Antihypertensive effect and antioxidant activity of peptide fractions extracted from Spanish dry-cured ham

Insight into the autochthonous bacterial strains as starter cultures for improving the flavor profiles of dry-cured duck: Changes in microbial diversity and metabolic profiles

The purpose of this study was to reveal the effect of inoculating autochthonous bacterial strains (Lactobacillus and Staphylococcus simulans) on the flavor profiles, microbial community, and metabolites, and to elucidate the potential mechanism of flavor formation in dry-cured duck. The results indicated that the inoculation of bacterial strains could improve the amount of lactic acid bacteria and Staphylococcus and reduce the counts of Enterobacteria. There was a significant difference in flavor profiles between samples inoculated with different strains. Hexanal-D, acetone, 3-methyl-1-butanol-D, thiophene, hexanal-M, propanal, pentanal, (Z)-2-penten-1-ol and ethanol-D were the potential biomarkers. A total of 70 differential metabolites were screened and identified. Amino acid metabolism and lipid metabolism were the key pathways for the production of flavor and metabolites in dry-cured duck. The results of this study will improve our understanding of the mechanism of flavor formation regarding the inoculation of autochthonous starter cultures.

Influence of Pig Genetic Line and Salt Reduction on Peptide Production and Bioactivity of Dry-Cured Hams

Ham (Jamón) is a product of great value in Spanish gastronomy, although experts have recommended reducing its consumption due to its high salt content and its relationship with cardio-vascular diseases due to the increase in blood pressure it may cause. Therefore, the objective of this study was to evaluate how the reduction of salt content and the pig genetic line influence bioactivity in boneless hams. For this purpose, 54 hams were studied, 18 boneless Iberian hams (RIB), 18 boneless white hams from commercial cross-bred pigs (RWC), and 18 salted and traditionally processed Iberian hams (TIB) to check if the pig genetic line (RIB vs. RWC) or the processing (RIB vs. TIB) affect the peptide production and bioactivity of the hams. The pig genetic line significantly affected the activity of ACE-I and DPPH, with RWC having the highest ACE-I activity and RIB having the highest antioxidative activity. This coincides with the results obtained in the identification of the peptides and the bioactivity analysis performed. Salt reduction positively affected the different hams, influencing their proteolysis and increasing their bioactivity in traditionally cured hams.

Antioxidant and angiotensin-I-converting enzyme (ACE-I) inhibitory activities of protein hydrolysates derived from water buffalo (Bubalus bubalis) liver

In the current study, we attempted to use ginger as a novel and natural source of protease in comparison with other commercially available enzymes to extract and characterize antioxidant and antihypertensive hydrolysates from water buffalo liver, a protein rich offal. Hydrolysis of protein extracts from buffalo liver using proteinase-K, pronase-E and ginger protease significantly increased the %degree of hydrolysis (18.5-55%) and generated low-molecular weight peptides evident from SDS-PAGE. Enzyme treated hydrolysates exhibited higher (p < 0.05) DPPH radical scavenging activity (43.7-82.4%) and angiotensin-I-converting enzyme (ACE-I) inhibitory activity (46.9-50.1%) relative to control. Mass spectrometric analysis (MALDI-TOF MS) of selected gel-filtered fractions identified few important peptides derived from nuclear ribonucleoprotein, pyruvate kinase and phosphoglycerate kinase that possess strong antioxidant activity. Present findings indicate the efficacy of partially purified ginger as a novel source of protease in generating protein hydrolysates from water buffalo liver with significant antioxidant and antihypertensive activity in vitro. We successfully demonstrated the recovery of functional bioactive peptides from water buffalo liver which presents a potential opportunity for the meat industries to economically use this important byproduct.

Formation and inhibition mechanism of novel angiotensin I converting enzyme inhibitory peptides from Chouguiyu

Angiotensin I converting enzyme (ACE) inhibitory peptides from fermented foods exhibit great potential to alleviate hypertension. In this study, the peptide extract from Chouguiyu exhibited a good inhibition effect on ACE, and the inhibition rate was significantly enhanced after fermentation for 8 days. The ACE inhibitory peptides were further identified, followed by their inhibition and formation mechanisms using microbiome technology and molecular docking. A total of 356 ACE inhibitory peptides were predicted using in silico, and most ACE inhibitory peptides increased after fermentation. These peptides could be hydrolyzed from 94 kinds of precursor proteins, mainly including muscle-type creatine kinase, nebulin, and troponin I. P1 (VEIINARA), P2 (FAVMVKG), P4 (EITWSDDKK), P7 (DFDDIQK), P8 (IGDDPKF), P9 (INDDPKIL), and P10 (GVDNPGHPFI) were selected as the core ACE inhibitory peptides according to their abundance and docking energy. The salt bridge and conventional hydrogen bond connecting unsaturated oxygen atoms in the peptides contributed most to the ACE inhibition. The cleavage proteases from the microbial genera in Chouguiyu for preparing these 7 core ACE inhibitory peptides were further analyzed by hydrolysis prediction and Pearson's correlation. The correlation network showed that P7, P8, and P9 were mainly produced by the proteases from LAB including Lactococcus, Enterococcus, Vagococcus, Peptostreptococcus, and Streptococcus, while P1, P2, P4, and P10 were mainly Produced by Aeromonas, Bacillus, Escherichia, and Psychrobacter. This study is helpful in isolating the proteases and microbial strains to directionally produce the responding ACE inhibitory peptides.

Peptidomic Characteristic of Peptides Generated in Dry-Cured Loins with Probiotic Strains of LAB during 360-Days Aging

Peptidomics refers to the comprehensive profiling of endogenous peptides obtained from biological sources. The formation of endogenous peptides is dependent on not only endogenous factors but also exogenous factors such as microbial proteases or process conditions, including fermentation. This study analyzed the probiotic strains of Lactobacillus rhamnosus LOCK900 (LOCK), Bifidobacterium animalis ssp. lactis BB-12 (BB12), and potential probiotic Lactobacillus acidophilus Bauer Ł0938 (BAUER) to assess their ability of fermentation and peptide production in dry-cured pork loin. The peptides obtained after in vitro digestion were characterized by liquid chromatography–tandem mass spectrometry. Based on the sequences identified, the degree of similarity or differences between the peptides was determined and presented graphically on the factor plane. The charts showed that the meat products aged for 180 and 270 days were the most diverse when BB12 or BAUER were used as starter cultures. Myosin and keratin were identified as the most likely precursors of bioactive peptides in products obtained using this strain of lactic acid bacteria (LAB). The knowledge acquired from this study may contribute to the design of functional meat products as the results revealed not only the peptidogenic potential of the LAB strains indicated on their beneficial effect on the bioactivity of peptides.

The oxidation status of three types of duck meat (conventional, organic, wild) during refrigerated storage under air and vacuum-packaged atmospheres

1. This study evaluated and compared the oxidation status of meat from conventionally-farmed, organic and wild ducks during chilled storage in air or vacuum packaging. In total, 48 carcasses from each group of ducks were investigated, and 24 carcasses from each type of duck were stored under vacuum or in air at 3°C±1°C. Sample analyses were conducted after 1, 3, 6 and 9 days of storage.2. The antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl: DPPH), thiobarbituric acid reactive substances (TBARS) and free fatty acids in the breast, thigh and wing muscles were determined.3. The antioxidant capacity of meat from conventional ducks was higher than that from organic and wild ducks. The muscles of organic and wild ducks were more susceptible to secondary oxidation (particularly when stored in air) than conventionally-raised birds. The free fatty acid levels in samples of breast and thigh meat from wild ducks on the last day of storage were higher than in conventional and organic ducks.4. The results showed that the oxidation status of meat from conventional ducks was more stable during refrigerated storage than the meat of organic and wild ducks.

Beneficial Impact of Pork Dry-Cured Ham Consumption on Blood Pressure and Cardiometabolic Markers in Individuals with Cardiovascular Risk

Background: Evidence suggests that bioactive peptides reduce hypertension and affect certain metabolic pathways. Methods: Fifty-four volunteers with stage 1 prehypertension and/or hypercholesterolemia and/or basal glucose >100 mg/dL were recruited and randomized to pork dry-cured ham (n = 35) or cooked ham (placebo group; n = 19) for 28 days. After a wash-out period, meat products were changed for 28 additional days. Bioactive peptides composition and enzyme inhibitory activities of both products were characterized. Treatment comparisons for the main effects were made using a two (treatment) × two (times) repeated measures minus the effect of cooked ham (placebo). Results: 24 h mean systolic and diastolic pressures decreased up to 2.4 mmHg in the dry-cured ham period (treatment effect, p = 0.0382 y p = 0.0233, respectively) as well as the number of systolic pressure measures > 135 mmHg (treatment effect, p = 0.0070). Total cholesterol levels also decreased significantly after dry-cured ham intake (p = 0.049). No significant differences were observed between the two treatments for basal glucose, HOMA-IR index and insulin levels (p > 0.05). However, a significant rise of ghrelin levels was observed (treatment effect, p = 0.0350), while leptin plasma values slightly decreased (treatment effect, p = 0.0628). Conclusions: This study suggested the beneficial effects of regular dry-cured ham consumption on the improvement of systolic/diastolic blood pressures and facilitated the maintenance of metabolic pathways, which may be beneficial in the primary prevention of cardiovascular disease.

Peptidomic analysis of digested products of surimi gels with different degrees of cross-linking: In vitro gastrointestinal digestion and absorption

To investigate the cross-linking degree on the in vitro gastrointestinal digestion and absorption properties of surimi gel, three types of surimi gels with low, moderate, and high cross-linking degrees were prepared, and then in vitro digestion models (static and dynamic) and a Caco-2 cell monolayer model combined with LC-MS/MS were used to do peptidomic analysis of digestive and absorbed juices. The results showed that an increase in cross-linking degree promoted the release of peptides after gastrointestinal digestion. These peptides originated from the myosin head and rod, the rod was the main digestion region. More potential bioactive peptides from intestinal digestive juice could be transported through the intestinal epithelium. Compared with static digestion, dynamic digestion digested surimi gels more thoroughly, especially during gastric digestion. This study provides a theoretical basis and guidance for the production of surimi products with higher nutritional value and the in vitro digestion methods of gelatinous foods.

Preparation, characterization, and gel characteristics of nanoemulsions stabilized with dextran-conjugated clam Meretrix meretrix linnaeus protein isolate

In this study, the stability and flavor characteristics of nanoemulsions prepared with dextran-conjugated Meretrix meretrix clam protein isolate were studied by characterizing particle size, polydispersity index, zeta potential, turbidity, microstructure, e-tongue, e-nose and HS-GC-IMS. Compared with the N_CPI (CPI nanoemulsions) and N_{CPI-Dex Mix} (CPI-Dex Mix nanoemulsions), the N_{CPI-Dex Con} (CPI-Dex Con nanoemulsions) has better stability and flavor. The breaking strength and breaking strain of clam sausages were significantly (P > 0.05) affected by the addition of N_{CPI-Dex Con}. The gel strength with 8% N_{CPI-Dex Con} was the highest (5122.08 g‧mm), a 51.07% increase compared with the control group (3390.58 g‧mm). The clam sausages supplemented with the 8% N_{CPI-Dex Con} had the highest sensory score, with the densest and the most uniform gel structure. Therefore, CPI-Dex Con stabilized nanoemulsions could effectively improve the gel property and flavor of the clam sausages.

Inhibition of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase enzyme by dipeptides identified in dry-cured ham

High cholesterolemia is a key risk factor for the development of cardiovascular diseases, which are the main cause of mortality in developed countries. Most therapies are focused on the modulation of its biosynthesis through 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoAR) inhibitors. In this sense, food-derived bioactive peptides might act as promising health alternatives through their ability to interact with crucial enzymes involved in metabolic pathways, avoiding the adverse effects of synthetic drugs. Dry-cured ham has been widely described as an important source of naturally-generated bioactive peptides exerting ACEI-inhibitory activity, antioxidant activity, and anti-inflammatory activity between others. Based on these findings, the aim of this work was to assess, for the first time, the in vitro inhibitory activity of HMG-CoAR exerted by dipeptides generated during the manufacturing of dry-cured ham, previously described with relevant roles on other bioactivities.

The in vitro inhibitory activity of the dipeptides was assessed by measuring the substrate consumption rate of the 3-hydroxy-3-methylglutaryl CoA reductase in their presence, with the following pertinent calculations.

Further research was carried out to estimate the possible interactions of the most bioactive dipeptides with the enzyme by performing in silico analysis consisting of molecular docking approaches.

Main findings showed DA, DD, EE, ES, and LL dipeptides as main HMG-CoAR inhibitors. Additionally, computational analysis indicated statin-like interactions of the dipeptides with HMG-CoAR.

This study reveals, for the first time, the hypocholesterolemic potential of dry-cured ham-derived dipeptides and, at the same time, converges in the same vein as many reports that experimentally argue the cardiovascular benefits of dry-cured ham consumption due to its bioactive peptide content.

Bioactivities generated from meat proteins by enzymatic hydrolysis and the Maillard reaction

Bioactive peptides are released from meat proteins by enzymatic hydrolysis (i.e., gastrointestinal digestion, aging/storage, fermentation, and protease treatment). Such peptides attribute physiological functions to meat and meat products and are promising food ingredients for developing functional foods. Meat by-products (e.g., blood and collagen) are also good sources for generating bioactive peptides, since they are produced in large quantities and are rich in proteins. Although protein-derived bioactive peptides are attractive ingredients, their changes by the Maillard reaction during processing, cooking, and storage should be investigated. This article briefly reviews the production of bioactive peptides from meat and meat by-products. Such diverse peptides affects circulatory, nervous, alimentary, and immune systems. Then, the bioactivities of Maillard reaction products (MRPs) generated from protein hydrolysates are discussed. Special attention is paid to bioactivities of 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) inhalation. As such activities, we have evaluated the impact of DMHF on blood pressure, moods, brainwaves, and dietary intake. Our efforts for understanding various aspects and implication of peptides and MRPs from meat proteins would open new avenues in the meat and food industry.

A Review on Health-Promoting, Biological, and Functional Aspects of Bioactive Peptides in Food Applications

Food-derived bioactive peptides are being used as important functional ingredients for health-promoting foods and nutraceuticals in recent times in order to prevent and manage several diseases thanks to their biological activities. Bioactive peptides are specific protein fractions, which show broad applications in cosmetics, food additives, nutraceuticals, and pharmaceuticals as antimicrobial, antioxidant, antithrombotic, and angiotensin-I-converting enzyme (ACE)-inhibitory ingredients. These peptides can preserve consumer health by retarding chronic diseases owing to modulation or improvement of the physiological functions of human body. They can also affect functional characteristics of different foods such as dairy products, fermented beverages, and plant and marine proteins. This manuscript reviews different aspects of bioactive peptides concerning their biological (antihypertensive, antioxidative, antiobesity, and hypocholesterolemic) and functional (water holding capacity, solubility, emulsifying, and foaming) properties. Moreover, the properties of several bioactive peptides extracted from different foods as potential ingredients to formulate health promoting foods are described. Thus, multifunctional properties of bioactive peptides provide the possibility to formulate or develop novel healthy food products.

Sodium reformulation and its impact on oxidative stability and sensory quality of dry-cured rabbit legs

The aim of this study was to evaluate the oxidative stability and sensory quality of dry-cured rabbit legs produced with a reduction or replacement of 50% of NaCl by KCl and with the addition of monosodium glutamate (MG). Oxidative stability was evaluated during 90 days of storage at 20 °C by determining pH, redox potential (Eh), and TBARS while overall liking and sensory profile were measured at the beginning of storage. The results indicated that oxidative stability of the dry-cured rabbit legs was not affected by the sodium reformulation. However, TBARS values increased about 15-fold during storage in all treatments. Dry-cured rabbit legs produced with KCl showed lower scores (P < 0.05) for the overall liking and flavor attributes as "astringent flavor", "bitter taste" and "metallic flavor". The addition of MG to products with 50% NaCl reduction provided a liking and a sensory profile similar to the product with 100% NaCl.

Functional characterisation and sensory evaluation of a novel synbiotic okara beverage

This study aimed to produce four different beverages from okara (soybean by-product) previously hydrolyzed by Cynara cardunculus enzymes and fermented by probiotic bacteria or unfermented beverage. The probiotic viable cells, the isoflavones profile and organic acids were evaluated in the okara beverage. In addition, total phenolic content, antioxidant and ACE inhibitory activities were evaluated at storage time and during in vitro gastrointestinal digestion of all beverages. The probiotic was viable throughout storage in all fermented beverages. The significant bioconversion of the isoflavone glycosides into their corresponding bioactive aglycones was observed in fermented beverage. Furthermore, the beverages showed a good ACE inhibitory activity. After gastrointestinal tract, all beverages showed an increase in the antioxidant and ACE inhibitory activities. In conclusion, this study shows that the application of okara for a multifunctional beverage could be a promising strategy in the disease prevention and contribution to a zero waste approach in food industry.

Isolation and identification of bioactive peptides from Xuanwei ham that rescue oxidative stress damage induced by alcohol in HHL-5 hepatocytes

Peptides extracted from Xuanwei ham (XHP) can prevent free radical-induced diseases. The aim of the present study was to isolate and identify bioactive peptides from Xuanwei hams that rescue the oxidative stress damage induced by alcohol in HHL-5 hepatocytes. Alcohol-treated HHL-5 human hepatocytes were utilized as the alcohol-induced hepatocyte damage model to evaluate the effects of XHP on amounts of aminotransferase (ALT), aspartate aminotransferase (AST) and malondialdehyde (MDA). The result showed that XHP could significantly reduce ALT, AST and MDA, the major biomarkers of liver damage. The crude XHP was separated by size exclusion chromatography, followed by the evaluation of respective activities. Then, the most active components were further separated by RP-HPLC, and their activities were evaluated according to the above method. The peptide was identified as a hexapeptide with the sequence of Asn-Pro-Pro-Lys-Phe-Asp (NPPKFD) through LC-MS/MS. Further, the molecular mechanisms by which NPPKFD prevents alcohol-induced oxidative stress damage were revealed. Results showed that the hexapeptide could downregulate CYP2E1 expression, reduce generation of ROS and enhance oxidant defense systems via the activation of NrF2/HO-1 pathway. The findings suggest that Xuanwei ham can be used as a new source of bioactive peptides for protection from alcohol-induced liver damage.

Advances on Food-Derived Peptidic Antioxidants-A Review

The oxidation process is considered to be the main reason behind human aging, human degenerative diseases and food quality degradation. Food-derived peptidic antioxidants (PAs) have wide sources and great activity, and have broad application prospects in removing excess reactive oxygen species in the body, anti-aging and preventing and treating diseases related to oxidative stress. On the other hand, PAs are expected to inhibit the lipid peroxidation of foods and increase the stability of the food system in the food industry. However, the production pathways and action mechanism of food-derived PAs are diverse, which makes it is difficult to evaluate the performance of PAs which is why the commercial application of PAs is still in its infancy. This article focuses on reviewing the preparation, purification, and characterization methods of food-derived PAs, and expounds the latest progress in performance evaluation and potential applications, in order to provide an effective reference for subsequent related research of PAs.

Pork frankfurters prepared with hydrolyzed whey: Preliminary product quality aspects and inhibitory activity of the resulting peptides on angiotensin-converting enzyme

The objective of this study was to assess the addition of whey protein hydrolysate (WH) on quality and antihypertensive potential of pork frankfurters, as the first step in development of a functional meat product. A hydrolyzed whey protein solution was incorporated in the frankfurter formula according to the following treatments: T0 (30% water), T1 (10% WH, 20% water), T2 (20% WH, 10% water) and T3 (30% WH). Addition of up to 30% WH increased lightness and yellowness, decreased hardness and chewiness by 15% and shear force by 43%, with no effect on pH (6.36) and cooking yield (93%). The WH addition resulted in an increase in the antihypertensive potential (IC₅₀ 258.78 μg/mL) relative to the T0 (IC₅₀ 1548.25 μg/mL). Cold storage of the product with 30% WH did not impact physicochemical quality, nor did it modify the antihypertensive potential. Incorporation of whey hydrolysate into pork frankfurters could be an option for providing antihypertensive peptides in food for health-oriented consumers.

Antihypertensive Effects in Vitro and in Vivo of Novel Angiotensin-Converting Enzyme Inhibitory Peptides from Bovine Bone Gelatin Hydrolysate

In this study, we investigated the antihypertensive effects in vitro and in vivo of novel angiotensin-converting enzyme inhibitory (ACEI) peptides purified and identified from bovine bone gelatin hydrolysate (BGH). Thirteen ACEI peptides were identified from BGH, and among which, RGL-(Hyp)-GL and RGM-(Hyp)-GF exhibited high ACE inhibition with IC₅₀ values of 1.44 and 10.23 μM. Molecular docking predicted that RGM-(Hyp)-GF and ACE residues of Glu384, His513, and Lys511 formed hydrogen-bonding interactions at distances of 2.57, 2.99, and 2.42 + 3.0 Å. RGL-(Hyp)-GL formed hydrogen bonds with Lys511 and Tyr523 and generated hydrogen-bonding interactions with His387 and Glu411 in the zinc(II) complexation motif at distances of 2.74 and 3.03 + 1.93 Å. The maximal decrements in systolic blood pressure in spontaneously hypertensive rats induced by one-time gavage of RGL-(Hyp)-GL and RGM-(Hyp)-GF at 30 mg/kg were 31.3 and 38.6 mmHg. RGL-(Hyp)-GL had higher enzyme degradation resistance than that of RGM-(Hyp)-GF in vitro incubation in rat plasma, and they were sequentially degraded into pentapeptides and tetrapeptides within 2 h. Our results indicate that BGH can serve as a nutritional candidate to control blood pressure.

Multifunctional Peptides from Spanish Dry-Cured Pork Ham: Endothelial Responses and Molecular Modeling Studies

Food peptides contain a very wide range of diversified structures, which explains their diverse range of functional activities. Proatherogenic endothelium is related to vasoconstriction, inflammation, and oxidative stress. In this line, four synthetic bioactive peptides from dry-cured pork ham, previously identified according to their Angiotensin I Converting Enzyme (ACE) inhibitory capacity and high bioavailability, were tested. Among them, KPVAAP displayed an estimated IC₅₀ of 59.22 µM for human ACE inhibition, and docking simulations demonstrated the consistency of the noncompetitive binding with the protein. The addition of synthetic peptides to human endothelial cells significantly prevents the expression of genes related to endothelial dysfunction and inflammation (eNOS, ICAM-1, VCAM-1, IL-6) and lowers NF-κB activation (all p < 0.05). In silico dockings showed that the four bioactive peptides interact with the regulatory subunit NEMO of the NF-κB transcription factor at the same site as other characterized inhibitors (CC2-LZ region). This is the first study linking experimental and computational approaches that shows NF-κB to be the target of biopeptides of food origin. These multifunctional peptides from dry-cured pork ham make them good candidates for further research into their therapeutic or preventive use to attenuate the inflammatory atherosclerotic process.

Characteristics of Selected Antioxidative and Bioactive Compounds in Meat and Animal Origin Products

Meat and meat products have a high nutritional value. Besides major components, meat is rich in bioactive components, primarily taurine, l-carnitine, choline, alpha-lipoic acid, conjugated linoleic acid, glutathione, creatine, coenzyme Q10 and bioactive peptides. Many studies have reported their antioxidant and health-promoting properties connected with their lipid-lowering, antihypertensive, anti-inflammatory, immunomodulatory activity and protecting the organism against oxidative stress. The antioxidant activity of meat components results, among others, from the capability of scavenging reactive oxygen and nitrogen species, forming complexes with metal ions and protecting cells against damage. This review is focused to gather accurate information about meat components with antioxidant and biological activity.

Lipid Nanoparticles-Encapsulated YF4: A Potential Therapeutic Oral Peptide Delivery System for Hypertension Treatment

Drugs are administered orally in the clinical treatment of hypertension. Antihypertensive peptides have excellent angiotensin converting enzyme inhibitors activity in vitro. However, the poor oral bioavailability and therapeutic effect of antihypertensive peptides were mainly caused by rapid degradation in gastrointestinal and the short circulation time in blood, which remain to be further optimized. Therefore, the novel oral peptide delivery system is urged to improve the oral absorption and efficacy of peptide drugs. In this work, Tyr-Gly-Leu-Phe (YF4)-loaded lipid nanoparticles (YF4-LNPs) combined the advantages of polymer nanoparticles and liposomes were developed, which could greatly enhance the oral bioavailability and ameliorate the sustained release of peptide drug. YF4 loaded nanoparticles (YF4-NPs) were firstly prepared by a double-emulsion internal phase/organic phase/external phase (W1/O/W2) solvent evaporation method. YF4-NPs were further coated by membrane hydration-ultrasonic dispersion method to obtain the YF4-LNPs. The optimal YF4-LNPs showed a small particle size of 227.3 ± 3.8 nm, zeta potential of -7.27 ± 0.85 mV and high entrapment efficiency of 90.28 ± 1.23%. Transmission electronic microscopy analysis showed that the core-shell lipid nanoparticles were spherical shapes with an apparent lipid bilayer on the surface. Differential scanning calorimetry further proved that YF4 was successfully entrapped into YF4-LNPs. The optimal preparation of YF4-LNPs exhibited sustained release of YF4 in vitro and a 5 days long-term antihypertensive effect in vivo. In summary, the lipid nanoparticles for oral antihypertensive peptide delivery were successfully constructed, which might have a promising future for hypertension treatment.

Physicochemical and sensory characteristics of dry-cured loin made from pigs fed Allium hookeri added whey powder and sensory trait evaluation using electronic tongue

The aim of this study was to determine the effect of dietary supplementation with Allium hookeri (A. hookeri) added whey powder on the physicochemical characteristics of dry-cured loin (CON, basal diet; AH, addition of 1% A. hookeri; AHW, addition of 0.5% A. hookeri and 4% whey powder) during manufacturing (pre- and post-salting, drying and ripening process) and analyse their sensory characteristics using electronic tongue. Crude fat and weight yield of AH were higher (P &lt; 0.05) than those of CON. The AH inhibited (P &lt; 0.05) lipid oxidation and the reduction of redness during manufacturing. The percentage of some free amino acids (tyrosine, methionine, phenylalanine, isoleucine and leucine) in AHW was higher (P &lt; 0.05) compared with those in CON. Monounsaturated fatty acid composition was the highest (P &lt; 0.05) in AHW. Sensory evaluation by panellists did not show significant differences among the three groups (CON, AH and AHW). However, the richness of AH and AHW was significantly higher compared with that of CON based on electronic tongue analysis. Taken together, these results revealed that AH supplementation with whey powder had higher oxidative stability and enhanced dry-cured loin quality.

Anti-proliferative Effect of a Novel Anti-oxidative Peptide in Hanwoo Beef on Human Colorectal Carcinoma Cells

The present study aimed to characterise anti-oxidant peptides from water-soluble protein extracts of Hanwoo beef and evaluate their anti-proliferative effect on human colorectal carcinoma cells (HCT116). Antioxidant peptides were purified from the low-molecular-weight fraction (<3 kDa) of Hanwoo beef extract. Antioxidant activity of peptide fractions was determined using the oxygen radical absorbance capacity (ORAC) assay. Purified peptide (P3) displayed higher ORAC activity than the low-molecular-weight fraction (202.66 μM TE/g vs 167.38 μM TE/g of dry matter, respectively) (p<0.05). The peptide sequence of P3 was Cys-Cys-Cys-Cys-Ser-Val-Gln-Lys (888.30 Da). The novel peptide P3, at 250 μg/mL, also significantly inhibited HCT116 cell proliferation up to 25.24% through phosphorylation of ERK, JNK, and p38 kinase (p<0.05). Hence, antioxidant peptide P3 from Hanwoo beef extract can be used as an antioxidative and anti-cancer agent in the functional food industry.

Effect of moderate and regular consumption of Cinco Jotas acorn-fed 100% Iberian ham on overall cardiovascular risk: A cohort study

OBJECTIVE

To evaluate the impact that the moderate and regular consumption of Cinco Jotas acorn-fed 100% Iberian ham has on overall cardiovascular risk, lipid parameters, blood pressure, and weight.

METHODS

A longitudinal, analytical, and quasi-experimental clinical study with repeated measures was carried out with 100 randomly selected individuals in primary care. The sample population included men and women (64%) between the ages of 25 and 55 (42.08, SD 9.6) who were not diagnosed with any cardiovascular illness or diabetes, were not undergoing antihypertensive treatment, nor taking lipid-lowering drugs. There were four visits during a 2-week washout period for the first of three phases. Phases 2 and 3 included an 8-week habitual diet phase followed by an 8-week intervention phase when participants consumed 40 g daily of acorn-fed 100% Cinco Jotas Iberian ham. Measurements of cardiovascular risk factors were taken following the SCORE table. These included total cholesterol, high-density lipoproteins cholesterol (HDL-c), low-density lipoproteins cholesterol (LDL-c), triglycerides (TG), and weight.

RESULTS

The average vascular risk (SCORE) was 0.20 (SD 0.49) before the consumption phase and 0.18 (SD 0.48) at the end of the study (p > 0.05). An increase in HDL-c of 5 mg/dl was observed while there was a decrease in LDL-c and TG of 10 mg/dl (p < 0.05). There were no differences in total cholesterol levels, blood pressure, or weight; nor were differences observed in average consumption of calories, protein, lipids, carbohydrates, or alcohol (p > 0.05).

CONCLUSIONS

The daily consumption of 40 g of Cinco Jotas acorn-fed 100% Iberian ham does not increase the risk of cardiovascular disease and has a favorable impact on lipid levels without affecting blood pressure or weight.

The influence of acid whey on the antioxidant peptides generated to reduce oxidation and improve colour stability in uncured roast beef

BACKGROUND

The effect of marinating beef in acid whey on the antioxidant peptides generated, and their influence on lipid oxidation, colour stability, sensory analysis and protein degradation products in uncured roasted beef stored 6 weeks in vacuum conditions (T = 4 °C) were determined. Measurements of pHe, water activity, oxidation-reduction potential, colour, TBARS, the cutting force, texture and amino acid profile, the total content of peptides, and antioxidant activity of isolated peptides were conducted immediately after production and during 42 days of storage.

RESULTS

The non-nitrite control batch (C) was characterized by a lower a* value (6.33-6.70) during the whole storage period compared to the non-nitrite sample with acid whey (W). It also appears that meat with the worst colour stability has the poorest oxidative stability (C = 1.57 mg MDA kg^-1 , W = 0.76 mg MDA kg^-1 ). Activity against reactive forms of oxygen to fraction A and fraction B (P < 0.05) showed an increasing trend with time and it was the largest in sample C and W.

CONCLUSION

The results indicated that bioactive peptides could be generated in uncured roasted beef. The <3.5 kDa peptides have strong antioxidant activity, as a result of which they function as inhibitors of lipid oxidation and colour discoloration during prolonged storage. © 2018 Society of Chemical Industry.

Peptidomic analysis of antioxidant and ACE-inhibitory peptides obtained from tomato waste proteins fermented using Bacillus subtilis

In this study, tomato seeds were obtained as by-products and submitted to fermentation with the proteolytic strain Bacillus subtilis A14h. The resulting peptide mixture was fractionated and purified through different chromatographic steps. Fractions were assayed for antioxidant and angiotensin converting enzyme (ACE)-inhibitory activities and peptides were identified by using nano-liquid chromatography coupled to mass spectrometry in tandem (nLC-MS/MS). Most of the identified peptides were smaller than 1000 Da and had different aromatic and hydrophobic amino acid residues. Their sequences were novel but some of them showed active domains previously reported in other bioactive peptides. The hexapeptide DGVVYY showed an IC₅₀ value of 2 µM in angiotensin-I converting enzyme (ACE-I) inhibitory activity, whereas the pentapeptide GQVPP displayed a 97% of DPPH activity at 0.4 mM. The results revealed that B. subtilis fermentation of tomato by-products could be a good strategy for obtaining added-value peptides that might be used as an ingredient in functional foods and nutraceuticals.