Solid Fish Waste Research Articles

Sardine Processing Waste: Biological Treatment Strategies and Their Implications

This study explores sustainable methods for Sardine Processing Waste (SPW) valorization. Two approaches were investigated: (a) SPW microbial pretreatment adding Saccharomyces cerevisiae or Bacillus sp. in a two-stage anaerobic digestion (AD) for enzyme and biomethane production and (b) a single-stage AD without SPW pretreatment. Both S. cerevisiae and Bacillus sp. secreted proteases (0.66 and 0.58 U mL−1, respectively) and lipases (3.8 and 4.3 U mL−1, respectively) during hydrolysis, thus reducing viscosity (2.8 and 2.9 cP, respectively) compared with the untreated SPW (4.1 cP). Biomethane production was higher in the single-stage AD (1174 mL CH4 g−1 VS−1) when compared with the two-stage AD (821.5 and 260 mL CH4 g−1 VS−1 with S. cerevisiae and Bacillus sp., respectively). S. cerevisiae addition enhanced SPW degradation as implied by VS and sCOD values (70 and 84%, respectively), but this also resulted in a higher toxicity due to a three-fold increment in NH4-N content, reducing methanogen activity. This research demonstrates the innovative application of S. cerevisiae, a common bread-making yeast, in the biotechnological enhancement of SPW hydrolysis. Non-genetically engineered S. cerevisiae not only co-produced proteases and lipases but also significantly improved solubilization, degradation, and viscosity reduction, thereby rendering the yeast a key player in solid fish waste valorization, beyond its traditional applications.

Valorizing Moroccan crab shells to purify water from Orange G dye: Exploring equilibrium, kinetics, and thermodynamics

A successful approach has been taken to develop a biomaterial derived from fish waste, using Moroccan fish processing by-products from crab shells. Moroccan crab (Portunus pelagicus) shell-derived biomaterial has been developed for wastewater treatment, using marine crustacean waste and addressing the challenges of solid fish waste management. The crab shell powder (CSP) was calcined at 800 °C for three hours and characterized using SEM, EDS, FTIR, and XRD, revealing a predominantly crystalline structure. The CSP's effectiveness as a biosorbent for the removal of the anionic dye Orange G (OG) was assessed under various conditions, including pH, biosorbent mass, temperature, and contact time. Optimal conditions achieved a 98.84 % dye removal rate within 60 min at an adsorbent dose of 0.09 g. The adsorption process adhered to the pseudo-second-order kinetic model and the Freundlich isotherm, indicating a spontaneous, endothermic surface reaction involving multilayer physisorption. The biosorption mechanism is thought to include electrostatic attractions, n-π stacking interactions, hydrogen bonding, and Yoshida hydrogen bonds. The study suggests that CSP is an efficient, eco-friendly adsorbent for industrial wastewater treatment, offering a promising solution for the valorization of fish waste by-products.

Utilization of fish waste as fish meal substitute in formulated fish diet on the growth performance of Nile tilapia fish fry (Oreochromis niloticus)

Fish meal is generally expended as the foremost protein supply in the fish diet. The rising cost of this component inflicted the aquaculture industry to seek a substitute in lessening the pellet cost. Thus, fish waste was tested in this study to investigate its viability. An experiment was performed to study the effects of fish waste and carcass on the growth performance of Nile tilapia fry. Solid fish waste of three different common species available in Mukah’s wet market was formulated into an artificial diet. The diet was formulated into three treatments consist of three protein levels (40%, 45% and 50%) with 4000 kcal/kg energy. A controlled group was fed with a commercial pellet consisting of 45% protein level. Fish were fed at 4% of body weight twice daily for 45 days. Fry reared in a controlled group was discovered highest weight gain, specific growth rate and length gain. There was no significant difference in all treatments for all parameters measured. The lowest weight gain and specific growth rate were recorded in fish fed 45% protein level (T2) group. Fish in T3 (50%) achieved the highest survival rate while T1 (40%) group recorded the lowest. The best and lowest Feed Conversion ratio (FCR) was recorded in the control group. In conclusion, the performance of formulated feed using fish waste is similar to commercial pellet as no significant difference can be observed in all parameters measured.

Novel Liquid Chitosan-Based Biocoagulant for Treatment Optimization of Fish Processing Wastewater from a Moroccan Plant

A novel liquid chitosan-based biocoagulant for treating wastewater from a Moroccan fish processing plant was successfully prepared from shrimp shells (Parapenaeus longirostris), the most abundant fish by-products in the country. The shells were characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Fourier transforms infrared spectroscopy. Using chitosan without adding acetic acid helps to minimize its negative impact on the environment. At the same time, the recovery of marine shellfish represents a promising solution for the management of solid fish waste. In order to test the treatment efficiency of the biocoagulant developed, a qualitative characterization of these effluents was carried out beforehand. The optimization process was conducted in two steps: jar-test experiments and modeling of the experimental results. The first step covered the preliminary assessment to identify the most influential operational parameters (experimental conditions), whereas the second step concerned the study of the effects of three significant operational parameters and their interactions using a Box–Behnken experimental design. The variables involved were the concentration of coagulant (X1), the initial pH (X2), and the temperature (X3) of the wastewater samples, while the responses were the removal rates of turbidity (Y1) and BOD5 (Y2). The regression models and response surface contour plots revealed that chitosan as a liquid biocoagulant was effective in removing turbidity (98%) and BOD5 (53%) during the treatment. The optimal experimental conditions were found to be an alkaline media (pH = 10.5) and a biocoagulant dose of 5.5 mL in 0.5 L of fish processing wastewater maintained at 20 °C.

RESPON PERTUMBUHAN TANAMAN KEDELAI (Glycine max L. Merril) DENGAN PEMBERIAN POC LIMBAH IKAN DAN SOLID

Soybean is an important food crop after rice and maize. Soybean production in East Kalimantan based on the estimated 2014 rate is estimated at 1,263 tons of dry seeds. Compared to 2013 production there was a decrease of 139 tons (9.91%) (BPS, 2014). The low productivity is because soybean cultivation is still not optimal. One of the cultivation that can be done is by using Fish Waste and Solid POC. The purpose of this study was to determine the growth response of soybean (Glycine max l. Merril) by giving poc fish waste and solids. This research was conducted in Sidorejo Hamlet, Bilah Hilir District, Labuhan Batu Regency, North Sumatra Province. The research method used was factorial randomized block design (RBD) consisting of 2 factors, 9 combinations and 3 replications. The first factor was the provision of POC fish waste (P) consisting of 3 levels, namely: P0 = 0 ml / planting hole, P1 = 100 ml / planting hole, P2 = 200 ml / planting hole. The second factor is the provision of solid (S) consisting of 3 levels, namely: S0 = 0 ml / planting hole, S1: 100 ml / planting hole, S2: 200 ml / planting hole. Parameters observed were plant height, number of leaves, leaf width and stem diameter. Based on the results of research in the field, it shows that the provision of fish waste poc and solid has no significant effect on all observed parameters. Meanwhile, the interaction between poc and solid fish waste also had no significant effect on all observed parameters. Keywords: Soybean, POC Fish Waste, and Solid

Organic Matter Composition and Phosphorus Speciation of Solid Waste from an African Catfish Recirculating Aquaculture System

Recycling of phosphorus (P) from feed input in aquaculture systems gains increasing importance, especially relating to sustainable agriculture and food production. In order to find possible areas of application of African catfish solid waste, the purpose of this study was to characterize the elemental and organic matter composition and P speciation in the aquaculture fish waste. Pyrolysis-field ionization mass spectrometry (Py-FIMS) was used to investigate the composition of organic matter and P K-edge X-ray absorption near edge structure (XANES) spectroscopy to describe the occurring P-containing compounds in African catfish solid waste from an intensive recirculation aquaculture system (RAS). The solid fish waste was mainly composed of sterols, free fatty acids and alkylaromatics, as it is common for digestive systems of animals. Ingredients such as the phytosterol beta-sitosterin confirm plant-based feed ingredients and some recalcitrance against digestion in the African catfish gut. The P in the solid fish waste was exclusively bound as calcium-phosphates. These calcium-phosphate minerals as major constituents of African catfish waste may have beneficial effects when applied to soils, suggesting the use of this waste as possible soil amendment in the future.

Fish visceral protease – an alternative source for recovery of silver from waste X ray photographic films

Fish processing in India generates enormous amount of solid fish waste and causes various kinds of pollutions. Actually these wastes are used for the production of a variety of value added products such as enzymes mainly protease. Protease enzyme has diverse applications in a wide variety of industries such as detergent, food, pharmaceutical and leather industries, peptide synthesis and for the recovery of silver from used X-ray films. In this paper, Labeo rohita fish visceral waste was collected from Mettur Dam, Tamil Nadu. A crude homogenate was prepared and the protease activity was confirmed by zymography. After that an experiment was carried out with the isolated crude protease to prove its efficiency to recover silver from waste X ray photographic films.

Single-Sludge Denitrification in Recirculating Aquaculture Systems: Effects of Pre-Fermentation and pH

<abstract> Single-sludge denitrification (DN) reactors in aquaculture use the carbonous solid fish waste produced in the system to reduce the discharged nitrate load. The solid waste is available for denitrifiers when present in soluble, readily biodegradable form, and the transformation is accomplished by bacterial hydrolysis and fermentation. The objective of this study was to quantify the effect of pre-fermentation of solid fish waste on single-sludge DN reactor efficiency. Pre-fermentation times tested were 0 d (no pre-fermentation), 1 d, 5 d, and 10 d, and the efficiency was quantified as the potential DN rate obtained in laboratory assays. Results showed that the highest DN rate was achieved with 1 d pre-fermentation. The volumetric DN rates measured in decreasing order were 23.4 ±0.00 mg NO₃-N L^-1 h^-1 (1 d), 20.5 ±0.35 mg NO₃-N L^-1 h^-1 (5 d), 17.0 ±0.47 mg NO₃-N L^-1 h^-1 (10 d), and 14.2 ±0.24 mg NO₃-N L^-1 h^-1 (0 d). It was suspected that the poor utilization of soluble COD (sCOD) in the 5 d and 10 d pre-fermentation treatments was due to the low starting pH (pH < 7). Subsequently, the experiments were repeated in 0.1 M HEPES buffer (pH = 7.1) and showed a clear correlation between specific DN rate and sCOD content. Overall, the highest increase in potential specific DN rate was achieved by applying pre-fermentation; e.g., from 0 d to 1 d, the increase was 123% and 106% at unadjusted pH and pH 7.1, respectively. An additional 20% increase was achieved at pH 7.1 by prolonging the pre-fermentation time to 5 d.

Removal of geosmin and 2-methylisoborneol by bioflocs produced with aquaculture waste

Geosmin and 2-methylisoborneol (MIB) are two of the most common odorous compounds that critically affect the quality of fish. In the current study, the solid fish waste from a recirculating aquaculture system (RAS) was used as the substrate to produce bioflocs in suspended growth reactors (SGRs). The removal efficiency of geosmin and MIB by the bioflocs was investigated under in situ and in vitro conditions. The highest removal rates for geosmin and MIB in the SGRs were 187.00 ± 0.23 and 170.91 ng L−1 d−1, respectively. Under the in vitro experimental conditions, 90.30 % of the geosmin and 72.93 % of the MIB were removed from the aqueous phase by the bioflocs within 48 h of incubation. It was found that the decay of these odorous compounds by the bioflocs was mediated by both chemical/physical sorption and biological degradation. Moreover, the addition of these odorous compounds did not affect the treatment efficiency of the reactors and had no adverse influence on the crude protein content of the bioflocs. Thus, using biofloc technology (BFT), SGRs can be used to reuse the nitrogen in fish waste and to remove geosmin and MIB from the culture water efficiently.

Evaluation nutritional of acid silage of Nile tilapia (Oreochromis niloticus), whole fish discarded, farmed in Indaiatuba - SP

The continental aquaculture with a production of 210,644,500 thousand tonnes produces a volume of solid waste causing a serious environmental problem, where 20% of the fish caught gets lost for lack of storage. The ideal would be to use raw materials and to recover byproducts as ingredients for animal feed. Aiming to increase the income and the capacity of production and, thus, to minimize environmental and health problems, deriving from fish waste, it was prepared the acid silage of the whole fish discarded from Nile tilapia ( Oreocrhromis niloticus ) after acidification and homogenisation of the biomass with 3% of formic acid and maintaining the pH around 3.7. Analyses were conducted to determine the humidity, protein, lipids and ash. Amino acids were examined in an auto-analyzer after acid hydrolysis, except for tryptophan determined by colorimetry. The new silage of Nile tilapia showed values higher than FAO standards for all essential amino acids, except for tryptophan. The highest values ​​were found for glutamic acid, aspartic acid, lysine, leucine and glycine. The results indicate the potential use of the acid silage, prepared from the whole fish discarded from Nile tilapia, as a protein source in the formulation of animal feed, turning it into an excellent alternative for adding value to biowaste deriving from solid fish waste.

Evaluation of the biomethane potential of solid fish waste

Manufacturing processes in fish canning industries generate a considerable amount of solid waste that can be digested anaerobically. The aim of this research was to study the biochemical methane potential of different solid fish waste. For tuna, sardine and needle fish waste, around 0.47g COD–CH4/g CODadded was obtained in batch experiments with 1%TS; whereas for mackerel waste, the methane production attained 0.59g COD–CH4/g CODadded. The increase in the waste/inoculum ratio, from 1.1–1.3 to 2.8–3.3g VSwaste/g VSinoculum, led to overload due to VFA and LCFA accumulation. Afterward, co-digestion assays of fish waste with gorse were undertaken but the biochemical methane potential did not improve.

Extraction, Purification and Characterization of Fish Chymotrypsin: A Review

Problem statement: Solid fish waste is generated from the unwanted parts of fish including heads, tails, fins, frames, offal (guts, kidney and liver) and skin. It accounts for up to 80% of material from production of surimi, 66% from production of fillet and 27% from production of headed and gutted fish. Currently, fish wastes are disposed off in land-based waste disposal systems or at sea generating toxic by-products during the decomposition process. However, fish processing waste can be used to produce commercially valuable by-products, such as chymotrypsin. Approach: A comperehensive review of the literature on the extraction, purification and characeterization of fish chymotrypsin was performed. Results: Chymotrypsin is an endopeptidase secreted by the pancreatic tissues of vertebrates and invertebrates. It has 3 different structures (chymotrypsin A, B and C) varying slightly in solubility, electrophoretic mobility, isoelectric point and cleavage specificity. Only chymotrypsin A and B are found in fish. Compared with mammal chymotrypsin, fish chymotrypsins have similar amino acid composition and molecular weights. Fish chymotrypsins have higher specific activity, especially those from cold-water fish, and low pH and temperature tolerance. The factors affecting the concentration and activity of chymotrypsin in fish are water temperature, fish species, fish age, fish weight and starvation. Chymotrypsin has application in various industries including the food industry, leather production industry chemical industry and medical industry. Conclusion: Extraction techniques for chymotrypsin include: ultra-filtration, ammonium sulphate fractionation precipitation or water-in-oil microemulsions. Purification can be carried out using re-crystallization and gel-filtration, ion-exchange and hydrophobic interaction chromatography. Further studies should focus on the optimization of purifiying chymotrypsin from fish processing wastes.

Effect of a Parabolic Screen Filter on Water Quality and Production of Nile Tilapia (Oreochromis niloticus) and Water Spinach (Ipomoea aquatica) in a Recirculating Raft Aquaponic System

Aquaponics is an integrated fish and plant recirculating production system. Solid fish waste must be removed from the production system to maintain optimal water quality parameters for fish and plant health. The University of the Virgin Islands (UVI) raft aquaponic system’s primary treatment device for solids removal is a cylindro-conical clarifier; however, alternative mechanical filtration devices such as a parabolic screen filter (PSF) may offer advantages. The objectives of the elevenweek experiment were to compare water quality parameters, Nile tilapia (Oreochromis niloticus) production and water spinach (Ipomoea aquatica) production in a raft aquaponic system using either a cylindroconical clarifier or parabolic screen filter for primary treatment of solids in the waste stream.

Heterotrophic bacterial production on solid fish waste: TAN and nitrate as nitrogen source under practical RAS conditions

The drumfilter effluent from a recirculation aquaculture system (RAS) can be used as substrate for heterotrophic bacteria production. This biomass can be re-used as aquatic feed. RAS effluents are rich in nitrate and low in total ammonia nitrogen (TAN). This might result in 20% lower bacteria yields, because nitrate conversion into bacteria is less energy efficient than TAN conversion. In this study the influence of TAN concentrations (1, 12, 98, 193, 257 mg TAN/l) and stable nitrate-N concentrations (174 ± 29 mg/l) on bacteria yields and nitrogen conversions was investigated in a RAS under practical conditions. The effluent slurry was supplemented with 1.7 g C/l sodium acetate, due to carbon deficiency, and was converted continuously in a suspended bacteria growth reactor (hydraulic retention time 6 h). TAN utilization did not result in significantly different observed yields than nitrate (0.24–0.32 g VSS/g C, p = 0.763). However, TAN was preferred compared to nitrate and was converted to nearly 100%, independently of TAN concentrations. TAN and nitrate conversions rates were differing significantly for increasing TAN levels ( p < 0.000 and p = 0.012), and were negatively correlated. It seems, therefore, equally possible to supply the nitrogenous substrate for bacteria conversion as nitrate and not as TAN. The bacteria reactor can, as a result, be integrated into an existing RAS as end of pipe treatment.

Molasses as C source for heterotrophic bacteria production on solid fish waste

The drumfilter effluent from a recirculation aquaculture system (RAS) can be used as substrate for heterotrophic bacteria production. These bacteria can be reused as aquatic feed. In RAS drumfilter effluents are organic carbon deficient for bacteria production. This is due to nitrogen accumulation in the system water. In the present experiment, a bacteria growth reactor (3.5l) was connected to the drumfilter (filter mesh size 60 μm) outlet of a recirculation system. To counteract carbon deficiency, different supplementation levels of molasses (organic carbon) were tested (carbon fluxes of 0.0, 3.2, 5.8, 7.8, 9.7 gC molasses/l/d; C:N ratios: 3.4, 6.4, 9.4, 13.0 and 16.5). The hydraulic retention time in the bacteria reactor was 6 h. For the maximum flux, the VSS and crude protein productions were about 168 gVSS and 95 g crude protein per kg feed. The maximum conversion of nitrate and ortho-phosphate was 24 g NO 3−N and 4 gP/kg feed. This equals a conversion of 90% of the inorganic nitrogenous waste and 98% of the ortho-phosphate–P. Furthermore the maximum substrate removal rate and the K s for molasses were determined (1.62 gC/l/h and 0.097 gC/l respectively). The maximum specific removal rate was 0.31 gC/gVSS/h and the related half saturation constant was 0.008 gC/l. The observed growth rate reached a maximum for C fluxes higher than 8 g/l/d. The present integration of heterotrophic bacteria production in RAS represents, therefore, an innovative option to reduce waste discharge by conversion. If the bacteria are reused as feed, system's ecological sustainability increases.

Analysis of nutrient flows in integrated intensive aquaculture systems

This paper analyses nutrient conversions, which are taking place in integrated intensive aquaculture systems. In these systems fish is cultured next to other organisms, which are converting otherwise discharged nutrients into valuable products. These conversions are analyzed based on nitrogen and phosphorous balances using a mass balance approach. The analytical concept of this review comprises a hypothetical system design with five modules: (1) the conversion of feed nutrients into fish biomass, the “Fish-Biomass-Converter”; (2) the separation of solid and dissolved fish waste/nutrients; the “Fish-Waste-Processor”; (3) the conversion of dissolved fish waste/nutrients, the “Phototrophic-herbivore-Converter”; (4 and 5) the conversion of solid fish waste, the “Bacterial-Waste-Converter”, or the “Detrivorous-Converter”. In the reviewed examples, fish culture alone retains 20–50% feed nitrogen (N) and 15–65% feed phosphorous (P). The combination of fish culture with phototrophic conversion increases nutrient retention of feed N by 15–50% and feed P by up to 53%. If in addition herbivore consumption is included, nutrient retention decreases by 60–85% feed N and 50–90% feed P. This is according to the general observation of nutrient losses from one trophic level to the next. The conversion of nutrients into bacteria and detrivorous worm biomass contributes only in smaller margins (e.g. 7% feed N and 6% feed P and 0.06% feed N 0.03 × 10 −3% feed P, respectively). All integrated modules have their specific limitations, which are related to uptake kinetics, nutrient preference, unwanted conversion processes and abiotic factors.

The Chemical Composition of Settleable Solid Fish Waste (Manure) from Commercial Rainbow Trout Farms in Ontario, Canada

The chemical composition of settleable faecal fish waste was determined from fresh manure samples collected at 12 commercial farms growing rainbow trout Oncorhynchus mykiss in Ontario, Canada. The manure samples from the commercial farms averaged 2.83% nitrogen (N), 2.54% phosphorus (P), 0.10% potassium (K), 6.99% calcium (Ca), and 0.53% magnesium (Mg) on a dry-weight basis. The concentrations of the metals, arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), iron (Fe), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), selenium (Se), and zinc (Zn) were also measured. Mean concentrations of these metals ranged from 0.05 mg/kg for Hg to 1,942 mg/kg for Fe. Fresh fish manure has similar levels of N, P, Ca, and Mg, and lower levels of K when compared to manure from beef, dairy cattle, poultry and swine. Fish manure tended to have a higher content of Mn, Cd, Cr, Pb, Fe, and Zn than most other livestock manures, but had lower levels of As, Se, Co, and Ni. The copper (Cu) content of fish manure was similar to all other livestock manures. The results from this study indicate that fresh fish manure is similar in its chemical composition to other livestock manures, and should be suitable for use as an agricultural fertilizer. In addition, it is hoped that these data will also help regulatory agencies and farmers make sensible and pragmatic decisions concerning the appropriate and safe disposal of manure wastes collected from land-based trout culture facilities.