Antihypertensive Bioactive Peptides Research Articles

Molecular binding mechanism and novel antidiabetic and anti-hypertensive bioactive peptides from fermented camel milk with anti-inflammatory activity in raw macrophages cell lines.

The investigation was to determine the effect of camel milk fermented with Limosilactobacillus fermentum KGL4 (MTCC 25515) on ACE-inhibiting, anti-inflammatory, and diabetes-preventing properties and also to release the novel peptides with antidiabetic and anti-hypertensive attributes with molecular interaction studies. Growth conditions were optimised on the basis of total peptide production by inoculating the culture in camel milk at different rates (1.5, 2.0, and 2.5%) along with different incubation periods (12, 24, 36, and 48h). However, after 48h of fermentation with a 2.5% rate of inoculum, the highest proteolytic activity was obtained. Reverse phase high-pressure liquid chromatography (RP-HPLC) was used to calculate the % Rpa from permeates of 3kDa and 10kDa fractions. Molecular weight distributions of fermented and unfermented camel milk protein fractions were compared using SDS-PAGE. Spots obtained from 2D gel electrophoresis were separated on the basis of pH and molecular weight. Spots obtained from 2D gel were digested with trypsin, and the digested samples were subjected to RP-LC/MS for the generation of peptide sequences. The inhibition of tumour necrosis factor alpha, interleukin-6, and interleukin-1 during fermentation was studied using RAW 264.7 macrophages. In the study, fermented camel milk with KGL4 (CMKGL4) inhibited LPS-induced nitric oxide (NO) production and pro-inflammatory cytokine production (TNF-α, IL-6, and IL-1β) by the murine macrophages. The results showed that the peptide structures (YLEELHRLNK and YLQELYPHSSLKVRPILK) exhibited considerable binding affinity against hPAM and hMGA during molecular interaction studies.

Identification of antihypertensive bioactive peptides in the herby and white cheeses produced from different milk types

Identification of antihypertensive bioactive peptides in the herby and white cheeses produced from different milk types

Fast Skeletal Muscle Troponin and Tropomyosin as a Dietary Source of Antidiabetic and Antihypertensive Bioactive Peptides: An In Silico Study

Background : The nutraceutical properties of food hydrolysates rely on multiple biochemical interactions involving the modulation of enzymes and cellular receptors. Numerous bioactive peptides released from troponin and tropomyosin digestion have been identified. Their characterization has mostly been performed by hydrolysis catalyzed by proteases unrelated to the human digestive system. Objective: This study aimed to determine the bioactive profile of beef, pork, and chicken meat by analyzing the frequency and pharmacokinetics of biopeptides released from troponin and tropomyosin. Methods: In silico digestion and biopeptide release frequency were studied by three parameters; bioactive fragments release frequency (AE), frequency percentage (W), and mean occurrence (AS), all stated on the BIOPEP-UWM platform. Further on, hydrolysis end-products were screened based on gastrointestinal-absorption probability and pharmacokinetic profiling performed on SwissADME, SwissTargetPrediction, and ADME/Tlab bioinformatics web tools. Statistical analyses were performed using a one-way ANOVA test. Results: Dipeptidyl peptidase-IV (DPP-IV) and angiotensin-converting enzyme (ACE) inhibiting biopeptides exhibited the highest release frequency. Moreover, W and AS parameters showed no significant difference (p>0.05) between the myofibrillar isoforms assessed. Seven biopeptides were classified as highly absorbable and reported optimal drug-likeness compliance. Although biopeptides hold good pharmacokinetic properties, the therapeutic potency of biopeptides showed to be lower than those of DPP-IV and ACE-inhibiting drugs. Conclusions: Troponin and tropomyosin are rich dietary sources of bioactive peptides, mainly DPP-IV and ACE inhibitors. Digestion end-products are mainly dipeptides with optimal pharmacokinetic and drug-like properties, suggesting a potential therapeutic application in hypertensive and hyperglycemic disorders.

Antioxidant and Anti-hypertensive Bioactive Peptides from Indian Mackerel Fish Waste

Antioxidant and Anti-hypertensive Bioactive Peptides from Indian Mackerel Fish Waste

Isolation and characterization of antihypertensive peptides from soy bean protein

Proteins and peptides are the most diverse biomolecules found in nature and make our interest due to their wide applications in food and pharmaceutical industry. Angiotensin Converting Enzyme (ACE) plays a major role in controlling blood pressure. The inhibition of ACE with peptides is a main target in the regulation of hypertension. The objective of the present study was to investigate the therapeutic potential of soy bean. This was accomplished by isolation of ACE inhibitory peptides using response surface methodology (RSM) and characterization of these bioactive peptides by mass spectrometry. 31 hydrolyzed fractions were isolated and evaluated for their ACE inhibition potential. Hydrolyzed fraction having highest ACE inhibitory activity was characterized by liquid chromatography-mass spectrometry (LC-MS) technique. RSM results showed maximum ACE inhibition potential (64%) by hydrolyzate was obtained at 45 oC temperature, pH 8.0, E/S 0.2 in 2 hours hydrolysis time. Results of LC-MS analysis revealed Ser-Gly, Ser-Pro, Met-Ala, His-Ala, Lys-Pro, Phe-Thr, Met-Leu, Pro-Arg, Ala-Pro-Val, Pro-Ala-Leu, Val-Met-Gly, Pro-Leu-Val, Pro-Pro-Gln, His-Arg-Gly, Ser-Phe-Val-Leu, Ala-Val-His-Try, Arg-Thr-Val-Arg, His-His-Tyr-Leu-Val, Asp-Gly-Ala-Cys-Ser-Ala-Asn and MetVal-Thr-Gly-Pro-Gly-Cys-His bioactive peptides in hydrolyzed fraction of soy bean. Our data provide evidence that response surface methodology is a good approach for isolation of antihypertensive bioactive peptides with more potent activity as nutraceuticals or pharmaceuticals. Therefore soy bean can be use for industrial production of pharmaceutical grade natural medicines for handling high blood pressure.

Angiotensin-converting enzyme inhibitor activity of peptides derived from Kacang goat skin collagen through thermolysin hydrolysis.

Background and Aim:Angiotensin-converting enzyme (ACE) is one of the inhibitory enzymes isolated from animals for the treatment of hypertension. ACE inhibitor (ACE-I) peptides can be obtained by hydrolyzing proteins from various animal tissues, including muscle and connective tissues. However, the study on ACE-I activity from collagen of Kacang goat skin has not been conducted. This study explores the potency of collagen from Kacang goat skin as a source of an antihypertensive agent through ACE inhibition. Thermolysin will hydrolyze collagen and produce the peptide classified antihypertensive bioactive peptides. This study aimed to determine the potential of thermolysin to hydrolyze collagen of Kacang goat skin for ACE-I peptide production and to identify the production of ACE-I peptides.Materials and Methods:Collagen from Kacang goat skin was hydrolyzed with thermolysin and incubated at 37°C for 1 h. Molecular weight (MW) evaluation was performed by SDS PAGE; fractionation peptides at <5 kDa, 3-5 kDa, and <3 kDa were performed by ultrafiltration and ACE-I activity determined by IC50 measurement.Results:Collagen was hydrolyzed by thermolysin, resulting in protein with MW of 117.50-14.60 kDa. The protein content of fractionation at >5 kDa was 3.93±0.72 mg/mL, content of 3-5 kDa was 3.81±0.68 mg/mL, and that of <3 kDa was 2.33±0.38 mg/mL. Fractionation was performed 3 times and one of the results was selected for the ACE-I test. The selected fraction was tested by IC50 measurement with three repetitions and it showed an average enzyme activity at 0.83 mg/mL or 82.94 mg/mL.Conclusion:Thermolysin hydrolysis of collagen from Kacang goat skin showed the potential to produce bioactive peptides, such as ACE-I.

Multifunctional bioactive peptides derived from quinoa protein hydrolysates: Inhibition of α-glucosidase, dipeptidyl peptidase-IV and angiotensin I converting enzymes

The study aimed to characterize and identify anti-diabetic and anti-hypertensive bioactive peptides generated upon enzymatic hydrolysis of quinoa protein isolates. Different quinoa protein hydrolysates (QPHs) were produced using food grade enzymes like Bromelain, chymotrypsin and Pronase E at a hydrolysis interval of 2 h up to 6 h. QPHs were characterized for their physicochemical properties using degree of hydrolysis, SDS-PAGE, and their anti-diabetic properties via inhibition of dipeptidyl peptidase-IV (DPP-IV) and α-glucosidase (AG), and anti-hypertensive property via inhibition of angiotensin converting enzyme (ACE) were explored. IC50 for DPP-IV, AG and ACE inhibitory activities of QPHs were in the range of 0.72–1.12, 1.00–1.86 and 0.18–0.31 mg/mL, respectively. The chymotrypsin derived 6 h hydrolysate (QC6) was sequenced for peptides identification and 136 peptides were identified among which 35 peptides were predicted as potential bio-active peptides (BAPs) based on their Peptide Ranker score. Results showed that identified peptides were predicted to possess high potential in inhibiting the DPP-IV, AG and ACE. In particular, QHPHGLGALCAAPPST was found to bind to the highest number of active hotspots of the target enzymes that are involved in their enzymatic activities. In conclusion, quinoa protein hydrolysates were identified as potential sources of BAPs with inhibitory properties towards key enzymes involved in the control of type 2 diabetes and hypertension.

Anti-hypertensive and angiotensin-converting enzyme inhibitory effects of Radix Astragali and its bioactive peptide AM-1

Ethnopharmacological relevanceHypertension is one of the common chronic health problems in the world. Astragalus membranaceus root (AM), also known as Huangqi, is a popular medicinal herb traditionally used to reinforce vital energy and modulate hypertension.Aim of the study: This study was to reveal the anti-hypertensive activities and mechanisms of AM in spontaneously hypertensive rats (SHRs). Moreover, the presence of bioactive components in AM was further identified. Materials and methodsWe analyzed the effects of aqueous extract of AM (AME) on the regulation of blood pressure and angiotensin converting enzyme (ACE), the major target of anti-hypertensive drugs. Proteomic, bioinformatics, and docking analyses were performed to identify the anti-hypertensive bioactive peptides in AME. ResultsOur data showed that AME inhibited ACE activities in a dose-dependent manner, with an IC50 of 1.85 ± 0.01 μg/ml. In comparison with mock, oral administration of AME reduced systolic blood pressure (SBP) levels in SHRs, and the level of SBP was decreased by 22.33 ± 3.61 mmHg at 200 mg/kg AME. Proteomic analysis identified that an abundant 152-amino-acid putative protein kinase fragment accounted for approximately 11.7% of protein spots in AME. AM-1 (LVPPHA), a gastrointestinal enzyme-resistant peptide cleaved from putative protein kinase fragment, inhibited ACE activities, with an IC50 value of 414.88 ± 41.88 μM. Moreover, oral administration of AM-1 significantly decreased SBP levels by 42 ± 2.65 mmHg at 10 μmol/kg. Docking analysis further showed that AM-1 docked into the active site channel of ACE and interacted with Ala-354 in the active site pocket of ACE. Conclusionsthe ACE inhibitory effect of AM and the presence of ACE inhibitory phytopeptide in AME supported the ethnomedical use of AM on hypertension.

Angiotensin-I-converting enzyme inhibitory peptides in milk fermented by indigenous lactic acid bacteria.

Background and Aim:Fermented milk can be used to produce antihypertensive peptides. Lactic acid bacteria (LAB) with its proteolytic system hydrolyze milk protein during fermentation to produce several peptides, which include antihypertensive bioactive peptides. This study aimed to investigate the ability of indigenous LAB for the production of angiotensin-I-converting enzyme inhibitory (ACE-I) peptides in fermented milk and to characterize the ACEI peptides.Materials and Methods:Reconstituted milk (11%) inoculated with ten LAB isolates, and then incubated at 37°C until it reaches pH 4.6. The evaluation was carried out for LAB count, lactic acid concentration, peptide content, and ACE-I activity. The low molecular weight (MW) peptides (<3 kDa) were identified using Nano LC Ultimate 3000 series system Tandem Q Exactive Plus Orbitrap high-resolution mass spectrometry.Results:The result showed that the ten LAB isolates were able to produce ACE-I in fermented milk with the activities in the range of 22.78±2.55-57.36±5.40%. The activity of ACE-I above 50% produced by Lactobacillus delbrueckii BD7, Lactococcus lactis ssp. lactis BD17, and Lactobacillus kefiri YK4 and JK17, with the highest activity of ACE-I produced by L. kefiri YK4 (IC50 0.261 mg/mL) and L. kefiri JK17 (IC50 0.308 mg/mL). Results of peptide identification showed that L. kefiri YK 4 could release as many as 1329, while L. kefiri JK 17 could release 174 peptides. The peptides produced were 95% derived from casein. The other peptides were from ά-lactalbumin, β-lactoglobulin, and serum amyloid A. The peptides produced consisted of 6-19 amino acid residues, with MWs of 634-2079 Dalton and detected at 317-1093 m/z. A total of 30 peptides have been recognized based on literature searches as ACE-I peptides (sequence similarity: 100%).Conclusion:L. kefiri YK4 and JK17 are the potential to be used as starter cultures to produce the bioactive peptide as ACE-I in fermented milk.

ACE Inhibitory and Antioxidative Bioactive Peptides Derived from Hydrolyzed Soy Milk

Soy milk is a soybean processed product rich in protein as well as sources of bioactive peptides. Bioactive peptides defined as specific protein fragments that have a positive impact on body functions and conditions and may ultimately influence health. This study was conducted to explore the potential of hydrolyzed soy milk as a source of antioxidative and antihypertensive bioactive peptides through enzymatic hydrolysis. The initial treatment of soy milk protein was acidic precipitation with hydrochloric acid. Furthermore, protein precipitate was hydrolyzed using pepsin proteolytic enzyme with an enzyme: substrate ratio (1:5, 1:10 and 1:20). Protein hydrolysis was carried out for 0–48 hours at 37 °C in an acetate buffer pH 4.5. The soy milk protein hydrolysates were subjected to determination of % DH (Degree of Hydrolysis) and protein profile by SDS-PAGE (sodium dodecyl sulphate polyacrylamide gel electrophoresis). The antihypertensive assay was carried out by in vitro inhibition of the ACE enzyme (Angiotensin Converting Enzyme) and antioxidative activity assay using the DPPH method. The results showed that the optimum conditions for hydrolysis of soy milk were obtained at 40 hours with a % DH value of 53.24% in enzyme ratio 1:20 and the highest antihypertensive activity was obtained from 48 hours hydrolysis with % ACE inhibition value of 79.31%. The highest antioxidative activity of bioactive peptide was obtained at hydrolysis 48 hours with IC50 69.1034 µg / ml. After fractionated and LCMS characterized it was obtained 2 bioactive peptides with molecular weights of 8.954 and 2,696 kDa. These bioactive peptides from hydrolyzed of soymilk might be potential as an antihypertensive agent and reduce oxidative stress.

PENDUGAAN PEPTIDA BIOAKTIF DARI SUSU TERHIDROLISIS OLEH PROTEASE TUBUH DENGAN TEKNIK IN SILICO

The production of bioactive peptides catalyzed by gastrointestinal system (GIS) enzymes can be predicted in silico. The technique is more preferred than others such as in vivo and in vitro due to its low cost and less tedious procedure. The current study was aimed to predict bioactive peptides resulted from the digestion of bovine milk proteins. The digestion or so-called hydrolysis was simulated by means of a web-based in silico method. Identified bovine milk proteins from the available literatures were αS1-casein, αS2-casein, β-casein, κ-casein, β-lactoglobulin, α-lactalbumin, and lactoferrin. The compositions of amino acids (AAs) or protein sequences were accessed and tabulated from the Universal Protein Resource site (UniProt). Furthermore, the hydrolysis of each protein were simulated using three (3) GIS proteases, i.e., pepsin, trypsin, and chymotrypsin, and their possible combinations. All simulations were performed through web-based procedures using PeptideCutter, Expert Protein Analysis System (ExPASy). The resulted peptides were arranged according to the positions of cleavage sites for each cutting simulation, and compared to the available bioactive peptides data base in the literatures in terms of their AA residues (sequences). The simulation results indicated that β-casein and αS1-casein were the most potent proteins to yield bioactive peptides, of 52 and 48%, respectively. Moreover, each type of the investigated bovine milk proteins could be hydrolyzed by GIS proteases to produce antihypertensive bioactive peptides. This web-based in silico method is conclusively useful to predict bioactive peptides derived from bovine milk, and may also be used for other protein sources.

Novel angiotensin-converting enzyme inhibitory peptides from caseins and whey proteins of goat milk

Angiotensin-converting enzyme (ACE) plays a central role in blood pressure regulation by producing the vasoconstrictor angiotensin II. The inhibition of ACE with natural inhibitors, as alternatives to avoid the side effect of synthetic drugs, is a major target in the prevention of hypertension. In this study, we examined the separated caseins and whey proteins of goat milk for the presence of ACE inhibitory peptides. Digestion of isolated whey proteins and caseins of goat milk by gastric pepsin generated soluble hydrolysates exhibiting significant inhibition of ACE compared to weak inhibition by undigested proteins. The hydrolysates were fractionated by size exclusion chromatography, Sephacryl S-100 column, into four fractions (F1–F4). The late-eluting fraction (F4) of either whey or caseins exhibited greater ACE inhibition. Peptides in both F4 fractions, isolated by RP-HPLC, exhibited variable ACE inhibitory activities with the hydrophobic peptide peaks being the most potent ACE inhibitors. MALDI-TOF MS/MS resulted in identification of three potent ACE inhibitory peptides: PEQSLACQCL from β-lactoglobulin (residues 113–122), QSLVYPFTGPI from β-casein (residues 56–66), and ARHPHPHLSFM from κ-casein (residues 96–106). The peptides from whey and caseins exert significant ACE inhibitory activities comparable to that of captopril, an antihypertensive drug, exhibiting IC50 values of 4.45μM and 4.27μM, respectively. The results introduce, for the first time, new potent ACE-inhibitory peptides that can be released by gastric pepsin of goat milk whey and caseins and thus may pave the way for their candidacy as anti-hypertensive bioactive peptides and prevention of associated disorders.

Valorisation of smooth hound (Mustelus mustelus) waste biomass through recovery of functional, antioxidative and antihypertensive bioactive peptides.

Concerns over the environmental and waste disposal problems created by the large amounts of by-products generated from fish processing industries are increasing worldwide. The bioconversion of those marine waste by-products through the enzymatic hydrolysis of their protein content offers the possibility for the development of bioactive peptides for use in various biotechnological applications. The present study aimed to investigate and evaluate the biological and functional properties of smooth hound (Mustelus mustelus) protein hydrolysates (SHPHs) obtained by treatment with intestinal and gastric enzyme preparations from M. mustelus viscera and porcine pancreatin. The results revealed that the SHPHs exhibited different degrees of hydrolysis and antioxidant activity. The hydrolysate produced by the intestinal crude extract presented the highest rate of antioxidative activity, showing an IC50 value of 1.47 ± 0.07 mg/mL in 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assays. The alkaline protease extract from the intestine of M. mustelus produced hydrolysate with the highest angiotensin I-converting enzyme (ACE) inhibitory activity (82 ± 1.52% at 2 mg/mL). All the protein hydrolysates showed excellent solubility and interfacial properties that were governed by pH. The major amino acids detected in SHPHs were glutamic acid/glutamine, aspartic acid/asparagine, histidine and arginine, followed by methionine, phenylalanine, serine, valine and leucine. Overall, the results indicated that smooth hound by-products can be used to generate high value-added products, thus offering a valuable source of bioactive peptides for application in wide range of biotechnological and functional food applications.

Extraction of antioxidative and antihypertensive bioactive peptides from Parkia speciosa seeds

Antioxidative and antihypertensive bioactive peptides were successfully derived from Parkia speciosa seed using alcalase. The effects of temperature (25 and 50°C), substrate-to-enzyme ratio (S/E ratio, 20 and 50), and incubation time (0.5, 1, 2 and 5h) were evaluated based on 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and angiotensin-converting enzyme (ACE) assays. Bioactive peptide extracted at a hydrolysis condition of: temperature=50°C, S/E ratio=50 and incubation time=2h, exhibited the highest DPPH radical scavenging activity (2.9mg GAE/g), reducing power (11.7mM) and %ACE-inhibitory activity (80.2%). The sample was subsequently subjected to fractionation and the peptide fraction of <10kDa showed the strongest bioactivities. A total of 29 peptide sequences from peptide fraction of <10kDa were identified as the most potent contributors to the bioactivities. These novel bioactive peptides were suggested to be beneficial to nutraceutical and food industries.