Chia Seed (Salvia hispanica L.) Pepsin Hydrolysates Inhibit Angiotensin-Converting Enzyme by Interacting with its Catalytic Site

Gastrointestinal digestion of food proteins: Anticancer, antihypertensive, anti-obesity, and immunomodulatory mechanisms of the derived peptides

Food proteins and their peptides play a significant role in the important biological processes and physiological functions of the body. The peptides show diverse biological benefits ranging from anticancer to antihypertensive, anti-obesity, and immunomodulatory, among others. In this review, an overview of food protein digestion in the gastrointestinal tract and the mechanisms involved was presented. As some proteins remain resistant and undigested, the multifarious factors (e.g. protein type and structure, microbial composition, pH levels and redox potential, host factors, etc.) affecting their colonic fermentation, the derived peptides, and amino acids that evade intestinal digestion are thus considered. The section that follows focuses on the mechanisms of the peptides with anticancer, antihypertensive, anti-obesity, and immunomodulatory effects. As further considerations were made, it is concluded that clinical studies targeting a clear understanding of the gastrointestinal stability, bioavailability, and safety of food-based peptides are still warranted.

Bioinformatics tools for the study of bioactive peptides from vegetal sources: evolution and future perspectives

Bioactive peptides from vegetal sources have been shown to have functional properties as anti-inflammatory, antioxidant, antihypertensive or antidiabetic capacity. For this reason, they have been proposed as an interesting and promising alternative to improve human health. In recent years, the numerous advances in the bioinformatics field for in silico prediction have speeded up the discovery of bioactive peptides, also reducing the associated costs when using an integrated approach between the classical and bioinformatics discovery. This review aims to provide an overview of the evolution, limitations and latest advances in the field of bioinformatics and computational tools, and specifically make a critical and comprehensive insight into computational techniques used to study the mechanism of interaction that allows the explanation of plant bioactive peptide functionality. In particular, molecular docking is considered key to explain the different functionalities that have been previously identified. The assumptions to simplify such a high complex environment implies a degree of uncertainty that can only be guaranteed and validated by in vitro or in vivo studies, however, the combination of databases, software and bioinformatics applications with the classical approach has become a promising procedure for the study of bioactive peptides.

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.

The nutritional profile of chia seeds and sprouts: tailoring germination practices for enhancing health benefits-a comprehensive review

Chia seeds have gained significant attention due to their unique composition and potential health benefits, including high dietary fibers, omega-3 fatty acids, proteins, and phenolic compounds. These components contribute to their antioxidant, anti-inflammatory effects, as well as their ability to improve glucose metabolism and dyslipidemia. Germination is recognized as a promising strategy to enhance the nutritional value and bioavailability of chia seeds. Chia seed sprouts have been found to exhibit increased essential amino acid content, elevated levels of dietary fiber and total phenols, and enhanced antioxidant capability. However, there is limited information available concerning the dynamic changes of bioactive compounds during the germination process and the key factors influencing these alterations in biosynthetic pathways. Additionally, the influence of various processing conditions, such as temperature, light exposure, and duration, on the nutritional value of chia seed sprouts requires further investigation. This review aims to provide a comprehensive analysis of the nutritional profile of chia seeds and the dynamic changes that occur during germination. Furthermore, the potential for tailored germination practices to produce chia sprouts with personalized nutrition, targeting specific health needs, is also discussed.

Reference genome of the nutrition-rich orphan crop chia (Salvia hispanica) and its implications for future breeding

Chia (Salvia hispanica L.) is one of the most popular nutrition-rich foods and pseudocereal crops of the family Lamiaceae. Chia seeds are a rich source of proteins, polyunsaturated fatty acids (PUFAs), dietary fibers, and antioxidants. In this study, we present the assembly of the chia reference genome, which spans 303.6 Mb and encodes 48,090 annotated protein-coding genes. Our analysis revealed that ~42% of the chia genome harbors repetitive content, and identified ~3 million single nucleotide polymorphisms (SNPs) and 15,380 simple sequence repeat (SSR) marker sites. By investigating the chia transcriptome, we discovered that ~44% of the genes undergo alternative splicing with a higher frequency of intron retention events. Additionally, we identified chia genes associated with important nutrient content and quality traits, such as the biosynthesis of PUFAs and seed mucilage fiber (dietary fiber) polysaccharides. Notably, this is the first report of in-silico annotation of a plant genome for protein-derived small bioactive peptides (biopeptides) associated with improving human health. To facilitate further research and translational applications of this valuable orphan crop, we have developed the Salvia genomics database (SalviaGDB), accessible at https://salviagdb.org.

Composition, functional properties, health benefits and applications of oilseed proteins: A systematic review

Common oilseeds, such as soybean, peanut, rapeseed, sunflower seed, sesame seed and chia seed, are key sources of edible vegetable oils. Their defatted meals are excellent natural sources of plant proteins that can meet consumers' demand for health and sustainable substitutes for animal proteins. Oilseed proteins and their derived peptides are also associated with many health benefits, including weight loss and reduced risks of diabetes, hypertension, metabolic syndrome and cardiovascular events. This review summarizes the current status of knowledge on the protein and amino acid composition of common oilseeds as well as the functional properties, nutrition, health benefits and food applications of oilseed protein. Currently, oilseeds are widely applied in the food industry regarding for their health benefits and good functional properties. However, most oilseed proteins are incomplete proteins and their functional properties are not promising compared to animal proteins. They are also limited in the food industry due to their off-flavor, allergenic and antinutritional factors. These properties can be improved by protein modification. Therefore, in order to make better use of oilseed proteins, methods for improving their nutrition value, bioactive activity, functional and sensory characteristics, as well as the strategies for reducing their allergenicity were also discussed in this paper. Finally, examples for the application of oilseed proteins in the food industry are presented. Limitations and future perspectives for developing oilseed proteins as food ingredients are also pointed out. This review aims to foster thinking and generate novel ideas for future research. It will also provide novel ideas and broad prospects for the application of oilseeds in the food industry.

Stability and bioactivity of peptides in food matrices based on processing conditions

Bioactive peptides (BPs) generated from food proteins can serve therapeutic purposes against degenerative and cardiovascular diseases such as inflammation, diabetes, and cancer. There are numerous reports on the in vitro, animal, and human studies of BPs, but not as much information on the stability and bioactivity of these peptides when incorporated in food matrices. The effects of heat and non-heat processing of the food products, and storage on the bioactivity of the BPs, are also lacking. To this end, we describe the production of BPs in this review, followed by the food processing conditions that affect their storage bioactivity in the food matrices. As this area of research is open for industrial innovation, we conclude that novel analytical methods targeting the interactions of BPs with other components in food matrices would be greatly significant while elucidating their overall bioactivity before, during and after processing.

Effects of Cold Pressed Chia Seed Oil Intake on Hematological and Biochemical Biomarkers in Both Normal and Hypercholesterolemic Rabbits

Most of the studies on the beneficial effects of chia have been conducted with its seeds. There is less evidence about the effects of cold pressed chia seeds oil on hypercholesterolemia-induced alterations. Thus, this study investigated the effects of cold pressed chia seed oil supplementation on certain hematological and biochemical biomarkers in both normal and hypercholesterolemic rabbits. Thirty two male rabbits were assigned to four different groups and fed on: 1) a regular diet (CD), 2) CD supplemented with 10% chia oil, 3) CD supplemented with 1% cholesterol, 4) CD supplemented with 1% cholesterol and 10% chia oil. After six weeks of dietary interventions, mean arterial blood pressure and visceral fat were measured and blood samples were analyzed for lipid profiles and hematological parameters while erythrocyte membranes and retroperitoneal fat were analyzed for fatty acids composition and biochemical biomarkers. Dietary intervention with chia oil achieved control of the hypercholesterolemia-induced increase of mean arterial blood pressure, neutrophil to lymphocytes ratio, erythrocyte membrane fluidity, and improved erythrocyte morphological alterations. With regard to inflammatory biomarkers, chia oil supplementation reduced omega-6/omega-3 polyunsaturated fatty acids ratios and arachidonic/linolenic fatty acids ratios both in erythrocytes and fat from normal and hypercholesterolemic rabbits. The increase of linolenic fatty acid into the retroperitoneal fat was about 9 times higher than its respective controls. These results provide support for the potential health benefits of chia oil intake on hypercholesterolemia-associated clinical, hematological and biochemical alterations.

Exploration of the Nutritional and Functional Properties of Underutilized Grains as an Alternative Source for the Research of Food-Derived Bioactive Peptides

The estimated increase in world population will lead to a deterioration in global food security, aggravated in developing countries by hidden hunger resulting from protein deficiency. To reduce or avoid this crisis, a dietary shift towards the consumption of sustainable, nutrient-rich, and calorically efficient food products has been recommended by the FAO and WHO. Plant proteins derived from grains and seeds provide nutritionally balanced diets, improve health status, reduce poverty, enhance food security, and contain several functional compounds. In this review, the current evidence on the nutritional and functional properties of underutilized grains is summarized, focusing on their incorporation into functional foods and the role of their proteins as novel source of bioactive peptides with health benefits.

Black Bean (Phaseolus vulgaris L.) Polyphenolic Extract Exerts Antioxidant and Antiaging Potential

Phenolic compounds present in common beans (Phaseolus vulgaris L.) have been reported to possess antimicrobial, anti-inflammatory and ultraviolet radiation (UVR) protective properties. UVR from sunlight, which consists of UV-B and UV-A radiations, induces reactive oxygen species (ROS) and free radical formation, consequently activating proteinases and enzymes such as elastase and tyrosinase, leading to premature skin aging. The objective of this work was to extract, characterize and evaluate the antioxidant and antiaging potential of polyphenols from a black bean endemic variety. The polyphenolic extract was obtained from black beans by supercritical fluid extraction (SFE) using CO₂ with a mixture of water–ethanol as a cosolvent and conventional leaching with a mixture of water–ethanol as solvent. The polyphenolic extracts were purified and characterized, and antioxidant potential, tyrosinase and elastase inhibitory potentials were measured. The extract obtained using the SFE method using CO₂ and H₂O–Ethanol (50:50 v/v) as a cosolvent showed the highest total phenolic compounds yield, with 66.60 ± 7.41 mg GAE/g coat (p > 0.05) and 7.30 ± 0.64 mg C3GE/g coat (p < 0.05) of anthocyanins compared to conventional leaching. Nineteen tentative phenolic compounds were identified in leaching crude extract using ESI-QTOF. Quercetin-3-D-galactoside was identified in crude and purified extracts. The purified SFC extract showed IC₅₀ 0.05 ± 0.002 and IC₅₀ 0.21 ± 0.008 mg/mL for DPPH and ABTS, respectively. The lowest IC₅₀ value of tyrosinase inhibition was 0.143 ± 0.02 mg/mL and 0.005 ± 0.003 mg/mL of elastase inhibition for leaching purified extract. Phenolic compounds presented theoretical free energy values ranging from −5.3 to −7.8 kcal/mol for tyrosinase and −2.5 to −6.8 kcal/mol for elastase in molecular docking (in silico) studies. The results suggest that the purified extracts obtained by SFE or conventional leaching extraction could act as antioxidant and antiaging ingredients for cosmeceutical applications.

Cocoa (Theobroma cacao L.) Seed-Derived Peptides Reduce Blood Pressure by Interacting with the Catalytic Site of the Angiotensin-Converting Enzyme

This study aimed at determining the effect of cocoa proteins (CP) on the blood pressure, using in silico, in vitro and in vivo approaches. The in silico assay showed 26 Criollo cocoa peptides with alignment in the Blast^® analysis. Peptide sequences ranged from 6 to 16 amino acids, with molecular weight ranging from 560.31 to 1548.76 Da. The peptide sequences LSPGGAAV, TSVSGAGGPGAGR, and TLGNPAAAGPF showed the highest theoretical affinity with −8.6, −5.0, and −10.2 kcal/mol, for the angiotensin-converting enzyme (ACE), renin, and angiotensin II type 1 receptor (AT₁-R), respectively. The Criollo CP hydrolysates (CPH) presented in vitro ACE inhibitory activity with an IC₅₀ value of 0.49 mg/mL. Furthermore, the orogastric administration of 150 mg CP/kg/day in rats fed a high-fat (HF) diet (HF + CP group) showed a significant decrease in systolic blood pressure (SBP) by 5% (p < 0.001) and diastolic blood pressure (DBP) by 7% (p < 0.001) compared with the HF group. The human equivalent dose (HED) of CP for an adult (60 kg) is 1.45 g per day. These results suggest that the consumption of CP could reduce blood pressure by blocking ACE, and could be used as an ingredient in the elaboration of antihypertensive functional foods.

Hypotensive peptides derived from plant proteins

Hypertension is a risk factor for arteriosclerosis development and is recognized as a silent killer. Certain processed food materials, digested by protease or through the use of fermentation, have shown exertion of hypotensive effects in human clinical or animal studies, and hypotensive peptides were isolated from them. This review discusses the hypotensive peptides derived from plant proteins, such as grain, soy, vegetables, and seaweeds, and their hypotensive mechanisms. Although angiotensin I-converting enzyme (ACE) inhibition is often noted as one of the mechanisms that may exert antihypertensive effects, ACE inhibitory activity measured by in vitro studies is not associated with the actual hypotensive effect. Thus, this review only highlights the peptide hypotensive effect determined by in vivo studies. This review also discusses the tendency of the amino acid sequence of ACE-inhibitory hypotensive peptides and the possible additional effects of hypotensive peptides independent of ACE inhibition.

Investigation on the characteristics and mechanisms of ACE inhibitory peptides by a thorough analysis of all 8000 tripeptides via binding free energy calculation

Food-derived angiotensin I-converting enzyme (ACE) inhibitory peptides represent a potential source of new antihypertensive. However, their characteristics and binding mechanisms were not well understood. In this study, novel energy calculation and experimentation were combined to elucidate the characteristics and mechanisms of ACE inhibitory tripeptides. ACE inhibitory activity of all 8,000 tripeptides was investigated by in silico experiments. IC50 values of the five top-rated tripeptides ranged from 5.86 to 21.84 μM. Five hundred top-ranked tripeptides were chosen for detailed structure-activity analysis, and a significant preference for aromatic amino acids at both C- and N-terminus was found. By binding free energy analysis of nine representative tripeptides via MM/GBSA, electrostatic energy was found to be the leading energy that contributed to the binding of ACE with its high affinity tripeptides. Besides, S355, V380, and V518, three residues positioned around the classical binding pockets of ACE, also played a key role in ACE's binding. Therefore, for tripeptides, their binding pockets in ACE were redefined. In conclusion, the characteristics of ACE inhibitory peptides were more deeply illustrated by the thorough analysis of all tripeptides. The energy analysis allows a better understanding of the binding mechanisms of ACE inhibitory peptides, which could be used to redesign the ACE inhibitors for stronger inhibitory activity.

Investigation of Chlorella pyrenoidosa Protein as a Source of Novel Angiotensin I-Converting Enzyme (ACE) and Dipeptidyl Peptidase-IV (DPP-IV) Inhibitory Peptides

Chlorella pyrenoidosa (C. pyrenoidosa) is a microalgae species with a remarkably high protein content that may potentially become a source of hypotensive and hypoglycemic peptides. In this study, C. pyrenoidosa proteins were extracted and hydrolyzed overnight with pepsin and trypsin with final degrees of hydrolysis of 18.7% and 35.5%, respectively. By LC-MS/MS, 47 valid peptides were identified in the peptic hydrolysate (CP) and 66 in the tryptic one (CT). At the concentration of 1.0 mg/mL, CP and CT hydrolysates inhibit in vitro the angiotensin-converting enzyme (ACE) activity by 84.2 ± 0.37% and 78.6 ± 1.7%, respectively, whereas, tested at cellular level at the concentration of 5.0 mg/mL, they reduce the ACE activity by 61.5 ± 7.7% and 69.9 ± 0.8%, respectively. At the concentration of 5.0 mg/mL, they decrease in vitro the DPP-IV activity by 63.7% and 69.6% and in Caco-2 cells by 38.4% and 42.5%, respectively. Short peptides (≤10 amino acids) were selected for investigating the potential interaction with ACE and DPP-IV by using molecular modeling approaches and four peptides were predicted to block both enzymes. Finally, the stability of these peptides was investigated against gastrointestinal digestion.

Recently isolated food-derived antihypertensive hydrolysates and peptides: A review

Hypertension is a non-communicable disease characterized by elevated blood pressure, and a prominent metabolic syndrome of modern age. Food-borne bioactive peptides have shown considerable potencies as suitable therapeutic agents for hypertension. The peptide inhibition of the angiotensin I-converting enzyme (ACE) from its default biochemical conversion of Ang I to Ang II has been studied and more relatively adopted in several studies. This review offers an examination of the isolation of concomitant proteins in foods, their hydrolysis into peptides and the biofunctionality checks of those peptides based on their anti-hypertensive potentialities. Furthermore, critical but concise details about methodologies and analytical techniques used in the purification of such peptides are discussed. This review is a beneficial literature supplement for scholars and provides functional awareness material for the food-aligned alternative therapy for hypertension. In addition, it points researchers in the direction of adopting food materials and associated by-products as natural sources for the isolation biologically active peptides.

Spectroscopic and molecular docking studies on the interaction of phycocyanobilin with peptide moieties of C-phycocyanin

The binding of C-phycocyanin (CPC), a light harvesting pigment with phycocyanobilin (PCB), a chromophore is instrumental for the coloration and bioactivity. In this study, structure-mediated color changes of CPC from Spirulina platensis during various enzymatic hydrolysis was investigated based on UV-visible, circular dichroism, infra-red, fluorescence, mass spectrometry, and molecular docking. CPC was hydrolyzed using 7.09 U/mg protein of each enzyme at their optimal hydrolytic conditions for 3 h as follows: papain (pH 6.6, 60 °C), dispase (pH 6.6, 50 °C), and trypsin (pH 7.8, 37 °C). The degree of hydrolysis was in the order of papain (28.4%) > dispase (20.8%) > trypsin (7.3%). The sequence of color degradation rate and total color difference (ΔE) are dispase (82.9% and 40.37), papain (72.4% and 24.70), and trypsin (58.7% and 25.43). The hydrolyzed peptides were of diverse sequence length ranging from 8 to 9 residues (papain), 7-12 residues (dispase), and 9-63 residues (trypsin). Molecular docking studies showed that key amino acid residues in the peptides interacting with chromophore. Amino acid residues such as Arg86, Asp87, Tyr97, Asp152, Phe164, Ala167, and Val171 are crucial in hydrogen bonding interaction. These results indicate that the color properties of CPC might associate with chromopeptide sequences and their non-covalent interactions.

Exploring a New Natural Treating Agent for Primary Hypertension: Recent Findings and Forthcoming Perspectives

Primary hypertension describes abnormally-high systolic/diastolic blood pressure in a resting condition caused by various genetic or environmental risk factors. Remarkably, severe complications, such as ischemic cardiovascular disease, stroke, and chronic renal disease have led to primary hypertension becoming a huge burden for almost one-third of the total population. Medication is the major regimen for treating primary hypertension; however, recent medications may have adverse effects that attenuate energy levels. Hence, the search for new hypotensive agents from folk or traditional medicine may be fruitful in the discovery and development of new drugs. This review assembles recent findings for natural antihypertensive agents, extracts, or decoctions published in PubMed, and provides insights into the search for new hypotensive compounds based on blood-pressure regulating mechanisms, including the renin-angiotensin-aldosterone system and the sympathetic/adrenergic receptor/calcium channel system.