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El tratamiento de la alergia a las proteínas de la leche de vaca se basa en la eliminación completa de las proteínas de leche de vaca de la dieta del niño y de la madre en los que reciben leche materna. Para lograr la remisión de los síntomas y la tolerancia futura, la exclusión debe ser total. En los niños que reciben fórmula, esta deberá tener hidrolizado extenso de proteínas en las formas leves o moderadas, mientras que aquellas a base de aminoácidos se reservan para los casos más graves. El tiempo de tratamiento, la adquisición de tolerancia y el momento para la prueba de provocación oral van a variar según el cuadro clínico, el mecanismo inmunológico implicado y la edad del paciente. El objetivo de este consenso ha sido reflejar el conocimiento actualizado junto con la experiencia de neonatólogos, pediatras, especialistas en alergia, nutrición y gastroenterología.

The treatment of cow's milk protein allergy is based on the complete elimination of cow's milk protein from the diet. To achieve remission of symptoms and future tolerance, exclusion must be total. In formula fed infants the extensively hydrolysed formula is the most appropriate option in mild or moderate forms, while those based on amino acids are reserved for the most severe cases. The treatment time, the acquisition of tolerance and the moment for the oral provocation test will vary according to the clinical picture, the immunological mechanism involved and the age of the patient. The aim of this consensus has been to reflect the updated knowledge together with the experience of neonatologists, pediatricians, experts in allergy, nutrition and gastroenterology

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Protein hydrolysates derived from aquaculture by-products hold significant promise as key components in the formulation of active films. In our study, we investigated the impact of different protein hydrolysates levels (0.4%, 0.8%, and 1.2%) obtained from the cutting by-product of Serra Spanish mackerel on the mechanical (PHSSM), morphological, optical, thermal, and antioxidant properties, as well as the degradability of biodegradable films. Four treatments were produced, varying the concentrations of PHSSM: C (control, without PHSSM), T4 (with 0.4% PHSSM), T8 (with 0.8% PHSSM), and T12 (with 1.2% PHSSM). These films were based on myofibrillar proteins from fish by-products and pectin extracted from yellow passion fruit. The incorporation of PHSSM led to enhanced barrier properties, resulting in a proportional reduction in water vapor permeability compared to the control film. However, high PHSSM levels (>0.8%) compromised film homogeneity and increased fracture susceptibility. Tensile strength remained unaffected (p > 0.05). PHSSM-enriched films exhibited reduced transparency and lightness, regardless of PHSSM concentration. The addition of PHSSM imparted a darker, reddish-yellow hue to the films, indicative of heightened visible light barrier properties. Moreover, increased PHSSM content (0.8% and 1.2%) appeared to accelerate film degradation in soil. Fourier transform infrared spectroscopy confirmed the presence of pectin-protein complexes in the films, with no discernible differences among the treated samples in the spectra. Incorporating PHSSM also enhanced film crystallinity and thermal resistance. Furthermore, an improvement in the antioxidant activity of the films was observed with PHSSM addition, dependent on concentration. The T8 emerged as the promising candidate for developing active primary packaging suitable for oxidation-sensitive foods.

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The treatment of cow's milk protein allergy is based on the complete elimination of cow's milk protein from the diet. To achieve remission of symptoms and future tolerance, exclusion must be total. In formula fed infants the extensively hydrolysed formula is the most appropriate option in mild or moderate forms, while those based on amino acids are reserved for the most severe cases. The treatment time, the acquisition of tolerance and the moment for the oral provocation test will vary according to the clinical picture, the immunological mechanism involved and the age of the patient. The aim of this consensus has been to reflect the updated knowledge together with the experience of neonatologists, pediatricians, experts in allergy, nutrition and gastroenterology.

El tratamiento de la alergia a las proteínas de la leche de vaca se basa en la eliminación completa de las proteínas de leche de vaca de la dieta del niño y de la madre en los que reciben leche materna. Para lograr la remisión de los síntomas y la tolerancia futura, la exclusión debe ser total. En los niños que reciben fórmula, esta deberá tener hidrolizado extenso de proteínas en las formas leves o moderadas, mientras que aquellas a base de aminoácidos se reservan para los casos más graves. El tiempo de tratamiento, la adquisición de tolerancia y el momento para la prueba de provocación oral van a variar según el cuadro clínico, el mecanismo inmunológico implicado y la edad del paciente. El objetivo de este consenso ha sido reflejar el conocimiento actualizado junto con la experiencia de neonatólogos, pediatras, especialistas en alergia, nutrición y gastroenterología.

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Chicken meat production has increased over the years, leading to a proportional increase in waste generation, which often contains high levels of proteins, such as viscera. Therefore, this study aimed to investigate the enzymatic hydrolysis of chicken viscera proteins as a strategy to value solid waste from the poultry industry. The hydrolysates were characterized for their antioxidant properties and molecular weight distribution. Additionally, the enzymatic hydrolysis process was scaled up from 125 mL flasks with 50 mL of protein solution to 3 L using a 6 L bioreactor. The enzymatic hydrolysis of chicken viscera proteins using a binary mixture of proteases (85.25 U/mL of each enzyme, Alcalase and Flavourzyme, totaling 170.5 U/mL) resulted in an increase of up to 245% in 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, 353% 2,2-diphenyl-1-picryl-hydrazyl (DPPH) in radical scavenging, 69% in Ferric Reducing Antioxidant Power Assay (FRAP) and 146% in total reducing capacity (TRC). The antioxidant properties of the protein hydrolysates are preserved during the scale-up of enzymatic hydrolysis. Protein fractions smaller than 5 kDa showed the highest ABTS and DPPH radical scavenging activities, while fractions greater than 30 kDa showed the best results for the FRAP method.

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Rice protein isolate (RPI) has been receiving increasing attention from the food industry due to its performance as an emulsifier. However, it is possible to enlarge its field of applications through enzymatic hydrolysis. Therefore, this work aimed to investigate the effects of the controlled enzymatic hydrolysis (degree of hydrolysis DH as 2, 6, and 10%) using Flavourzyme on the physicochemical properties of rice protein and to identify the minimum concentration of these hydrolysates (0.5, 1.0, and 1.5%) to form and stabilize oil/water emulsion. The physicochemical, interfacial tension (IT), and surface characteristics of RPI and their hydrolysates (RPH) were determined. Even at a lower protein concentration (1.0%), protein hydrolysate presented lower IT when compared with RPI at a higher protein concentration (1.5%). The interfacial tension decreased from 17.6 mN/m to 9.9 mN/m when RPI was hydrolyzed. Moreover, enzymatic hydrolysis (DH 6 and 10%) enhanced the protein solubility by almost 20% over a pH range of 3-11. The improved amphiphilic property of RPH, supported by the results of IT and solubility, was confirmed by the higher emulsion stability indicated by the Turbiscan and emulsion stability indexes. Emulsions stabilized by RPH (DH 6% and 10%) at lower protein concentrations (1%) exhibited better physical stability than RPI at higher protein concentrations (1.5%). In this work, we verified the minimum concentration of rice protein hydrolysate required to form and stabilize oil-in-water (O/W) emulsions.

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Cheese whey is the main by-product of dairy industries. It is used as a raw material for other value-added products, like whey protein concentrate. By using enzymes, this product can be further treated to obtain new higher value products, like whey protein hydrolysates. Proteases (EC: 3.4) represent a large segment of industrial enzymes, since they are used in several industries, including food. In this work, we describe three novel enzymes identified using a metagenomic approach. Metagenomic DNA from dairy industry stabilization ponds were sequenced, and the predicted genes were compared against the MEROPS database, focusing on families commercially used to produce whey protein hydrolysates. From a total of 849 candidates, 10 were selected for cloning and expression and three showed activities with both the chromogenic substrate, azocasein, and whey proteins. Particularly, Pr05, an enzyme from the yet uncultured phylum Patescibacteria, showed activity that is comparable to a commercial protease. All these novel enzymes could represent an alternative for dairy industries to produce value-added products from industrial by-products. KEY POINTS: • Over 19,000 proteases were predicted in a sequence-based metagenomic analysis. • Three proteases were successfully expressed and showed activity with whey proteins. • The enzyme Pr05 showed hydrolysis profiles of interest for food industry.

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Waste processing from fish and seafood manufacturers represents a sustainable option to prevent environmental contamination, and their byproducts offer different benefits. Transforming fish and seafood waste into valuable compounds that present nutritional and functional properties compared to mammal products becomes a new alternative in Food Industry. In this review, collagen, protein hydrolysates, and chitin from fish and seafood byproducts were selected to explain their chemical characteristics, production methodologies, and possible future perspectives. These three byproducts are gaining a significant commercial market, impacting the food, cosmetic, pharmaceutical, agriculture, plastic, and biomedical industries. For this reason, the extraction methodologies, advantages, and disadvantages are discussed in this review.

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Skin aging represents a health and aesthetic problem that could result in infections and skin diseases. Bioactive peptides can potentially be used in skin aging regulation. Chickpea (Cicer arietinum L.) selenoproteins were obtained from germination with 2 mg Na2SeO3/100 g of seeds for 2 days. Alcalase, pepsin, and trypsin were used as hydrolyzers, and a membrane < 10 kDa was used to fractionate the hydrolysate. Se content, antioxidant capacity, elastase and collagen inhibition, functional stability, and preventative capacity were analyzed. Significant increases in Se content were found in germinated chickpea flour and protein related to the control. An increase of 38% in protein was observed in the selenized flour related to the control. A band (600-550 cm-1) observed in the selenized hydrolysates suggested the insertion of Se into the protein. Hydrolysates from pepsin and trypsin had the highest antioxidant potential. Se enhanced the stability of total protein and protein hydrolysates through time and increased their antioxidant capacity. Hydrolysates > 10 kDa had higher elastase and collagenase inhibition than the total protein and hydrolysates < 10 kDa. Protein hydrolysates < 10 kDa 6 h before UVA radiation had the highest inhibition of collagen degradation. Selenized protein hydrolysates showed promising antioxidant effects that could be related to skin anti-aging effects.

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At least half the population in industrialized countries suffers from obesity due to excessive accumulation of adipose tissue. Recently, rice (Oryza sativa) proteins have been considered valuable sources of bioactive peptides with antiadipogenic potential. In this study, the digestibility and bioaccessibility in vitro of a novel protein concentrate (NPC) from rice were determined through INFOGEST protocols. Furthermore, the presence of prolamin and glutelin was evaluated via SDS-PAGE, and their potential digestibility and the bioactivity of ligands against peroxisome proliferator-activated receptor gamma (PPARγ) were explored by BIOPEP UWM and HPEPDOCK. For the top candidates, molecular simulations were conducted using Autodock Vina to evaluate their binding affinity against the antiadipogenic region of PPARγ and their pharmacokinetics and drug-likeness using SwissADME. Simulating gastrointestinal digestion showed a recovery of 43.07% and 35.92% bioaccessibility. The protein banding patterns showed the presence of prolamin (57 kDa) and glutelin (12 kDa) as the predominant proteins in the NPC. The in silico hydrolysis predicts the presence of three and two peptide ligands in glutelin and prolamin fraction, respectively, with high affinity for PPARγ (≤160). Finally, the docking studies suggest that the prolamin-derived peptides QSPVF and QPY (-6.38 & -5.61 kcal/mol, respectively) have expected affinity and pharmacokinetic properties to act as potential PPARγ antagonists. Hence, according to our results, bioactive peptides resulting from NPC rice consumption might have an antiadipogenic effect via PPARγ interactions, but further experimentation and validation in suitable biological model systems are necessary to gain more insight and to provide evidence to support our in silico findings.

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Protein hydrolysates are a promising source of bioactive peptides. One strategy by which they can be obtained is fermentation. This method uses the proteolytic system of microorganisms to hydrolyze the parental protein. Fermentation is a little-explored method for obtaining protein hydrolysates from amaranth. Different strains of lactic acid bacteria (LAB) and Bacillus species isolated from goat milk, broccoli, aguamiel, and amaranth flour were used in this work. First, the total protein degradation (%TPD) of amaranth demonstrated by the strains was determined. The results ranged from 0 to 95.95%, the strains that produced a higher %TPD were selected. These strains were identified by molecular biology and were found to correspond to the genera Enterococcus, Lactobacillus, Bacillus, and Leuconostoc. Fermentation was carried out with amaranth flour and the selected strains. After this process, water/salt extracts (WSE) containing the released protein hydrolysates were obtained from amaranth doughs. The peptide concentration was measured by the OPA method. The antioxidant, antihypertensive and antimicrobial activity of the WSE was evaluated. In the FRAP test, the best WSE was LR9 with a concentration of 1.99 µMTE/L ± 0.07. In ABTS, 18C6 obtained the highest concentration with 19.18 µMTE/L ± 0.96. In the DPPH test, there was no significant difference. In terms of antihypertensive activity, inhibition percentages ranging from 0 to 80.65% were obtained. Some WSE were found to have antimicrobial properties against Salmonella enterica and Listeria monocytogenes. Fermentation of amaranth with LAB and Bacillus spp. allowed the release of protein hydrolysates with antioxidant, antihypertensive, and antimicrobial activity.

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Fish protein hydrolysates (FPHs) can be obtained from substrates such as fish muscle, skin, and wastes and assign value to these fish by-products. Proteolytic enzymes catalyze the hydrolysis of these fish substrates' peptide bonds resulting in smaller peptides that present several bioactive properties. Hydrolysates' bioactive properties are a function of the fish species used as the substrate, the enzyme selectivity or specificity, pH and temperature applied in the reaction, etc. Furthermore, many pre-treatment methods are being applied to fish protein substrates to improve their enzyme susceptibility and increase the number of smaller bioactive peptides. This review addresses the production of FPHs and the main bioactive properties evaluated recently in the literature and emphasizes the substrate treatments by high-pressure processing, microwave, ultrasound, and thermal treatments to achieve better bioactivity making essential amino acids more available in peptides. The bioactive properties most found in FPHs were antioxidants, antimicrobials, anticancer, and antihypertensive. These bioactivities may vary depending on the conditions of hydrolysis, fish species, and fractionation and isolation of specific peptides.New technologies for the treatment of by-products can reduce process losses and achieve better results by cleavage of proteins. Conversely, encapsulation and film utilization can improve bioactivity, bioavailability, and controlled release when applied to foods, resulting in improved health.

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Increased soil salinity is one of the main concerns in agriculture and food production, and it negatively affects plant growth and crop productivity. In order to mitigate the adverse effects of salinity stress, plant biostimulants (PBs) have been indicated as a promising approach. Indeed, these products have a beneficial effect on plants by acting on primary and secondary metabolism and by inducing the accumulation of protective molecules against oxidative stress. In this context, the present work is aimed at comparatively investigating the effects of microbial (i.e., Azospirillum brasilense) and plant-derived biostimulants in alleviating salt stress in tomato plants by adopting a multidisciplinary approach. To do so, the morphological and biochemical effects were assessed by analyzing the biomass accumulation and root characteristics, the activity of antioxidant enzymes and osmotic stress protection. Furthermore, modifications in the metabolomic profiles of both leaves and root exudates were also investigated by ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS). According to the results, biomass accumulation decreased under high salinity. However, the treatment with A. brasilense considerably improved root architecture and increased root biomass by 156% and 118% in non-saline and saline conditions, respectively. The antioxidant enzymes and proline production were enhanced in salinity stress at different levels according to the biostimulant applied. Moreover, the metabolomic analyses pointed out a wide set of processes being affected by salinity and biostimulant interactions. Crucial compounds belonging to secondary metabolism (phenylpropanoids, alkaloids and other N-containing metabolites, and membrane lipids) and phytohormones (brassinosteroids, cytokinins and methylsalicylate) showed the most pronounced modulation. Overall, our results suggest a better performance of A. brasilense in alleviating high salinity than the vegetal-derived protein hydrolysates herein evaluated.

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The work aimed to develop a gel as a protective barrier of common bean protein hydrolysates to be incorporated into a Greek-style yogurt and evaluate the sensory perception and biological potential. The gel was formed by complex coacervation and induced heat at a pH 3.5 and 3:1 biopolymer ratio (whey protein and gum arabic). The gel presented a 39.33% yield, low syneresis (0.37%), and a gel strength of 100 gf. The rheological properties showed an elastic behavior (G' > G″). The gel with the most stable characteristics favored the incorporation of 2.3 g of hydrolysates to be added into the Greek-style yogurt. Nutritionally, the Greek-style yogurt with the encapsulated hydrolysates presented 9.96% protein, 2.27% fat, and 1.76% carbohydrate. Syneresis (4.64%), titratable acidity (1.39%), and viscoelastic behavior presented similar characteristics to the Greek-style control yogurt. The bitterness and astringency in yogurt with encapsulated hydrolysates decreased 44% and 52%, respectively, compared to the yogurt control with the unencapsulated hydrolysates. The Greek-style yogurt with the encapsulated hydrolysates showed the ability to inhibit enzymes related to carbohydrate metabolism (α-amylase (92.47%) and dipeptidyl peptidase-4 (75.24%) after simulated gastrointestinal digestion). The use of gels could be an alternative to transporting, delivering, and masking off-flavors of common bean protein hydrolysates in food matrices to decrease glucose absorption for type 2 diabetes patients.

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This study investigated the use of Novo Pro-D® (NPD) and Ficin (FC) as alternative proteases for the production of bioactive peptides with reduced allergenicity from whey protein concentrate (WPC). In addition, the use of high hydrostatic pressure processing as pre-treatment of WPC and its impact on the final characteristics of hydrolysates were also evaluated. NPD treatments generated hydrolysates with a 98% reduction of soluble proteins, greater in vitro antioxidant capacity, and less immunoreactivity when compared to FC ones. However, pre-treatment was an essential tool to improve WPC hydrolysis when FC was used, resulting in hydrolysates with less soluble proteins, enhanced antioxidant capacity, and less allergenicity compared with conventional hydrolysis. As for NPD, the pre-treatment of WPC improved the in vitro antioxidant capacity and resulted in a 100% reduction in immunoreactivity to ß-lactoglobulin in a shorter processing time. Importantly, bioactive peptides generated by FC displayed an improved ability to induce in vitro arterial relaxation, compared with those obtained from NPD process. Therefore, this study provides innovative evidence regarding how the proteases used for production of whey hydrolysates can improve its biological effects, and discloses the use of high hydrostatic pressure combined with enzymatic hydrolysis as a promising alternative to produce hydrolysates with improved properties.

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Protein hydrolysates from fishery byproducts have resulted to be nutraceutical ingredients with potential to be applied in human nutrition; however, critical quality attributes are dependent on some process parameters such as enzyme source and degree of hydrolysis. This study analyzed the biochemical properties and in vitro antioxidant activity (using DPPH, ABTS, and FRAP assays), of protein hydrolysates at 10, 20, and 30% degree of hydrolysis (DH), measured by pH-STAT and prepared from sea catfish (Bagre panamensis) muscle and casein as protein sources by treatment with alcalase (ALC) and a semi-purified protease extract (SPE) from B. panamensis intestinal tissues as enzyme sources. With SPE, the DH was reached faster than ALC regardless of the protein substrate used. Sea catfish muscle (MUSC) hydrolysate made with SPE at 30% DH showed the highest antioxidant activity (DPPH: 118.8 µmoles TE/mg; ABTS: EC50 of 1.5 mg/mL). In FRAP assay, the MUSC hydrolysates produced with SPE or ALC at 20% DH showed the higher activity (0.38 and 0.40 µmoles TE/mg, respectively). MUSC hydrolysates made with SPE contained the highest proportion of peptides with MW < 1.35 kDa and had a high protein content (72 to 78%), and almost 50% of the amino acids were essential. These results suggest that intestinal proteases and muscle of marine catfish represent a potential source to elaborate antioxidant protein hydrolysates. Our results promote the full utilization of this fish species and offer a biotechnological strategy for the management and valorization of its byproducts.

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BACKGROUND: In modern society, there is a tendency to consume products with natural origins and minimum chemical additives. This has encouraged the replacement of synthetic antioxidants for the ones obtained from natural sources, such as the antioxidants acquired from enzymatic protein hydrolysates. OBJECTIVE: In this study, the process of enzymatic hydrolysis of proteins from bovine plasma, which produces hydrolysates with an Antioxidant Capacity (AC), was scaled up from 1 to 5 L. METHODS: An experimental design was developed in 1 L to evaluate the effect of the Substrate concentration (So) on the time needed to reach a Degree of Hydrolysis (DH) of 20% as well as the AC. RESULTS: The best conditions in the 1 L reactor controlled by a Titrando 842 were transferred to 5L in a BioFlo310 reactor. These conditions were achieved at a ratio of 80g/L of the substrate and 0.89 AU of Alcalase 2.4L/g of the substrate in order to obtain a level of 16.36 ± 0.21min of the 20% of DH and antioxidant capacity of 58.98 ± 1.80%. CONCLUSION: The results showed that DH depends significantly on So, while the antioxidant capacity only depends on the DH. Additionally, the dimensional analysis using Re as a scaling criterion allowed us to obtain the same results in the model (1 L) and the prototype (5 L).

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The aim of this study was to obtain flavor molecules from goat by-product hydrolysates, emphasizing the thermal action during processing. A mixture of by-products submitted or not to the inactivation of endogenous enzymes was used, followed by hydrolysis with the proteolytic enzyme Alcalase® (Bacillus licheniformis), and autoclaving after hydrolysis. The production of hydrolysates provided both quantitative and qualitative data on the precursors involved in the aromatic formation of protein hydrolysates. The inactivation process of endogenous enzymes resulted in hydrolysates with a higher degree of hydrolysis and greater protein content. The autoclaving process produced a significant increase in the concentration of free amino acids and maltose and a reduction in the glucose content. Application of the two heat treatments resulted in the production of goat by-product protein hydrolysates with different volatile profiles. The goat by-product protein hydrolysate without heat treatment but with autoclaving (HCA), showing a higher concentration of flavor precursors and the formation of heterocyclic volatiles, is expected to impact the aroma quality of goat hydrolysates.

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The objective was to investigate the anti-adipogenesis potential of selected legume protein hydrolysates (LPH) and combinations using biochemical assays and in silico predictions. Black bean, green pea, chickpea, lentil and fava bean protein isolates were hydrolyzed using alcalase (A) or pepsin/pancreatin (PP). The degree of hydrolysis ranged from 15.5% to 35.5% for A-LPH and PP-LPH, respectively. Antioxidant capacities ranged for ABTS•+ IC50 from 0.3 to 0.9 Trolox equivalents (TE) mg/mL, DPPH• IC50 from 0.7 to 13.5 TE mg/mL and nitric oxide (NO) inhibition IC50 from 0.3 to 1.3 mg/mL. LPH from PP-green pea, A-green pea and A-black bean inhibited pancreatic lipase (PL) (IC50 = 0.9 mg/mL, 2.2 mg/mL and 1.2 mg/mL, respectively) (p < 0.05). For HMG-CoA reductase (HMGR) inhibition, the LPH from A-chickpea (0.15 mg/mL), PP-lentil (1.2 mg/mL), A-green pea (1.4 mg/mL) and PP-green pea (1.5 mg/mL) were potent inhibitors. Combinations of PP-green pea + A-black bean (IC50 = 0.4 mg/mL), A-green pea + PP-green pea (IC50 = 0.9 mg/mL) and A-black bean + A-green pea (IC50 = 0.6 mg/mL) presented synergistic effects to inhibit PL. A-chickpea + PP-lentil (IC50 = 0.8 mg/mL) and PP-lentil + A-green pea (IC50 = 1.3 mg/mL) interacted additively to inhibit HMGR and synergistically in the combination of A-chickpea + PP-black bean (IC50 = 1.3 mg/mL) to block HMGR. Peptides FEDGLV and PYGVPVGVR inhibited PL and HMGR in silico, showing predicted binding energy interactions of -7.6 and -8.8 kcal/mol, respectively. Combinations of LPH from different legume protein sources could increase synergistically their anti-adipogenic potential.

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The waste of fish resources constitutes a serious environmental problem that must be avoided. The valorisation of by-catch species and decreasing the discard rate constitute a more efficient and sustainable use of these marine biomasses. In this work, we characterize and propose different potential uses for Stromateus brasiliensis, another frequently discarded (≥ 90%) and poorly studied by-catch species captured in the South Atlantic Ocean (FAO 41) by trawler fishing fleets. Furthermore, in the case of this species, freezing and frozen storage of the whole fish is the only strategy currently employed for its exploitation. The results revealed that muscle from S. brasiliensis presented a high content of polyunsaturated fatty acids (20.34%) and that the concentrations of both total diacyl glyceryl ethers (2.41%) and heavy metals (Hg 0.038, Pb 0.006 and Cd 0.018 mg/kg) were below the established limits for safe human consumption. Likewise, the protein hydrolysates proved to be a good source of amino acids for human consumption or animal feeding. Minced muscle blocks could be made by a mechanical separation process of the flesh, and the composition of minced muscle did not differ much from that of the whole fish. Furthermore, this process allows the incorporation of cryoprotectants and antioxidants to extend the frozen shelf life of this fatty fish. An extraction process from mechanically mixed skin and bones yielded a good source of collagen that should not be neglected.

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El género Pseudomonas es una fuente importante de proteasas; sin embargo, su uso está restringido en la industria alimentaria. El clonaje permite aprovechar la capacidad catalítica de estas enzimas mediante su producción en microorganismos inocuos. Por otro lado, las leguminosas son fuentes ricas en proteínas, a partir de las cuales se pueden obtener compuestos con valor agregado mediante procesos de hidrólisis enzimática. En este estudio, se produjo y caracterizó una proteasa recombinante (PT4) alcalina y termoestable de Pseudomonas aeruginosa M211, para la obtención de hidrolizados proteicos de leguminosas. Para ello, el gen de la proteasa se clonó en el vector pJET1.2/blunt utilizando E. coli DHalfa como hospedero. El análisis de la secuencia nucleotídica parcial de la proteasa indicó un 99 % de similitud con Peptidasas de la Familia M4 de Pseudomonas aeruginosa. La enzima recombinante presentó un peso molecular de 80 kDa, demostró ser activa y estable en condiciones alcalinas y termófilas con un pH y temperatura óptimos de 8 y 60 °C, respectivamente, y fue inhibida por EDTA. Además, hidrolizó proteínas de semillas de Glycine max, Phaseolus lunatus, Lupinus mutabilis y Erythrina edulis, obteniéndose fracciones peptídicas menores a 40 kDa. Esta proteasa recombinante se podría utilizar en la elaboración de hidrolizados proteicos funcionales a partir proteínas de distintas fuentes y residuos agroalimentarios.

The genus Pseudomonas is an important source of proteases; however, in the food industry the use of this bacterium is restricted. Cloning allows for the use of the proteolytic activity of Pseudomonas proteases through their production in innocuous microorganisms. Leguminous are protein-rich sources from which value-added compounds can be obtained through enzymatic hydrolysis. In this study, an alkaline and thermostable recombinant protease (PT4) from Pseudomonas aeruginosa M211 was cloned and characterized in order to obtain protein hydrolysates from leguminous. Therefore, protease gene was cloned into the pJET1.2 / blunt vector using E. coli DHalpha as a host. Analysis of protease partial nucleotide sequence showed 99% homology with Peptidases M4 Family from Pseudomonas aeruginosa. The molecular weight of the recombinant enzyme was 80 kDa, it was active and stable under alkaline and thermophilic conditions, presented an optimum pH and temperature of 8 and 60 °C, respectively, and was inhibited by EDTA. In addition, it hydrolysed Glycine max, Phaseolus lunatus, Lupinus mutabilis y Erythrina edulis proteins, obtaining peptide fractions less than 40 kDa. This recombinant protease could be used in the elaboration of functional hydrolysates using protein from different sources and agricultural waste.

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