Bioprocessing of Shrimp Waste Using Novel Industrial By-Products: Effects on Nutrients and Lipophilic Antioxidants

The production of marine foods is on the rise, and shrimp is one of the most widely consumed. As a result, a considerable amount of shrimp waste is generated, becoming a hazardous problem. Shrimp waste is a rich source of added-value components such as proteins, lipids, chitin, minerals, and carotenoids; however, new bioprocesses are needed to obtain these components. This work aimed to characterize the chemical and nutraceutical constituents from the liquor of shrimp waste recovered during a lactic acid fermentation process using the novel substrate sources whey and molasses. Our results showed that the lyophilized liquor is a rich source of proteins (25.40 ± 0.67%), carbohydrates (38.92 ± 0.19%), minerals (calcium and potassium), saturated fatty acids (palmitic, stearic, myristic and lauric acids), unsaturated fatty acids (oleic acid, linoleic, and palmitoleic acids), and astaxanthin (0.50 ± 0.02 µg astaxanthin/g). Moreover, fermentation is a bioprocess that allowed us to obtain antioxidants such as carotenoids with an antioxidant capacity of 154.43 ± 4.73 µM Trolox equivalent/g evaluated by the ABTS method. Our study showed that liquor from shrimp waste fermentation could be a source of nutraceutical constituents with pharmaceutical applications. However, further studies are needed to separate these added-value components from the liquor matrix.

Bioconversion of Shrimp Waste with Fermentation Stage Process on Proximate Analysis and Digestibility Values of Feed

Frozen shrimp processing waste has the potential to be used as feed, but the characteristics of the shrimp shells need to be improved so that they can be digested. Fermentation using three types of microbes in stages has been studied, to determine the optimal processing time that yields proximate values and protein digestibility of shrimp waste concentrate. Completely randomized design (CRD), 3 treatments and 7 replications, conducted with treatments of shrimp waste bioconversion in stage over time, T1 = Bacillus licheniformis (Bl.) 1 day + Lactobacillus sp. (Ls.) 1 day; + Saccharomyces cerevisiae (Sc) 1 day; T2 = Bl. 2 days + Ls. 2 days + Sc = 2 days; T3 = Bl. 3 days + Ls. 3 days + Sc = 3 days. Product of shrimp waste bioconversion was used as a nutrient concentrate in dietary of local poultry (CP 15%, ME 2750 kcal/kg). The best proximate analysis value showed that each stage overtime two days of bioconversion with Bacillus licheniformis, followed by Lactobacillus sp. and finally fermented by Saccharomyces cerevisiae. The proximate analysis resulted that the Crude Protein of product bioconversion was 48.5%. Extract ether, Calcium and Phosphorous contents respectively were 7.81%, 7.57% and 3.14%. The best value of digestibility of protein feed containing bioconversion product of concentrations of local poultry was 72.91%.

Application of local microorganisms from tuna fish and shrimp waste as bio activator for household organic waste composting by Takakura method

Organic waste has the potency to use as bio activator material. This research compares household organic waste compost results with the addition of bio activator from local microorganism activator (LMO) from tuna fish and shrimp waste with Effective Microorganisms (EM4). The composting method used is aerobic composting with the Takakura composting technique. This composting is carried out in 5 variations, variation one without-bio activator added, 2 with LMO of tuna fish waste added, variation 3 with LMO shrimp waste added, variation 4 with LMO of tuna fish, and shrimp waste added, variation 5 with EM4 added. Analysis of all compost quality has met SNI 19-7030-2004 standards. A total of 2 kg of raw material produced solid compost becomes 0.7-1 kg of compost. The use of bio activators can speed up the composting process to 8-12 days. The variation of adding LMO tuna fish waste was chosen as a suitable alternative compared to other variations. The composting process with LMO of tuna fish waste results from the fastest composting time of 9 days with a C/N ratio of 18.45%, P2O5 0.56 %, and 0.76% K2O, with 0.85 kg of compost. Scoring results in variation 2 is the best variation in compost maturity quality.

Proteases Production and Chitin Preparation from the Liquid Fermentation of Chitinous Fishery By-Products by Paenibacillus elgii

Chitinous fishery by-products have great application in the production of various bioactive compounds. In this study, Paenibacillus elgii TKU051, a protease-producing bacterial strain, was isolated using a medium containing 1% squid pens powder (SPP) as the sole carbon/nitrogen (C/N) source. P. elgii TKU051 was found to produce at least four proteases with molecular weights of 100 kDa, 57 kDa, 43 kDa, and 34 kDa (determined by the gelatin zymography method). A P. elgii TkU051 crude enzyme cocktail was optimally active at pH 6–7 and 60 °C. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and α-glucosidase inhibitory activity of the hydrolysates obtained from the hydrolysis of shrimp shell powder, shrimp head powder, shrimp meat powder, fish head powder and soya bean powder catalyzed by the P. elgii TkU051 crude enzyme cocktail were also evaluated. P. elgii TKU051 exhibited a high deproteinization capacity (over 94%) on different kinds of shrimp waste (shrimp heads and shells; fresh and cooked shrimp waste; shrimp waste dried by oven and lyophilizer), and the Fourier-transform infrared spectroscopy profile of the chitin obtained from the deproteinization process displayed the characteristic of chitin. Finally, the obtained chitin exhibited an effect comparable to commercial chitin in terms of adsorption against Congo Red (90.48% and 90.91%, respectively). Thus, P. elgii TKU051 showed potential in the reclamation of chitinous fishery by-products for proteases production and chitin extraction.

Synthesis and Physicochemical Characteristics of Chitosan-Based Polyurethane Flexible Foams

The use of shrimp waste to obtain chitosan (Ch) is an essential issue, considering a circular economy, waste management, and its application to environmentally friendly materials. In this study, northern prawn shells were utilized to obtain Ch, which could then be used for synthesizing chitosan-based polyurethane (PUR+Ch) foams with different Ch concentration. The chemical structure, morphology, hardness, thermal properties, viscoelastic properties, and sorption properties in relation to oil and water of these materials were determined. The results present that the addition of Ch into PUR influences the physicochemical characteristics and properties of the tested materials. PUR+Ch foams with 1–3 wt% Ch had more open cells and were softer than neat PUR. PUR+Ch1 had the best thermal properties. PUR+Ch2 foam with 2 wt% Ch as a whole was characterized as having the highest water sorption. The PUR+Ch1 foam with 1 wt% Ch had the best oil sorption. This paper shows that the modification of PUR by Ch is a very promising solution, and PUR+Ch foams can be applied in the water treatment of oil spills, which can be dangerous to the water environment.

Valorization of Fermented Shrimp Waste with Supercritical CO2 Conditions: Extraction of Astaxanthin and Effect of Simulated Gastrointestinal Digestion on Its Antioxidant Capacity

Lactic acid fermentation increases the bioactive properties of shrimp waste. Astaxanthin is the principal carotenoid present in shrimp waste, which can be found esterified in the liquid fraction (liquor) after its lactic acid fermentation. Supercritical CO2 technology has been proposed as a green alternative to obtain astaxanthin from fermented shrimp waste. This study aimed to optimize astaxanthin extraction by supercritical CO2 technology from fermented liquor of shrimp waste and study bioaccessibility using simulated gastrointestinal digestion (GD) of the optimized extract. A Box–Behnken design with three variables (pressure, temperature, and flow rate) was used to optimize the supercritical CO2 extraction. The optimized CO2 extract was obtained at 300 bar, 60 °C, and 6 mL/min, and the estimated characteristics showed a predictive extraction yield of 11.17%, antioxidant capacity of 1.965 mmol of Trolox equivalent (TE)/g, and astaxanthin concentration of 0.6353 µg/g. The experiment with optimal conditions performed to validate the predicted values showed an extraction yield of 12.62%, an antioxidant capacity of 1.784 mmol TE/g, and an astaxanthin concentration of 0.52 µg/g. The astaxanthin concentration decreased, and the antioxidant capacity of the optimized extract increased during gastrointestinal digestion. In conclusion, our optimized supercritical CO2 process is suitable for obtaining astaxanthin from shrimp by-products after lactic acid fermentation.

Increasing the abundance of microorganisms in a regosol soil using biopelet fertilizer composed from biochar, chicken manure, and shrimp waste to increase soil fertility

Results of previous research have proven that soil organic matter (humic and biochar compounds) can increase and maintain soil fertility and protect environmental resilience. The purpose of this study was to increase the abundance of microorganisms in young soil (regosol) with biopelet fertilizer composed of a combination of biochar, chicken manure, and shrimp waste to improve soil fertility. The experimental design used was a randomized block design with two factors, namely the composition and dosage of biopelets. The compositions of biopelet were 70% biochar, 15% chicken manure and 15% fish waste (B1); 50% biochar, 25% chicken manure and 25 % fish waste (B2): and 20% biochar, 40% chicken manure and 40% fish waste (B3). The dosage used was four levels (0, 2.5, 5, and 10 t/ha).The results showed that the application of biopelet fertilizer to the regosol soil reduced soil pH from slightly alkaline to near neutral, and the addition of up to 10 t biopelet/ha increased soil organic C content from 1.17% to 1.72%, as well as increasing the availability of N, P, and K nutrients. Improvement in pH, organic-C, and soil macronutrients was followed by an increase in the abundance of soil microorganisms, especially bacteria.

Application of Shrimp Waste for the Synthesis of Polyurethane–Chitosan Materials with Potential Use in Sorption of Oil Micro-Spills in Water Treatment

Shrimp waste is a common waste in seafood processing. It is used as part of the fish meal which is added to feed. Bearing in mind the Green Deal and sustainability development, it was proposed to use northern prawn shells to obtain chitosan (Ch), which could then be used for polyurethane (PUR) modification. In ports, oil micro-spills often flow into the waters of gulfs and, consequently, into the sea. Systematic chemical and petroleum water pollution may pose a threat to flora and fauna. In this study, chitosan, which was obtained from shrimp shells, was used to synthesize polyurethane–chitosan foams (PUR+Ch) with different chitosan concentrations. Selected physico-chemical and sorption properties in relation to oil and water of these materials were determined. It was found that the amount of Ch added to the foam affected its morphology, hardness, density, and thermal and sorption properties. PUR foam with a 1.5% weight of Ch was characterized as having the highest water and oil sorption. The advantages of the tested material as an innovative product with potentially significant proecological values were estimated using strengths–weaknesses–opportunities–threats (SWOT) analysis. The conducted preliminary research made it possible to demonstrate the use of these materials in the processes of water treatment with the mentioned micropollutants.