Aquaculture Waste Research Articles

Rearing fly larvae on various substrates: nutrient composition of larvae and frass.

Management solutions for waste in southern Thailand, such as fly larvae, are tested in a laboratory using different substrates and wastes from the Thai agricultural sector. The nutritional content of the immature stages of Musca domestica Linnaeus (Diptera: Muscidae) and Hermetia illucens (Linnaeus) (Diptera: Stratiomyidae) larvae, especially their protein and fat contents, makes them a potential animal feed. Laboratory strains of M. domestica and H. illucens were reared on selected substrates to examine how diet influenced their performance and nutritional composition. Waste from aquaculture, vegetables, and fruits in southern Thailand was examined for larval diet and showed promise as a rearing substrate for these insects. Musca domestica larvae reared on fishery waste achieved the highest larval weight and fat content, whereas H. illucens larvae reared on an aquaculture waste diet had the highest protein content. These findings imply aquaculture waste could be the best choice for large-scale fly larvae production, particularly as a protein feed additive.

A Gastronomic Approach to Industrial Aquaculture Waste Utilization

Aquaculture, while offering significant contributions to global food security, generates substantial amounts of industrial waste, posing environmental and economic challenges. However, this waste also presents untapped potential for innovation in gastronomy. This paper explores the emerging trend of utilizing aquaculture industrial wastes in culinary practices, aiming to reduce waste, promote sustainability, and create novel gastronomic experiences. Through a review of literature and case studies, we examine various methods for repurposing aquaculture waste, including upcycling into new food products, incorporation into culinary dishes, and extraction of valuable components. Additionally, we highlight successful initiatives that have integrated aquaculture waste into gastronomy, emphasizing the benefits of waste reduction, sustainable food practices, and culinary innovation. Challenges such as food safety, taste, and consumer acceptance are acknowledged, with strategies proposed for addressing these issues. Finally, we discuss future directions for research and development in this field, identifying opportunities for collaboration between the aquaculture industry and the gastronomy sector. By exploring the utilization of aquaculture industrial wastes in gastronomy, this paper contributes to a deeper understanding of sustainable food practices and culinary creativity in the context of aquaculture waste management.

Influence of an innovative IMTA system (Mediterranean Sea, Italy) on environmental and biological parameters: Seasonal analysis

The influence of benthic suspension feeders as bioremediating organisms on water column seston and their ability to mitigate fish farm waste was assessed by monthly analyses for one year. A monthly monitoring from July 2020 to October 2021 of physico-chemical and biochemical variables of the water column and the sediment was performed in an in-shore mariculture plant located in the Mar Grande of Taranto (Italy), comparing two adjacent areas that differ in type of farming. The first (reference site) is a fish monoculture, while the second consists of an innovative Integrated Multi-Trophic Aquaculture system (IMTA site). The annual cycle of chlorophyll-a concentration showed values corresponding to mesotrophic/eutrophic conditions, with peak production in early fall (4.64 μg L−1). During the spring and summer sampling times, when the amount of aquaculture waste is greater than during the rest of the year, the reference site showed the highest lipid (151.73 μg L−1) and organic matter (189.00 mg g−1) values with respect to those at the IMTA site. The IMTA bioremediating organisms possibly acted as underwater gardens changing the seston quality and availability and providing protection and food for the zooplankton community, which showed higher abundance of individuals for most sampling times at the IMTA site, peaking during September and October in both 2020 and 2021 (max 232,985.20 ind m−3). Our results demonstrate the effectiveness of the considered IMTA system in mitigating the negative impact of organic matter release into the environment due to fish farming activities. The influence of bioremediating organisms on seston composition and concentration opened up mitigation as well as restoration scenarios.

Enzymes from Fishery and Aquaculture Waste: Research Trends in the Era of Artificial Intelligence and Circular Bio-Economy.

In the era of the blue bio-economy, which promotes the sustainable utilization and exploitation of marine resources for economic growth and development, the fisheries and aquaculture industries still face huge sustainability issues. One of the major challenges of these industries is associated with the generation and management of wastes, which pose a serious threat to human health and the environment if not properly treated. In the best-case scenario, fishery and aquaculture waste is processed into low-value commodities such as fishmeal and fish oil. However, this renewable organic biomass contains a number of highly valuable bioproducts, including enzymes, bioactive peptides, as well as functional proteins and polysaccharides. Marine-derived enzymes are known to have unique physical, chemical and catalytic characteristics and are reported to be superior to those from plant and animal origins. Moreover, it has been established that enzymes from marine species possess cold-adapted properties, which makes them interesting from technological, economic and sustainability points of view. Therefore, this review centers around enzymes from fishery and aquaculture waste, with a special focus on proteases, lipases, carbohydrases, chitinases and transglutaminases. Additionally, the use of fishery and aquaculture waste as a substrate for the production of industrially relevant microbial enzymes is discussed. The application of emerging technologies (i.e., artificial intelligence and machine learning) in microbial enzyme production is also presented.

The aquaculture waste as the carbon source for nanocellulose production by Komagataeibacter europaeus

The aquaculture waste as the carbon source for nanocellulose production by <i>Komagataeibacter europaeus</i>

Stakeholders' assessment of feed produced from nutrients recovered from aquaculture waste in an emerging economy

The intensified aquaculture production and heavy feed use have placed high pressure on the environment due to increasing waste. This study aims to understand how stakeholders along the aquaculture value chain evaluate feed produced from nutrients recovered from waste in aquaculture production. Using a mixed method combining a systematic literature analysis by synthesizing 171 articles and a qualitative analysis with information collected from 45 respondents including fishmeal producers, feed producers, feed traders, hatcheries, farmers, shrimp traders, and shrimp processors cum exporters in an emerging economy of Viet Nam, the study reveals that the stakeholders in the value chain are aware of and willing to accept the feed produced from nutrients recovered from waste in aquaculture production. The motivation of each stakeholder to produce or use the feed is conditional on that of other stakeholders. The findings suggest that the removal of conditional motivation cannot be left to the market and government support is needed.

Composite of activated carbon-hydroxyapatite from corn (Zea mays L.) cob and catfish (Pangasius sp.) bones with H3PO4 activation for methylene blue dye adsorption

Methylene blue (MB) is a synthetic dye in wastewater that causes serious environmental problems due to its toxicity, carcinogenicity, and resistance to environmental degradation. To overcome this problem, activated carbon (AC) from corncob waste and natural Hydroxyapatite (HAp) from catfish bone were synthesized to generate a simple, cost-effective, and efficient composite adsorbent for removing MB dye in wastewater. The performance of the AC/HAp composite adsorbent was assessed under varying conditions, including initial dye concentration, contact time, adsorbent dosage, pH, and reusability. The scanning electron microscope (SEM) morphology and BET results showed that the composite had an irregular shape, with a specific surface area of 419.02 m2/g. The results showed that the isotherm model followed the Langmuir model with an adsorption capacity of 109.90 mg/g. Reusing the composite adsorbent after 3 cycles resulted in an insignificant decrease in the MB removal percentage from 73.52 % to 55.32 % at an initial dye concentration of 200 mg/L. Ion exchange, hydrogen bonding, Lewis acid-base interaction, electrostatic interaction, and π–π bond interactions were several adsorption mechanisms. Based on these findings, the composite had the potential to be an MB adsorbent by enhancing agricultural and aquaculture waste value and supporting the implementation of a circular economy and net zero carbon in Indonesia.

Waste to wealth- a transformative perspective in greening the environment with a focus on fisheries and aquaculture: emerging cutting edge trends

This article explores the growing potential of the waste-to-wealth approach in the fisheries and aquaculture sectors. It argues that by viewing waste as a resource, these sectors can achieve significant environmental and economic benefits. The editorial highlights the concerning volume of waste generated in fisheries and aquaculture, including unwanted fish, aquaculture waste, and plastic pollution. It then discusses the potential of waste-to-wealth solutions, such as fish waste valorization, aquaculture wastewater treatment, and plastic pollution reduction. The editorial emphasizes the crucial role of environmental biology in driving this revolution by providing expertise in ecosystem understanding, waste management optimization, sustainable resource management, and monitoring and evaluation. Finally, it highlights the future direction of environmental biology in this context, focusing on innovative technology development, long-term ecological understanding, and stakeholder collaboration.. KEYWORDS :Circular economy,Fish waste valorization,Plastic pollution reduction,Sustainable resource management,Waste management,Waste-to-wealth

Performance of feeding black soldier fly (Hermetia illucens) larvae on shrimp carcasses: A green technology for aquaculture waste management and circular economy

Over 944 thousand tonnes of shrimp carcasses are produced worldwide during the shrimp production cycle, and black soldier fly larvae (BSFL) are a potential solution for this shrimp carcass accumulation. In this study, we evaluated the performance of BSFL feeding on shrimp carcasses. Six combinations of wheat bran and shrimp carcass powder (with replacement increments of 20 %) and one whole shrimp carcasses treatment were tested. The bioconversion rate (27.15 ± 3.66 %; p = 0.001), crude protein (55.34 ± 1.27 %; p < 0.001), and crude lipid (14.37 ± 1.86 %; p = 0.007) values of BSFL reared on whole shrimp carcasses were significantly higher than those of BSFL reared on wheat bran. Increasing the shrimp carcass amount in the feeding media resulted in significant increases in BSFL docosahexaenoic acid (with the highest value occurring for BSFL reared on whole shrimp carcasses; 1.46 ± 0.09 %; p < 0.001). Conversely, BSFL docosahexaenoic acid was not detected for BSFL reared on wheat bran. The detected heavy metal concentrations in BSFL were below the limits of the published international guidelines for animal feed. In the obtained BSFL, Salmonella was not detected, and the mould count was <10 CFU/g. The total bacterial count (Lg transformation) of obtained BSFL ranged from 7.88 to 8.07 CFU/g, and no significant differences among all treatments (p = 0.424). Overall, this study demonstrates that BSFL-based bioconversion presents a resource recovery technology for converting shrimp carcasses into high-value nutritional biomass.

Enhanced biodegradation of sulfamethoxazole by pyrogenic carbon derived from aquacultural waste sludge

Sulfamethoxazole (SMX) is a widely utilized antibiotic that exhibits a broad spectrum of antibacterial activity, but its inadvertent release into the environment poses a significant threat to human society. The inefficacy of SMX degradation in microbial pipelines constantly challenges the regulation of antibiotics, making it a pressing and compelling concern. Former research has demonstrated the enhancement of the waste sludge-derived materials on SMX biodegradation, but the impact of these materials on microbial behavior remains unclear. In this study, two pyrogenic carbon materials (FBC and RBC) were prepared from aquacultural waste sludge and its downstream river sediment, respectively, to collaborate with SMX degrading species, Alcaligenes sp., for highly efficient removal of SMX. The cells of Alcaligenes sp. successfully colonized onto the biocompatible surface of the materials, and this hybrid structure nearly doubled the SMX degradation efficiency of the group without the carbon materials. The transcriptome analysis revealed that the existence of carbon materials significantly upregulated the expression of SMX degrading-related genes, including metCF and paaCIK, which led to bond breaking and benzene ring breakdown for the degradation of sulfamethoxazole. This work provides new insights into the mechanisms and environmental significance of SMX degradation by microbial immobilization onto waste-derived carbon-rich materials.

Retracted: Conversion of Aquaculture Waste into Biomedical Wealth: Chitin and Chitosan Journey

Retracted: Conversion of Aquaculture Waste into Biomedical Wealth: Chitin and Chitosan Journey

Water quality management in aquaculture

Abstract The aquaculture industry requires good water quality for its successful operation but produces wastes that can cause environmental deterioration and pose high risks to the sector. Adequate waste treatment and recycling are necessary to make aquaculture a sustainable and profitable industry and contribute to the circular economy. Polluted water sources, excess feeding, overstocking, use of antibiotics/chemicals and harmful algal blooms are major causes of water quality deterioration and low production in aquaculture systems. Discharges of untreated wastes would have serious impacts on the receiving water bodies, and eventually on the aquaculture industry itself. Possible solutions include technological innovations in environmentally friendly production systems, use of efficient processes in water quality management and improved legislation and governance. Environmentally feasible aquaculture production technologies such as recycling aquaculture system, integrated multi-trophic aquaculture and aquaponics including features of waste recycling are viable options in aquaculture schemes. Best aquaculture practices integrating advanced water quality treatment processes and technologies, supported by automation and sensors, modeling and artificial intelligence-internet of things are necessary for a sustainable aquaculture environment, production and stable value chain. In general, low-cost technologies for aquaculture waste treatment and environmental impact reduction through good governance are crucial for achieving sustainability in the aquaculture industry and natural environmental management.

Antimicrobial, Antioxidant and Anticoagulant Properties of Chitosan Extracted From Mole Crab, Emerita emeritus (Linnaeus, 1767)

The present study evidences the immunological properties of chitosan extracted from the shells of Emerita emeritus which includes antimicrobial, antioxidant, and anticoagulant activity. The extraction proceeded by subjecting the shells to demineralization, deproteinization, and deacetylation reactions. The presence of chitosan was analyzed using Fourier transform infrared (FTIR) spectroscopy. Antibacterial activity of chitosan displayed maximum inhibition for Bacillus subtilis and Pseudomonas aeruginosa when compared to Escherichia coli and Staphylococcus aureus. Similarly, the extracted chitosan highly inhibited Candida albicans than Aspergillus fumigatus. The minimum inhibitory concentration (MIC) of chitosan for different bacterial and fungal strains was also documented. The free radical scavenging activity of chitosan using 1,1-diphenyl2-picrylhydrazyl (DPPH), increased by 60.40%. The anticoagulant activity of chitosan was discovered when mixed with chicken blood. Overall, the study emphasizes the conversion of aquaculture waste products like crustacean exoskeleton into a beneficial chitosan and signifies the effectiveness of chitosan against invading microbes in aquaculture.

Integrated treatment device for aquaculture waste gas based on coupled aerodynamics

Integrated treatment device for aquaculture waste gas based on coupled aerodynamics

Photosynthetic Bacteria as an Alternative Wastewater Treatment in Freshwater Aquarium Fish Set Up

Waste produced from aquaculture ultimately hampered the water quality and growth performance of species cultured. Therefore, the potential exploitation of photosynthetic bacteria (PSB) from aquaculture waste was investigated to treat the wastewater in the fish culture. In this study, the wastewater was collected from a fishpond and cultured in sunlight-exposed sterile bottles for 14 days. In the water additive experiment, five treatments (in a 30 cm3 aquarium) were prepared namely cultured PSB (T1), aquatic plant hornwort (T2), aquatic plant salvinia (T3), positive control (P), and negative control (N). Five individuals of Hyphessobrycon herbertaxelrodi (2.5±0.5 cm length) were placed in each treatment and reared for 30 days. Meanwhile, for the wastewater treatment, four treatments (in a 30 cm3 aquarium) were prepared namely wastewater from the hatchery fishpond (S1), wastewater from the hatchery fish tank (S2), positive control (P), and negative control (N). The results obtained indicate that T1 treatment significantly improved and maintained the water quality as compared to other treatments. The results showed the amount of ammonia and nitrite in S1 and S2 supplied with T1 for 30 days gradually decreased from day 1 until day 18. While zero amount of ammonia and nitrate was acquired from day 21 until day 30 of the wastewater experiment. The treatment with PSB showcased the bacteria's ability to utilize and absorb nutrients, thereby maintaining and improving water quality. The potential use of beneficial bacteria in the culture system can accelerate the nitrogen cycle for a sustainable way of wastewater management.

Effect of external acetate added in aquaculture wastewater on mixotrophic cultivation of microalgae, nutrient removal, and membrane contamination in a membrane photobioreactor

The mixotrophic cultivation of microalgae in wastewater has attracted extensive attention due to its many advantages. In this study, acetate, which can be prepared by hydrolysis of aquaculture waste, was used as exogenous organic matter to promote the growth of Chlorella pyrenoidosa cultured in aquaculture wastewater. Microalgae cultivation was carried out in a membrane photobioreactor (MPBR) with continuous inflow and outflow mode. The results showed that exogenous acetate greatly promoted the mixotrophic growth of C. pyrenoidosa. When the dosage of acetate reached 1.0 g L−1, the relative growth rate of microalgae in the logarithmic stage reached 0.31 d−1, which was 4.4 times that of the control. As a result, exogenous acetate also promoted the removal of nutrients from aquaculture wastewater. During the stable operation stage of the MPBR with acetate added in the influent, an average of 87.41%–93.93% nitrogen and 76.34%–88.55% phosphorus was removed from the aquaculture wastewater containing 19.41 mg L−1 total inorganic nitrogen and 1.31 mg L−1 total inorganic phosphorus. However, it was worth noting that adding exogenous acetate also led to an increase in the membrane resistance of the membrane module in the MPBR. Membrane resistance was mainly composed of internal resistance (Ri) and cake resistance (Rc), and with the increase of acetate content in the influent, their proportion in the total resistance gradually increased. Ri contributed the major membrane resistance and was most affected by acetate dosage. Ri reached 32.04 × 1012 m−1 with 1 g L−1 acetate, which accounted for 69.49% of total resistance. Moreover, with the increase of influent acetate concentration of the MPBRs, both the number of insoluble contaminants and dissolved organic contaminants in the membrane modules increased. In addition, the composition of proteins, polysaccharides, and humus in dissolved organic contaminants was close to that in extracellular polymeric substances and soluble microbial products secreted by microalgae. These results suggested that the membrane fouling of membrane modules was closely related to the algal biomass content in the MPBRs. The above results provided a theoretical basis for reducing membrane fouling of MPBR.

Sustainable Production of Tomato Using Fish Effluents Improved Plant Growth, Yield Components, and Yield in Northern Senegal

Aquaculture and agriculture integration is essential for maximizing water and land productivity in arid and semi-arid regions. Thus, the increase in global water scarcity and the dual use of water for crop and fish production has the potential to optimize water use, dispose of aquaculture wastes, provide additional nutrients to crops, and reduce inorganic fertilizer usage, thus maximizing farm productivity. This greenhouse study was conducted to determine the effects of fish effluents on the growth, yield parameters, and yield of tomatoes (Solanum lycopersicum L.). The experiment was carried out in a randomized complete block design with six replications. The 13 treatments consisted of three irrigation water types (river water—control, Nile tilapia—Oreochromis niloticus, African sharptooth catfish—Clarias gariepinus), four fertilizers (chicken manure, cow manure, sheep manure; recommended rate of NPK—280 kg ha−1 of 10-10-20), and six mixed treatments with fish effluent and 50% of the applied rate of manure alone. Results showed that irrigation with C. gariepinus effluent increased the stem diameter by 21%, the number of flowers by 88%, the fruit number by 50%, the fruit diameter by 24%, the mean fruit weight by 34%, and total fruit weight of tomato by 96% compared to NPK treatments. These effects were more evident when C. gariepinus was mixed with poultry, cow, and sheep manures, which resulted in significantly greater values than recommended rates of NPK. The higher productivity observed from the combined use of C. gariepinus and manure treatments (133% increase, on average) compared to NPK treatments was related to the continuous supply of nutrients and the increase of yield parameters. Therefore, the combined use of C. gariepinus effluent and manure can be a viable alternative for smallholder farmers, for whom inorganic fertilizers are often neither affordable nor available.

Environmental legacy of aquaculture and industrial activities in mangrove ecosystems

Aquaculture and industrial activities have been recognized for their detrimental impact on coastal environment, particularly through large-scale mangrove conversion. This study employs interdisciplinary spatial, geochemical, and metagenomic approaches to examine the environmental legacy of past aquaculture and industrial activities in mangrove rehabilitation areas. The land use change of mangrove, aquaculture, and industrial area was investigated from 1990 to 2020. Mangrove coverage increased in the study area from 49.12 ha in year 1990 to 95.93 ha in 2020. This growth can be attributed to increasing environmental awareness related to issues such as tidal flooding, seawater intrusion, and coastal abrasion. However, despite increasing mangrove coverage, we still identified fecal bacteria communities in both sites, dominated by Campylobacteria, Gammaproteobacteria, and Deltaproteobacteria. Additionally, our functional prediction analysis revealed the presence of genes associated with pathogenicity, multidrug/antibiotic resistance, and xenobiotic degradation. We observed high nitrate concentration associated with aquaculture waste that was persistent in porewater even after the activity ended years ago. Low to moderate heavy metal concentration was found in the study sites, likely due to the role of mangroves as a biofilter. We conclude that mangrove restoration contributes to the lower environmental impact of anthropogenic activities on our sites. Therefore, it should be included in future coastal management plans to improve coastal water quality and ecosystem function in environmentally threatened areas.

Acetylcellulose Recovery from Waste Residual for Attenuating Reactive Dye from Aquaculture Waste as a Fascinating Synergistic Ecology Effect

Waste valorization is attracting not only the scientific world but also the world. Acetylcellulose wastes from cigarette filter residuals are signified as the largest global impact of solid waste. Acetylcellulose recycling for desired products is a promising way for environmental management. In this regard, the current investigation is dealing with the immersion of residual filters sequentially into aqueous solutions of alkali and ethanol before water washing, which converts them into a superhydrophobic acetylcellulose adsorbent material. The morphology and characteristics of the acetylcellulose fiber were characterized using a Scanning Electron Microscope (SEM) and Fourier-Transform infrared spectroscopy (FTIR). The adsorption tendency was checked for Levafix Blue dye compromised in an aqueous stream as a model textile polluted effluent. The experimental results exposed that the acetylcellulose fiber displayed a sensible textile dye elimination from the dying stream. Langmuir isotherm is well fitting the adsorption matrix and the reaction follows the 1st-order kinetic model. The so-obtained acetylcellulose fiber showed tremendous efficiency for dye removal from aqueous effluent. The attained maximum monolayer adsorption capacity was recorded as 4.8 mg/g at pH 3.0 and an adsorbent dose of 1 g/L through the isotherm time of 2 h. Also, temperature elevation could increase the adsorption capacity to 5.7 mg/g. Due to this excellent affinity to adsorb dye at an economic wise rate is shown as a promising candidate for textile dye elimination form aqueous effluent.

Contribution of holothuroids to the bioremediation and stimulation of the benthic microbial metabolism in aquaculture

The implementation of sustainable system designs in aquaculture comprises the biological treatment of pollutants. In order to test the potential of Holothuria (Roweothuria) poli as a candidate for bioremediation of aquaculture wastes, the effect of this species on the benthic microbial activity was studied. Two experimental treatments, with and without holothuroids, were allocated in two benthocosms, each one containing four replicate tanks with undisturbed sediment and a volume of water above it. It was anticipated that H. poli could affect the overall assimilative capacity of the aquaculture effluent system either through the consumption of particulate organic matter or through the stimulation of benthic microbial metabolism. Indeed, the results indicated that the microbial activity related to the mineralization of the N and C was significantly different between the treatments verifying our hypothesis that deposit-feeders that move above or inside the sediment matrix can accelerate the depletion of organic matter through bioturbation.