Preparation Of Protein Hydrolysates Research Articles

Characteristics and Bioactivities of Protein Hydrolysate from Cricket (Acheta domesticus) Powder Defatted Using Ethanol with Aid of Vacuum Impregnation.

Cricket is a potential proteinaceous source used for protein hydrolysate (PH) preparation, having several biological activities. Nevertheless, cricket has high lipid contents, which are susceptible to oxidation during PH preparation. Thus, ethanol was used together with vacuum impregnation (VI) to enhance defatting efficacy before PH preparation. Also, bioavailability of the digest of PH after gastrointestinal tract (GIT) digestion via the Caco-2 monolayer was assessed. Cricket powder was defatted using ethanol for 1-4 h. Lipid contents were decreased with enhancing time until 2 h. Additionally, the defatting efficacy was augmented when ethanol combined with VI at 4 cycles for 2 h (VI-E-2) was implemented. Lowered mono- and polyunsaturated fatty acid contents were also observed in the VI-E-2 sample. The VI-E-2 sample was used to prepare PH using Alcalase and Flavourzyme (0.2-0.4 units/g dry sample). PH prepared by Alcalase hydrolysis at 0.2 units/g dry sample (A-0.2) showed the higher ABTS radical-scavenging activity and FRAP, compared to that prepared by Flavourzyme hydrolysis (p < 0.05). Thus, the A-0.2 sample was selected for digestion via the GIT system. The obtained digest (500-1000 μg/mL) had bioavailability of peptides, depending on the levels used. Therefore, PH from defatted cricket powder could be a promising ingredient for food applications.

Characterization of the extracellular proteases from Bacillus inaquosorum strain E1-8 and its application in the preparation of hydrolysates from plant and animal proteins with antioxidant, antifreeze and anti-browning properties.

Bacillus inaquosorum strains is widely recognized for their plant-growth-promoting and biocontrol capabilities, yet their roles in protease production remain unclear. The present study aimed to comprehensively assess the protease-producing performance of B. inaquosorum strain E1-8, at the same time as exploring the novel application of agricultural Bacillus proteases in the preparation of protein hydrolysates for fresh-cut fruits preservation. First, genomic sequencing revealed the diversity of E1-8 proteases, indicating 15 putative extracellular proteases. Subsequently, the fermentation conditions for E1-8 protease production were optimized, with sweet potato powder and soybean meal identified as the most suitable carbon and nitrogen sources, respectively, resulting in a maximum protease activity of 321.48 U mL-1. Upon culturing the strain under these optimized conditions, only an S8 family serine protease and an M48 family metalloprotease were revealed by secretomic analysis and protease inhibitor assays. Additionally, the optimal protease conditions for generating protein hydrolysates from soy, pea, fish and porcine proteins were determined. The molecular weight of the hydrolysates primarily ranged from 2000 to 180 Da, with a total of 17 amino acids identified. The application of these hydrolysates demonstrated a 2,2-diphenyl-1-picrylhydrazyl (i.e. DPPH) scavenging activity ranging from 58.64% to 84.12%, significantly reducing of the melting peaks and the freezing points. Furthermore, the browning index of apple slices stored at 4 °C decreased by 14.81% to 22.15% on the second day, and similar effects were observed in fresh-cut banana stored at 4 °C for 7 days. The protein hydrolysates obtained exhibit remarkable antioxidant, antifreeze and anti-browning properties for fresh-cut fruits. © 2024 Society of Chemical Industry.

Purification of Trypsin from Sardine (Sardina pilchardus) Viscera and Its Application in Preparation of Antioxidative Fish Protein Hydrolysates

Purification of Trypsin from Sardine (Sardina pilchardus) Viscera and Its Application in Preparation of Antioxidative Fish Protein Hydrolysates

Tea (Camellia sinensis (L.) Kuntze) as an emerging source of protein and bioactive peptides: A narrative review.

Tea residues represent one of the major agricultural wastes that are generated after the processing of tea. They account for 21-28% of crude protein and are often discarded without the extraction of valuable proteins. Due to various bioactivity and functional properties, tea proteins are an excellent alternative to other plant-based proteins for usage as food supplements at a higher dosage. Moreover, their good gelation capacity is ideal for the manufacturing of dairy products, jellies, condensation protein, gelatin gel, bread, etc. The current study is the first to comprehend various tea protein extraction methods and their amino acid profile. The preparation of tea protein bioactive peptides and hydrolysates are summarized. Several functional properties (solubility, foaming capacity, emulsification, water/oil absorption capacity) and bioactivities (antioxidant, antihypertensive, antidiabetic) of tea proteins are emphasized.

Functional Properties and Proximate Analysis of Fish Waste Protein Hydrolysate Processed Using Enzymes

A huge production of fish and their processing waste give rise to by-products comprises up to 70% depending on the species, size and processing method. The waste includes visceral parts, head, frames, bones, skin and cut-offs are rich source of protein with high functional properties. It is generally discarded which is a wastage of nutrient source and leading to environmental issues. Therefore, it was aimed to utilized the by-products for maximum recovery of nutrients by enzyme hydrolysis method for the preparation of protein hydrolysate with the used of papain and pepsin for digestion following different hydrolysis conditions. With the hydrolysis of papain enzyme (1 to 6%), the protein content of finfish waste protein hydrolysate ranges from 19.17% ± 0.06 to 73.14% ± 0.08 and that of shellfish waste protein hydrolysate prepared with 5,10 and 15% papain enzyme showed 26.73% ± 0.04 to 40.4% ± 0.5 which is comparatively low. Whereas the highest protein content was observed in 1% pepsin enzyme treated finfish waste protein hydrolysate with 80.55% ± 0.07. Besides, the hydrolysates were composed of 6.91% ± 0.05 to 10.46% ± 0.05 (moisture content), 0.6% ± 0.01 to 2.4% ± 0.01 (ash content) and 0.02% ± 0.005 to 0.09% ± 0.005 (fat content). The hydrolysates were highly soluble ranges from 72.73% ± 0.05 to 93.83% ± 0.1 which indicates development of small size hydrophilic with highly solvated polypeptide particles. A reduced phenomena of foaming capacity and stability were observed in shellfish waste protein hydrolysate in contrast with finfish waste protein hydrolysate. Similar pattern was also resulted in emulsifying stability index. Whereas the emulsifying activity index was in the range of 6.15 ± 0.03 to 9.85 ± 0.07 m2/g. The water holding capacity of finfish and shellfish waste protein hydrolysate ranges from 3.4 to 4.23 gm/gm hydrolysate and 1.53 to 1.63 gm/gm hydrolysate respectively which is resulted by the difference in molecular weight of the peptide. The hydrolysates extracted from different sample with different enzyme and concentration at varying conditions were more or less similar ranges from 3.7 to 4.1 gm/gm protein hydrolysate (oil holding capacity). Hence, high protein content with good functional properties of the protein hydrolysate prepared with the utilization of fish waste is a positive impact on the attempt made to recover nutrient by enzymatic hydrolysis.

Enzymatic Preparation of Mushroom By-product Protein Hydrolysates (Mb-PPHs)

The excessive use of chemical fertilizers can cause severe environmental damage. In recent decades, the application of biostimulants to improve soil composition and stimulate plant growth has contributed significantly to environmental preservation. In this paper, we studied the production and characterization of an amino acid/peptide-enriched biostimulant using edible mushroom (Agaricus bisporus) by-products (tails and nonmarketable mushrooms) as raw materials and commercial proteases as hydrolytic agents. A single hydrolytic process using four different endoproteases, Alcalase®, L-450, Flavourzyme® or papain, and a sequential hydrolytic process using two proteases, an endoprotease and an exoprotease, Alcalase® + Flavourzyme® or L-450 + Flavourzyme), were conducted. A preevaluation of potential plant biostimulants was also carried out, testing the biostimulant capacity of single and sequential Mb-PPHs to stimulate maize seed germination and root growth, as well as the evaluation of the vigor index (VI), with very promising results.Graphical

Preparation of sunflower seed-derived umami protein hydrolysates and their synergistic effect with monosodium glutamate and disodium inosine-5'-monophosphate.

Sunflower seeds are rich in protein and can be an excellent raw material for the production of umami peptides. In this study, sunflower seed meal, which was defatted at a low temperature, was taken as the raw material, and proteins were separated, followed by hydrolyzation for 4h by flavourzyme® to obtain hydrolysates with strong umami intensity. These hydrolysates were deamidated using glutaminase to increase the umami intensity. The highest umami value of 11.48 was recorded for hydrolysates deamidated for 6h, and the umami intensity was determined. The umami hydrolysates mixed with 8.92mmol IMP + 8.02mmol MSG showed the highest umami value of 25.21. Different concentrations of ethanol were used for further separation of hydrolysates, and the highest umami value of 13.54 was observed for 20% ethanol fraction. The results of this study provide utilization method for sunflower seed meal protein and a theoretical basis for the preparation of umami peptides. PRACTICAL APPLICATION: A large number of sunflower seed meals after oil production are used as feed for livestock and poultry. Sunflower seed meal is rich in protein, and umami amino acid composition in sunflower seed meal is up to 25%-30%, which is potentially an excellent raw material for the production of umami peptides. The umami flavor and synergistic effect of obtained hydrolysates, with MSG and IMP, were analyzed in the present study. We intend to provide a novel way for utilization of protein from sunflower seed meal along with a theoretical basis for the preparation of umami peptides.

Preparation of Hypoallergenic Whey Protein Hydrolysate by a Mixture of Alcalase and Prozyme and Evaluation of Its Digestibility and Immunoregulatory Properties.

Whey protein (WP) has nutritional value, but the presence of β-lactoglobulin (β-LG) and α-lactalbumin (α-LA) cause allergic reactions. In this study, hypoallergenic whey protein hydrolyate (HWPH) was prepared by decomposing β-LG and α-LA of WP using exo- and endo-type proteases. The enzyme mixing ratio and reaction conditions were optimized using response surface methodology (RSM). Degradation of α-LA and β-LG was confirmed through gel electrophoresis, and digestion, and absorption rate, and immunostimulatory response were measured using in vitro and in vivo systems. Through RSM analysis, the optimal hydrolysis conditions for degradation of α-LA and β-LG included a 1:1 mixture of Alcalase and Prozyme reacted for 10 h at a 1.0% enzyme concentration relative to substrate. The molecular weight of HWPH was <5 kDa, and leucine was the prominent free amino acid. Both in vitro and in vivo tests showed that digestibility and intestinal permeability were higher in HWPH than in WP. In BALB/c mice, as compared to WP, HWPH reduced allergic reactions by inducing elevated Type 1/Type 2 helper T cell ratio in the blood, splenocytes, and small intestine. Thus, HWPH may be utilized in a variety of low allergenicity products intended for infants, adults, and the elderly.

Simultaneous Preparation of Chitin and Flavor Protein Hydrolysates from the By-Products of Shrimp Processing by One-Step Fermentation with Lactobacillus fermuntum.

One-step fermentation, inoculated with Lactobacillus fermentum (L. fermentum) in shrimp by-products, was carried out to obtain chitin and flavor protein hydrolysates at the same time. The fermentation conditions were optimized using response surface methodology, resulting in chitin with a demineralization rate of 89.48%, a deproteinization rate of 85.11%, and a chitin yield of 16.3%. The surface of chitin after fermentation was shown to be not dense, and there were a lot of pores. According to Fourier transform infrared spectroscopy and X-ray diffraction patterns, the fermented chitin belonged to α-chitin. More than 60 volatiles were identified from the fermentation broth after chitin extraction using gas chromatography-ion transfer spectrometry analysis. L. fermentum fermentation decreased the intensities of volatile compounds related to unsaturated fatty acid oxidation or amino acid deamination. By contrast, much more pleasant flavors related to fruity and roasted aroma were all enhanced in the fermentation broth. Our results suggest an efficient one-step fermentation technique to recover chitin and to increase aroma and flavor constituents from shrimp by-products.

Moringa oleifera Lam. seed proteins: Extraction, preparation of protein hydrolysates, bioactivities, functional food properties, and industrial application

Moringa oleifera Lam. (Moringaceae) consumed in several tropical and subtropical countries is a highly valued multi-purpose herbal plant with numerous medicinal properties and high nutritional value. Moringa seeds contain high protein content (∼52%) with all the essential amino acids and could act as a potential source of functional protein isolate for application in food and biomedical industries. The objective of the current review is to highlight the recent developments in the various protein extraction methods and preparation of protein hydrolysates from moringa seeds. The recent findings on the bioactivities, functional properties, and industrial applications of moringa seed proteins are noteworthy. Therefore, the study was framed to discuss relevant research reports in six sections viz-moringa seed protein extraction, moringa seed protein isolates/hydrolysates, amino acid profile, functional properties, bioactivities, and food or biomedical industrial applications. Moringa seed proteins exhibited antimicrobial, antioxidant, antiviral, antidiabetic, hepatoprotective, anticancer, and cardio-protective activity. Moringa seed protein isolates revealed good foaming capacity and stability, emulsification capacity, water, and oil absorption capacity. Industrially moringa seed protein isolates could be potentially used as milk coagulant, thickening agent, food and feed ingredient, and drug delivery agent. Besides, moringa seed protein isolate is reported to heal diabetes, control inflammation and hypertension. • First review on functional attributes and bioactivities of the moringa seed proteins. • Extraction of moringa seed protein and preparation of its hydrolysate are discussed. • Moringa seed protein possess anti-diabetic, organ-protective and antiviral activities. • Characterization and application of moringa seed protein are highlighted in the review.

Progress of Preparation and Physiological Activity of Fish Visceral Protein Hydrolysates

Progress of Preparation and Physiological Activity of Fish Visceral Protein Hydrolysates

Systematic investigation of the amino acid profiles that are correlated with xanthine oxidase inhibitory activity: Effects, mechanism and applications in protein source screening

This study aimed to investigate the dipeptide amino acid profiles correlated with xanthine oxidase (XOD) inhibitory activity and guide screening to determine suitable sources for XOD inhibitor protein hydrolysate preparation. The XOD inhibitory activities of 400 dipeptides were predicted via molecular docking and measured in vitro, and amino acids containing aromatic structures and charged residues were correlated with high XOD inhibitory properties. Subsequently, the effects of Cys-Glu and Lys-Glu, which showed the highest in vitro activities, were examined in hyperuricaemic mice, and were found to alleviate hyperuricaemia and modulate the gut microbiota. Furthermore, a suitable protein from Oreochromis mossambicus with high contents of charged (8.6%) and aromatic (1.67%) amino acids was screened, and the in vitro inhibitory rates of protein hydrolysate prepared from O. mossambicus against XOD were found to be 21.90% and 44.51% at 40 and 100 mg/ml, respectively. This study provides a strategy for screening protein hydrolysate sources with certain activities based on amino acid profiles.

Bioactivity and Functional Properties of Protein Hydrolysate from Muscle and Visceral Waste of Ribbon Fish (Lepturacanthus savala) Extracted by Three Different Proteolytic Enzymes

The study focuses on utilization of solid visceral waste from ribbon fish in preparation of protein hydrolysates, possessing bioactive properties. Three different proteolytic enzymes (alcalase 2.4 U/g, flavourzyme 500 U/g, and papain 1 U/mL) were used to standardize the preparation of visceral waste protein hydrolysates (VPH) in comparison to muscle protein hydrolysate (MPH). Based on the preliminary studies, the hydrolysis process was standardized to 4 h at 1.5 % (w/v) enzyme concentration. MPH and VPH form all the enzymes were taken to study the bioactive (ACE-1 and antioxidant activity) and functional properties. MPH and VPH extracted from alcalase (IC50 = 0.835 and 0.902 mg/mL) showed higher angiotensin converting enzyme-1 (ACE-1) inhibitory activity than flavourzyme (IC50 = 1.602 and 1.323 mg/mL) and papain (1.263 and 1.565 mg/mL). Similarly, alcalase extracted samples were showed higher levels of radical scavenging activity (IC50 = 2.538 and 2.835 mg/mL) than papain (IC50 = 8.382 and 9.389 mg/mL) and flavourzyme (IC50 = 10.562 and 11.56 mg/mL). The present study proves that visceral waste, which is often discarded in a larger quantity, polluting the environment can be converted into a nutraceutical component with greater health benefits.

Preparation and Characterization of Microcapsules Containing Antioxidant Fish Protein Hydrolysates: a New Use of Bycatch in Brazil.

In this study, we evaluated the effect of complexation and microencapsulation with pea protein on the antioxidant activity of protein hydrolysates from bycatch in Brazil. The zeta potential values of complexes changed from negative to positive with the increase of pea protein as a result of positively charged complexes formation. The increase in the ratio of pea protein/hydrolysates also resulted in increased turbidity in all samples. Particle size measurements indicated that the complexes tended to form larger aggregates (ranged from 61.5 ± 1.7μm to 183 ± 2.8μm). The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of the pea protein/fish protein hydrolysate complexes was higher than that of the protein hydrolysates alone. Moreover, increasing levels of pea protein did not affect the antioxidant activity of fish protein hydrolysates. The complexes of the Paralonchurus brasiliensis were chosen for the microencapsulation process by spray-drying. The results revealed that spray-drying did not have a significant effect (P > 0.05) on the protein hydrolysate antioxidant activity when they were complexed with pea protein. Thus, this work suggests that the complexation with pea protein and subsequent microencapsulation by spray-drying is an efficient way to protect the biological activity of protein hydrolysates obtained from bycatch. This study provides evidence for the potential use of bycatch from shrimp fisheries as functional ingredients or nutraceuticals.

Peptidases from Maclura Pomifera for Preparation of Food Protein Hydrolysates: Purification by Single-Step Chromatography and Characterization of Pomiferin I.

Our objective was to isolate peptidases from the latex of Maclura pomifera fruits and use them to hydrolyze food proteins, as well as to purify and characterize the main peptidase. Two partially purified proteolytic extracts were prepared by ethanol (EE) and acetone (AE) precipitation from an aqueous suspension of exuded fruit latex. EE was used to hydrolyze food proteins with a ratio of 0.19 caseinolytic units (Ucas) per mg of substrate. Different values of hydrolysis degree were observed for hydrolysates of egg white, soy protein isolate, and casein at 180min (9.3%, 31.1%, and 29.1%, respectively). AE was employed to purify a peptidase which exhibited an isoelectric point (pI) of 8.70 and whose abundance in AE was 28.3%. This enzyme was purified to homogeneity using a single-step procedure by cation-exchange chromatography, achieving an 8.1-fold purification and a yield of 16.7%. The peptidase was named pomiferin I and showed a molecular mass of 63,177.77Da. Kinetic constants (KM 0.84mM, Vmax 27.50 uM s-1, kcat 72.37s-1, and kcat/KM 86.15mM-1s-1) were determined employing N-α-carbobenzoxy-L-alanyl-p-nitrophenyl ester as substrate. Analysis by PMF showed only partial homology of pomiferin I with a serine peptidase from a species of the same family.

Antioxidant activities of snakehead (Channa striata) fish skin: peptides hydrolysis using protease tp2 isolate from swamp plant silage

The purpose of this research was to study the antioxidants activities of peptides from skin fish of snakehead (Channa striata), using hydrolysis of protease TP2 isolate from swamp plant silage. This research 5 treatments hydrolysis time (0, 30, 60, 90, 120 min, respectively), with two replicates, which included several stages of preparation and pre-treatment of the snakehead fish skin production of protease enzymes which were isolated from swamp water, preparation of protein hydrolysates, measurement of hydrolysis degrees, analysis of peptides content and analysis of the antioxidant activity. Results showed that the treatment had given a significant effect on the 5% level of the degree of hydrolysis production (13.98% – 27.08%), with peptides content of 2.73% – 3.78% and antioxidant activity (10.75% – 20.7%). The results of the degree of hydrolysis indicate that the longer the hydrolysis time, the percent degree of hydrolysis will increase. Peptide content and antioxidant activity were increased with increasing hydrolysis time.

Effects of ultrasonic, microwave, and combined ultrasonic-microwave pretreatments on the enzymatic hydrolysis process and protein hydrolysate properties obtained from Chinese sturgeon (Acipenser sinensis).

Degree of hydrolysis (DH), yield, amino acid profile, protein solubility, and antioxidant activity of Chinese sturgeon protein hydrolysates, as influenced by thermal pretreatment, ultrasonic (US), microwave (MW), and combined US-microwave pretreatments were investigated. Initially, the samples were subjected to thermal pretreatments in order to measure their effect on DH, which increased at 55°C. The DH recorded 7.63, 5.55, and 6.02% for US, MW, and combined US-MW pretreatment (US+MW), respectively, at the optimal time (8min). The enzymatic hydrolysis (EN) of pretreated samples increased the DH to 19.41, 14.18, and 16.91% for US+EN, MW+EN, and US+MW+EN, respectively. The US+EN treatment was most effective for obtaining higher DH and yield, which were 19.41% and 18.62%, respectively. The use of US+EN also resulted in an increase in the percentage of molecular weights (≤1,000Da), amino acid content and protein solubility, which reached 89.24, 80.08, and 98.58%, respectively. While, US+MW+EN pretreatment has achieved the highest antioxidant activities by IC50 of 1,1-diphenyl-2-picrylhydrazyl and 2,2-Azinobis (3-ehtylbenzothiazoli- 6-sulfnic acid), which were 3.01 and 1.85mg/ml, respectively, in addition to the reducing power assay, which was 0.528 at a protein concentration of 5mg/ml. Therefore, US and combined US-MW techniques can play a promising role in the production of protein hydrolysates and the improvement of their antioxidant properties. PRACTICAL APPLICATIONS: Nowadays, interest in Chinese sturgeon production has increased as a promising source of protein and antioxidant peptides. The optimal thermal pretreatment can be used to enhance the degree of hydrolysis. The results indicated that the use of ultrasound as a pretreatment enhanced the degree of hydrolysis, which could be useful in the preparation of protein hydrolysate with higher yields. The use of combined US-MW significantly improved the antioxidant properties of the protein hydrolysate. The combined US-MW technique is a novel method for obtaining valuable peptides and protein hydrolysates that can be applied as antioxidant constituents in the food products.

Therapeutic and biotechnological applications of substrate specific microbial aminopeptidases

Aminopeptidases (EC 3.4.11.) belongs to exoprotease family, which can catalyze the cleavage of peptide bond which connects the N-terminal amino acid to the penultimate residue in a protein. Aminopeptidases catalyze the process of removal of the N-terminal amino acids of target substrates by sequential cleavage of one amino acid residue at a time. Microbial aminopeptidase are of great acceptance as industrial enzymes with varying applications in food and pharma industry since these enzymes possess unique characteristics than aminopeptidases from other sources. This review describes the various applications of microbial aminopeptidases in different industrial sectors. These enzymes are widely used in food industry as a debittering agent as well as in the preparation of protein hydrolysates. In baking, brewing, and cheese making aminopeptidases are extensively used for removing the bitterness of peptides. The inhibitors of these enzymes are found great clinical applications against various diseases such as cancer, diabetes, and viral infections. Aminopeptidases are widely used for the synthesis of biopeptides and amino acids, and found to be efficient than chemical synthesis. These enzymes are capable of hydrolyzing organophosphate compounds, thus having biological as well as environmental significance.Key Points• Cleaves the amino-terminal amino acid residues from proteins and peptides.• Microbial aminopeptidase are of great acceptance as both therapeutic and industrial enzyme.• Review describes the potential applications of microbial aminopeptidases.

Optimization of pea protein hydrolysate preparation and purification of antioxidant peptides based on an in silico analytical approach

Isolation and purification of peptides by enzymatic hydrolysis may have a significant effect on their antioxidant activity. In the present study, antioxidant peptides were isolated and purified from hydrolysates by digestion of the pea protein with alcalase. Electron paramagnetic resonance (EPR) spectroscopy utilizing the 2,2-diphenyl-1-picrylhydrazyl (DPPH) was used to optimize the preparative protocol. The obtained peptides were identified by nano-LC-ESI-MS/MS and their biological activity was evaluated by the Peptide Ranker method. Our results showed that the second fraction (F1-2) purified from <1 kDa hydrolysate by Sephadex G-25 gel had good antioxidant activity, along with a DPPH radical scavenging rate of 37.94 ± 1.24% and a hydroxyl (OH) radical scavenging rate of 28.43 ± 1.54% (P < 0.05). In addition, the biological activity of the identified peptide sequences was estimated, and three peptides with scores higher than 0.5 were obtained, corresponding to the sequences YSSPIHIW (0.74), ADLYNPR (0.65), and HYDSEAILF (0.53).

Influence of enzymatic hydrolysis conditions on biochemical and antioxidant properties of pacific thread herring (Ophistonema libertate) hydrolysates

ABSTRACT Pacific thread herring (Ophistonema libertate) muscle was hydrolyzed with Alcalase for the preparation of protein hydrolysates. The effect of enzyme concentration (EC; 1% and 3%), pH (8 and 9) and temperature (40°C and 50°C) on some biochemical properties and antioxidant activity (AOXA) was determined. The degree of hydrolysis (DH) ranged between 9.6% and 33.1%. The highest DH was obtained with the following conditons: EC of 3%, pH 9 and temperature of 50°C; however, the highest AOXA measured by DPPH (183.7 µmol TE/mg), FRAP (0.98 µmol TE/mg), and ABTS (144.9 µmol TE/mg) was obtained at EC of 3%, pH 8 and temperature of 50°C. These also exhibited a higher percentage of peptides of MW lower than 1.35 kDa and high concentrations of anionic and cationic amino acids. These results suggest that protein hydrolysates from Pacific thread herring muscle have a potential for application in the formulation of functional food.