Seawater Fish Research Articles

Morphological and transcriptional analysis of sexual differentiation and gonadal development in a burrowing fish, the four-eyed sleeper (Bostrychus sinensis)

Four-eyed sleeper (Bostrychus sinensis) is a commercially important sea water fish, and the male individuals exhibit significant advantages in somatic growth and stress resistance, so developing sex control strategy to create all-male progeny will produce higher economic value. However, little is known about the genetic background associated with sex differentiation in this species. In this study, we investigated gonadal development and uncovered critical window stages of sexual differentiation (about 2 mph), transition from proliferation to differentiation in female germ stem cells (GSCs) (2–3 mph) and male GSCs (3–4 mph). De novo transcriptome analysis revealed candidate genes and signaling pathways associated with sexual differentiation and gonadal development in four-eyed sleeper. The results showed that sox9 and zglp1 were the earliest sex-biased transcription factors during sex differentiation. Down-regulation of chemokine, cytokines-cytokine receptors and up-regulation of cellular senescence pathway might be involved in GSC differentiation. Weighted gene correlation network analysis showed that metabolic pathway and occludin were the hub signaling and gene in ovarian development, meanwhile the MAPK signaling pathways, cellular senescence pathway and ash1l (histone H3-lysine4 N-trimethyltransferase) were the hub pathways and gene in testicular development. The present work elucidated the developmental processes of sexual differentiation and gonadal development and revealed their associated revealed genes and signaling pathways in four-eyed sleeper, providing theoretical basis for developing sex-control techniques.

Mercury isotope compositions in seawater and marine fish revealed the sources and processes of mercury in the food web within differing marine compartments.

Anthropogenic activities and climate change have significantly increased mercury (Hg) levels in seawater. However, the processes and sources of Hg in differing marine compartments (e.g. estuary, marine continental shelf (MCS) or pelagic area) have not been well studied, which makes it difficult to understand Hg cycling in marine ecosystems. To address this issue, the total Hg (THg) concentration, methylmercury (MeHg) concentration and stable Hg isotopes were determined in seawater and fish samples collected from differing marine compartments of the South China Sea (SCS). The results showed that the estuarine seawater exhibited substantially higher THg and MeHg concentrations than those in the MCS and pelagic seawater. Significantly negative δ202Hg (-1.63‰ ± 0.42‰) in estuarine seawater compared with that in pelagic seawater (-0.58‰ ± 0.08‰) may suggest watershed input and domestic sewage discharge of Hg in the estuarine compartment. The Δ199Hg value in estuarine fish (0.39‰ ± 0.35‰) was obviously lower than that in MCS (1.10‰ ± 0.54‰) and pelagic fish (1.15‰ ± 0.46‰), which showed that relatively little MeHg photodegradation occurred in the estuarine compartment. The Hg isotope binary mixing model based on Δ200Hg revealed that approximately 74% MeHg in pelagic fish is derived from atmospheric Hg(II) deposition, and over 60% MeHg in MCS fish is derived from sediments. MeHg sources for estuarine fish may be highly complex (e.g. sediment or riverine/atmospheric input) and further investigations are warranted to clarify the contribution of each source. Our study showed that Hg stable isotopes in seawater and marine fish can be used to identify the processes and sources of Hg in different marine compartments. This finding is of great relevance to the development of marine Hg food web models and the management of Hg in fish.

The impact of parasitic sea lice on harvest quantities and sizes of farmed salmon

Sec lice infections are recognized as a primary challenge for both salmon farming and adjacent stocks of wild salmon and sea trout, triggering strict regulations at farm sites and in larger coastal production areas. In 2017 the Norwegian government implemented the Traffic Light System (TLS), where green, yellow, and red lights imply that salmon farmers can raise, maintain, or must reduce production quantities depending on estimated sea lice-induced mortality of wild salmonids. Past research has explored the impacts of sea lice on the growth rate of salmon, indicating a possible link between sea lice numbers and harvest practices. This study evaluates the impact of sea lice on salmon farmers' harvest behavior focusing on production quantities and fish sizes while controlling for market prices of salmon and fish meal. We also investigate whether and to what extent the TLS implementation affects harvest behavior. Our empirical results indicate that farmers tend to harvest marginally faster in response to increasing levels of sea lice and slower during delousing operations. The implementation of the TLS strengthened the negative impacts of delousing operations on harvest quantities. Fish sizes at harvest are negatively associated with sea lice levels and delousing operations, regardless of the implementation of the TLS. Control variables, such as seawater temperature, salmon prices, and fish meal prices, also influence harvest quantities and fish sizes.

The Allergenicity Potential of Edible Freshwater Fish

A Freshwater fish is a popular type of fish consumed in Indonesia besides seawater fish. However, until now the most available information regarding the potential allergenicity of fish is only related to seawater fish. The potential allergenicity of freshwater fish has not been studied much, so it has not been identified and characterized. Based on this, this review aims to collect information regarding the potential allergenicity of protein in freshwater fish and the effect of processing on this potential. The potential allergenicity of proteins in several freshwater fish has been confirmed by immunoblotting and ELISA, namely mujair, nile, catfish, mas, toman, janjan, tambakan, tiger scat, barramundi, and eel. The identified allergenic proteins include parvalbumin, tropomyosin, enolase, aldolase, creatine kinase, triosephosphate isomerase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphate isomerase, and glyceraldehyde-3-phosphate dehydrogenase. In addition, several proteins in other freshwater fish also have allergenicity potential but have not been confirmed through research, namely pomfret, gourami, snakehead, catfish, eel, betutu, and cetol. The potential allergenicity of fish protein is also influenced by the processing process. Changes in the potential allergenicity are related to the characteristics of each allergen protein. Therefore, it is necessary to select the appropriate processing so that potential allergenicity can be suppressed.

Role of the kidneys in acid-base regulation and ammonia excretion in freshwater and seawater fish: implications for nephrocalcinosis.

Maintaining normal pH levels in the body fluids is essential for homeostasis and represents one of the most tightly regulated physiological processes among vertebrates. Fish are generally ammoniotelic and inhabit diverse aquatic environments that present many respiratory, acidifying, alkalinizing, ionic and osmotic stressors to which they are able to adapt. They have evolved flexible strategies for the regulation of acid-base equivalents (H+, NH4 +, OH- and HCO3 -), ammonia and phosphate to cope with these stressors. The gills are the main regulatory organ, while the kidneys play an important, often overlooked accessory role in acid-base regulation. Here we outline the kidneys role in regulation of acid-base equivalents and two of the key 'urinary buffers', ammonia and phosphate, by integrating known aspects of renal physiology with recent advances in the molecular and cellular physiology of membrane transport systems in the teleost kidneys. The renal transporters (NHE3, NBC1, AE1, SLC26A6) and enzymes (V-type H+ATPase, CAc, CA IV, ammoniagenic enzymes) involved in H+ secretion, bicarbonate reabsorption, and the net excretion of acidic and basic equivalents, ammonia, and inorganic phosphate are addressed. The role of sodium-phosphate cotransporter (Slc34a2b) and rhesus (Rh) glycoproteins (ammonia channels) in conjunction with apical V-type H+ ATPase and NHE3 exchangers in these processes are also explored. Nephrocalcinosis is an inflammation-like disorder due to the precipitation of calcareous material in the kidneys, and is listed as one of the most prevalent pathologies in land-based production of salmonids in recirculating aquaculture systems. The causative links underlying the pathogenesis and etiology of nephrocalcinosis in teleosts is speculative at best, but acid-base perturbation is probably a central pathophysiological cause. Relevant risk factors associated with nephrocalcinosis are hypercapnia and hyperoxia in the culture water. These raise internal CO2 levels in the fish, triggering complex branchial and renal acid-base compensations which may promote formation of kidney stones. However, increased salt loads through the rearing water and the feed may increase the prevalence of nephrocalcinosis. An increased understanding of the kidneys role in acid-base and ion regulation and how this relates to renal diseases such as nephrocalcinosis will have applied relevance for the biologist and aquaculturist alike.

Analysis of fresh seawater fish production value for 2016 – 2020 in Bima District

Fisheries are among the leading resources in the Bima District area. This is because of aquaculture and capture fisheries. This condition is caused by the Bima district area being surrounded by the Indian Ocean, Flores Sea, and Sape Strait waters. Therefore, this study aimed to determine the production value of fresh seawater fish in the Bima district area and the SLS value. Observations were made by analyzing data on wet sea fish production value in each sub-district during 2016 – 2020. Data were obtained from the Bima Regency Maritime Affairs and Fisheries Service. From the observation results, it was found that the water fish production value was obtained in the Sape Sub District at 231957.21 tons and the lowest was in the Parado Sub-District which was 55694.1 tons. Meanwhile, if the sales value of fresh seawater fish, only Sape Sub-District has a sales value of IDR 1,033,373,551,615 and at the same time is the highest value compared to other sub-districts with sales values below IDR 200,000,000.

Feasibility Analysis of Koi Fish Cultivation with the Use of Rice Fields as Cultivation Sites

Indonesia's biodiversity is very diverse, especially ornamental fish, both seawater and fresh water ornamental fish. Commodities of freshwater ornamental fish cultivated in Indonesia are not only local ornamental fish but imported freshwater ornamental fish such as Koi (Cyrpinus carpio) have also been cultivated in several regions of Indonesia. Kediri is a very potential area, especially in the field of ornamental fish cultivation. The Koi fish cultivation center in Kediri is not inferior to the cultivation in the Blitar area which is already famous for Koi fish cultivation. The traditional pond pattern using rice fields as a place for Koi fish cultivation has proven that with makeshift facilities the people of Pranggang Village are able to help their economy. These advantages make this commodity have business prospects that can be developed through cultivation activities. so it is necessary to do a business feasibility analysis to develop a koi fish farming business in the future. Retrieval of data used in this study is the method of observation, interviews and documentation. while for the analysis using qualitative methods, where the researcher as the key instrument, data collection techniques were carried out by means of triangulation (combined). Qualitative method analysis carried out in this study includes business management, production inputs, production processes, outputs, marketing and business development plans.

Freshwater transfer affected intestinal microbiota with correlation to cytokine gene expression in Asian sea bass.

As a catadromous fish, Asian sea bass (Lates calcarifer) juveniles migrate from seawater (SW) to freshwater (FW) for growth and development. During migration, they undergo physiological changes to acclimate to environmental salinity. Thus, it is crucial to understand how SW-to-FW migration affects the gut microbiota of catadromous fish. To the best of our knowledge, no study has revealed the effects of transfer to hypotonic environments on a catadromous fish microbiota. In this study, we aimed to determine the effects of FW transfer on the microbiota and cytokine gene expression in the intestines of juvenile catadromous Asian sea bass. The relationship between the water and the gut microbiota of this euryhaline species was also examined. We found that FW transfer affected both mucosa- and digesta-associated microbiota of Asian sea bass. Plesiomonas and Cetobacterium were dominant in both the mucosa- and digesta-associated microbiota of FW-acclimated sea bass. The pathogenic genera Vibrio, Staphylococcus, and Acinetobacter were dominant in the SW group. Although dominant fish microbes were present in the water, fish had their own unique microbes. Vitamin B6 metabolism was highly expressed in the FW fish microbiota, whereas arginine, proline, and lipid metabolism were highly expressed in the SW fish microbiota. Additionally, the correlation between cytokine gene expression and microbiota was found to be affected by FW transfer. Taken together, our results demonstrated that FW transfer altered the composition and functions of mucosa- and digesta-associated microbiota of catadromous Asian sea bass intestines, which correlated with cytokine gene expression.

Euryhaline fish larvae ingest more microplastic particles in seawater than in freshwater

Microplastic (MP) pollution is a major concern in aquatic environments. Many studies have detected MPs in fishes; however, little is known about differences of microplastic uptake by fish in freshwater (FW) and those in seawater (SW), although physiological conditions of fish differ significantly in the two media. In this study, we exposed larvae (21 days post-hatching) of Oryzias javanicus (euryhaline SW) and Oryzias latipes (euryhaline FW), to 1-µm polystyrene microspheres in SW and FW for 1, 3, or 7 days, after which, microscopic observation was conducted. MPs were detected in the gastrointestinal tracts in both FW and SW groups, and MP numbers were higher in the SW group in both species. Vertical distribution of MPs in the water, and body sizes of both species exhibited no significant difference between SW and FW. Detection of water containing a fluorescent dye revealed that O. javanicus larvae swallowed more water in SW than in FW, as has also been reported for O. latipes. Therefore, MPs are thought to be ingested with water for osmoregulation. These results imply that SW fish ingest more MPs than FW fish when exposed to the same concentration of MPs.

Using renowned chefs for VeriTaste™ as a sensory method analysis in food products – A comparison of Atlantic salmon stored in refrigerated seawater and on ice

Sensory evaluation is an important quality analysis for examining the characteristics of a food product. This study presents a new sensory analysis method using renowned chefs, branded Veritaste™, to evaluate raw and cooked fillets of Atlantic salmon originating from refrigerated seawater (RSW) versus traditional ice whole fish storage. Quality parameters were also studied, including the fillet index method and cook loss. The raw fillets from the RSW-stored fish had a more distinct salty taste compared to the traditionally stored fish. In addition, the RSW-stored salmon gave a lower cook loss. Otherwise, there were minimal differences in the sensory parameters observed and the fillet index measurements. Both Veritaste™ and the fillet index measurements showed that judges significantly influence the sensory quality parameters. It is concluded that Veritaste™ can serve as supplementary information in addition to the common sensory analyses done today. This method has the potential to be further improved, optimised, and extended to other food products.

Seawater fish use an electrogenic boric acid transporter, Slc4a11A, for boric acid excretion by the kidney

Boric acid is a vital micronutrient in animals; however, excess amounts are toxic to them. Little is known about whole-body boric acid homeostasis in animals. Seawater (SW) contains 0.4mM boric acid, and since marine fish drink SW, their urinary system was used here as a model of the boric acid excretion system. We determined that the bladder urine of a euryhaline pufferfish (river pufferfish, Takifugu obscurus) acclimated to fresh water and SW contained 0.020 and 19mM of boric acid, respectively (a 950-fold difference), indicating the presence of a powerful excretory renal system for boric acid. Slc4a11 is a potential animal homolog of the plant boron transporter BOR1; however, mammalian Slc4a11 mediates H+ (OH-) conductance but does not transport boric acid. We found that renal expression of the pufferfish paralog of Slc4a11, Slc4a11A, was markedly induced after transfer from fresh water to SW, and Slc4a11A was localized to the apical membrane of kidney tubules. When pufferfish Slc4a11A was expressed in Xenopus oocytes, exposure to media containing boric acid and a voltage clamp elicited whole-cell outward currents, a marked increase in pHi, and increased boron content. In addition, the activity of Slc4a11A was independent of extracellular Na+. These results indicate that pufferfish Slc4a11A is an electrogenic boric acid transporter that functions as a B(OH)4- uniporter, B(OH)3-OH- cotransporter, or B(OH)3/H+ exchanger. These observations suggest that Slc4a11A is involved in the kidney tubular secretion of boric acid in SW fish, probably induced by the negative membrane potential and low pH of urine.

Occurrence, partition, and risk of four adjacent transition metals in seawater, sediments and demersal fish from the Pearl River Estuary, South China Sea.

The spatio-seasonal variation, bioaccumulation and potential ecological risk of four metals (Co, Ni, Cu and Zn) in the multi-media of the Pearl River Estuary (PRE) were assessed. The degree of contamination and ecological risk of the four metals followed this pattern: Cu>Zn>Ni>Co, upstream > downstream, wet season > dry season. There were non-linear and linear correlations for Co, linear and non-linear correlations for Ni, and non-linear and no correlation for both Cu and Zn, between metals in bottom water or bioavailable concentrations in sediment and fish muscle. Co and Ni showed lightly polluted levels; Cu and Zn showed heavily polluted levels. This study demonstrates a tendency of cross-accumulation in fish of these four transition metals within specific habitats of the PRE.

Trimethylamine N-oxide-derived zwitterionic polyamide thin-film composite nanofiltration membranes with enhanced anti-dye deposition ability for efficient dye separation and recovery

Organic dyes from textile industries are becoming the second largest pollutants in the world. In this study, inspired by the seawater fish, a new diamine monomer, N,N-bis(3-aminopropyl)methylamine N-oxide (DNMAO) with a trimethylamine N-oxide (TMAO)-derived “N+─O−” zwitterionic functionality, has been designed for the fabrication of polyamide thin-film composite (TFC) membranes to purify dye-contaminated water and recover organic dyes. The fabricated membranes show enhanced permeability and improved anti-dye-deposition performance. The optimum membrane fabricated at 0.5 wt% of DNMAO feed solution exhibits an ultrahigh pure water permeability (PWP) of 37.5 LMH bar−1, a superior Congo red (CR) rejection of 99.93%, and a low sodium chloride (NaCl) rejection of 9.3%, indicating its outstanding performance for dye/salt separation. It can also achieve the complete CR removal from a feed with a low CR concentration of 1 ppm, demonstrating its superior separation performance for the production of clean potable water. In addition, the low dye loss rate (6.22%) and high salt removal rate (85.6%) are achieved during the purification and recovery test with CR/NaCl mixtures. Furthermore, the optimum membrane possesses an excellent anti-dye-deposition performance with a flux recovery ratio (FRR) of 92.1%. All these results demonstrate its potential for applications in not only textile wastewater treatment but also organic dye purification and recovery.

Design and Implementation of a Smart Seawater Aquarium System Based on Artificial Intelligence of Things Technology

In recent years, single societies and aging societies around the worldwide increasingly seen the emerging problem of loneliness and the growing need for companionship. To satisfy the need, the population of pet keepers is growing, and the proportion of households with pets is increasing. It is normal to have pets at home. Pet fish are kept not only for companionship but also to relieve the stress accumulated throughout the day, and they can also improve the quality of life and health of older individuals. Having a pet can help reduce anxiety and increase food intake in people with medical conditions. This article proposes a smart seawater aquarium system based on the artificial intelligence of things (AIoT) technology to lower the knowledge threshold for keeping seahorses or other marine fish as pets. The proposed system provides seawater fish owners with safe and convenient feeding methods and more pet-friendly and user-friendly choices of interactive pet care and improves the comfort and survival rate of marine life in seawater aquariums. This smart seawater aquarium system can automatically or manually adjust water quality, water temperature, and oxygen content in water, change the water, feed fish, and monitor underwater fish in real time. It solves the problem of neglecting pet fish and the difficulty of maintaining seawater aquariums. Moreover, the proposed system incorporates a cloud-based information system and a web-based platform for data transmission and interface control, and it has achieved the purposes of remote and local monitoring of the aquarium.

Metabolic costs associated with seawater acclimation in a euryhaline teleost, the fourspine stickleback (Apeltes quadracus).

The cost of osmoregulation in teleosts has been debated for decades, with estimates ranging from one to 30 % of routine metabolic rate. The variation in the energy budget appears to be greater for euryhaline fish due to their ability to withstand dynamic salinity levels. In this study, a time course of metabolic and physiological responses of the euryhaline fourspine stickleback (Apeltes quadracus) acclimated to freshwater (FW) and then exposed to seawater (SW) was examined. There was 18% mortality in the first 3 days following exposure to SW, with no mortalities in the FW control group. Gill Na+/K+-ATPase (NKA) activity, an index of osmoregulatory capacity, increased 2.6-fold in SW fish peaking on days 7 and 14. Gill citrate synthase activity, an index of aerobic capacity, was 50-62% greater in SW than FW fish and peaked on day 7. Tissue water content was significantly lower in the SW fish on day 1 only, returning to FW levels by day 3. Routine metabolic rate was decreased within 24h of SW exposure and was maintained slightly (8-22%) but significantly lower in SW compared to FW water controls throughout the 2-week experiment. These results indicate that elevated salinity resulted in increased SW osmoregulatory and aerobic capacity in the gill, but with a reduced whole animal metabolic rate to this euryhaline species.

Uji Toksisitas Ekstrak Daun Sirih (Piper betle) Terhadap Benih Ikan Kakap Putih (Lates calcarifer)

White snapper (Lates calcarifer) is a type of seawater fish that is in great demand by the public. This study aims to determine the 48-hour LC50 value and the effect of using betel leaf extract on the health status of white snapper. This research was conducted in July 2020 which took place at the Sekotong Coastal Aquaculture Development Center (BPBPP), West Lombok Regency, West Nusa Tenggara. This research was conducted using experimental methods. This study used 5 treatments and three replications, to obtain 15 experimental units with doses of 0 ppm, 80 ppm, 90 ppm, 100 ppm and 200 ppm. Data analysis was performed using a linear regression test, namely probit analysis by testing the mortality of tested animals and calculated through statistical data using Microsoft Excel. The higher the betel leaf extract concentration, the higher the number of white snapper seed deaths. This happens because the betel leaf extract contains active antimicrobial compounds, but at high concentrations, it can poison the white snapper seeds. For further research, it is recommended to test the toxicity of betel leaf extract on the mortality of white snapper with variations in water quality.

Nutritional Characteristics of Lempuk (Gobiopterus sp.) Endemic Fish, at Ranu Grati Lake, Pasuruan, Indonesia

Exploration of natural resources from the Lake of Ranu Grati was carried out on Lempuk fish (Gobiepterus sp). This study aimed to investigate the nutritional value of Lempuk fish (Gobiepterus sp.) consisting of proximate content, amino acids, and fatty acids. The fish sample was collected in July 2021. Standard proxymate analysis was used for protein, fat, moisture, and ash. The results showed that Lempuk fish had relatively similar proximate content to other freshwater fish and seawater fish. The proximate content of the fish is protein (14 %), lipid (7.08 %), moisture (79.27%), and dry base ash (10.67%). Glutamic acid in Lempuk fish is high. It is a medium-fat fish. Fatty acid results showed that Lempuk fish contains a large amount of unsaturated fatty acids. Hence, it is suitable for food and also reduces human cardiovascular diseases. This study concludes that the Lempuk fish (Gobiepterus sp.) has good nutritional value and is ideal for human consumption.

Infection of Infectious Spleen and Kidney Necrosis Virus and Viral Nervouse Necrosis in Seawater Fish Identifed Using Multiplex Polymerase Chain Reaction

Indonesia become a maritime country with large of ocean area and beach line with marine species diversity reaches 37% of the world’s fish. This makes Indonesia have aquaculture potential that supported by an appropriate climate. However, the challenge of viral diseases caused by Infectious Spleen and Kidney Necrosis Virus (ISKNV) and Viral Nervous Necrosis (VNN) would hamper marine aquaculture and causing huge economic losses. Therefore, it is necessary to carry out early detection methods that are efficient, fast, precise and accurate to identifying these viral disease. Here we developed a multiplex-PCR (mPCR) a method that can detect simultaneously of the ISKNV and VNN. The results of this method showed high sensitivity and specificity by using MCP and CP gene target primers to detect ISKNV and VNN, respectively. From a total of 353 samples of seawater fish examined by mPCR, positive results following of single infection of ISKNV and VNN were 14 and 2, respectively. We also found that 18 grouper fish was co-infection with these viruses. From these results, it shows that the mPCR method developed has efficiency, faster and high accuracy. This founding was possible to be applied in laboratory testing or early detection system in the field for ISKNV and VNN.

Membrane Transport Proteins Expressed in the Renal Tubular Epithelial Cells of Seawater and Freshwater Teleost Fishes.

The kidney is an important organ that maintains body fluid homeostasis in seawater and freshwater teleost fishes. Seawater teleosts excrete sulfate and magnesium in small amounts of isotonic urine, and freshwater teleosts excrete water in large amounts of hypo-osmotic urine. The volume, osmolality, and ionic compositions of the urine are regulated mainly by membrane transport proteins expressed in the renal tubular epithelial cells. Gene expression, immunohistochemical, and functional analyses of the fish kidney identified membrane transport proteins involved in the secretion of sulfate and magnesium ions by the proximal tubules and reduction of urine volume by the collecting ducts in seawater teleosts, and excretion of water as hypotonic urine by the distal tubules and collecting ducts in freshwater teleosts. These studies promote an understanding of how the kidney contributes to the seawater and freshwater acclimation of teleosts at the molecular level.

The effects of hydrogen incorporation in modified atmosphere packaging on the formation of biogenic amines in cold stored rainbow trout and horse mackerel

The formation of biogenic amines (BAs) in fish products during storage forms a serious challenge to producers and is generally related to the growth of decarboxylase-producing microorganisms. Controlling the formation of BAs is a serious challenge for the fishery industry. This study evaluates the impact of incorporating molecular hydrogen (H2) in a modified atmosphere packaging on the formation of BAs in both freshwater and seawater fish, i.e., rainbow trout and horse mackerel, respectively, stored at + 4 °C for 15 days. Fish samples were packaged in modified atmosphere packaging [MAP1 (50% CO2/50% N2) and MAP2 (60% CO2/40% N2)], reducing atmosphere packaging [RAP1 (50% CO2/46% N2/4% H2) and RAP2 (60% CO2/36% N2/4% H2)], and under air (control). The amount of BAs, except spermidine and spermine, significantly increased during storage in all treated samples. Both MAPs and RAPs showed significant restrictive effects on the formation of heterocyclic, aromatic, and aliphatic di-amines (histamine, tyramine, putrescine, cadaverine) in both fish species, with a more potent effect seen in RAP rather than MAP. Reduction rates of BAs ‎were about two folds higher in RAPs than that of MAPs. This shows the advantage of hydrogen incorporation in the package atmosphere on the inhibition of biogenic amine formation, especially in the presence of a high level of CO2. Therefore, RAP may be proposed as a promising technology for limiting the BA formation in fishery products.