Performance of yellow and pink oyster mushroom dyes in dye sensitized solar cell.

A solar photovoltaic (PV) cell, is an electrical device that uses the PV effect to convert light energy into electricity. The application of oyster mushroom dyes in dye sensitized solar cell (DSSC) is a novel strategy to substitute the costly chemical production process with easily extractable, environmentally acceptable dyes. Both dyes of yellow and pink oyster mushrooms were extracted using the same process but dried into powder form using two techniques, warm drying and freeze drying. The characterization was carried out utilizing current-voltage (I-V) characterization for electrical properties, Ultraviolet-Visible (UV-Vis) spectrophotometer for optical properties, Field Emission Scanning Electron Microscopy (FESEM), and Atomic Force Microscopy (AFM) for the structural properties. It was found that freeze-dried pink and yellow oyster mushroom had shown the good properties for DSSC application as it produced energy bandgap which lies within the range of efficient dye sensitizer; 1.7 eV and 2.2 eV, the most uniform distribution of pores and a nearly spherical form in FESEM analysis, and AFM result obtained with the highest root mean square (RMS) roughness value (26.922 and 34.033) with stereoscopic morphologies. The data proved that mushroom dyes can be incorporated in DSSC with the optimization of drying method in the extraction process, dilution of dye and the layer of deposition on the glass substrate. The current density-voltage (J-V) characteristics of fabricated DSSC was characterized using Newport Oriel Sol3A solar simulator under AM 1.5 Sun condition (100 mW/cm2, 25 oC). From the result obtained by solar simulator, the fabricated FTO/TiO2/Pleurotus djamor dye/Pt indicated the Voc of 0.499 V and Jsc of 0.397 mA/cm2.

Using an ecosystem service model to inform restoration planning: A spatially explicit oyster filtration model for Pensacola Bay, Florida.

The development of science-based restoration goals that reflect the primary motivation of stakeholders is a key factor leading to large-scale, long-term restoration successes. The ability to predict the potential ecosystem service delivery from restoration can inform the setting of appropriate goals and facilitate the strategic planning of restoration activities. While recovery of the ecosystem services provided by oyster reefs is a regularly cited reason for undertaking restoration, few examples exist where large-scale oyster habitat restoration plans have been informed using ecosystem service functions. Such an approach is currently being implemented in the Pensacola Bay System, Florida, where a broad coalition of partners and community stakeholders are utilizing a watershed approach to restoring oysters with the aim of restoring oysters for multiple objectives including habitat, ecosystem services, and wild harvest and aquaculture. Through the process of developing a habitat management plan, water filtration was identified as a key ecosystem service by the stakeholders. To support restoration planning we derived a spatially explicit estimate of water filtration services provided by the eastern oyster in the Pensacola Bay system by linking an oyster habitat suitability map to a hydrodynamic-oyster filtration model. This spatially explicit model allowed us to identify the areas where restored oyster reefs have the potential to provide the greatest increase in filtration service as well as provide spatially explicit estimates of the potential filtration provided by oyster habitat restored. Such information is useful in restoration planning and management and for stakeholder engagement, outreach, and education programs.

Fabrication and characterization of novel glass-ionomer cement prepared from oyster shells.

Glass ionomer cement (GIC) is one of the most widely used restorative materials for temporary fillings and reconstructions in dentistry, but it has relatively poor mechanical properties that make its use limited, especially in places subject to high pressure. Thus, to extend the applicability of GIC, samples based on SiO2, P2O5, Al2O3, CaF2, and NaF were prepared with the addition of calcium oxide CaO extracted from natural sources (oyster shells) in different ratios of 0, 5, 10, 15, 20, and 25% wt. The suggested glass samples were evaluated, and their physical and mechanical properties were compared. XRD, SEM, and FTIR were performed on the samples. 24 specimens were prepared for each test in order to assess the mechanical properties as per the specific requirements. The tests included measuring bending strength, elastic modulus, adjusted direct tensile strength, absorption, water solubility, and diffusion coefficients after the specimens were stored in distilled water for 60 days. All calculations were carried out in accordance with standard procedures. The findings indicated a slight improvement in the bending resistance of the recommended GIC. Glass modified with 20% by weight of calcium oxide was the best among the ratios in terms of the results obtained and compared to the traditional commercial type. The malleable strength of the sample was 54.121 MPa, while the flexural modulus increased, the tensile strength reached 10.154 MPa, and the solubility was 25.87 µg/mm3 after storage for 60 days. These indicate that the developed material is suitable for use as a dental restoration material when compared to international commercial cement specifications.

Non-destructive Analytical Study of Raman Spectra Variations and Mechanisms of Calcite and Aragonite in Modern and Fossilized Oysters.

Oyster fossils are some of the most common bivalve mollusk fossils found all over the world, they are different from other fossils because the oyster is still alive in the present day, and the body structure of modern oyster is almost the same as that of ancient one. Therefore, we designed a control experiment comparing the Raman spectra of minerals from both modern oysters and fossil oysters to explore the mechanism of oyster's fossilization process, which is considered to be helpful for investigating biological evolution or paleoenvironment. The oyster fossil sample was found in Nagi-Cho, Okayama Prefecture, Japan. We focused on the variations of band position and full width half-maximum of ν1 Raman band (symmetric stretching mode) of calcite (CaCO3) from modern and fossil oysters and the mineral conversion between calcite and aragonite (CaCO3) around the adductor muscle inside the oyster. Compared to modern oysters, the ν1 band at around 1086 cm-1 of calcite from oyster fossils shifted to a high wavenumber region, and the possible reason for this phenomenon is considered an elemental substitution between Ca2+ and Mg2+. As for aragonite around adductor muscle in fossil oysters, it has been found by Raman spectra that most of the aragonite has been converted into calcite because calcite has a relatively more stable structure.

First multi-compartment approach to microplastics in an urbanized estuary of Argentina: The case of Magallana gigas.

This study assesses MP in water, sediment, gills, and digestive tract of the oyster Magallana gigas in three Bahía Blanca estuary sites, Argentina, using, Pollution Load Index (PLI) and SEM/EDX (Scanning Electron Microscopy with Energy-dispersive X-ray spectroscopy) and FTIR (Fourier-transform infrared spectroscopy) techniques. A total of 51 MPs were detected in water (mean: 16 items L-1) and 126 in sediments (mean: 1399 items Kg-1) with no significant differences between sites. In oysters, 186 MPs were found, with no significant differences in the MPs load between gills (mean: 2.41 items g-1 w.w), digestive tract (2.06 ± 2 items g-1 w.w), and the total tissues. Transparent fiber MPs were predominant, with cellulose, polyamides, polyethylene terephthalate and polyethylene being common polymers. SEM/EDX showed Si, Fe, Cl, Na, Ti, Al, K, Ca and suspended particulate matter on MP surfaces. The PLI indicated a low-risk level for estuary bivalves and water, suggesting minimal MPs impact.

Machine Learning-Driven Discovery and Evaluation of Antimicrobial Peptides from Crassostrea gigas Mucus Proteome.

Marine antimicrobial peptides (AMPs) represent a promising source for combating infections, especially against antibiotic-resistant pathogens and traditionally challenging infections. However, traditional drug discovery methods face challenges such as time-consuming processes and high costs. Therefore, leveraging machine learning techniques to expedite the discovery of marine AMPs holds significant promise. Our study applies machine learning to develop marine AMPs, focusing on Crassostrea gigas mucus rich in antimicrobial components. We conducted proteome sequencing of C. gigas mucous proteins, used the iAMPCN model for peptide activity prediction, and evaluated the antimicrobial, hemolytic, and cytotoxic capabilities of six peptides. Proteomic analysis identified 4490 proteins, yielding about 43,000 peptides (8-50 amino acids). Peptide ranking based on length, hydrophobicity, and charge assessed antimicrobial potential, predicting 23 biological activities. Six peptides, distinguished by their high relative scores and promising biological activities, were chosen for bactericidal assay. Peptides P1 to P4 showed antimicrobial activity against E. coli, with P2 and P4 being particularly effective. All peptides inhibited S. aureus growth. P2 and P4 also exhibited significant anti-V. parahaemolyticus effects, while P1 and P3 were non-cytotoxic to HEK293T cells at detectable concentrations. Minimal hemolytic activity was observed for all peptides even at high concentrations. This study highlights the potent antimicrobial properties of naturally occurring oyster mucus peptides, emphasizing their low cytotoxicity and lack of hemolytic effects. Machine learning accurately predicted biological activity, showcasing its potential in peptide drug discovery.

Heavy Metal Accumulation in Oysters from an Aquaculture Area in the Luoyangjiang River Estuary.

Oysters are a group of economically important bivalves in China, with estuaries serving as one of their primary cultivation areas. However, heavy metal pollution in these estuarine environments poses a potential threat to aquaculture by leading to the accumulation of heavy metals in farmed oysters, which could impact their safety and marketability. This study was conducted in the aquaculture area of the Luoyangjiang River estuary, where eight sampling sites were selected. Water, sediment, and oysters categorized by shell length were collected from each site. The concentrations of heavy metals (Ag, As, Cd, Cr, Cu, Ni, Pb, and Zn) were determined in both the environmental samples and oyster tissues. Additionally, multiplex species-specific PCR was used to identify oyster species. The results showed significant variations in dissolved-phase and suspended particulate matter (SPM) metal concentrations across different sampling sites, while sediment metal concentrations were more consistent but similar to those in SPM. The large oysters were comprised of 50% Magallana angulata and 50% Magallana gigas, while small oysters were identified as Magallana sikamea. The Cd, Cu, Pb, and Zn levels in both size groups of oysters exceeded data from previous studies, indicating contamination in the estuary. The observed differences in heavy metal concentrations between large and small oysters primarily reflect species-specific variability in metal accumulation, which may also be influenced by factors such as growth and exposure duration. Furthermore, the lack of significant correlation between metal concentrations in environmental media and oysters suggests that oysters may be exposed to multiple sources of metal contamination.

Transcriptome Analysis Reveals the Effect of Oyster Mushroom Spherical Virus Infection in Pleurotus ostreatus.

Oyster mushroom spherical virus (OMSV) is a mycovirus that inhibits mycelial growth, induces malformation symptoms, and decreases the yield of fruiting bodies in Pleurotus ostreatus. However, the pathogenic mechanism of OMSV infection in P. ostreatus is poorly understood. In this study, RNA sequencing (RNA-seq) was conducted, identifying 354 differentially expressed genes (DEGs) in the mycelium of P. ostreatus during OMSV infection. Verifying the RNA-seq data through quantitative real-time polymerase chain reaction on 15 DEGs confirmed the consistency of gene expression trends. Both Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses highlighted the pivotal role of primary metabolic pathways in OMSV infection. Additionally, significant changes were noted in the gene expression levels of carbohydrate-active enzymes (CAZymes), which are crucial for providing the carbohydrates needed for fungal growth, development, and reproduction by degrading renewable lignocellulose. The activities of carboxymethyl cellulase, laccase, and amylase decreased, whereas chitinase activity increased, suggesting a potential mechanism by which OMSV influenced mycelial growth through modulating CAZyme activities. Therefore, this study provided insights into the pathogenic mechanisms triggered by OMSV in P. ostreatus.

Marine thermal fluctuation induced gluconeogenesis by the transcriptional regulation of CgCREBL2 in Pacific oysters.

Marine thermal fluctuation profoundly influences energy metabolism, physiology, and survival of marine life. In the present study, short-term and long-term high-temperature stresses were found to affect gluconeogenesis by inhibiting PEPCK activity in the Pacific oyster (Crassostrea gigas), which is a globally distributed species that encounters significant marine thermal fluctuations in intertidal zones worldwide. CgCREBL2, a key molecule in the regulation of gluconeogenesis, plays a critical role in the transcriptional regulation of PEPCK in gluconeogenesis against high-temperature stress. CgCREBL2 was able to increase the transcription of CgPEPCK by either binding the promoter of CgPEPCK gene or activating CgPGC-1α and CgHNF-4α after short-term (6 h) high-temperature stress, while only by binding CgPEPCK after long-term (60 h) high-temperature stress. These findings will further our understanding of the effect of marine thermal fluctuation on energy metabolism on marine organisms.

One becomes three: An integrative morphological and molecular analysis of the windowpane oyster Placuna (Bivalvia: Pectinida) reveals new species.

For decades, many marine animals have been considered to exhibit cosmopolitan or transoceanic distribution. This situation is prevalent in Asia, where many species were collected and named by American or European experts in the 1700s to early 1900s. Using the windowpane oysters Placuna-a small genus of bivalves with five recognized species-we show that careful analysis is required to reassess the validity of these species. Currently, only two species of Placuna (P. placenta and P. ephippium) widely reported in the Indo-Pacific region have been recorded from Chinese coastal waters. Here, we described two new species of Placuna from China. Placuna vitream sp. nov. can be distinguished from P. placenta by its larger ridge angle. Phylogenetic analysis using five gene fragments fully supported that P. vitream sp. nov. is a sister to the specimen from Singapore identified as P. placenta and more distant from other Placuna species with available molecular data. Besides, based on subfossil shells, we describe Placuna aestuaria sp. nov. that differs from its congeneric species by its broad hinge, medium ridge angle, and nearly straight ridges. Finally, we suggest a combination of hinge structure and ridge angle that can be used for identifying Placuna species and preparing a key to this genus. Our findings of two new species expand the diversity of Placuna and prompt reassessment of the many presumably widely distributed marine species in Asia.

Effects of tire particles and associated-chemicals on the Pacific oyster (Magallana gigas) physiology, reproduction and next-generation.

By 2040, tire particles (TP) are expected to dominate marine plastic contamination, raising concerns about their effects on marine animals. This study employed a multidisciplinary and multigenerational approach on the Pacific oyster Magallana gigas to investigate the effects of TP and their leachates (LEA). Effects were analyzed at the individual scale, from cellular, molecular, and microbiota changes to reproductive outputs and offspring performance. Microbiota characterization revealed potential dysbiosis in oysters treated with high concentration of both TP and LEA. RNA-seq analyses highlighted the activation of energy metabolism and stress responses in the LEA treatment. Additionally, transcriptional changes in oocytes and the reduction of motile spermatozoa suggested potential effects on gamete quality. Notably, possible oyster resilience was pointed out by the lack of significant ecophysiological modifications in adults and impacts on the growth and reproductive outputs of the offspring. Overall, the implications of the observed oyster resilience under our experimental setting are discussed in relation to available toxicity data and within a comprehensive view of coastal ecosystems, where a higher diversity of plastic/rubber materials and harsher environmental conditions occur.

Combined copper isotope and elemental signatures in bivalves and sediments from the Korean coast: Applicability for monitoring anthropogenic contamination.

This study investigates the applicability of elemental and Cu isotope compositions in sediments and bivalves from the Korean coast to monitor anthropogenic Cu contamination. Sediments with high Cu (>64.4 mg/kg) and/or moderate enrichment levels (EFCu) exhibit homogenous δ65CuAE647 values (-0.12 to +0.16 ‰), suggesting similar anthropogenic Cu fingerprints along the Korean coast. Sediments with Cu concentrations near natural background levels (< 20.6 mg/kg) display large isotopic variability (Δ65Cumax-mim: ~0.8 ‰), encompassing those from sediments under anthropic influences. We hypothesize that Cu isotopic compositions of Korean geology are heterogeneous, therefore, natural end-members of source mixing models should be established locally at small scales. Cu concentrations in Oysters correlate with sediments, and their isotopic compositions are more suitable for monitoring Cu contamination, while mussel's regulatory mechanisms seem to affect source records. The current Cu isotope data will help to detect shifts attributable to anthropic contamination in future biomonitoring.

Lactiplantibacillus plantarum 299V fermented in microcapsules shows enhanced stability and could improve the microbial quality and safety of oysters through bioaccumulation.

In this study, microcapsules of Lactiplantibacillus plantarum 299V were prepared using an emulsification/internal gelation technique. Loads of the probiotics were condensed to 9.86 ± 0.13 log CFU/g after 24 h fermentation of the microcapsules. Physical characterization revealed that L. plantarum 299V cells were uniformly distributed within the core of the microcapsules, with a mean diameter of 109.81 ± 0.39 µm and a span value of 0.36 ± 0.00, which were comparable to those of the unfermented microcapsules (p > 0.05). The viability of L. plantarum 299V in the fermented microcapsules was 2.08 ± 0.15 log higher than that of free cells at the end of 5 h simulated gastrointestinal digestion (p < 0.05). Oysters were able to accumulate the fermented microcapsules through filter feeding, resulting in a load of probiotics exceeding 6.00 log CFU/g. The presence of L. plantarum 299V-carrying microcapsules in oyster tissues significantly suppressed spoilage-causing bacteria during 11 days refrigeration storage, suggested by the tested parameters, including total psychrotrophic bacteria, H2S-producing bacteria, and Pseudomonas spp. (p < 0.05). Pathogenic bacteria, including Vibrio parahaemolyticus and Salmonella enterica artificially introduced into oysters, were also significantly suppressed by over 1.00-log within 4 days compared to control samples (p < 0.05). In summary, oysters bioaccumulated with fermented L. plantarum 299V-carrying microcapsules, justified a novel probiotic-carrying product to exsert the health-promoting effect of probiotics. This solution could also enhance the microbial quality and safety of oysters during storage.

Effect of fortified calcium compounds from oyster shell on the quality of tapioca pearls.

This study aimed to determine the effect of calcium fortification from dried oyster shells (DOS) and calcined oyster shells (COS) at concentrations of 2, 4 and 6 %(w/w) on physical and chemical properties of tapioca pearls. The results showed that the optimal cooking time of TP-COS decreased compared to TP-DOS and TP (control). The TP-DOS and TP-COS exhibited a remaining calcium content ranging from 8.39 to 41.03 mg/g. During seven days of refrigerated storage, TP-COS showed delayed hardness along with decreases in both the enthalpy of gelatinization and retrogradation. The functional groups observed in TP-DOS and TP-COS showed varying intensities compared to TP. Morphology images depicted the distribution of DOS and COS within tapioca pearls, revealing that TP-DOS and TP-COS possessed a denser and more compact structure. The results suggest that COS fortification could improve the nutritional value and delay the change in the texture of tapioca pearls after storage.

Industrial manufacturing method and characterization of Ayurvedic marine drugs: mother pearl, cowry, coral and pearl.

Introduction: Ayurvedic marine drugs derived from mollusc shells and coral are regularly used by Ayurvedic physicians to treat several disease conditions like acid peptic disease, irritable bowel syndrome, osteoporosis, etc. However, standard operating procedures for manufacturing these drugs and their complete characterization have not been published in the Ayurvedic Formulary and Ayurvedic Pharmacopeia of India to date. Methods: Present study describes the traditional manufacturing process and thorough characterization using classical and advanced analytical tools. The raw materials characters, in-process parameters, and finished product specifications have been elaborated to develop monographs. Especially, the identity and purity of raw coral and pearl were checked by Raman Spectroscopy and Energy Dispersive X-ray Fluorescence analysis. Results: In the finished product analysis, the X-Ray Diffraction study revealed that incineration after trituration with Aloe barbadensis leaf pulp or rose water converted the aragonite phase of calcium carbonate into calcite phase in mother pearl, cowry, and pearl while the calcite form of raw coral was retained. The prominent bands around 1390, 870, and 712 cm-1 detected by Fourier Transform-Infrared Spectroscopy and mass loss between 39-44% (w/w) revealed by thermogravimetric analysis confirmed the carbonate form of these calcium-based drugs. The finished products were very fine grayish-white powders constituted by irregularly shaped nano-micro particulate calcium carbonate exhibiting particle size between 600 nm (D10 value) to 1.2 µm (D90 value). Conclusion: The quality control and assurance achieved in this study may be further utilized by the pharmaceutical industries to manufacture quality marine drugs and conduct efficacy studies.

Characterization of water microbiota and their relationship with resident oysters during an oyster mortality event.

Microorganisms are vital for the health of marine invertebrates, and their assembly is driven by both deterministic and stochastic factors that regulate residents (innate to the host) and transients (from ambient water). However, the role of water microbiota and the significance of deterministic and stochastic processes in aquatic hosts facing mortality threats are largely unknown. This study examines the shifts in water microbiota during an oyster mortality event using amplicon sequencing and compared with those of resident oysters to disentangle the balance of the deterministic and stochastic factors involved. Water temperature and dissolved oxygen significantly shape the microbial community with a distinct monthly pattern, and Cyanobacteria blooms might exacerbate oyster mortality. The comparative analysis of microbial communities in oysters and water revealed that ≤ 21% of the genera were shared between oysters and water, implying that water microbiota cannot easily transfer into oysters. Furthermore, these shared genera had different functions, with oysters more involved in promoting host digestion and nutrient acquisition and water bacteria enriched more in functions promoting their own growth and survival. These findings illustrate that oysters may possess specific selection or barrier mechanisms that permit a small percentage of transients, controlled by stochastic factors and having a minimal effect on oyster mortality, to enter, whereas the majority of oyster microbiota are residents governed by deterministic factors. Consequently, oysters exhibit some plasticity in their symbiotic microbiota, enabling them to maintain microbial homeostasis and adapt to complex microbial surroundings. This may be a shared mechanism among marine invertebrates for survival in complex marine environments.IMPORTANCEPacific oysters are widely cultured and play vital ecological roles. However, the summer mortality hinders sustainable oyster farming. Untangling causative mechanisms of oyster mortality is a complex task due to the intricate "interactome" involving environmental factors, hosts, and pathogens. Interactions between hosts and microorganisms offer an ideal avenue for investigating the truth. We systematically investigated the microbial community in water and resident oysters during a summer mortality event and proposed that the assembly of oyster microbiota is primarily governed by deterministic processes independent of mortality. Pathogens mainly originate from resident members of the oyster microbiota, with a limited influence from the microbial community in the water. Additionally, environmental degraders, such as Cyanobacteria blooms, cannot be overlooked as a contributing factor of oyster mortality. This study evaluated the weight of deterministic and stochastic factors in microbial assembly during an oyster mortality event and greatly broadened our understanding of the "interactome" through the interaction between oysters and water in microbiota.

The core microbiome of cultured Pacific oyster spat is affected by age but not mortality.

The Pacific oyster is the most widely cultured shellfish worldwide, but production has been affected by mortality events, including in hatcheries that supply the seed for growers. Several pathogens cause disease in oysters, but in many cases, mortality events cannot be attributed to a single agent and appear to be multifactorial, involving environmental variables and microbial interactions. As an organism's microbiome can provide resilience against pathogens and environmental stressors, we investigated the microbiomes in cohorts of freshly settled oyster spat, some of which experienced notable mortality. Deep sequencing of 16S rRNA gene fragments did not show a significant difference among the microbiomes of cohorts experiencing different mortality levels, but revealed a characteristic core microbiome comprising 74 taxa. Irrespective of mortality, the relative abundance of taxa in the core microbiomes changed significantly as the spat aged, yet remained distinct from the microbial community in the surrounding water. The core microbiome was dominated by bacteria in the families Rhodobacteraceae, Nitrosomonadaceae, Flavobacteriaceae, Pirellulaeceae, and Saprospiraceae. Within these families, 14 taxa designated as the "Hard-Core Microbiome" were indicative of changes in the core microbiome as the spat aged. The variability in diversity and richness of the core taxa decreased with age, implying niche occupation. As well, there was exchange of microbes with surrounding water during development of the core microbiome. The shift in the core microbiome demonstrates the dynamic nature of the microbiome as oyster spat age.IMPORTANCEThe Pacific oyster (Magallana gigas, also known as Crassostrea gigas) is the most widely cultivated shellfish and is important to the economy of many coastal communities. However, high mortality of spat during the first few days following metamorphosis can affect the seed supply to oyster growers. Here, we show that the microbiome composition of recently settled oyster spat experiencing low or high mortality was not significantly different. Instead, development of the core microbiome was associated with spat aging and was partially driven by dispersal through the water. These findings imply the importance of early-stage rearing conditions for spat microbiome development in aquaculture facilities. Furthermore, shellfish growers could gain information about the developmental state of the oyster spat microbiome by assessing key taxa. Additionally, the study provides a baseline microbiome for future hypothesis testing and potential probiotic applications on developing spat.

The Discovery and Characterization of a Potent DPP-IV Inhibitory Peptide from Oysters for the Treatment of Type 2 Diabetes Based on Computational and Experimental Studies.

The inhibition of dipeptidyl peptidase-IV (DPP-IV) is a promising approach for regulating the blood glucose levels in patients with type 2 diabetes (T2D). Oysters, rich in functional peptides, contain peptides capable of inhibiting DPP-IV activity. This study aims to identify the hypoglycemic peptides from oysters and investigate their potential anti-T2D targets and mechanisms. This research utilized virtual screening for the peptide selection, followed by in vitro DPP-IV activity assays to validate the chosen peptide. Network pharmacology was employed to identify the potential targets, GO terms, and KEGG pathways. Molecular docking and molecular dynamics simulations were used to provide virtual confirmation. The virtual screening identified LRGFGNPPT as the most promising peptide among the screened oyster peptides. The in vitro studies confirmed its inhibitory effect on DPP-IV activity. Network pharmacology revealed that LRGFGNPPT exerts an anti-T2D effect through multiple targets and signaling pathways. The key hub targets are AKT1, ACE, and REN. Additionally, the molecular docking results showed that LRGFGNPPT exhibited a strong binding affinity with targets like AKT1, ACE, and REN, which was further confirmed by the molecular dynamics simulations showcasing a stable peptide-target interaction. This study highlights the potential of LRGFGNPPT as a natural anti-T2D peptide, providing valuable insights for potential future pharmaceutical or dietary interventions in T2D management.

Laboratory Replication of Ostreid Herpes Virus (OsHV-1) Using Pacific Oyster Tissue Explants.

Pacific oysters (Crassostrea or Magallana gigas) are one of the most economically important aquaculture species globally. Over the past two decades, ostreid herpesvirus (OsHV-1) has become a major pathogen of cultured Pacific oysters, resulting in widespread mortality with a global distribution. Experimental use of OsHV-1 is challenging for many reasons, including both complexity of host-pathogen dynamics and a lack of functioning model systems. The goal of this study was to improve the tools available for working with OsHV-1 in both whole animals and in tissue explants established from oysters maintained in controlled laboratory conditions. Tissue explants were taken from oysters originating from two different sources that have different levels of mortality in experimental OsHV-1 infections and were exposed to OsHV-1. A whole-animal infection experiment was run concurrently as a comparison. Quantitative PCR and electron microscopy were used to confirm that the explants were capable of replicating OsHV-1. Furthermore, the quantitative PCR results suggest that the source of the oysters was significant in determining the outcome of infection in the explants, supporting the validity of the explant model for OsHV-1 infection. This tissue explant approach for studying OsHV-1 allows for the control of confounding factors in the disease outcome that is not possible in whole-animal experiments, providing a new tool for the study of OsHV-1 in Pacific oysters.

Effects of acetylated distarch phosphate on the physicochemical characteristics and stability of the oyster sauce system.

In this study, the effect of different acetylated distarch phosphate (ADSP) ratios (0, 1%, 2%, 3%, 4%, 5%) on the physicochemical characteristics and stability of the oyster sauce (OS) system was investigated. The texture, water state, interactions, rheological properties, microstructure, and stability of OS samples were analyzed through the texture analyser, low-field nuclear magnetic resonance (LF-NMR), particle diameter and zeta potential, fourier-transform infrared spectroscopy (FTIR), rheometer, and microscopes. The results revealed that the addition of ADSP improved the firmness, consistency, cohesiveness, and water-holding capacity of OS. Moreover, ADSP reduced the average particle size and zeta potential of OS, indicating that electrostatic and steric stabilization existed in the ADSP-OS system. The addition of ADSP enhanced the hydrogen bonding and decreased water mobility for OS system, processing a more continuous and smooth structure. All ADSP-OS samples were typical non-Newtonian fluids with shear-thinning characteristics. In addition, the non-significant instability index changes of ADSP-OS over the whole storage period confirmed the excellent long-term stabilization capability of OS prepared with ADSP. This study provides a theoretical basis for starch-based sauce products and contributes to the development of sauce products.