Search Results (1,431)

Alzheimer’s disease (AD), a multifactorial neurodegenerative disorder characterized by severe cognitive impairment, affects millions of people worldwide. However, AD therapy remains limited and mainly symptomatic-focused, with acetylcholinesterase (AChE) inhibitors being the major available drugs. Thus, AD is considered by the WHO as a disorder of public health priority. Among several strategies that have been identified to combat AD, the use of natural multi-target drug ligands (MTDLs) appears to be a promising approach. In this context, we previously found that the essential oils (EOs), obtained via hydrodistillation, from Azorean Cryptomeria japonica sawdust (CJS) and resin-rich bark (CJRRB) were able to exert antioxidant activity via different mechanisms of action. Therefore, in the present work, these EOs were screened for their (i) in vitro anti-AChE and anti-butyrylcholinesterase (BChE) activities, evaluated by a modified Ellman’s assay; (ii) in vitro anti-inflammatory potential, using the albumin denaturation method; and (iii) toxicity against Artemia salina. The CJRRB–EO exhibited both anti-AChE and anti-BChE activities (IC₅₀: 1935 and 600 µg/mL, respectively), whereas the CJS–EO only displayed anti-BChE activity, but it was 3.77-fold higher than that of the CJRRB–EO. Molecular docking suggested that α-pinene and ferruginol compounds contributed to the anti-AChE and anti-BChE activities, respectively. Moreover, the anti-inflammatory activity of the CJS–EO, the CJRRB–EO, and diclofenac was 51%, 70%, and 59% (at a concentration of only 2.21 μg/mL), respectively, with the latter two presenting comparable activity. Concerning the EOs’ potential toxicity, the CJRRB–EO exhibited a lower effect than the CJS–EO (LC₅₀: 313 and 73 µg/mL, respectively). Overall, the EOs from C. japonica biomass residues, chiefly the CJRRB–EO, displayed antioxidant, anticholinesterase, and anti-inflammatory activities in a concentration-dependent manner. These properties demonstrate that these residues may be suitable natural MTDLs for AD complementary therapy when administered through aromatherapy, or, alternatively, could serve as low-cost sources of valuable ingredients, such as α-pinene. Full article

Vibrio alginolyticus frequently breaks out in aquatic animal breeding operations involving shrimp, and it can endanger human health through food and wound infections. The antibacterial effect and mechanism of fermented pomegranate peel polyphenols (FPPPs) on V. alginolyticus were investigated. The results indicated that FPPPs had a strong inhibitory effect on the growth of V. alginolyticus, and their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were 2 and 4 mg/mL. FPPPs significantly reduced biofilm formation and biofilm metabolic activity in V. alginolyticus, down-regulated the expression levels of lafA, lafK, fliS and flaK genes involved in flagellar synthesis and inhibited swimming and swarming motility (p < 0.05). Meanwhile, under the treatment of FPPPs, the activities of catalase (CAT) and superoxide dismutase (SOD) in V. alginolyticus were significantly reduced, and the levels of reactive oxygen species (ROS) and extracellular malondialdehyde (MDA) were significantly increased (p < 0.05). FPPPs also resulted in a significant increase in alkaline phosphatase (AKP) activity, protein and nucleic acid content, as well as conductivity from V. alginolyticus cultures. Scanning electron microscopy (SEM) images further revealed that V. alginolyticus treated with FPPPs showed leakage of intracellular substances, abnormal cell morphology and damage to cell walls and cell membranes, with the severity of the damage in a clear dose-dependent manner. Therefore, FPPPs can be used as a promising food-grade antibacterial agent, notably in seafood to control V. alginolyticus. Full article

Carbonate alkalinity (CA) is the major toxic factor that interferes with the survival and growth of shrimp in saline–alkaline water. Gills are the main entry organ for CA toxicity in shrimp. In this study, low-salinity cultured Litopenaeus vannamei were exposed to 5 mmol/L CA stress for 7 days and then recovered for 7 days to explore the physiological changes in the gills under CA stress and recovery conditions at multiple biological levels. The results showed that CA stress increased the activities of antioxidative biochemical indexes (T-AOC, T-SOD, and POD) and the relative expression levels of romo1, nrf2, and gpx genes, while it decreased the relative expression levels of the sod and hsp70 genes. In addition, CA stress also increased the relative expression levels of genes involved in endoplasmic reticulum (ER) stress (bip, ire1, and xbp1), immunity (alf, crus, pen-3, lys, and propo), apoptosis (casp-3), detoxification metabolism (cyp450 and gst), and osmotic adjustment (ca, nka-α, nka-β, vatp, nhe, clc, aqp, tip4, and ccp). Although changes in some of the physiological indexes were reversed after the CA stress was relieved, they still could not effectively recover to the control level. These results reveal that CA stress has a negative impact on physiological homeostasis in the shrimp gills by inducing oxidation and ER stress and by interfering with immunity, apoptosis, detoxification, and osmotic adjustment. Full article

Conventional energy-absorbing components have limited adjustability under complex working conditions. To overcome this limitation, we designed a bio-inspired sinusoidal metamaterial (BSM) inspired by the efficient energy-absorbing structure of the mantis shrimp jaw foot and 4D printed it based on shape-memory polymer (SMP). The effects of single-cell structural parameters and gradient design on its force–displacement curves and energy-absorbing properties were explored. Based on the shape memory effect of SMP, the BSM can obtain arbitrary temporary shapes under the combined effect of temperature and force, realizing locally controllable compression deformation and programmable mechanical properties of the BSM structure. This research has a broad application prospect in the field of energy absorption and energy management and provides new ideas for the design of smart structural materials. Full article

The best practice for killing decapod crustaceans lacking a centralized ganglion has been debated for a century. Currently, there is a movement away from live boiling towards electrocution and mechanical splitting or spiking, which are efficient in the large commercial setting but may be unavailable and impractical for small decapods such as shrimp and prawn in the small-scale setting of, e.g., the household. Here, using carcasses of varying sizes of prawn, crayfish, lobster and green and brown crab, we used micro-CT imaging to measure surface area and sphericity in relation to body mass. Then, we measured heating profiles at the anterior ganglion and in the core of carcasses of the same species when exposed to standardized boiling regimes. We found a relationship with positive allometry between surface area and body mass for all species and a decrease in sphericity with mass. Heating times until proposed stunning (26 °C) and killing (44 °C) varied with body size and starting temperature and exceeded minutes for larger species. For a small species like prawn, times to stunning and killing by boiling are comparable to electrocution times and within the acceptable range compared to recreational killing of other sentient beings such as game mammals. Full article

Bacteria from genus Vibrio continue to be one of the most common threats to aquaculture sustainability. Vibrio spp. have been associated with infectious outbreaks in fish, shrimp, bivalves and even algae farms worldwide. Moreover, several Vibrio spp. are also pathogens that impact human health and are a threat to public health when transferred to consumers through contaminated seafood products. The use of bacteriophages is an evolving technology that could be applied in the treatment of Vibrio spp. either to protect aquaculture farms or to decontaminate seafood, namely bivalves during their depuration. In the present study, bacteriophages vB_VpS_LMAVpS1 (S1) vB_VpS_LMAVpVPP (VPP), vB_VpS_LMAVpSH (SH) and vB_VpS_LMAVpH (H) infecting V. parahaemolyticus were isolated and characterized. All phages presented fast adsorption rates and were able to control V. parahaemolyticus at all multiplicity of infections (MOIs) tested (MOI of 1, 10 and 100), with reductions of more than 4 log CFU/mL being recorded, but only in the presence of divalent cation calcium. The rate of emergence of phage-resistant mutants was very low (1.8 × 10⁻⁶ to 3.1 × 10⁻⁶). Bacterial phage resistance was not permanent and led to a loss of bacterial fitness. All four phages presented with lysins encoded in their genomes. The results presented provide valuable insights for future studies in the application of these bacteriophages in different scenarios to control, decontaminate or treat bacterial infections or contaminations of V. parahaemolyticus. Full article

Vibrio harveyi is a serious bacterial pathogen which can infect a wide range of marine organisms, such as marine fish, invertebrates, and shrimp, in aquaculture, causing severe losses. In addition, V. harveyi can be transmitted through food and water, infecting humans and posing a serious threat to public safety. Therefore, rapid and accurate detection of this pathogen is key for the prevention and control of related diseases. In this study, nine rounds of in vitro screening were conducted with Systematic Evolution of Ligands by Exponential Enrichment (SELEX) technology using unmodified DNA libraries, targeting the crude extracellular matrix (CEM) of V. harveyi. Two DNAzymes, named DVh₁ and DVh₃, with high activity and specificity were obtained. Furthermore, a fluorescent biosensor with dual DNAzymes was constructed which exhibited improved detection efficiency. The sensor showed a good fluorescence response to multiple aquatic products (i.e., fish, shrimp, and shellfish) infected with V. harveyi, with a detection limit below 11 CFU/mL. The fluorescence signal was observed within 30 min of reaction after target addition. This simple, inexpensive, highly effective, and easy to operate DNAzymes biosensor can be used for field detection of V. harveyi. Full article

The application of whole-genome resequencing in genetic research is rapidly expanding, yet the impact of sequencing depth on data quality and variant detection remains unclear, particularly in aquaculture species. This study re-sequenced 31 Litopenaeus vannamei (L. vannamei) samples at over 28× sequencing depth using the Illumina NovaSeq system and down-sampled the data to simulate depths from 0.5× to 20×. Results showed that when the sequencing depth was below 10×, the number of SNP identifications increased sharply with the rise in depth, with single nucleotide polymorphisms (SNPs) detected at 10× accounting for approximately 69.16% of those detected at 20×. The genotyping accuracy followed a similar trend to SNP detection results, being approximately 0.90 at 6×. Further analyses showed that the main cause of genotyping errors was the misidentification of heterozygous variants as homozygous variants. Therefore, considering both the quantity and quality of SNPs, a sequencing depth of 10× is recommended for whole-genome studies and genetic mapping, while a depth of 6× is more cost-effective for population structure analysis. This study underscores the importance of selecting optimal sequencing depth to ensure reliable variant detection and high data quality, providing valuable guidance for whole-genome resequencing in shrimp and other aquatic species. Full article

Carbon dots (C-Dots) have garnered significant attention in various fields, including biomedical applications, photocatalysis, sensing, and optoelectronics, due to their high luminescence, biocompatibility, and ease of functionalization. However, concerns regarding their potential toxicity persist. Conventional synthesis methods for C-Dots often require long reaction times, high pressures, expensive equipment, extreme temperatures, and toxic reagents. In contrast, microwave irradiation provides a rapid, cost-effective, and scalable alternative for the synthesis of high-quality C-Dots. In this study, we report the single-step, 3-min synthesis of water-stable carbon dots at 100 °C, 120 °C, and 140 °C using microwave irradiation. Particle stability was achieved through polyethyleneimine (PEI) functionalization. The toxicity of the synthesized carbon dots was evaluated in marine crustaceans, revealing that C-Dots with an estimated size below 10 nm did not exhibit toxicity after 24 and 48 h of exposure. These findings demonstrate the potential of microwave-synthesized carbon dots as non-toxic, water-stable nanomaterials for environmental and biomedical applications. Full article

Clam shrimps are one of the most common and representative invertebrates in continental strata and are endowed with important biostratigraphic and paleoecological values. The genus Euestheria is one of the most common clam shrimp taxa that has been recorded in the latest Paleozoic and the Mesozoic around the world. A list of all the species assigned to Euestheria, recorded from the Devonian to the Cretaceous across all seven continents as of September 2024, is provided. The list may serve as a valuable resource, potentially useful for the biostratigraphic division and long-range correlations of continental strata. In addition, the taxonomic issues of the genus are briefly introduced and examined herein. The study aims to provide a simple lead-in for all the researchers who have an interest in clam shrimp and the genus Euestheria. Full article

Although phloretin is widely utilized in the food industry as an additive, its effects on foodborne pathogens remain insufficiently investigated. This study aimed to evaluate the antimicrobial properties of phloretin (PHL) against Vibrio parahaemolyticus (V. parahaemolyticus) and to elucidate the potential mechanisms of action. After PHL treatment, alterations in the cell morphology, cell microstructure, and intracellular contents of V. parahaemolyticus were assessed. Scanning electron microscopy revealed substantial damage to cell integrity, subsequent to PHL treatment. A notable reduction in intracellular components, including proteins, ATP, and DNA, was observed in samples treated with PHL. PHL was shown to inhibit the activities of ATPase, β-galactosidase, and respiratory chain dehydrogenase in V. parahaemolyticus. Furthermore, it was demonstrated to elevate the intracellular levels of reactive oxygen species and promote cell death. After being applied to sea bass, shrimp, and oysters, PHL effectively inactivated V. parahaemolyticus in these seafoods. These findings demonstrate that PHL has potential for application in seafood to control V. parahaemolyticus. Full article

The increasing installation of shrimp farms in vulnerable coastal areas around the world generates an environmental impact and makes it urgent to develop methodologies and studies for assessing and scaling the potential risks and sustainability of these activities. One of the main hazards of these activities is that the prolonged inundation of excavated ponds for shrimp farming allows the percolation of saltwater in the surroundings, resulting in increasing groundwater salinity. Saltwater intrusion in coastal aquifers, accompanied by salinization of soils, causes a decrease in available freshwater resources, a decline in crop productivity and the deterioration of the natural ecosystem. The coastal aquifer of Rio Grande do Norte State (Brazil) where, for years, several shrimp farm factories have been operating, reported some issues related to aquifer and soil salinization. The present study aims to assess the origin of and delineate groundwater salinization in a sector of this coastal aquifer using a low-budget procedure. The integration of hydrogeological and hydrogeochemical characterization by drilling shallow piezometers, measuring the hydrostatic level and analyzing the major ion concentrations of the groundwater has made it possible to establish that the origin of groundwater pollution in the studied area is caused by saltwater percolation from shrimp farms. The joint use of both characterization techniques has been shown to have an efficient cost–benefit ratio and less-intrusive methodology, which can be applied in other areas with similar environmental concerns. Full article

Aquaculture is one of the key economic activities to reduce food shortages worldwide. Water recirculation systems using pumps are crucial to maintain oxygenation and water quality, consuming about 35% of the total energy in this economic activity. This research proposes a multiple linear regression mathematical model to optimize oxygenation systems in intensive shrimp aquaculture by reducing energy consumption and minimizing water changes in ponds. The proposed model is key to optimizing the operation of pumping systems, allowing us to significantly reduce water turnover without compromising dissolved oxygen levels as a function of key variables such as water turnover volume, biomass, solar radiation (0–1200 W/m²), water temperature (20 °C–32 °C), phytoplankton levels (0–1,000,000 cells/ml), zooplankton (0–500,000 cells/ml), and wind speed (0–15 m/s). These variables are integrated into the model, managing to explain 94.02% of the variation in dissolved oxygen, with an R² of 92.9%, which adjusts the system conditions in real time, reducing the impact of environmental fluctuations on water quality. This leads to an estimated annual energy savings of 106,397.5 kWh, with a total consumption of 663.8 MWh. The research contributes to the development of a mathematical approach that not only improves oxygenation prediction, but also minimizes the use of water resources, improving the sustainability and profitability of shrimp farming systems, and is a robust tool that maximizes operational efficiency in intensive aquaculture, particularly where water and energy management are critical. Full article

Accurate water content detection is crucial for optimizing chemical reactions, ensuring product quality in pharmaceutical manufacturing, and maintaining food safety. In this study, nitrogen and sulfur co-doped graphene quantum dots (R-GQDs) were synthesized via a one-step hydrothermal method using o-phenylenediamine as the carbon source. The synthesis conditions, including reaction time, temperature, o-phenylenediamine concentration, and H₂SO₄/water ratio, were optimized using the Box-Behnken response surface methodology. The R-GQDs exhibited excellent fluorescence stability and distinct solvent-dependent characteristics, alongside a broad linear detection range and high sensitivity, making them highly suitable for dual-mode water content detection (colorimetric and fluorescent). To enhance the accuracy of visual detection, R-GQDs were incorporated into portable test strips with smartphone-assisted analysis, compensating for the human eye’s limitations in distinguishing subtle color changes. The sensor’s practical utility was validated through spiked recovery experiments in food samples, and the R-GQDs demonstrated good biocompatibility for in vivo imaging in shrimp. These findings highlight a novel strategy for developing portable, real-time water content sensors with potential applications in both portable detection systems and biological imaging. Full article

Specific strains of Vibrio parahaemolyticus can cause Acute Hepatopancreatic Necrosis Disease (AHPND), a critical issue in shrimp aquaculture despite the application of several control strategies. The use of antibiotics is now restricted due to increasing bacterial resistance and overuse. Silver nanoparticles (AgNPs) have shown potential in shrimp aquaculture, with applications in boosting immunity against certain types of pathogens, promoting growth, and improving survival rates. However, an economically viable solution that protects the organisms has not been found, which is why the search for nanoparticles synthesized with plant extracts is necessary to generate environmentally friendly control strategies. In this study, we synthesized AgNPs from Larrea tridentata extract and administered them orally with feed over a 35-day period. Shrimps fed with AgNP-enriched diets showed a significant increase (p < 0.05) in mRNA expression of immune-related genes (CTL-5, MNK, SR, and GILT), particularly within the first 24–48 h. No significant differences were observed in growth rates, but survival rates in a challenge against V. parahaemolyticus exceeded 85%, higher than the control group. Based on our findings and previous literature, L. tridentata can effectively promote the synthesis of AgNPs and shows potential as an antimicrobial agent, without affecting the growth or survival of treated shrimp. Full article