ACE-inhibitory Activity Research Articles

In Vitro Multi-Bioactive Potential of Enzymatic Hydrolysis of a Non-Toxic Jatropha curcas Cake Protein Isolate.

The Jatropha curcas cake, a protein-rich by-product of biofuel production, was the subject of our study. We identified and quantified the ACE inhibitory, antioxidant, and antidiabetic activities of bioactive peptides from a Jatropha curcas L. var Sevangel protein isolate. The protein isolate (20.44% recovered dry matter, 38.75% protein content, and 34.98% protein yield) was subjected to two enzyme systems for hydrolysis: alcalase (PEJA) and flavourzyme (PEJF), recording every 2 h until 8 h had passed. The highest proteolytic capacity in PEJA was reached at 2 h (4041.38 ± 50.89), while in PEJF, it was reached at 6 h (3435.16 ± 59.31). Gel electrophoresis of the PEJA and PEJF samples showed bands corresponding to peptides smaller than 10 kDa in both systems studied. The highest values for the antioxidant capacity (DPPH) were obtained at 4 h for PEJA (56.17 ± 1.14), while they were obtained at 6 h for PEJF (26.64 ± 0.52). The highest values for the antihypertensive capacity were recorded at 6 h (86.46 ± 1.85) in PEJF. The highest antidiabetic capacity obtained for PEJA and PEJF was observed at 6 h, 68.86 ± 8.27 and 52.75 ± 2.23, respectively. This is the first report of their antidiabetic activity. Notably, alcalase hydrolysate outperformed flavourzyme hydrolysate and the cereals reported in other studies, confirming its better multi-bioactivity.

IN VITRO AND IN SILICO INHIBITORY ACTIVITY OF ANGIOTENSIN-CONVERTING ENZYME II AND ANTI-INFLAMMATORY EFFECTS OF NATURAL COMPOUNDS FROM RHEUM OFFICINALE ROOTS

Rhubarb roots (Rheum officinale), a common medicinal plant in folk remedies, and their chemical compositions were investigated for their inhibitory activity of angiotensin-converting enzyme II and anti-inflammatory effects by inhibiting NO production and IL-6 expression. Four natural compounds, including two anthraquinones, chrysophanol (2) and emodin (3), and two stilbenes, rhapontigenin (1) and trans-piceatannol (4), were isolated from the roots of Rhubarb. The results showed that rhapontigenin (1) exhibited an inhibitory effect on the ACE-2 enzyme with an IC50 value of 132 mM. In an in silico study, rhapotigenin (1) had a binding energy value of -9.32 kcal/mol, lower than MLN-4760, on ACE-2. Both rhapontigenin (1) and emodin (3) exhibited inhibitory activity on NO production in primary cultures of macrophages RAW264.7, with IC50 values ranging from 5.65 to 32.3 µg/mL. This is the first study of the anti-ACE-2 and anti-inflammatory activity of Rhubarb root extract and its constituents.

Peptidomics and biological activity analysis of in vitro digested Parmigiano Reggiano cheese at different ripening stages

The relationships among Parmigiano Reggiano (PR) cheese ripening, in vitro digestion, and biological activity have been investigated. PR cheese samples at different ripening time (from 12 to 30 months) were collected from two dairies and in vitro digested. No effect of ripening was found when the total peptide profiles were considered. Nevertheless, ripening affected the biological activities and the bioactive peptide profiles of in vitro digested PR. The long-ripened PR samples showed higher ACE-inhibitory and DPP-IV-inhibitory activities after in vitro digestion. The ACE-inhibitory activity of in vitro digested PR samples was positively correlated with the relative amount of potent ACE-inhibitory peptides whereas DPP-IV-inhibitory activity with protein hydrolysis. Some bioactive peptides that, according to the literature, exhibit proven in vivo bioactivity and bioavailable in humans were detected, suggesting their potential role in the protective effects on human health resulting from cheese consumption. PR samples at different ripening time may have potentially different effects on human health.

Antioxidant capacity and peptidomic analysis of in vitro digested Camelina sativa L. Crantz and Cynara cardunculus co-products

In recent decades, the food system has been faced with the significant problem of increasing food waste. Therefore, the feed industry, supported by scientific research, is attempting to valorise the use of discarded biomass as co-products for the livestock sector, in line with EU objectives. In parallel, the search for functional products that can ensure animal health and performances is a common fundamental goal for both animal husbandry and feeding. In this context, camelina cake (CAMC), cardoon cake (CC) and cardoon meal (CM), due valuable nutritional profile, represent prospective alternatives. Therefore, the aim of this work was to investigate the antioxidant activity of CAMC, CC and CM following in vitro digestion using 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), Ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays. Total phenolic content (TPC) and angiotensin converting enzyme (ACE) inhibitory activity, actively involved in modulating antioxidant properties, were also studied. Further, a peptidomic analysis was adopted to substantiate the presence of bioactive peptides after in vitro digestion. The results obtained confirmed an interesting nutritional profile of CAMC, CC and CM and relevant antioxidant and ACE inhibitory activities. In particular, considering antioxidant profile, CM and CC revealed a significantly higher (10969.80 ± 18.93 mg TE/100 g and 10451.40 ± 149.17 mg TE/100 g, respectively; p < 0.05) ABTS value than CAMC (9511.18 ± 315.29 mg TE/100 g); a trend also confirmed with the FRAP assay (306.74 ± 5.68 mg FeSO4/100 g; 272.84 ± 11.02 mg FeSO4/100 g; 103.84 ± 3.27 mg FeSO4/100 g, for CC, CM and CAMC, respectively). Similar results were obtained for TPC, demonstrating the involvement of phenols in modulating antioxidant activity. Finally, CAMC was found to have a higher ACE inhibitory activity (40.34 ± 10.11%) than the other matrices. Furthermore, potentially bioactive peptides associated with ACE inhibitory, anti-hypertensive, anti-cancer, antimicrobial, antiviral, antithrombotic, DPP-IV inhibitory and PEP-inhibitory activities were identified in CAMC. This profile was broader than that of CC and CM. The presence of such peptides corroborates the antioxidant and ACE profile of the sample. Although the data obtained report the important antioxidant profile of CAMC, CC, and CM and support their possible use, future investigations, particularly in vivo trials will be critical to evaluate and further investigate their effects on the health and performance of farm animals.

In Silico Screening of Bioactive Peptides in Stout Beer and Analysis of ACE Inhibitory Activity.

Stout beer was selected as the research object to screen angiotensin-converting enzyme (ACE) inhibitory peptides. The peptide sequences of stout beer were identified using ultra-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry with de novo, and 41 peptides were identified with high confidence. Peptide Ranker was used to score the biological activity and six peptides with a score ≥ 0.5 were screened to predict their potential ACE inhibitory (ACEI) activity. The toxicity, hydrophilicity, absorption, and excretion of these peptides were predicted. In addition, molecular docking between the peptides and ACE revealed a significant property of the peptide DLGGFFGFQR. Furthermore, molecular docking conformation and molecular dynamics simulation revealed that DLGGFFGFQR could be tightly bound to ACE through hydrogen bonding and hydrophobic interaction. Lastly, the ACEI activity of DLGGFFGFQR was confirmed using in vitro evaluation and the IC50 value was determined to be 24.45 μM.

ACE inhibitory activity and gastrointestinal digestion stability of umami peptides IIVFGRQLL from yeast extract

Hypertension has emerged as a major factor detrimental to human health. Umami peptide IIVFGRQLL from yeast has a certain ACE inhibitory activity (IC50: 59.35 μM) at 0.14 mg/mL. Moreover, IIVFGRQLL could regulate the systolic blood pressure of spontaneously hypertensive rats model indicating its potential antihypertensive effect. The changes in ACE inhibitory activity and peptide sequence during the digestion were investigated based on the ACE inhibition assays, simulated gastrointestinal digestion, and LC-MS/MS. The ACE inhibitory activity of IIVFGRQLL decreased by 39.0% after digestion. It was hydrolyzed into 5 peptide fragments, among which IVF took the biggest share followed by IVFG, VF, FGR, and RQL. The inhibitory rate of IVF (78.70%), FGR (86.30%), and VF (83.50%) was higher than that of IIVFGRQLL (60.11%). The molecular docking results revealed all the peptides interacted with active residues related to Zn2+ and S1 pocket in ACE. Besides, IVF, FGR and RQL showed increased electrostatic interaction with Zn2+. These results provide theoretical support for the future exploration of umami peptide as a food additive or seasoning to alleviate hypertension.

Marine sourced tripeptide SRP and its sustained-release formulation SRP-PLGA-MS exhibiting antihypertensive effect in spontaneously hypertensive rats and HUVECs.

Biopeptides from Sipunculus nudus were reported with good ACE inhibitory activity, and the tripeptide SRP was one with the highest ACE inhibition rate. However, the disadvantage of short half-life limited the development of peptide drugs. Moreover, the distinct mechanism of the peptide inhibiting ACE remained unknown. Thus, in this study, a sustained release formulation of SRP-PLGA-MS was designed and prepared. Its long-lasting antihypertensive effect as well as improvement of vascular pathomorphology was verified in spontaneously hypertensive rat (SHR). In addition, the anti-oxidant activity of SRP in human umbilical vein endothelial cells (HUVECs) was evaluated. The results showed that SRP inhibited the production of ROS and NO, which involve the NADPH oxidase, and Keap1/Nrf2 signaling pathway. This study demonstrated that SRP-PLGA-MS had the potential to develop sustained-release drugs for hypertension treatment.

Identification, inhibition modes, and molecular docking of ACE inhibitory peptides derived from Cheddar cheese

Herein, changes in the angiotensin-converting enzyme (ACE) inhibitory activity in Cheddar cheese during ripening (0–8 months) were studied, and the specific inhibitory types and modes of ACE inhibitory peptides were analyzed. The ACE inhibitory activity of Cheddar cheese was highest after 6 months (68.4%), and the ACE inhibitors of water-soluble extracts at this stage were mainly concentrated below 3 kDa. Six peptides with ACE inhibitory activity were isolated and purified from these peptides, and the inhibition modes of these peptides were studied. The results showed that VRYL and YLGY were competitive inhibitory peptides, RYL was a non-competitive inhibitory peptide, and TTMP was a mixed inhibitory peptide. Through the simulation of molecular docking sites, it was found that VRYL formed nine hydrogen bonds in the docking model and exhibited the highest ACE inhibitory activity. This study provides key insights for the development of functional cheeses and the extraction of ACE inhibitory peptides from Cheddar cheese.

Angiotensin-I converting enzyme (ACE) inhibitory bioaccessible peptides obtained from protein extracts of Macrocystis pyrifera and Chondracanthus chamissoi seaweeds

Hypertension is a paramount chronic health concern, underscoring the critical need for preventive measures in public health. In recent years, research has discovered natural anti-hypertensive agents, including those derived from macroalgae. This study focuses on enzymatically hydrolyzing protein extracts from Macrocystis pyrifera and Chondracanthus chamissoi seaweeds to yield angiotensin I-converting enzyme (ACE) inhibitory peptides, potentially applicable in both food and bioactive products. ACE inhibitory activity was evaluated for enzymatic hydrolysates generated using bromelain, papain, and alcalase. Notably, hydrolysates produced using alcalase demonstrated the highest effect, yielding 74 % ACE inhibition for M. pyrifera and 58 % for C. chamissoi protein extracts. Optimization efforts focused on hydrolysis conditions, varying hydrolysis time and substrate-to-enzyme ratio, resulting in peak ACE inhibition of 79.9 % for M. pyrifera (5.3 h, 12.7 S:E ratio) and 70.3 % for C. chamissoi (6 h, 10 S:E ratio).Further analysis explored the relationship between molecular size separation and ACE inhibitory activity in algae hydrolysates. Fractionation via ultrafiltration revealed that fractions below 3 kDa exhibited the highest ACE inhibitory potency. Additionally, in vitro digestion studies employing pepsin and pancreatin treatments demonstrated the bioaccessibility of the seaweed-derived bioactive peptides, with maintained or enhanced bioactivity post-digestion. These findings underscore the potential of protease hydrolysates from M. pyrifera and C. chamissoi as sources of ACE inhibitory activity. Consequently, they present an exciting natural source of functional ingredients or nutraceuticals for hypertension management, with the benefits of easy implementation, profitability, and sustainability in their production process.

Angiotensin-I-converting enzyme and renin inhibitions by antioxidant shrimp shell protein hydrolysate and ultrafiltration peptide fractions

Protein hydrolysates with 20% and 30% degrees of hydrolysis (DH) were produced from alcalase hydrolysis of Pacific white shrimp shells. The study aimed to investigate the antioxidant and antihypertensive activities of these protein hydrolysates, focusing on peptide fractions of various molecular weights (MW) obtained through ultrafiltration. The 30% DH protein hydrolysate (SSPH) showed the highest antioxidant activities and was subjected to ultrafiltration to produce peptides of various molecular weights (MW) (F1:10–50, F2:5–10, F3:3–5, F4:1-3, and F5:<1 kDa). SSPH showed higher hydrophilic and non-essential amino acid content, among which alanine and aspartic acid were at higher levels. The obtained peptide fractions were analyzed for various antioxidant activities and inhibitory activities against angiotensin-converting enzyme and renin. F4 and F2 samples showed the highest DPPH (2.00 mM TE/g sample) and ABTS (60.68 mM TE/g sample) radical scavenging activities, respectively. Superoxide and hydrogen peroxide radical scavenging activity augmented with decreasing MW, aside from for F1, which showed higher activity than F2–F4 (p < 0.05). The highest ACE-inhibitory activity was found for the F2 fraction (44%–55%), and renin inhibitory activity increased with decreasing MW, in which F5 (12%–22%) was the most effective (p < 0.05). F5 showed 6 major peptides, among which KLVRGSKS and LPKKCLSARPG were the dominant sequences. Thus, this study suggests that shrimp shell protein isolate could be an alternative protein source for peptides with various antioxidant and antihypertensive activities, with potential applications in functional foods and nutraceuticals aimed at mitigating oxidative stress and hypertension.

A novel ACE inhibitory peptide from Pelodiscus sinensis Wiegmann meat water-soluble protein hydrolysate

Pelodiscus sinensis meat is a nutritional food and tonic with angiotensin-converting enzyme (ACE) inhibitory activities. To identify the bioactive substances responsible, several bioinformatics methods were integrated to enable a virtual screening for bioactive peptides in proteins identified within a water-soluble protein fraction of Pelodiscus sinensis meat by Shotgun proteomics. The peptides were generated from the identified proteins by in silico proteolysis using six proteases. A comparison of the numbers of proteins suitable for digestion with each enzyme and the iBAQ (intensity-based absolute quantification) values for these proteins revealed that bromelain and papain were the most suitable proteases for this sample. Next, the water solubility, toxicity, and ADMET (absorption/distribution/metabolism/excretion/toxicity) properties of these peptides were evaluated in silico. Finally, a novel ACE inhibitory peptide IEWEF with an IC50 value of 41.33 µM was identified. The activity of the synthesized peptide was verified in vitro, and it was shown to be a non-competitive ACE inhibitor. Molecular docking revealed that IEWEF could tightly bind to C-ACE, and N-ACE with energies less than 0 kJ mol−1, and the peptide IEWEF can form hydrogen bonds with C-ACE and N-ACE respectively. These results provide evidence that bioactive peptides in the water-soluble protein fraction account for (at least) some of the ACE inhibitory activities observed in Pelodiscus sinensis meat. Furthermore, our research provides a workflow for the efficient identification of novel ACE inhibitory peptides from complex protein mixtures.

Evaluation of antioxidant, antimicrobial, and bioactive properties and peptide sequence composition of Malatya apricot kernels.

This study used four different apricot (Prunus armeniaca) kernels cultivated in Malatya during two consecutive years. The varieties were Hacihaliloglu, Hasanbey, Kabaasi, and Zerdali. The physicochemical properties of the kernels were determined, and the bioactive content of the kernels was evaluated using kernel hydrolysates prepared using trypsin. With regard to the physicochemical properties of the kernels, the dry matter ratio and protein content were the highest in the Hacihaliloglu variety; the ash ratio was the highest in the Kabaasi variety, and the free oil ratio was the highest in the Hasanbey variety. The bioactive compound content changed according to kernel variety. Angiotensin-converting enzyme inhibitors activity was found to be the highest in the Hacihaliloglu and Hasanbey varieties, which had the lowest amygdalin content, and Zerdali had the highest amygdalin content. The antioxidant and antimicrobial effects of the kernels varied, with Hasanbey and Kabaasi generally having the highest content in both analyses. Moreover, a concentration of 20 mg mL-1 of the hydrolysate was determined to have a destructive effect for the microorganisms used in this study. The storage protein of the kernels, except Hacihaliloglu, was found to be Prunin 1, with the longest matching protein chain in the kernels being R.QQQGGQLMANGLEETFCSLRLK.E. The results suggest that the peptide sequences identified in the kernels could have antihypertensive, antioxidative, and Dipeptidyl peptidase IV (DPP-IV)inhibitory effects. Consequently, apricot kernels show potential for use in the production of functional food products. Of the kernels evaluated in this study, Hacihaliloglu and Hasanbey were deemed the most suitable varieties due to their higher bioactive content and lower amygdalin content. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Quantitative Structure–Activity Relationship Models for the Angiotensin-Converting Enzyme Inhibitory Activities of Short-Chain Peptides of Goat Milk Using Quasi-SMILES

The inhibitory activity of peptides on angiotensin-converting enzyme (ACE) is a measure of their antihypertensive potential. Quantitative structure–activity relationship (QSAR) models obtained based on the analysis of sequences of amino acids are suggested. The average determination coefficient for the active training sets is 0.36 ± 0.07. The average determination coefficient for validation sets is 0.79 ± 0.02. The paradoxical situation is caused by applying the vector of ideality of correlation, which improves the statistical quality of a model for the calibration and validation sets but is detrimental to the statistical quality of models for the training sets.

Consumption of a Byproduct of Chia Seed Oil Extraction by Cold Pressing Ameliorates Cardiovascular Risks Factors in an Experimental Model of Metabolically Unhealthy Normal Weight.

The byproduct of Salvia hispanica (chia) seed oil extraction by cold pressing, also known as expeller, possesses a high nutritional value. It is rich in proteins, fibers, minerals, and has a residual oil content of 7-11%, which is rich in omega 3 linolenic acid (ALA). However, this byproduct has been historically undervalued. Thus, the aim of current work was to study the effects of consuming of a rich in chia expeller diet on a rabbit model of metabolically unhealthy normal weight to validate their use as a functional food. Rabbits were fed different diets for a period of 6 weeks: a standard diet (CD), a high-fat diet (HFD), a rich in expeller CD (Exp-CD) and a rich in expeller HFD (Exp-HFD). The Exp-HFD attenuated the rise in basal glucose, TyG index, triglycerides, cholesterol and non-HDL cholesterol induced by the HFD. Both rich in expeller diets reduced mean arterial blood pressure (MAP) and increase liver and fat ALA levels compared to their respective controls. Furthermore, the angiotensin converting enzyme (ACE) activity was lower in the lungs of animals fed on rich in expeller diets compared to their respective controls. In vitro studies showed that ALA inhibited ACE activity. The evaluation of vascular reactivity revealed that rich in expeller diets improved angiotensin II affinity and reduced contractile response to noradrenaline. In conclusion, the consumption of rich in expeller diets showed beneficial effects in preventing cardiovascular risk factors such as insulin resistance, dyslipidemia and MAP. Therefore, its use as functional ingredient holds significant promise.

Nicotianamine as a Potential Active Component of Lotus Seed Extract for Inhibiting Angiotensin-converting Enzyme

Aims: Hypertension is one of the chronic diseases causing a serious health problem in many countries worldwide. Therefore, the prevention and amelioration of hypertension with medicinal food is considered to be important for maintaining good health and well-being. The main objective of this study is to verify that the extract of lotus seed has a significant inhibitory effect on the angiotensin I-converting enzyme (ACE). Background: Lotus (Nelumbo nucifera) is well known to have a variety of biological and med-ical activities and is popularly used as a traditional medicinal food in several East Asian coun-tries. In a previous study, we reported that the aqueous extract of lotus root used as a popular foodstuff caused an inhibitory effect on the angiotensin I-converting enzyme (ACE), suggesting its possible effectiveness for improving high blood pressure. Objective: The purpose of the present study was to reveal the effect of lotus seed extract on ACE activity and to identify a potentially active component of the extract originating from lotus seed. Methods: The ACE inhibitory activity was determined using Hippuryl-L-histidyl-L-leucin (HHL) as substrate, and the amount of hippuric acid formed enzymatically was determined using an HPLC system. Results: The lotus seed extract was shown to strongly inhibit the ACE activity, thus ameliorating the hypertensive state. Furthermore, the fractionation of the lotus seed extract provided evidence for suggesting nicotianamine as a putative ACE-inhibiting component contained in the extract. Conclusion: These findings were considered to propose the possibility that the lotus seed and the lotus root might benefit patients with hypertension.

In Silico Study: ACE Inhibitory Activity as a Marine Animal Fatty Acid Antihypertensive Candidate

In Silico Study: ACE Inhibitory Activity as a Marine Animal Fatty Acid Antihypertensive Candidate

In vitro digestibility and angiotensin converting enzyme (ACE) inhibitory activity of solid-state fermented fava beans (Vicia faba L.)

Reducing the content of quickly absorbed carbohydrates and saturated fats in snack formulations while increasing the consumption of high-quality proteins are effective strategies to prevent obesity in childhood. Thus, the nutritional value, digestibility, and functionality of fava beans (Vicia faba L.) fermented with Pleurotus ostreatus were examined as potential ingredients for food design. Solid-state fermentation enhanced the protein content by 16% with a rise in essential (25%) and non-essential (15%) amino acids while decreasing total carbohydrate content and tannin levels. Moreover, fermentation modified the amino acid profile released during digestion, increasing amino acids such as valine, isoleucine, and threonine, which are vital for health and development in childhood. Furthermore, the bioaccessible fraction of the fermented bean showed a 60% of ACE inhibition and improved magnesium bioaccessibility. Consequently, fava beans fermented with Pleurotus ostreatus emerged as a new ingredient in the development of new protein-rich snacks tailored for children and adolescents.

One-step high efficiency separation of prolyl endopeptidase from Aspergillus niger and its application

Prolyl endopeptidase from Aspergillus niger (An-PEP) is an enzyme that recognizes C-terminal peptide bonds of amino acid chains and cleaves them by hydrolysis. An aqueous two-phase system (ATPS) was used to separate An-PEP from fermentation broth. Through single factor experiments, the ATPS containing 16 % (w/w) PEG2000 and 15 % (w/w) (NH4)2SO4 at pH 6.0 obtained the recovery of 79.74 ± 0.16 % and the purification coefficient of 7.64 ± 0.08. It was then used to produce soy protein isolate peptide (SPIP) by hydrolysis of soy protein isolate (SPI), and SPIP-Ferrous chelate (SPIP-Fe) was prepared with SPIP and Fe2+. The chelation conditions were optimized by RSM, as the chelation time was 30 min, chelation temperature was 25 °C, SPIP mass to VC mass was two to one and pH was 6.0. The obtained chelation rate was 82.56 ± 2.30 %. The change in the structures and functional features of SPIP before and after chelation were investigated. The FTIR and UV–Vis results indicated that the chelation of Fe2+ and SPIP depended mainly on the formation of amide bonds. The fluorescence, SEM and amino acid composition analysis results indicated that Fe2+ could induce and stabilize the surface conformation and change the amino acid distribution on the surfaces of SPIP. The chelation of SPIP and Fe2+ resulted in the enhancement of radical scavenging activities and ACE inhibitory activities. This work provided a new perspective for the further development of peptide-Fe chelates for iron supplement.

Modification of Bioactive Properties in Food Protein Hydrolysates by Alcalase and Trypsin

Abstract Background Protein hydrolysates are the fragments of proteins that form during the hydrolysis with promised bioactive properties. Enzymatic hydrolysis produces bioactive peptides with specific amino acid profile. Among all the properties, angiotensin-I converting enzyme (ACE-I) inhibitory activity of the protein hydrolysates attained maximum attention to combat life-threatening disease like hypertension. Methodology In the present study 10 protein-rich food sources (&gt; 20% protein content on dry basis) were used to prepare protein hydrolysates using alcalase and trypsin to investigate the effect of enzymes on ACE-I inhibitory and antioxidant activity. Results Among all the sources, the highest degree of hydrolysis was observed in sardine (62.89%) followed by soybean (61.24%) when hydrolyzed by alcalase. Kidney pea exhibited highest ACE-I inhibitory activity with IC50 value of 0.517 and 0.521 when hydrolyzed using both trypsin and alcalase, respectively. All the sources selected showed nonsignificant changes in ACE-I inhibitory activity between alcalase and trypsin (p &lt; 0.05) except Bengal gram and chicken. Antioxidant activity was higher in alcalase hydrolyzed egg yolk (43.08%). Conclusion Among the sources, all animal proteins hydrolyzed using alcalase exhibited significantly higher (p &lt; 0.05) antioxidant activity than trypsin. However, protein hydrolysates prepared from sardine using alcalase would yield bioactive peptides with higher ACE-I inhibitory and antioxidant activity. Therefore, use of alcalase as a substitution for trypsin would be economical for large-scale production. Henceforth, food protein hydrolyzed by alcalase can be used as a functional ingredient for the development of functional or nutraceutical foods to combat lifestyle diseases.

AN INVESTIGATION OF THE ACE INHIBITORY ACTIVITY, ANTIOXIDANT CAPACITY, AND PHYTOCHEMICAL CONSTITUENTS OF POLAR AND NON-POLAR EXTRACTS OF ZIZIPHUS JUJUBA FRUIT: STATISTICAL SCREENING THE MAIN COMPONENTS RESPONSIBLE FOR BIOACTIVITY

Herein, the angiotensin I-converting enzyme (ACE) inhibitory activity, antioxidant capacity, total polyphenol contents (TPC), and phytochemical profiles of polar and non-polar extracts of dried Ziziphus jujuba fruits were investigated, along with the statistical determination of the main components responsible for ACE inhibitory activity. The non-polar extract expressed the strongest ACE inhibitory activity (99.81%) among the extracts. The non-polar extract also exhibited the highest DPPH scavenging activity (IC50 of 30.63), linoleic acid/β-carotene bleaching capacity (89.31%), and TPC (59.47 mg GAE/g). The phenolic profiles of the extracts were identified by LC-MS/MS, and the presence of seven triterpenoid species in the extracts was examined using GC-MS techniques. The principal constituents included 19 phenolics, 2 organic acids, and 4 triterpenoids. A Pearson correlation and principal component analysis were conducted to find the correlation between individual phenolic compounds and ACE inhibitory activity.