota that lives in the coral reef ecosystem is megabenthos. Megabenthos is influenced by the quality of the coral reef ecosystem, where if conditions are good, the coral will have a greater chance of high megabenthos diversity. This research was carried out in March 2023 in Setan Island, West Sumatra. This research analyzes the relationship between coral reef conditions and megabenthos abundance. The method used in this research is a survey method. Observations of coral reef cover were carried out using the Underwater Photo Transect (UPT) method, and megabenthos abundance was measured using the Bhentos Belt Transect (BBT) method. Observations were carried out at four stations (3 and 6 m deep) with a transect length of 50 m. Based on the average value of the percentage of coral reef cover, it is still categorized as being in poor condition, namely 18.87%. There is a relationship between the percentage of live coral reef cover and the abundance of megabenthos with a percentage of 55.27%, with the types of megabenthos clams (Tridacna sp), sea cucumbers (Holothuria sp), snails (Trochus sp), lobsters (Panulirus sp), fur pigs (Diadema sp), snails (Drupella sp), and starfish (Acanthasper sp).

Troubling the Waters: Gendered Dispossession, Violence, and Sea Cucumber Aquaculture in Madagascar

Poverty reduction and fisheries management in Madagascar have converged on the marine seascape, directed at an unassuming creature: the sea cucumber. In southwestern Madagascar, the enclosure of what was once a common pool resource has led to violence and new gendered seascapes. This form of blue grabbing, promoted by private companies and NGOs alike as an avenue to achieve conservation and develop coastal economies, has fundamentally restructured property relations and who benefits from marine resources. Sea cucumber pens, established in some areas with the input of a narrow local elite and guarded at times by the police have become high risk environments where fishers report injury and death, pointing to important questions about the metrics and means of sustainable production in the marine realm, and whose interests and access to marine resources are prioritized.

Determination of teicoplanin and ramoplanin residues in aquaculture products by a modified QuEChERS method combined with UPLC-MS/MS

A QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method was developed to provide good analytical results for teicoplanin (TEC) and ramoplanin (RAM) residues in aquaticproducts. The analytes was extraction from aquatic product samples using chitosan in the QuEChERS procedure. Compared to conventional adsorbents, chitosan has a relatively good purification ability for the targets.The matrix effects of aquatic products, such as crucian carp, carp, silver carp, tilapia, mandarin fish, turbot, shrimp, sea cucumber and so on, were evaluated by high performance liquid chromatography coupled to triple-quadrupole tandem mass spectrometry. Throughout the validation experiments, the limits of detections and quantifications ranged from 0.4 ∼ 0.8 μg kg−1 and 1.0 ∼ 3.0 μg kg−1, respectively. Calibration curves showed correlation coefficient values higher than 0.998 in range between 1 and 100 μg kg−1. The recoveries ranged from 89.8 % to 110.0 % with relative standard deviation less than 7.2 % in nine typical aquaticproducts. The method shows low matrix effect (-18.5 %∼-2.6 %) for all targets in different aquaticproducts. The proposed methods proved to be reliable, effective and enables rapid determination of large batch samples, indicating its good applicability for detection and monitoring of TEC and RAM residues in aquaticproducts.

Marine zoobenthos recognition algorithm based on improved lightweight YOLOv5

Detecting the distribution and density of marine zoobenthos is crucial for monitoring healthy coastal ecosystems and for growth reference tracking in precision aquaculture. However, current detection algorithms for marine zoobenthos have high computational complexity and cannot guarantee a balance between accuracy and speed, limiting their deployment in fishery equipment. This study used a portion of the Augmented Underwater Detection Dataset, a large underwater biological dataset containing marine zoobenthos data. A marine zoobenthos recognition algorithm was proposed for sea cucumbers, sea urchins, and scallops based on an improved lightweight YOLOv5, which can recognize the three types of marine zoobenthos. In the image enhancement module, an underwater image enhancement algorithm based on color balance and multi-input fusion is used, which turns the blurred image into a natural appearance of the seabed image. The lightweight backbone network EfficientnetV2-S was chosen to replace the original YOLOv5 backbone network, reducing network parameter calculations and improving recognition speed. A Bottleneck Transformer was introduced into the backbone network, and an attention mechanism based on the convolution module was introduced to construct the embedded Convolutional Block Attention Module in the Neck structure of YOLOv5, thereby improving the recognition accuracy of the lightweight YOLOv5 model. The experimental results showed that the mAP of the proposed algorithm reached 0.941, which is an improvement of 0.002 compared with the original YOLOv5l algorithm. The computation of this algorithm is 37.0 FLOPs (G), the model size is 54 MB, and the inference time is 5.9 ms. Compared to the original YOLOv5l algorithm, the reductions are 66.1%, 40.5%, and 39.2%. The proposed algorithm efficiently identified and classified marine zoobenthos.

Eukaryotic food sources analysis of two tropical sea cucumber species under different seasons providing insights into provender selection

As the typical deposit-feeding organism, in the process of aquaculture, adult sea cucumbers usually feed on bioclasts in sediments under the artificial environment. Understanding feeding preference is one of the most essential parts for providing guidance for sea cucumber aquaculture. However, up to now, there have been few studies on the exact ingredients of these natural foods for holothurians, especially for tropical sea cucumbers. In present study, the eukaryotic composition of gut contents of two tropical sea cucumber species under enclosed waters of ponds, Stichopus monotuberculatus and Holothuria scabra, were investigated and compared with each other by high-throughput DNA sequencing. We also analyzed the variability of intestinal eukaryotic composition of the two sea cucumbers in different seasons (dry / wet seasons). The sequences of 18 S rRNA gene V4 region were amplified and a total of 2234 operational taxonomic units (OTUs) were obtained. S. monotuberculatus and H. scabra in dry season both fed mainly on Chlorophyta and Diatomea. In wet season, S. monotuberculatus fed mainly on Arthropoda and Diatomea, and H. scabra had a superior Ascomycota and Arthropoda concentrations. We found there were significant differences in eukaryotic composition of the same species between the wet season and dry season, and seasonal differences were higher than differences between species. Several eukaryotic organisms such as copepods Pseudodiaptomus nihonkaiensis were identified, whose related species as superior biological feed organisms have been successfully applied in aquaculture. These organisms may be considered as an additive feed for captive breeding of S. monotuberculatus. This study provides insights into provender selection for tropical sea cucumbers aquaculture.

Potentially toxic element assessment and biological accumulation in two sea cucumbers species Holothuria poli and Holothuria tubulosa

Knowledge of Potentially Toxic Elements (PTEs) and tissue accumulation profiles of holothurians is limited, especially in Greek seas, so there is no complete picture of their role as bioindicators. This will result in an understanding of their ecology and by extension, their contribution to the marine ecosystem. In this particular study, a total of 7 elements (As, Cd, Cr, Cu, Mn, Pb, and Zn) were analyzed from the edible muscle tissue and gut contents of two species of sea cucumbers, Holothuria poli and Holothuria tubulosa, as well as surface sediment samples in the marine area of Pagasitikos Gulf. According to the results presented, H. tubulosa for the majority of PTEs had significantly higher values than H. poli in the edible muscle tissue, while in the gut content, H. poli had the highest values. The Biota Sediment Accumulation Factor (BSAF) was calculated to determine the elemental uptake of sea cucumbers. As Cd and Mn showed the highest BSAF values in both species. In addition, the sediment results were compared to sediment quality guidelines, and it was found that Cr exceeded the Medium Impact Range (ERM) values in 80% of the samples, while other elements were found between the Low Impact Range (ERL) and ERM values. The aim of the study was to present the increasing accumulation of elements in the tissues of sea cucumbers so that they represent a significant challenge for their commercial and economic use.

Development of Antibacterial Peptides with Membrane Disruption and Folate Pathway Inhibitory Activities against Methicillin-Resistant Staphylococcus aureus.

Antimicrobial peptides (AMPs) offer an opportunity to overcome multidrug resistance. Here, novel peptides were designed based on AMP fragments derived from sea cucumber hemolytic lectin to enhance anti-methicillin-resistant Staphylococcus aureus (MRSA) activity with less side effects. Two designed peptides, CGS19 (LARVARRVIRFIRRAW-NH2) and CGS20 (RRRLARRLIFFIRRAW-NH2), exhibited strong antibacterial activities against clinically isolated MRSA with MICs of 3-6 μM, but no obvious cytotoxicity was observed. Consistently, CGS19 and CGS20 exerted rapid bactericidal activity and effectively induced 5.9 and 5.8 log reduction of MRSA counts in mouse subeschar, respectively. Further, CGS19 and CGS20 kill bacteria not only through disturbing membrane integrity but also by binding formate-tetrahydrofolate ligase, a key enzyme in the folate metabolism pathway, thereby inhibiting the folate pathway of MRSA. CGS19 and CGS20 are promising lead candidates for drug development against MRSA infection. The dual mechanisms on the identical peptide sequence or scaffold might be an underappreciated manner of treating life-threatening pathogens.

Deep Eutectic Solvent and Poly (Vinyl Alcohol) Based Self‐healable, Injectable and Adhesive „Eutectogel”: An Emerging Drug Delivery Vehicle

AbstractMultifunctional polymeric eutectogel with characteristics such as self‐healing, adhesive, moldable, load bearable and penetrable through the stratum corneum layer of skin is vital for designing highly efficient platform for the new age sustained transdermal drug delivery. Inspired by the sea cucumber, which can loosen and tighten its body and merge collagen fibers to regain firmness, a biomimetic multifunctional polymeric eutectogel with above mentioned characteristics is developed here through interacting natural deep eutectic solvent (NADES) with poly (vinyl alcohol) (PVA). Hydrogen bonding interactions responsible for the formation of eutectogel, its porous three‐dimensional fibrous network morphology and mechanical strength as well as thixotropic behavior were assessed using state of the art analytical techniques. The eutectogel also exhibited multifunctional properties such as phase transition, in‐vitro degradation and stability as a function of temperature, pH and salt concentration, respectively apart from its multifunctional characteristics. The eutectogel‐bound cotton patch with high absorptivity and stability (750 % high) of curcumin was developed. The eutectogel was further investigated for its potential as the transdermal delivery vehicle for the encapsulation and delivery of anticancer drug, 5‐Fluoro Uracil. Skin permeation study and chemotherapeutic activity against MCF‐07 human breast cancer cell lines were evaluated, showing promising results.

Integrated microbiomics and metabolomics analysis reveals the influence of gut microbiota on the growth and metabolism of sea cucumber seedlings.

This study explores the impact of gut microbiota on body metabolites and the growth rate of sea cucumber seedlings. A comprehensive analysis using metabolomics and microbiomics was conducted to ascertain the gut microbiota and body metabolites in sea cucumber seedlings exhibiting varying growth rates. Distinct changes in the intestinal flora were observed in correlation with different growth rates of sea cucumber seedlings. The microbial communities of faster-growing seedlings exhibited greater diversity and evenness of taxa. For example, the abundance of genera Rhodococcus, Woeseia, Lysobacter, Desulfuromonadia_Sva1033, and Flavobacteriaceae_NS5_marine_group was more than 24 times higher in the fast-growing group compared to the slow-growing group. Metabolomics analysis revealed an association between high growth rates of cucumber seedlings and discrepancies in metabolites, such as amino acids, lipids, and carbohydrates. Isorenieratene, possibly synthesized by Rhodococcus, was more than 2.5 times more abundant in the fast-growing group than the slow-growing group. Slow-growing seedlings showed considerable enrichment of environmental pollutants, such as antibiotics and drugs, while their colonies were devoid of bacteria capable of degrading such pollutants. In addition, significant differences were observed between groups in the biosynthesis of amino acids, metabolism of arginine and proline, biosynthesis of unsaturated fatty acids, and metabolism of linoleic acid. Moreover, significant correlations between the microbial genera and sea cucumber metabolites were identified through correlation analysis. Significant differences exist in the gut microbiota and metabolite composition among seedlings with varying growth rates. Microbes residing in the gut have the potential to influence the growth of seedlings through modulation of their metabolism.

Diversity and characterization of culturable fungi associated with the marine sea cucumber Holothuria scabra.

Fungi associated with the marine echinoderm, Holothuria scabra, produces extracellular enzymes and bioactive metabolites, and mycoviruses that could be used for biotechnological and pharmaceutical applications. The species identification based on molecular and morphological characteristics classified the culturable fungi into twenty-three genera belonging to eight orders, Chaetothyriales, Eurotiales, Hypocreales, Mucorales, Mycosphaerellales, Onygenales, Pleosporales and Venturiales, from four classes, Eurotiomycetes, Dothideomycetes, Mucoromycetes and Sordariomycetes of the two phyla Ascomycota and Mucoromycota. The most frequent genera were Aspergillus (relative frequency, 45.30%) and Penicillium (relative frequency, 22.68%). The Menhinick species richness and Shannon species diversity indices were 1.64 and 2.36, respectively, indicating a high diversity of fungi. An enzymatic production test revealed that sixteen isolates could produce proteases and amylases at different levels. The presence of mycoviruses was detected in eight isolates with different genomic profiles. Thirty-two of the 55 isolates produced antimicrobial metabolites which had an inhibitory effect on various microbial pathogens. Most of these active isolates were identified as Aspergillus, Penicillium and Trichoderma. Notably, Aspergillus terreus F10M7, Trichoderma harzianum F31M4 and T. harzianum F31M5 showed the most potent activity against both Gram-positive and Gram-negative bacteria and human pathogenic fungi. Our study represents the first report of the mycobiota associated with the marine echinoderm Holothuria scabra.

A high-quality chromosomal genome assembly of the sea cucumber Chiridota heheva and its hydrothermal adaptation.

Chiridota heheva is a cosmopolitan holothurian well adapted to diverse deep-sea ecosystems, especially chemosynthetic environments. Besides high hydrostatic pressure and limited light, high concentrations of metal ions also represent harsh conditions in hydrothermal environments. Few holothurian species can live in such extreme conditions. Therefore, it is valuable to elucidate the adaptive genetic mechanisms of C. heheva in hydrothermal environments. Herein, we report a high-quality reference genome assembly of C. heheva from the Kairei vent, which is the first chromosome-level genome of Apodida. The chromosome-level genome size was 1.43 Gb, with a scaffold N50 of 53.24 Mb and BUSCO completeness score of 94.5%. Contig sequences were clustered, ordered, and assembled into 19 natural chromosomes. Comparative genome analysis found that the expanded gene families and positively selected genes of C. heheva were involved in the DNA damage repair process. The expanded gene families and the unique genes contributed to maintaining iron homeostasis in an iron-enriched environment. The positively selected gene RFC2 with 10 positively selected sites played an essential role in DNA repair under extreme environments. This first chromosome-level genome assembly of C. heheva reveals the hydrothermal adaptation of holothurians. As the first chromosome-level genome of order Apodida, this genome will provide the resource for investigating the evolution of class Holothuroidea.

Activity of Sea Cucumber and Spirulina in Wound Healing and Blood Glucose Decreasing in Streptozotocin- Induced Diabetic Rats

Previous study showed that sea cucumber and spirulina had an antioxidant activity and antihyperglycemic activity. Sea cucumbers contain a cell growth factor that is useful in wound healing. This research aimed to determine the activity of sea cucumber and spirulina in decreasing the fasting blood glucose and wound healing process in streptozotocin-induced diabetic rats. The antihyperglycemic activity and wound healing test were done to experimental rats that have been conditioned with diabetic wound. 2840 mg/kg body weight of liquid preparation of sea cucumber methanol extract and 81 mg/kg body weight of spirulina extract were given through oral gavage and sea cucumber methanol extract was given topically once a day. The results showed that group of golden sea cucumber orally-topically had the best antihyperglycemic activity with the highest percentage reduction in blood glucose level while group of golden sea cucumber topically-spirulina orally had the best wound healing effect with the highest percentage of wound healing.

Extraction and characterization of collagen and gelatin from body wall of sea cucumbers Stichopus horrens and Holothuria arenicola.

Marine invertebrates, including sponges, molluscs, jellyfish, mussels, and sea cucumbers, are abundant sources of high-quality collagen and offer advantages such as availability, ease of processing, lower inflammatory response, and good metabolic compatibility. Approximately 70% of the total protein in the body wall of sea cucumbers is collagen. Gelatin is a water-soluble protein produced from heat-denatured collagen and has various industrial applications. Pepsin-solubilized collagen was extracted from the body wall of two sea cucumber Stichopus horrens and Holothuria arenicola, species found in the Oman Sea and characterized with SDS-PAGE and amino acid composition. Then gelatin was extracted from pepsin-solubilized collagen of S. horrens and some rheological properties were measured. Amino acid composition and SDS-PAGE analysis showed that the collagen from both species was type I, with one α1 chain and β chains, with molecular weights of 125 and 250 kDa, respectively. Glycine was the most abundant amino acid in the collagen from both sea cucumber species. The pepsin-soluble collagens from both species had high levels of glycine, proline, alanine, glutamic acid, and hydroxyproline. The gelatin from S. horrens had a melting point of 30 °C and displayed exceptional thermal stability, surpassing that of mammalian gelatin. Its gelling point was 5 °C, like that of cold-water fish gelatin, with a viscosity of 2.065 cp-lower than mammal gelatins. These findings suggested that collagen and gelatin from sea cucumbers could be useful in nutraceutical, pharmaceutical and cosmetic industries.

Fission technique on sea cucumbers (Holothuroidea): An alternative method for seed production

This study aimed to determine the successive level of fission technique on several sea cucumbers (Holothuroidea) in littoral zone of Madong Bay, Tanjungpinang. The fission technique was performed by tying the middle part of the sea cucumber’s body using a rubber band. Parameters observed were composed of: (a) the occurrence of autotomy on pre- and post-treatment period, (b) successive rate of fission technique (%), (c) fission duration, (d) survival rate on post-treatment period. All data were analyzed descriptively. The results showed that: (1) Only gold sea cucumber Stichopus chloronotus that could perform autotomy on post- treatment period, (2) The successive rate of fission technique on Stichopus chloronotus and Holothuria atra was 83.33% and 33.33%, respectively, while fission was absent on Holothuria scabra and Holothuria sp. (0%), (3) The fastest fission process was found on Stichopus chloronotus at 1.2 hours, after applying the fission technique at 24±2 hours and Holothuria atra was at 24-48 hours, (4) The survival rate on post-treatment period was 66.67% in Stichopus chloronotus and 41.67% in Holothuria atra, while Holothuria scabra was 66.67% and Holothuria sp. was 11.11%. Fission technique is more suitable for Stichopus chloronotus as an alternative method for seed supply in grow-out culture activities.

The neuroprotective effects of SFGDI on sirtuin 3-related oxidative stress by regulating the Sirt3/SOD/ROS pathway and energy metabolism in BV2 cells.

Recently, the investigation of neuroprotective peptides has gained attention in addressing memory impairment and cognitive decline. Although the potential neuroprotective peptide Serine-Phenylalanine-Glycine-Aspartic acid-Isoleucine (SFGDI) has been identified from sea cucumber, the molecular mechanisms remain unclear. This study was conducted to explore the neuroprotection of SFGDI against 3-TYP-induced oxidative stress in BV2 cells. The results showed a retention rate of 76.70% during in vitro simulated gastrointestinal digestion and an absorption rate of 10.41% in a rat-everted gut sac model for SFGDI. Two hours following the administration of SFGDI via gavage in mice, a notable fluorescence was observed in the brain, indicating a potential neuroprotection of SFGDI through its interactions with nerve cells. By utilizing a model of oxidative stress injury induced by 3-TYP in BV2 cells, it was determined that pretreatment with SFGDI (50-200 μg mL-1) resulted in a dose-dependent reduction in the acetylated SOD level, leading to enhanced SOD activity and reduced levels of ROS and MDA. In addition, this pretreatment triggered an increase in unsaturated lipid levels, which helped maintain the intracellular lipid metabolism balance and preserve the mitochondrial function and glycolysis levels to regulate energy metabolism. The results of this study indicate that SFGDI demonstrates neuroprotective properties through its modulation of the Sirt3/SOD/ROS pathway, regulation of lipid metabolism, and enhancement of energy metabolism in BV2 cells. These findings suggest potential novel therapeutic approaches for addressing Sirt3-related memory deficits and neurodegenerative disorders.