Search Results (144)

In vitro 3D cell culture systems provide a physiologically relevant microenvironment that mimics native tissue architecture. However, establishing functional 3D testicular aggregates in teleosts remains challenging. In this study, we established a novel 3D co-culture aggregate system for olive flounder (Paralichthys olivaceus) primary testicular cells by incorporating the established olive flounder testicular cell (OFT) line. Primary testicular cells alone failed to form 3D aggregates within the first 24 h in ultra-low attachment plates. However, co-culturing with OFT cells rapidly initiated 3D aggregate assembly within 24 h. Furthermore, supplementation with a cocktail of sex hormones and growth factors maintained high cell viability without cytotoxic effects. Notably, quantitative real-time PCR analysis revealed that hormone and growth factor supplementation significantly upregulated the transcript levels of both plzf (2.15-fold) and scp3 (2.34-fold). These results demonstrate that the OFT cell line is essential for facilitating the assembly and incorporation of primary testicular cells into 3D aggregates, while sex hormones and growth factors promote spermatogonial stem cell maintenance and meiotic progression within the aggregates. Overall, this 3D co-culture platform serves as a valuable in vitro tool for fish spermatogonial stem cell research and reproductive biotechnology in aquaculture. Full article

Copepods are widely recognized as biologically superior live prey for many marine fish larvae, yet their routine large-scale production remains a major bottleneck in aquaculture. Within this context, the harpacticoid genus Tigriopus has attracted increasing attention because it combines broad environmental tolerance, ease of culture, and promising nutritional and biotechnological value. This review critically examines the current state of knowledge on the genus Tigriopus, with particular emphasis on its aquaculture relevance, while integrating the biological, ecological and ecotoxicological framework needed to interpret the specific case of the Mediterranean species T. fulvus. The available literature shows that in aquaculture, the potential of this copepod genus is supported by complementary evidence across species. T. californicus currently provides the strongest proof of concept for pilot-scale biomass production and biochemical valorization, particularly as a source of omega-3- and astaxanthin-rich biomass. T. japonicus contributes most clearly to culture optimization and live-feed application, especially with respect to feeding performance and stocking-density effects. Tigriopus fulvus, in contrast, remains an earlier-stage but credible Mediterranean candidate, showing promising diet-dependent naupliar production and survival, although its culture technology is still underdeveloped. Overall, Tigriopus should be regarded as a genus of growing relevance for aquaculture, not only as live prey but also as a potential source of functional biomass. Future progress will depend on improved mass-culture methods, feeding optimization, harvesting efficiency, and a comparative species-level framework linking biological traits to specific aquaculture applications. Full article

Transgenesis and gene editing offer a promising approach for more efficient and sustainable aquaculture by generating high-performance fish to enhance global food security. This article provides a comprehensive review of the history, current status, and future perspectives of employing transgenesis and gene-editing technologies to improve fish production and welfare, focusing on catfishes, which represent a diverse group of economically important fish. We discussed the application of various genetic technologies, including gene transfer (transgenesis) and gene editing, to boost fish economic traits and achieve genetic confinement. We also reviewed the progress on integrating transgenesis and gene-editing techniques for multiple gene editing, an approach that can speed up and make the genetic modification of fish more efficient. This review also highlights several research gaps in the current literature on gene transfer and gene editing in catfishes. Specifically, it provides directions for future catfish research, including the employment of transcriptomics in phenotypic assessment of transgenic and gene-edited fish, addressing compensatory mechanisms when selecting the gene-editing targets, and accounting for gene-environment and gene-nutrition interactions. It also highlights the application of advanced gene-editing tools, integration of genomic selection and artificial intelligence with gene editing, transparent public education about the benefits and risks of genetic biotechnology, and the development of effective reproductive confinement strategies. Full article

The transition to a circular bioeconomy is increasingly recognised as a critical pathway for achieving climate neutrality and resource use efficiency in Ireland. However, this transition is highly dependent on the availability of a skilled workforce capable of operating across interconnected bio-based sectors. Ireland’s National Bioeconomy Action Plan recognises the critical role that skills and knowledge will play in this transition. This study develops a comprehensive taxonomy of skills required to support the transition to a circular bioeconomy, with a specific focus on key Irish primary bioeconomy sectors (agriculture, forestry, fishery and aquaculture) and traditional industries (food processing, wood, textiles, and construction). A qualitative systematic literature review was conducted following the PRISMA 2020 guidelines. Peer-reviewed articles were retrieved from the Web of Science and Scopus databases and complemented with relevant Irish and European grey literature. A total of 96 publications were analysed using thematic analysis to identify and synthesise sector-specific and cross-sectoral competencies. The taxonomy organises circular bioeconomy skills into five overarching competence domains (systems-thinking, sustainability, circularity and bioeconomy/biotechnology, and digital skills). Findings reveal that while each sector has unique skills, a set of shared skills is consistently critical across all sectors. The identified competencies were subsequently organised into a structured taxonomy and mapped to Ireland’s National Framework of Qualifications (NFQ), establishing progressive proficiency levels from awareness (NFQ 5–6) through practitioner (NFQ 7–8) to expert (NFQ 9–10). This competency progression framework represents the principal contribution of the study, translating the taxonomy into a practical tool for curriculum development, workforce planning, professional development, and policy implementation. Full article

The dramatic rise in global aquaculture has brought renewed focus on filamentous fungi impacting fish health and aquafeeds. The fungal genus Aspergillus has a Janus-like role in aquaculture. On the pathogenic side, opportunistic pathogens like A. flavus, A. niger and A. fumigatus cause outbreaks of aspergillosis, with granulomatous lesions and significant mortality, especially in fish with impaired immunity and/or poor environmental conditions. Toxigenic strains of A. flavus and A. parasiticus also contaminate aquafeeds with aflatoxins, some of the most toxic natural hepatotoxins and carcinogens, which have been shown to affect growth, immunity and aflatoxin residues in edible fish fillets. On the positive side, non-toxigenic strains of A. niger, A. oryzae and A. awamori are increasingly used as fungal probiotics, solid-state fermenters to upgrade plant protein feed supplements, and as sources of industrially useful hydrolytic enzymes, secondary metabolites and antifungal compounds. Synthesizing evidence from over 90 peer-reviewed studies, this narrative review elucidates how species, strain, and rearing context jointly determine whether Aspergillus behaves as a pathogen or as a functional additive. We highlight knowledge gaps, offer an interpretative model and suggest practical strategies to limit risks and leverage the biotechnological uses of Aspergillus for sustainable aquaculture. The novelty of this review lies in integrating, within a single finfish-focused framework, the three usually separate faces of Aspergillus—pathogen, aflatoxin producer, and functional feed additive—and in translating this dual nature into practical, strain-level guidance for aquaculture. Full article

Background/Objectives: Polymethyl methacrylate (PMMA) is widely used in medical and dental applications because of its favorable mechanical properties and ease of processing. However, its clinical performance is limited by low surface hardness, hydrophobicity, and susceptibility to microbial colonization and biofilm formation. This study aimed to investigate the effects of amorphous titanium dioxide (TiO₂) nanolayers deposited by atomic layer deposition (ALD) on the surface morphology and antibacterial properties of PMMA-based materials. Methods: Amorphous TiO₂ coatings were deposited on bone cement PMMA and dental PMMA substrates using ALD with TiCl₄ and H₂O precursors at 80 °C. The low deposition temperature enabled the conformal of thermally sensitive polymer substrates. Surface characterization was performed using atomic force microscopy (AFM) and scanning electron microscopy (SEM) to evaluate coating morphology and nanoscale topography. Antibacterial activity was assessed against S. aureus and P. aeruginosa through planktonic growth and biofilm formation assays, with additional evaluation of ultraviolet (UV) activation and surface polishing. Results: AFM analysis revealed that amorphous TiO₂ coating on standardly laboratory practice-polished PMMA increased the arithmetical mean roughness (Ra) from 1.82 nm to 14.60 nm, and maximum height (Rmax) from 36.20 nm to 298.00 nm. Polishing before coating significantly increased surface roughness and height variation, resulting in complex micro- and nanotopography. Microbiological analyses demonstrated variable antibacterial effects depending on bacterial species and surface characteristics. Comparison of planktonic growth, biofilm formation and OD590 ratio showed that amorphous TiO2 coating on polished PMMA reduced biofilm formation and planktonic growth in P. aeruginosa with a decreased OD ratio, while S. aureus biofilm formation was reduced. S. aureus had a consistently higher OD590 than P. aeruginosa. UV treatment alone did not produce consistent antibacterial enhancement. Conclusions: The study findings suggest that the surface topography had a greater role than UV treatment in determining bacterial adhesion. Surface roughness was strongly associated with S. aureus adhesion., whereas P. aeruginosa showed minimal response to the tested surface modifications. These findings suggest that TiO₂ coating after standard polishing alone may not provide consistent antibacterial activity under the tested conditions and point to the importance of nanoscale surface design in developing antimicrobial polymer biomaterials. Full article

Cryopreservation of semen is an important interdisciplinary field at the intersection of reproductive biotechnology and cryobiology, and holds significant value for the genetic rescue of endangered species, long-term preservation of germplasm resources, and management of reproduction in livestock and aquaculture. Although this technology is relatively well established in fish and terrestrial mammals, it still faces numerous challenges in marine mammals, particularly cetaceans. The Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis), a rare and endemic freshwater porpoise of China, remains at an early stage of research regarding semen cryopreservation, and there is an urgent need to develop a technical system tailored to its unique physiological characteristics. Literature was searched in PubMed, Web of Science, and CNKI from database inception to May 2025. This structured narrative review was based on 77 core publications, including eight original studies on cetacean semen cryopreservation. This structured narrative review synthesizes evidence from cetacean semen cryopreservation research, with particular emphasis on technical insights from the bottlenose dolphin (Tursiops truncatus), Pacific white-sided dolphin (Lagenorhynchus obliquidens), killer whale (Orcinus orca), and beluga (Delphinapterus leucas). Additionally, it incorporates advances in extender formulations and cryoprotectants from studies on other species to summarize key technical parameters suitable for the cryopreservation of Yangtze finless porpoise semen, aiming to provide a theoretical basis and practical framework for establishing an efficient and safe cryopreservation system for this species. Full article

Marine algae are emerging as important biological resources for the discovery and development of bioactive compounds with applications across food, pharmaceutical, cosmetic, agricultural, aquaculture, environmental, and biotechnological systems. This review critically synthesizes current knowledge on macroalgae and microalgae as sources of sulfated polysaccharides, carotenoids, phenolic compounds, proteins, peptides, vitamins, mycosporine-like amino acids, and polyunsaturated fatty acids. Emphasis is placed on the relationship between algal source, cultivation conditions, compound structure, extraction strategy, formulation, and biological activity. Key mechanisms of action are discussed, including antioxidant defense, modulation of inflammatory signaling, inhibition of metabolic enzymes, antimicrobial and antiviral activity, interactions with the gut microbiota, and regulation of cell-cycle-related pathways. Recent progress in biotechnological production, green extraction, purification, analytical characterization, bioaccessibility, bioavailability, and delivery systems is evaluated in the context of real product development. The review further highlights the use of algal bioactives in functional foods, nutraceuticals, pharmaceuticals, cosmeceuticals, aquafeeds, crop biostimulants, and environmental remediation. Current limitations, including biomass variability, compound instability, limited human validation, regulatory complexity, safety concerns, and scale-up costs, are also addressed. Overall, marine algae provide a sustainable and multifunctional platform for developing bioactive products when discovery, processing, validation, and commercialization are integrated. Full article

Background/Objectives: Course-based Undergraduate Research Experiences (CUREs) represent a form of student crowdsourcing in which individuals perform authentic discovery-based research in a class setting with interest to outside stakeholders. Here, the renowned Tiny Earth (TE) CURE is being utilized to teach microbiology and perform natural product discovery research by students in the course. Methods: In our TE CURE, students collect soil samples from their hometown and characterize bacteria that can inhibit plant and animal pathogens. This unique growing collection of isolates from across Ohio has provided opportunities to facilitate drug discovery and establish biotechnology collaborations. Results: In this study, we describe two outcomes using our environmental strain collection that initiated biotechnology collaborations and identified bacterial candidates for drug discovery. Results from one project led to a partnership with an aquaculture company. A novel biosynthetic gene cluster involved in antagonistic activity was identified, whose product inhibits Aeromonas pathogens, which cause disease in freshwater fish. The other project involves a collaboration with a global commercial cleaning and equipment company to identify lipase activity among Bacillus strains for its potential use in bioremediation. Conclusions: The unique strain collection generated by students in the CURE led to collaboration with biotechnology companies, which contributed to natural product discovery of an antimicrobial product and active enzymatic activity, all of which benefit education and scientific discovery. Full article

Marine macroalgae are widely distributed renewable resources that offer substantial economic and environmental benefits. This review comprehensively examines seaweeds from the phyla Chlorophyta, Heterokontophyta, and Rhodophyta, highlighting key advances and persistent challenges. Global seaweed production is highly concentrated: Asia accounts for 97% of the total, with China as the dominant producer. These seaweeds synthesize a diverse array of bioactive compounds, including sulfated polysaccharides, phlorotannins, terpenoids, proteins, peptides, polyunsaturated fatty acids, and pigments. Notably, brown algae represent the richest source of both phlorotannins and polyunsaturated fatty acids. To recover these valuable compounds efficiently, a range of advanced green extraction techniques have been developed, such as enzyme-assisted, microwave-assisted, ultrasound-assisted, and supercritical fluid extraction, along with natural deep eutectic solvents. These methods consistently outperform conventional approaches in terms of yield, extraction time, and environmental sustainability. The isolated compounds exhibit a broad spectrum of validated pharmacological activities, including immunomodulatory, anti-inflammatory, anti-diabetic, neuroprotective, antitumor, and antiviral effects. Consequently, they have found diverse applications in functional foods, biomedicine, cosmetics, agriculture, aquaculture, and environmental protection. Despite this promise, critical challenges remain in elucidating structure–activity relationships, developing scalable and sustainable extraction protocols, and advancing clinical translation. Future research should prioritize the discovery of novel marine bioactives, the enzymatic production of oligosaccharides, efficient purification of algal proteins and peptides, and the scaling-up of industrial processes to fully realize the pharmaceutical and biotechnological potential of marine macroalgae. Full article

Microalgae are valuable biotechnological resources due to their high productivity and their capacity to synthesize compounds with nutritional and antioxidant functions. However, in the Santa Elena Peninsula (Ecuador), their use in aquaculture is limited to commercial strains. In this study, native microalgae were isolated and evaluated for their nutritional value in aquaculture. Samples were collected at five coastal sites, cultivated under controlled conditions, and characterized using optical microscopy and SEM, identified at the molecular level through the 28S rRNA gene, and their biochemical profiles were analyzed, including carotenoid quantification. The isolates were identified as PM-UPSE-006 (Tetradesmus obliquus), PM-UPSE-007 (Conticribra weissflogii), PM-UPSE-016 (Halamphora coffeiformis), PM018 (Dunaliella sp.), and PM-UPSE-022 (Chlorella vulgaris), with T. obliquus and H. coffeiformis being recorded for the first time in the peninsula. The highest growth rates were observed in T. obliquus, Dunaliella sp., and C. vulgaris, while Dunaliella sp. and C. vulgaris stood out for their protein content (57.28% DM and 55.37% DM), T. obliquus for carbohydrates (40.5% DM), and H. coffeiformis, Dunaliella sp., and C. vulgaris for carotenoids (0.53–1.60% DM). These results demonstrate their ex situ adaptability, competitive growth, and noteworthy biochemical profiles, establishing them as promising biotechnological resources for sustainable aquaculture. Full article

With the rapid development of global aquaculture, the frequent occurrence of fish diseases has had a serious impact on the efficiency of aquaculture and the ecological environment. Antimicrobial peptides, as a kind of natural immune active substance existing in organisms, participate in innate immunity and adaptive immunity. Due to their extensive antibacterial properties and low toxicity, they have gradually become a hot topic in scientific research. This article reviews the classification, tissue distribution, mechanism of action, extraction, and synthesis techniques of antimicrobial peptides (AMPs) derived from fish, as well as their applications in disease prevention in aquaculture, product preservation, and antibiotic substitution. Although antimicrobial peptides are expected to become alternatives to antibiotics, challenges such as environmental stability, production costs, and regulatory frameworks remain to be addressed. This article holds that antimicrobial peptides derived from fish are a feasible strategy for sustainable aquaculture. The future development direction lies in biotechnology-driven optimization, carrier innovation, and combined application with traditional antibiotics. Full article

This study evaluated the efficacy of ammonia-nitrogen-reducing biofilms (aquatic nitrifying bacteria biofilm media, a fixed-bed biofilm capable of simultaneous nitrification and denitrification) in mitigating water quality deterioration and transport-induced physiological stress in live-transported Crucian carp (Carassius auratus). In a simulated bag transport system, the application of the biofilm significantly decreased ammonia-nitrogen concentrations through enhanced nitrification, stabilized pH and dissolved oxygen dynamics, and suppressed nitrite accumulation. Correspondingly, biofilm-treated fish exhibited significantly reduced systemic stress responses, as evidenced by reduced serum cortisol, glucose, and lactate dehydrogenase concentrations, along with diminished histopathological changes in gill and liver tissues and preserved muscle fiber integrity. Regarding post-transport muscle quality, biofilm treatment delayed glycogen catabolism and lactate accumulation, maintained elevated muscle pH and water-holding capacity, reduced shear force decline, decelerated ATP hydrolysis and freshness degradation (K-value), and simultaneously suppressed lipid peroxidation and myonuclear apoptosis. These findings demonstrate that ammonia-nitrogen-reducing biofilms represent a viable biotechnological approach for maintaining water quality, mitigating stress-induced physiological disturbances, and preserving flesh quality during live fish transportation. This approach has significant potential for improving post-harvest outcomes in aquaculture logistics. Full article

Functional seafoods derived from marine organisms, including fish, shellfish and algae, are gaining increasing attention due to their high content of bioactive compounds, such as omega-3 fatty acids, peptides, polysaccharides and antioxidants, which provide health benefits beyond basic nutrition. These marine-derived compounds exhibit a wide range of biological activities and have been investigated for their potential roles in the prevention and management of chronic diseases, including cardiovascular, neurodegenerative, cancer and gastrointestinal disorders. Their effects are largely mediated through anti-inflammatory, antioxidant and immunomodulatory mechanisms. Advances in biotechnology, including genetic engineering and improved extraction of bioactive compounds, have enhanced the nutritional quality and pharmacological relevance of functional seafoods. At the same time, sustainable aquaculture practices are being developed to reduce environmental impacts. Nevertheless, challenges such as regulatory inconsistencies, scalability issues and limited understanding of bioavailability and long-term effects still persist. These constraints should be considered when interpreting mechanistic and efficacy findings presented across different study designs and exposure conditions. Future perspectives highlight innovations in precision aquaculture, waste valorisation and traceability as key strategies to improve sustainability and strengthen consumer trust. This review summarizes current knowledge on functional seafoods, with emphasis on pharmacological mechanisms, clinical applications and the need for interdisciplinary research to optimize their health benefits and commercial potential. Full article

This pioneering study investigates bacteria isolated from marine pelagic fish, fishing vessels, and gear surfaces, focusing on the variability in biofilm formation across different substrates, media, and cultivation conditions. Bacteria from fish intestines, skin, and gills, including spoilage organisms and potential fish and human pathogens, can contaminate vessel surfaces, gear, and containers and may act as microbial reservoirs and transmission vectors. In this study, biofilm formation was evaluated at air–liquid interfaces and on submerged plastic, metal, and glass surfaces under various incubation temperatures and media. Vibrio spp. were isolated both from fishing nets and fish gills, particularly Vibrio alginolyticus, V. gigantis, and V. pelagius. Although V. harveyi was examined as a representative vibrio, it did not form a biofilm on polypropylene. Photobacterium damselae subsp. damselae, Pseudomonas fragi, P. gessardii, Psychrobacter spp., and Rothia endophytica showed a strong affinity for stainless steel. Overall adhesion regardless of media type was highest for P. gessardii, followed by P. damselae and Aeromonas veronii, which adhered strongly to steel, glass, and polypropylene; however, only P. gessardii also adhered well to polystyrene, an important finding because these are known fish and human pathogens. These results highlight species-dependent biofilm triggers and their substantial variability and provide guidance for standardized marine biofilm protocols. Full article