Search Results (9)

This study comprehensively evaluates the phenotypic traits, nutritional profiles, and genetic diversity of three cultured populations of Portunus pelagicus from Guangdong Province, China, namely from Shenzhen (PpSZ), Zhuhai (PpZH), and Chaozhou (PpCZ). We analyzed key nutritional components, including moisture, ash, crude fat, crude protein, total sugar, amino acids, and fatty acids. Notably, significant differences in total sugar content (p < 0.05) were observed among populations, whereas no substantial variation was detected in the other nutritional parameters. PpSZ exhibited significantly higher levels of specific amino acids, especially essential amino acids (p < 0.05). Fatty acid composition revealed a more favorable nutritional profile in PpZH. Analysis of physiological markers such as total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and catalase (CAT) activities demonstrated comparable levels across populations, with no significant differences. Genetic diversity assessment revealed SNP densities of 6.583, 6.16, and 6.08 SNPs/Kb for PpSZ, PpZH, and PpCZ, respectively. The low polymorphism (PIC < 0.25) indicates limited genetic variation within the species. This study provides valuable insights into the biochemical, nutritional, and genetic characteristics of these populations, offering critical implications for the optimization of aquaculture practices and the conservation of genetic resources for this economically significant species. Full article

Crabs are the most widely studied marine crustaceans due to their high economic value, ecological significance, and worldwide range in the subtropics and tropics zones. In this study, we adopted a molecular barcoding approach for rapid identification of blue crab species by sequencing the mitochondrial cytochrome c oxidase subunit I gene (COI), which has previously been used for phylogenetic analysis in wide taxonomic groups, and particularly for Crustaceans. The results indicated the evidence of Callinectes sapidus and Portunus pelagicus in different localities along Tunisian coast. Data were confirmed by BLAST analysis (Basic Local Alignment Tool) and phylogenetic trees. The molecular identification showed the ability of the COI region to differentiate between two similar blue crab species, Portunus segnis and Portunus pelagicus, which were confused by morphological analysis. The adoption of this protocol may be useful in revealing the biogeography of these invasive species across Mediterranean and to support the authentication of crab-meat processed products, according to the normative control. Full article

Bone tissue engineering (BTE) provides an alternative for addressing bone defects by integrating cells, a scaffold, and bioactive growth factors to stimulate tissue regeneration and repair, resulting in effective bioengineered tissue. This study focuses on repurposing chitosan from blue swimming crab (Portunus pelagicus) shell waste as a composite scaffold combined with HAP and COL I to improve biocompatibility, porosity, swelling, and mechanical properties. The composite scaffold demonstrated nearly 60% porosity with diameters ranging from 100–200 μm with an interconnected network that structurally mimics the extracellular matrix. The swelling ratio of the scaffold was measured at 208.43 ± 14.05%, 248.93 ± 4.32%, 280.01 ± 1.26%, 305.44 ± 20.71%, and 310.03 ± 17.94% at 1, 3, 6, 12, and 24 h, respectively. Thus, the Portunus pelagicus scaffold showed significantly lower degradation ratios of 5.64 ± 1.89%, 14.34 ± 8.59%, 19.57 ± 14.23%, and 29.13 ± 9.87% for 1 to 4 weeks, respectively. The scaffold supports osteoblast attachment and proliferation for 7 days. Waste from Portunus pelagicus shells has emerged as a prospective source of chitosan with potential application in tissue engineering. Full article

In Thailand, the populations of a commercially important crab Portunus pelagicus (Linnaeus, 1758) have been decreasing due to overfishing, raising concerns about the conservation efforts of this crab species. The Crab Bank Project has recently been established to restore crab populations by releasing crab larvae from each crab bank station. However, the fate of crab larvae after the release is poorly understood. Here, we assessed the dispersal and settlement patterns of the larvae P. pelagicus released from crab banks along the coast of Trang Province, Southern Thailand. The Lagrangian particle tracking model was employed to simulate the larval dispersal and settlement patterns after release from the crab banks during the inter-monsoon, southwest monsoon, and northeast monsoon. Our simulation revealed that virtual larvae were predominantly retained within inshore areas after the release for 14 days, regulated by tidal-driven currents, wind-induced currents, and local coastal topography. Monsoon periods affected the larval dispersal, with some larvae being transported into estuaries due to the SW monsoonal effects. After the 14-day release period, our modelled simulations suggested that the crab larvae arrived at numerous seagrass meadows along the coast, indicating potential settlement and growth. This result highlights the connectivity of sources and sinks for crab larvae after release from crab banks. Moreover, significant implications for conservation efforts and the fishery management of P. pelagicus were also discussed based on our modelled simulations. Full article

Peptic ulcer disease is generated by the activation of NF-kappaB activity. A recent clinical study reported a significant increase in NF-kappaB2 gene expression in 79 samples of peptic ulcer patients compared to the control group. Moreover, the deacetylated chitin could alter the translocation of NF-kappaB p65 to the nucleus. Considering this, our work aims to explore the effect of chitin extracted from the shell of blue swimming crabs (Portunus pelagicus Linn.) towards NF-kappaB p65 levels in ethanol-induced gastric ulcerative Wistar rats. The shells are found abundantly as the waste of seafood processing in the northern part of West Java, Indonesia. In this study, chitin extraction was carried out using the microwave-assisted extraction method by employing choline chloride (C₅H₁₄ClNO) and DL-malic acid (C₄H₆O₅) as the solvents. The inhibitory activity assay of chitin on the expression of NF-kappaB p65 was performed by using Western blot. The extraction yielded a good quality of chitin with a deacetylation degree of 30.8026%, molecular weight of 3.35 × 10⁵ Da, and a negligible heavy metals level. Moreover, chitin extract at doses of 150, 300, and 600 mg/kg BW significantly reduced the percentage of gastric ulcer index compared to the negative control group. Meanwhile, chitin extract at doses of 300 and 600 mg/kg BW significantly inhibited NF-kappaB expression compared to the negative control group. Histopathological examination demonstrated a decrease in the number of necrotic cells and fat degeneration in the gastric mucosa and an increase in normal cells. Taken together, chitin extract obtained from the shells of blue swimming crabs may be able to prevent gastric ulcers induced by ethanol via the inhibition of NF-kappaB p65; however, further studies are needed to verify its anti-ulcerative properties. Full article

Heavy metal pollution can adversely impact marine life, such as crabs, which can accumulate it in different organs and potentially transfer and biomagnify along the food chain in aquatic ecosystems. This study aimed to examine the concentrations of heavy metals (Cd, Cu, Pb, and Zn) in sediment, water, and crab tissues (gills, hepatopancreas, and carapace) of the blue swimmer crab Portunus pelagicus in the coastal areas of Kuwait, northwestern Arabian Gulf. Samples were collected from Shuwaikh Port, Shuaiba Port, and Al-Khiran areas. The accumulation of metals in crabs were higher in the carapace > gill > digestive gland, and the highest metal concentration was found in crabs collected from Shuwaikh > Shuaiba > Al-Khiran. The metal concentrations in the sediments were in the order Zn > Cu > Pb > Cd. Zn was the highest metal concentration detected in marine water sampled from the Al-Khiran Area, whereas the lowest metal was Cd sampled in water from the Shuwaikh Area. The results of this study validate the marine crab P. pelagicus as a relevant sentinel and prospective bioindicator for evaluating heavy metal pollution in marine ecosystems. Full article

Blue swimmer crabs (Portunus pelagicus) primarily inhabit the coastal regions of Southeast Asia. This study aimed to examine their population genetic structure, phylogeography, and historical demography by applying partial sequences to the control region in the mitochondrial DNA. The analysis focused on 6 populations comprising 166 individual samples collected from Taiwan (Kezailiao Kaohsiung (KK) and Penghu (PH)), mainland China (Xiamen (XM) and Hong Kong (HK)), Vietnam (Hanoi (VN)), and Singapore (SGP). The estimated nucleotide diversity (π) for all of the samples was 0.062, with values ranging between 0.018 (PH) and 0.045 (HK). Our study collected 116 haplotypes and classified them into lineages A and B. The XM, HK, VN, and SGP populations made up lineage A, and the PH and KK populations comprised lineage B. For each lineage, the results highlighted indications of demographic expansion. Lineage A can be traced back to the second-to-last interglacial period, while lineage B possibly originated in the last glacial period. There were significant differences in the F_ST values among the six populations, except for the pairs HK–XM and PH–KK. In conclusion, the phylogeography and genetic structure of P. pelagicus in Southeast Asia were potentially affected by the Pleistocene glacial cycles and human introduction. These findings further highlight the possible dispersal routes of P. pelagicus throughout Southeast Asia. Full article

Information regarding the oceanic environment is crucial for determining species distributions and their habitat preferences. However, in studies on crustaceans, especially swimming crabs, such information remains poorly utilized, and its effects on crab communities in the Taiwan Strait (TS) has not been well documented. The purpose of this study was to understand the relationship between the catch rates of three swimming crab species and environmental factors in the TS. We fitted generalized additive models (GAMs) to logbooks and voyage data recorder data from Taiwanese crab vessels (2011–2015), developed a species distribution model, and predicted catch rates for these three swimming crab species based on the GAM output. The chlorophyll-a (Chl-a) concentration was related to the high catch rates of Chrybdis feriatus and Portunus sanguinolentus, whereas bottom temperature (BT) was related to high catch rates of Portunus pelagicus. The variance percentages for each crab species indicated that high catch rates of C. feriatus and P. sanguinolentus occurred in a Chl-a concentration > 0.5 mg/m³, whereas P. pelagicus catch rates exhibited negative correlations with BTs > 25 °C. The model predicted high catch rates of C. feriatus in the north of the TS during autumn and winter, whereas P. pelagicus was observed to the south during summer and autumn. P. sanguinolentus was predicted to be widely distributed around the TS and distributed further to the northern area during autumn and winter. These findings revealed that each species responds to spatiotemporal environmental variations. Understanding the distributions and habitats of these three crabs is vital in fisheries resource management and conservation planning. Full article

Therapeutic options for Alzheimer’s disease, the most common form of dementia, are currently restricted to palliative treatments. The glycosaminoglycan heparin, widely used as a clinical anticoagulant, has previously been shown to inhibit the Alzheimer’s disease-relevant β-secretase 1 (BACE1). Despite this, the deployment of pharmaceutical heparin for the treatment of Alzheimer’s disease is largely precluded by its potent anticoagulant activity. Furthermore, ongoing concerns regarding the use of mammalian-sourced heparins, primarily due to prion diseases and religious beliefs hinder the deployment of alternative heparin-based therapeutics. A marine-derived, heparan sulphate-containing glycosaminoglycan extract, isolated from the crab Portunus pelagicus, was identified to inhibit human BACE1 with comparable bioactivity to that of mammalian heparin (IC₅₀ = 1.85 μg mL⁻¹ (R² = 0.94) and 2.43 μg mL⁻¹ (R² = 0.93), respectively), while possessing highly attenuated anticoagulant activities. The results from several structural techniques suggest that the interactions between BACE1 and the extract from P. pelagicus are complex and distinct from those of heparin. Full article