Explore the vast range of titles available.

The excessive reliance on fossil fuels has resulted in an energy crisis, environmental pollution, and health problems, calling for alternative fuels such as biodiesel. Here, we review computational chemistry and machine learning for optimizing biodiesel production from waste. This article presents computational and machine learning techniques, biodiesel characteristics, transesterification, waste materials, and policies encouraging biodiesel production from waste. Computational techniques are applied to catalyst design and deactivation, reaction and reactor optimization, stability assessment, waste feedstock analysis, process scale-up, reaction mechanims, and molecular dynamics simulation. Waste feedstock comprise cooking oil, animal fat, vegetable oil, algae, fish waste, municipal solid waste and sewage sludge. Waste cooking oil represents about 10% of global biodiesel production, and restaurants alone produce over 1,000,000 m3 of waste vegetable oil annual. Microalgae produces 250 times more oil per acre than soybeans and 7–31 times more oil than palm oil. Transesterification of food waste lipids can produce biodiesel with a 100% yield. Sewage sludge represents a significant biomass waste that can contribute to renewable energy production.

The inadequate management of fish processing waste or by-products is one of the major problems that fish industry has to face nowadays. The mismanagement of this raw material leads to economic loss and environmental problems. The demand for the use of these by-products has led to the development of several processes in order to recover biomolecules from fish by-products. An efficient way to add value to fish waste protein is protein hydrolysis. Protein hydrolysates improve the functional properties and allow the release of peptides of different sizes with several bioactivities such as antioxidant, antimicrobial, antihypertensive, anti-inflammatory, or antihyperglycemic among others. This paper reviews different methods for the production of protein hydrolysates as well as current research about several fish by-products protein hydrolysates bioactive properties, aiming the dual objective: adding value to these underutilized by-products and minimizing their negative impact on the environment.

Developing peptide-based drugs are very promising to address many of the lifestyle mediated diseases which are prevalent in a major portion of the global population. As an alternative to synthetic peptide-based drugs, derived peptides from natural sources have gained a greater attention in the last two decades. Aquatic organisms including plants, fish and shellfish are known as a rich reservoir of parent protein molecules which can offer novel sequences of amino acids in peptides, having unique bio-functional properties upon hydrolyzing with proteases from different sources. However, rather than exploiting fish and shellfish stocks which are already under pressure due to overexploitation, the processing discards, regarded as secondary raw material, could be a potential choice for peptide based therapeutic development strategies. In this connection, we have attempted to review the scientific reports in this area of research that deal with some of the well-established bioactive properties, such as antihypertensive, anti-oxidative, anti-coagulative, antibacterial and anticarcinogenic properties, with reference to the type of enzymes, substrate used, degree of particular bio-functionality, mechanism, and wherever possible, the active amino acid sequences in peptides. Many of the studies have been conducted on hydrolysate (crude mixture of peptides) enriched with low molecular bioactive peptides. In vitro and in vivo experiments on the potency of bioactive peptides to modulate the human physiological functions beneficially have demonstrated that these peptides can be used in the prevention and treatment of non-communicable lifestyle mediated diseases. The information synthesized under this review could serve as a point of reference to drive further research on and development of functionally active therapeutic natural peptides. Availability of such scientific information is expected to open up new zones of investigation for adding value to underutilized secondary raw materials, which in turn paves the way for sustainability in fish processing. However, there are significant challenges ahead in exploring the fish waste as a source of bioactive peptides, as it demands more studies on mechanisms and structure–function relationship understanding as well as clearance from regulatory and statutory bodies before reaching the end user in the form of supplement or therapeutics.

The market demand for marine-based cosmetics has shown a tremendous growth rate in the last decade. Marine resources represent a promising source of novel bioactive compounds for new cosmetic ingredient development. However, concern about sustainability also becomes an issue that should be considered in developing cosmetic ingredients. The fisheries industry (e.g., fishing, farming, and processing) generates large amounts of leftovers containing valuable substances, which are potent sources of cosmeceutical ingredients. Several bioactive substances could be extracted from the marine by-product that can be utilized as a potent ingredient to develop cosmetics products. Those bioactive substances (e.g., collagen from fish waste and chitin from crustacean waste) could be utilized as anti-photoaging, anti-wrinkle, skin barrier, and hair care products. From this perspective, this review aims to approach the potential active ingredients derived from marine by-products for cosmetics and discuss the possible activity of those active ingredients in promoting human beauty. In addition, this review also covers the prospect and challenge of using marine by-products toward the emerging concept of sustainable blue cosmetics.

The current research is primarily oriented on determining the influence of marine fish waste (MFW) oil biodiesel catalyzed with calcined eggshell heterogeneous base catalyst (ESBD) and its blends on two-cylinder four-stroke diesel engine. The physicochemical and fuel properties such as free fatty acid content (0–0.25%), acid value (0–0.5 mg KOH/g), viscosity (3.33–5.88 cP), flash point (57–115 °C), calorific value (39,287- 42,906 kJ/kg), cold filter plugging point (8- -11 °C) and cetane number (33.9–57.8) for B5, B20, and B50 blends of ESBD authenticates their application in the diesel engine. The B5, B20, B50, and B80 ESBD-diesel fuel blends exhibited brake specific fuel consumption value in the 0.21–0.23 kgs/kWh range and brake thermal efficiency in 31.59–36.29% range at 100% engine load, slightly higher than diesel. The B80 ESBD blends displayed the highest in-cylinder pressure (55.90 bars) and heat release rate (69.82 J/deg). Across all ESBD blends, 59.34–70.32%, 2.57–6.90%, and 12.40–27.35% reductions in CO, CO 2 , and HC emissions were observed. B50 ESBD blend showed a 69.23% and 27.35% reduction in CO and HC emissions than diesel, respectively. The B80 blend showed a 19.51% increase in O 2 emission than diesel. The key finding of the current research unveils that the exploitation of ESBD blends in diesel engines could aid in better combustion and reduce greenhouse gas emissions. The exploitation of MFWs for biodiesel production using calcined eggshell catalyst would aid in overcoming waste disposal issues, reduce environmental pollution, and also provide additional revenue to fish farmer communities and the fisheries sector.

Fish wastes offer tremendous unexploited potential for value adding for such materials, collagen, gelatin, and hydrolysate. Additionally, fish waste may be suitable for the production of bioactive peptides that exhibit strong antihypertensive, antioxidative, and anticancer activities. This paper reviews the production of purified bioactive peptides from various fish waste protein hydrolysates via enzymatic hydrolysis after enzyme screening and optimization. The purification of bioactive peptides is carried out using ultra- and gel filtration as well as the RP-HPLC method. Purified peptide characterizations in terms of molecular weight, amino acid sequence, and composition are also provided, illustrating that peptides with low molecular weight and short amino acid sequences are more potent as bioactive peptides. Hence, further studies are encouraged to examine the bioactivity and bioavailability of protein peptides derived from fish wastes, especially those with anticancer characteristics.

Numerous technological innovations have been developed for managing post-industrial soils, but assisted phytostabilization–a sustainable and environmentally friendly approach–has attracted significant global interest. This study evaluates the effectiveness of a novel biocomposite, composed of fish waste compost and chalcedonite, in assisting the phytostabilization of soil contaminated with potentially toxic elements (PTEs), using Lolium perenne L. (perennial ryegrass) as a test plant. The results demonstrated that the biocomposite significantly increased soil pH (by 0.19 units), organic carbon content (by 174.3%), improving soil fertility by increasing nutrient availability (available P by 219.6%, and available K by 146.9%), and plant growth. Additionally, it promoted PTE accumulation in the roots while reducing Pb (44%), Zn (24%), Cu (23%), and Ni (14%) concentrations in the aerial parts, as well as Cd (71%), Ni (33%), and Cu (29%) levels in the soil. The biocomposite also altered the fractionation of PTEs, reducing their mobility and bioavailability. Specifically, it decreased the exchangeable fraction (F1) by 45% for Cu, 71% for Cd, 41% for Pb, and 24% for Zn, effectively limiting their environmental risk. Moreover, it promoted the redistribution of Pb and Zn into the reducible fraction (F2), Cu and Pb into the oxidizable fraction (F3), and Cu, Ni, and Cd into the residual fraction (F4), indicating enhanced stabilization. The highest immobilization efficiencies were observed for Cd (53.9%) and Pb (52.3%), confirming the biocomposite’s effectiveness in reducing PTE mobility. These findings highlight the potential of biocomposite amendments in remediating PTE-contaminated soil by improving soil physicochemical properties, reducing PTE bioavailability, and enhancing phytostabilization efficiency. This approach supports sustainable waste valorization and circular economy principles, offering a promising strategy for rehabilitating post-industrial lands with high PTE contamination.

Basa ( Pangasius bocourti ) fish is commonly used in fish fillet industry and it generates 75% of waste that causes environmental pollution. However, this waste is a rich source of nutrients and fatty acids. In the present work, analyses of Basa fish waste oil showed high contents of oleic acid (45.15%), linoleic (11.31%) and alpha linolenic acid (0.52%). Hence safe pet foods as powder and kibble forms were prepared utilizing Basa fish waste and using γ-irradiation, known to be promising technology for extension of shelf life of food. Microbiological and lipid peroxidation analyses, showed an extended shelf-life of 65 days for both the pet foods when irradiated at 2.5 kGy whereas, non-irradiated kibble and powder samples spoiled within 28 and 35 days respectively. No significant changes in proximate composition of these pet foods were observed on irradiation. Graphical Abstract

Fish wastes pose environmental and economic challenges for companies operating in the field. The global fishing industry generates a substantial amount of waste, which has far-reaching consequences. Just to have a glance of the issue on a global scale, according to the Food and Agriculture Organization of the United Nations (FAO), nearly 50 million tons of fish are wasted every year, representing about 30% of the total global catch. The majority of this waste occurs at sea, where fish are discarded as by-catch or are not fully utilized; waste also occurs during processing, transportation, and retail. While the waste management costs continue to rise, these by-products also present an untapped potential in the form of valuable bioactive compounds. Some of the noteworthy compounds found in fish wastes include Omega-3 fatty acids ( ω -3), collagen, and hyaluronic acid, all of which have substantial commercial value. The extraction of high-value compounds from fish waste is a promising way to reduce waste and create new products that can benefit human health and the environment. The full valorization of wastes and biomass is reached in biorefinery plants, where the combination of innovative separation technologies and reaction stages allows extracting high-quality final products with a very low impact on the environment. In this framework, we propose a novel process to extract ω -3 from fish wastes while keeping their integrity for further protein (collagen) extraction and improving the ω -3 quality compared to traditional thermal extraction systems. The process is designed using a feedstock derived from salmonid wastes and includes extraction using Supercritical Fluid (SCF)- C O 2 , followed by hydrolysis and vacuum distillation. We simulated the innovative process in Aspen Plus, a professional tool for chemical process design, providing key indications regarding the process feasibility (yields, flow concentrations, and basic equipment design). The process has been optimized with respect to recovery ratio, purity, and energy duties, providing a clear profile regarding the technical feasibility of the innovative process. Results show good efficiency of the proposed process, with a recovery of 96% and a purity of 77%, in good compliance with other green applications, such as pretreatment-assisted enzymatic extraction. According to detailed results on the final composition of products, the simulations have reported a very high ratio ω 3 / ω 6 , corresponding to recognized highly beneficial effects on health. All in all, the presented research demonstrates through quantitative data the feasibility of ω -3 production and provides a tangible instance highlighting how the circular economy paradigm can foster innovation within the agri-food industry. This is accomplished by utilizing technological solutions that have minimal environmental impact and emissions. Graphical abstract

This study explores the feasibility of fish waste as the potential source of fish oil, which could be used as fatliquoring agent in leather processing. The fish oil was extracted from fish waste with a yield of 39.8 g/1000 g of sample on wet basis and converted into fatliquor by a sulphation process using sulphuric acid. The average particle size and particle dispersion index (PDI) of the fish oil fatliquor were determined to be 82.4 nm and 0.508, respectively, which implied that the fish oil fatliquor could penetrate the leather easily. Fish oil fat liquor emulsions prepared with water in 1:9 dilutions showed good stability after 24 h. Scanning electron microscope (SEM) analysis revealed that leather processed with the fish oil fatliquor exhibited a soft grain without any fatty-spew, which demonstrated easy penetration into the inner fibers of leather. The physical and mechanical properties of the leather lubricated with the sulphated fish oil fat were better than those processed using the commercial fatliquoring agent. It was also observed that pollution load such as chemical and biochemical oxygen demand of effluent from the fatliqouring process reduced significantly. This implied that the sulphated fatliquor derived from fish waste would be an eco-friendly alternative to traditional fatliquors used in tanneries. Graphic Abstract