Effect of Protease Type and Peptide Size on the In Vitro Antioxidant, Antihypertensive and Anti-Diabetic Activities of Eggplant Leaf Protein Hydrolysates

Solanum macrocarpon (eggplant) leaf protein isolate (ELI) was hydrolyzed using four different enzymes to produce hydrolysates from alcalase (AH), chymotrypsin (CH) pepsin (PH) and trypsin (TH). CH had an overall stronger antioxidant property and was separated using ultrafiltration membranes into <1, 1–3 and 3–5 kDa peptide fractions. Gel-permeation chromatography confirmed conversion of the ELI (average of 22 kDa) into protein hydrolysates that contained smaller peptides (<6 kDa). A total of 23 peptides consisting of tri and tetrapeptides were identified from the CH, which is a wider spectrum when compared to seven for AH and four each for TH and PH. CH exhibited stronger scavenging activities against DPPH and hydroxyl radicals. CH and TH exhibited the strongest inhibitions against angiotensin-converting enzyme. In contrast, AH was the strongest inhibitor of α-amylase while AH and PH had strong inhibitory activities against α-glucosidase when compared with other hydrolysates. Ultrafiltration fractionation produced peptides that were stronger (p < 0.05) scavengers of DPPH, and hydroxyl radicals, in addition to better metal-chelating and enzyme inhibition agents. The study concluded that the eggplant protein hydrolysates and the UF fractions may find applications in tackling oxidative stress-related diseases and conditions involving excessive activities of the metabolic enzymes.

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In Vitro Characterization of Fluted Pumpkin Leaf Protein Hydrolysates and Ultrafiltration of Peptide Fractions: Antioxidant and Enzyme-Inhibitory Properties

Polish Journal of Food and Nutrition Sciences ◽

10.31883/pjfns/130401 ◽

2020 ◽

Vol 70 (4) ◽

pp. 429-443

Author(s):

Akinsola Famuwagun ◽

Adeola Alashi ◽

Saka Gbadamosi ◽

Kehinde Taiwo ◽

Joseph Oyedele ◽

...

Keyword(s):

Protein Hydrolysates ◽

Leaf Protein ◽

Fluted Pumpkin ◽

In Vitro Characterization ◽

Peptide Fractions

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Identification and Characterization of Novel Antioxidant Protein Hydrolysates from Kiwicha (Amaranthus caudatus L.)

Antioxidants ◽

10.3390/antiox10050645 ◽

2021 ◽

Vol 10 (5) ◽

pp. 645

Author(s):

Sergio Montserrat-de la Paz ◽

Alicia Martinez-Lopez ◽

Alvaro Villanueva-Lazo ◽

Justo Pedroche ◽

Francisco Millan ◽

...

Keyword(s):

Antioxidant Capacity ◽

Reducing Power ◽

Protein Isolate ◽

Protein Hydrolysates ◽

Antioxidant Peptides ◽

Amaranthus Caudatus ◽

Intact Proteins ◽

Identification And Characterization

Kiwicha (Amaranthus caudatus) is considered one of the few multipurpose pseudocereals for its potential use not only as a source of nutrients and fiber but also for its bioactive compounds. In recent years, antioxidant peptides are commonly used as functional ingredient of food. Herein, a kiwicha protein isolate (KPI), obtained from kiwicha defatted flour (KDF), was hydrolyzed by Bioprotease LA 660, a food-grade endoprotease, under specific conditions. The resulting kiwicha protein hydrolysates (KPHs) were chemically characterized and their digestibility and antioxidant capacity were evaluated by in vitro cell-free experiments owing to their measure of capacity to sequester DPPH free radical and reducing power. KPHs showed higher digestibility and antioxidant capacity than intact proteins into KPI. Therefore, the results shown in this study indicate that KPHs could serve as an adequate source of antioxidant peptides, representing an effective alternative to the generation of functional food.

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Antioxidant and antihypertensive activities of wonderful cola (Buchholzia coriacea) seed protein and enzymatic protein hydrolysates

Journal of Food Bioactives ◽

10.31665/jfb.2018.3156 ◽

2018 ◽

Vol 3 ◽

pp. 133-143 ◽

Cited By ~ 5

Author(s):

Oluwole S. Ijarotimi ◽

Sunday A. Malomo ◽

Adeola M. Alashi ◽

Ifeanyi D. Nwachukwu ◽

Tayo N. Fagbemi ◽

...

Keyword(s):

Blood Pressure ◽

Protein Hydrolysate ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Protein Isolate ◽

Active Inhibitor ◽

Spontaneously Hypertensive ◽

Reducing Ability ◽

Peptide Fractions

The aim of this work was to produce wonderful cola protein hydrolysate fractions with in vitro antioxidant properties coupled with blood pressure-reducing ability when orally administered to spontaneously hypertensive rats (SHRs). Wonderful cola protein isolate (WCI) was hydrolyzed with pancreatin to produce a hydrolysate (WCH), which was subjected to ultrafiltration separation using 1, 3, 5, and 10 kDa molecular weight cut-off membranes to obtain <1, 1–3, 3–5 and 5–10 kDa peptide fractions, respectively. The <1 and 1–3 kDa fractions had higher contents of arginine when compared to the 3–5 and 5–10 kDa peptides. The WCH and <1 kDa peptide fraction had significantly (p < 0.05) better DPPH radical scavenging (55–67%) and metal chelation (83–93%) activities but lower hydroxyl radical scavenging power (10–32%) than the WCI (46, 46 and 63%, respectively). The <1 kDa had significantly (p < 0.05) higher in vitro inhibition (80%) of angiotensin converting enzyme (ACE) activity while the 5–10 kDa was the most active inhibitor (90%) of renin activity. All peptide fractions so produced had better systolic and diastolic blood pressure-lowering effects than WCH and WCI. However, the <1 kDa fraction produced significantly (p < 0.05) stronger systolic (−33 mmHg) and diastolic (−30 mmHg) blood pressure reductions 6 h after oral gavage to SHRs. Thus, wonderful cola proteins contain encrypted bioactive peptides that may be used to formulate antioxidant and antihypertensive products.

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Effect of Carboxymethylation and Phosphorylation on the Properties of Polysaccharides from Sepia esculenta Ink: Antioxidation and Anticoagulation in Vitro

Marine Drugs ◽

10.3390/md17110626 ◽

2019 ◽

Vol 17 (11) ◽

pp. 626 ◽

Cited By ~ 1

Author(s):

Liu ◽

Li ◽

Luo

Keyword(s):

Hydroxyl Radicals ◽

Sodium Tripolyphosphate ◽

Orthogonal Experiment ◽

Antioxidant Property ◽

Thrombin Time ◽

Sodium Trimetaphosphate ◽

Sepia Esculenta ◽

Dose Dependent Fashion ◽

Ic50 Values

To investigate the effect of carboxymethylation and phosphorylation modification on Sepia esculenta ink polysaccharide (SIP) properties, this study prepared carboxymethyl SIP (CSIP) with the chloracetic acid method, and phosphorylated SIP (PSIP) with the sodium trimetaphosphate (STMP)/sodium tripolyphosphate (STPP) method, on the basis of an orthogonal experiment. The in vitro antioxidant and anticoagulant activities of the derivatives were determined by assessing the scavenging capacity of the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals, which activated the partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results showed that SIP was modified successfully to be CSIP and PSIP, and degrees of substitution (DSs) of the two products were 0.9913 and 0.0828, respectively. Phosphorylation efficiently improved the antioxidant property of SIP, and the IC50 values of PSIP on DPPH and hydroxyl radicals decreased by 63.25% and 13.77%, respectively. But carboxymethylation reduced antioxidant activity of the native polysaccharide, IC50 values of CSIP on the DPPH and hydroxyl radicals increased by 16.74% and 6.89%, respectively. SIP significantly prolonged the APTT, PT, and TT in a dose-dependent fashion, suggesting that SIP played an anticoagulant action through intrinsic, extrinsic, and common coagulation pathways. CSIP and PSIP both possessed a stronger anticoagulant capacity than SIP via the same pathways; moreover, CSIP was observed to be more effective in prolonging APTT and PT than PSIP.

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Angiotensin-converting enzyme inhibitory effects of dairy- and soy-derived peptides in pre-hypertensive overweight men and women

Functional Foods in Health and Disease ◽

10.31989/ffhd.v3i1.78 ◽

2013 ◽

Vol 3 (1) ◽

pp. 37

Author(s):

Melissa S. Munn ◽

Shalamar Sibley ◽

Richard Brundage ◽

Baraem Ismail ◽

Carrie P. Earthman

Keyword(s):

Blood Pressure ◽

Whey Protein ◽

Soy Protein ◽

Protein Hydrolysate ◽

Protein Isolate ◽

Protein Hydrolysates ◽

Ace Activity ◽

Soy Protein Hydrolysates ◽

Ace Inhibitory

Background: Hypertension is considered the most prevalent cardiovascular disorder and a significant public health problem. A functional food that could potentially impede progression into a hypertensive state in pre-hypertensive individuals is of significant interest to clinicians and consumers. In vitro and animal studies suggest the presence of potential ACE inhibitory dairy-and soy-derived peptides. Very few human-based research studies have been conducted to investigate the blood pressure lowering and/or ACE-inhibitory effects of whey and soy protein hydrolysates in humans. This pilot study tested the acute effects of 20g doses of whey and soy hydrolysates in pre-hypertensive, overweight men and postmenopausal women on serum ACE activity and blood pressure. Findings: Using a randomized crossover design, four initial subjects received five treatments (unhydrolyzed casein, whey protein isolate, whey protein hydrolysate, soy protein isolate, soy protein hydrolysate) at different testing visits separated by three-day washout periods. Blood pressure and blood draws to measure ACE activity were taken at thirty minute intervals following treatment consumption. Both the soy protein and whey protein hydrolysates had notable in vitro ACE-inhibitory activity, both before and after heat treatment. No differences were observed among the protein treatments for either ACE activity or systolic blood pressure. Conclusions: The results of this pilot study support a discrepancy between in vitro and human-based in vivo ACE-inhibitory acute effects of whey and soy protein hydrolysates, underscoring the need for further research to better understand potential explanations for these findings. Key Words: ACE (Angiotensin-converting enzyme), Casein, Soy, Whey, Protein, Blood pressure, Dairy, Bioactive, Peptides

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Pigeon pea enzymatic protein hydrolysates and ultrafiltration peptide fractions as potential sources of antioxidant peptides: An in vitro study

LWT ◽

10.1016/j.lwt.2018.07.003 ◽

2018 ◽

Vol 97 ◽

pp. 269-278 ◽

Cited By ~ 18

Author(s):

Aderonke I. Olagunju ◽

Olufunmilayo S. Omoba ◽

Victor N. Enujiugha ◽

Adeola M. Alashi ◽

Rotimi E. Aluko

Keyword(s):

In Vitro Study ◽

Pigeon Pea ◽

Protein Hydrolysates ◽

Vitro Study ◽

Antioxidant Peptides ◽

Potential Sources ◽

Peptide Fractions

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Enzymatic protein hydrolysates and ultrafiltered peptide fractions from Cowpea Vigna unguiculata L bean with in vitro antidiabetic potential

Journal of the Iranian Chemical Society ◽

10.1007/s13738-019-01651-0 ◽

2019 ◽

Vol 16 (8) ◽

pp. 1773-1781 ◽

Cited By ~ 5

Author(s):

Eduardo Castañeda-Pérez ◽

Karina Jiménez-Morales ◽

Carlos Quintal-Novelo ◽

Rosa Moo-Puc ◽

Luis Chel-Guerrero ◽

...

Keyword(s):

Vigna Unguiculata ◽

Protein Hydrolysates ◽

Peptide Fractions

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PHYTOCHEMICALS, ANTIOXIDANT ACTIVITY AND PHENOLIC PROFILING OF DIPLOCYCLOS PALMATUS (L.) C. JEFFERY

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i4.16891 ◽

2017 ◽

Vol 9 (4) ◽

pp. 101 ◽

Cited By ~ 2

Author(s):

Usmangani A. Attar ◽

Savaliram G. Ghane

Keyword(s):

Radical Scavenging Activity ◽

Radical Scavenging ◽

Antioxidant Property ◽

Reversed Phase ◽

Antioxidant Potential ◽

Antioxidant Compounds ◽

Fruit Extract ◽

Metal Chelating ◽

Rp Hplc

Objective: The aim of this study was to analyze phytochemicals, antioxidant potential and phenolic profiling of leaf and fruit extracts of Diplocyclos palmatus.Methods: The leaves and fruits were subjected for sequential extraction with hexane, chloroform, methanol and water. All extracts were subjected to biochemical studies such as phenols, tannins, flavonoids, terpenoids and antioxidant assays such as 1,1-diphenyl-1-picryl hydrazyl (DPPH), 2,2’ Azinobis (3-ethyl-benzothiozoline-6-sulfonic acid (ABTS), ferric reducing antioxidant property (FRAP), metal chelating and phospho- molybdenum reduction assay. Further methanolic extract was used for phenolics characterization by reversed phase-high performance liquid chromatography (RP-HPLC).Results: It was observed that methanol fruit extract showed significantly higher phenolics (9.29±0.01 mg tannic acid equivalent (TAE)/g extract), flavonoids (15.02±0.96 mg catechin equivalent (CE)/g extract) and terpenoids (276.73±0.76 mg ursolic acid equivalent (UAE)/g extract). However, chloroform extracts of leaf and fruit exhibited a high amount of tannins (22.07±0.06, 6.99±0.10 mg CE/g extract) respectively. The extracts were subjected to assess their antioxidant potential using various in vitro systems such as DPPH, ABTS, FRAP, metal chelating and phospho- molybdenum reduction. Among the various extracts, methanol fruit extract had highest DPPH radical scavenging activity (26.73±0.14 mg ascorbic acid equivalent (AAE)/g extract), metal chelating activity (0.80±0.01 mg EDTA equivalent (EE)/g extract) and phospho- molybdenum activity (291.24±2.19 mg AAE/g extract). In ABTS radical scavenging assay, aqueous leaf extract (12.11±0.07 mg trolox equivalent (TE)/g extract) showed the best response. The effective ferric reducing antioxidant property (141.54±10.12 mg Fe (II)/g extract) was exhibited by aqueous fruit extract. Overall, methanol and water were found to be the best solvents for the extraction of antioxidant compounds from fruit and leaf. In the RP-HPLC analysis, the major bioactive phenolic compounds such as catechin (CA) and hydroxybenzoic acid (HBA) were recorded in leaf as compared to fruit. In leaf, CA and chlorogenic acid (CLA) were principal compounds in leaf and fruit respectively. However, gallic acid (GA), HBA, CLA and vanillic acid (VA) were widespread in leaf and fruit. Conclusion: On the basis of the results, it was found that D. palmatus may serve as a novel and rich source of natural antioxidants and it can be further explored for pharmaceutical purposes.

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Bioactive Peptides from Germinated Soybean with Anti-Diabetic Potential by Inhibition of Dipeptidyl Peptidase-IV, α-Amylase, and α-Glucosidase Enzymes

International Journal of Molecular Sciences ◽

10.3390/ijms19102883 ◽

2018 ◽

Vol 19 (10) ◽

pp. 2883 ◽

Cited By ~ 22

Author(s):

Marcela González-Montoya ◽

Blanca Hernández-Ledesma ◽

Rosalva Mora-Escobedo ◽

Cristina Martínez-Villaluenga

Keyword(s):

Soybean Protein ◽

Dipeptidyl Peptidase ◽

Structural Features ◽

Protein Isolate ◽

Dipeptidyl Peptidase Iv ◽

Dpp Iv ◽

Phase Liquid ◽

Peptide Fractions ◽

Germinated Soybean

Functional foods containing peptides offer the possibility to modulate the absorption of sugars and insulin levels to prevent diabetes. This study investigates the potential of germinated soybean peptides to modulate postprandial glycaemic response through inhibition of dipeptidyl peptidase IV (DPP-IV), salivary α-amylase, and intestinal α-glucosidases. A protein isolate from soybean sprouts was digested by pepsin and pancreatin. Protein digest and peptide fractions obtained by ultrafiltration (<5, 5–10 and >10 kDa) and subsequent semipreparative reverse phase liquid chromatography (F1, F2, F3, and F4) were screened for in vitro inhibition of DPP-IV, α-amylase, maltase, and sucrase activities. Protein digest inhibited DPP-IV (IC50 = 1.49 mg/mL), α-amylase (IC50 = 1.70 mg/mL), maltase, and sucrase activities of α-glucosidases (IC50 = 3.73 and 2.90 mg/mL, respectively). Peptides of 5–10 and >10 kDa were more effective at inhibiting DPP-IV (IC50 = 0.91 and 1.18 mg/mL, respectively), while peptides of 5–10 and <5 kDa showed a higher potency to inhibit α-amylase and α-glucosidases. Peptides in F1, F2, and F3 were mainly fragments from β-conglycinin, glycinin, and P34 thiol protease. The analysis of structural features of peptides in F1–F3 allowed the tentative identification of potential antidiabetic peptides. Germinated soybean protein showed a promising potential to be used as a nutraceutical or functional ingredient for diabetes prevention.

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