Antioxidant and angiotensin-I converting enzyme inhibitory activity in the water-soluble protein extract from Petrovac Sausage (Petrovská Kolbása)

Novel antiosteoporotic peptides purified from protein hydrolysates of taihe black-boned silky fowl: By larval zebrafish model and molecular docking

The black-boned silky fowl (BSF) muscle protein hydrolysate was gained by alcalase. The hydrolysate could stimulate MC3T3-E1 cell proliferation, as well as enhance alkaline phosphatas (ALP) activity and deposits of minerals. After isolation and purification, 55 peptide sequences with Mascot score over 40 were identified. Combined with molecular docking simulation and molecular dynamics analysis, two novel peptides (PASTGAAK and PGPPGTPF) were identified with the lowest binding energy of -4.99 kcal/mol and -3.07 kcal/mol with receptor BMPR1A of BMP-2/Smad pathway, showing the ability to increase BMPR1A stability. Moreover, both PASTGAAK and PGPPGTPF revealed strong anti-osteoporosis activities in the zebrafish model induced by dexamethasone. Additionally, the identified peptides could be beneficial for the differentiation of MC3T3-E1 cell for upregulating the expression of some osteoblast-related genes and proteins by stimulating BMP-2/Smad pathway. Overall, the two newly identified peptides could be the potential candidate to prevent osteoporosis.

Potential Antioxidant and Angiotensin I-converting Enzyme Inhibitory Activity in Crust of Dry-aged Beef

Antioxidant activity, angiotensin I-converting enzyme (ACE) inhibitory activity, and protein profile of crust (the dried surface of dry-aged beef) were evaluated compared to unaged, wet-, and dry-aged beef. Antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-di-(3-ethylbenzthiazoline sulfonate) radical scavenging activities, ferric reducing antioxidant power, and ferrous ion chelating activity. The crust samples showed the greatest (P < 0.05) ACE inhibitory and antioxidant activity resulting from the three different mechanisms of action (radical scavenging, non-radical redox potential activity, and metal chelating) among the treatments. Small molecular weight protein bands and small peptides (<3 kDa) indicating potent bioactivity were evident in the myofibrillar protein profile of crust samples. The lowest (P < 0.05) ACE inhibitory activity was observed in unaged beef. The results indicate that crust could be utilized in various areas as a functional ingredient possessed antioxidant and ACE inhibitory activity instead of being discarded. In addition, dry aging can use for generation of functional ingredient from beef as the regime.

Bioactive Properties of Novel Probiotic Lactococcus lactis Fermented Camel Sausages: Cytotoxicity, Angiotensin Converting Enzyme Inhibition, Antioxidant Capacity, and Antidiabetic Activity

Fermented products, including sausages, provide several health benefits, particularly when probiotics are used in the fermentation process. This study aimed to examine the cytotoxicity (against Caco-2 and MCF-7 cell lines), antihypertensive activity via angiotensin-converting enzyme (ACE) inhibition, antioxidant capacity, antidiabetic activity via α-amylase and α-glucosidase inhibition, proteolysis rate, and oxidative degradation of fermented camel and beef sausages in vitro by the novel probiotic Lactococcus lactis KX881782 isolated from camel milk. Moreover, camel and beef sausages fermented with commercial starter culture alone were compared to those fermented with commercial starter culture combined with L. lactis. The degree of hydrolysis, antioxidant capacity, cytotoxicity against Caco-2 and MCF-7, α-amylase, α-glucosidase, and ACE inhibitory activities were higher (p<0.05) in fermented camel sausages than beef sausages. In contrast, the water and lipid peroxidation activity were lower (p<0.05) in camel sausages than beef sausages. L. lactis enhanced the health benefits of the fermented camel sausages. These results suggest that camel sausage fermented with the novel probiotic L. lactis KX881782 could be a promising functional food that relatively provides several health benefits to consumers compared with fermented beef sausage.

Cowpea: an overview on its nutritional facts and health benefits

Cowpea (Vigna unguiculata) is a legume consumed as a high-quality plant protein source in many parts of the world. High protein and carbohydrate contents with a relatively low fat content and a complementary amino acid pattern to that of cereal grains make cowpea an important nutritional food in the human diet. Cowpea has gained more attention recently from consumers and researchers worldwide as a result of its exerted health beneficial properties, including anti-diabetic, anti-cancer, anti-hyperlipidemic, anti-inflammatory and anti-hypertensive properties. Among the mechanisms that have been proposed in the prevention of chronic diseases, the most proven are attributed to the presence of compounds such as soluble and insoluble dietary fiber, phytochemicals, and proteins and peptides in cowpea. However, studies on the anti-cancer and anti-inflammatory properties of cowpea have produced conflicting results. Some studies support a protective effect of cowpea on the progression of cancer and inflammation, whereas others did not reveal any. Because there are only a few studies addressing health-related effects of cowpea consumption, further studies in this area are suggested. In addition, despite the reported favorable effects of cowpea on diabetes, hyperlipidemia and hypertension, a long-term epidemiological study investigating the association between cowpea consumption and diabetes, cardiovascular disease and cancer is also recommended. © 2018 Society of Chemical Industry.

Isolation and identification of angiotensin I-converting enzyme inhibitory peptides derived from thermolysin-injected beef M. longissimus

Objective

This study identified angiotensin I-converting enzyme (ACE) inhibitory peptides in beef M. longissimus injected with thermolysin (80 ppm) and stored for 3 days at 5°C.

Methods

Crude peptides (molecular weight <3 kDa) were obtained from the thermolysin hydrolysate and separated into seven fractions. Fraction V showing the highest ACE inhibitory activity was further fractionated, yielding subfractions V-15, V-m1, and V-m2, and selected for superior ACE inhibitory activity. Finally, twelve peptides were identified from the three peak fractions and the ACE inhibitory activity (IC₅₀) of each peptide was evaluated.

Results

The Leu-Ser-Trp, Phe-Gly-Tyr, and Tyr-Arg-Gln peptides exhibited the strongest ACE inhibitory activity (IC₅₀ values of 0.89, 2.69, and 3.09 mM, respectively) and had higher concentrations (6.63, 10.60, and 29.91 pg/g; p<0.05) relative to the other peptides tested.

Conclusion

These results suggest that the thermolysin injection process is beneficial to the generation of bioactive peptides with strong ACE inhibitory activity.

Acute Toxicity, Antioxidant, and Antifatigue Activities of Protein-Rich Extract from Oviductus ranae

The paper investigated the preparation, amino acid composition, acute toxicity, and in vitro and in vivo antioxidant, coupled with in vivo antifatigue activities of protein-rich extract of Oviductus ranae (PEOR). The results indicated that PEOR possesses high-safety property with maximum tolerated dose (MTD) higher than 20 g/kg in mice, shows weak scavenging capacities against hydroxyl, superoxide anion, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, as well as ferric-reducing antioxidant power in vitro, but exerts strong antioxidant effect in ethanol-induced oxidative stress mice model; it can decrease malonaldehyde (MDA) and protein carbonyl (PCO) formation and increase total superoxide dismutase (T-SOD) activity and glutathione (GSH) synthesis. Besides the strong in vivo antioxidant activity, PEOR in a dose of 400 mg/kg also has antifatigue effect in mice, and it can prolong the exhaustive swimming time, reduce the elevated blood urea nitrogen (BUN) and blood lactic acid (BLA) caused by intense exercise. The in vivo activity of PEOR may be contributed by its absorbed amino acids, due to the fact that eight antioxidant amino acids and twelve glucogenic ones were found in it. This study will provide an evidence for the clinical use of PEOR as a dietary supplement for antioxidant and antifatigue in the same oral dose (400 mg/kg).

Effect of Lactobacillus acidophilus Bauer and Bifidobacterium animalis ssp. lactis BB12 on proteolytic changes in dry-cured loins

The effect of the potentially probiotic bacteria strain of Lactobacillus acidophilus Bauer and probiotic bacteria Bifidobacterium animalis ssp. lactis BB12 on proteolytic changes of proteins in dry-cured loins during fermentation and cold storage was studied. Results of the conducted tests demonstrated that the use of probiotic bacteria for the production of dry-cured meats impacts the generation of products of protein proteolysis with high antioxidant activity. The highest antioxidant activity of peptides after fermentation and cold storage was observed in the loin with the strain B. animalis ssp. lactis BB12 and the loin with the mixture of strains L. acidophilus Bauer and B. animalis ssp. lactis BB12. Qualitative analysis of peptides demonstrated that peptides with weight below 3.5 kDa are characterized by the highest capacity of quenching the ABTS cation radical, including the peptides in loins with the strain B. animalis ssp. lactis BB12.

Recent Research in Antihypertensive Activity of Food Protein-derived Hydrolyzates and Peptides

Year to year obesity prevalence, reduced physical activities, bad habits/or stressful lifestyle, and other environmental and physiological impacts lead to increase in diseases such as coronary heart disease, stroke, cancer, diabetes, and hypertension worldwide. Hypertension is considered as one of the most common serious chronic diseases; however, discovery of medications with high efficacy and without side effects for treatment of patients remains a challenge for scientists. Recent trends in functional foods have evidenced that food bioactive proteins play a major role in the concepts of illness and curing; therefore, nutritionists, biomedical scientists, and food scientists are working together to develop improved systems for the discovery of peptides with increased potency and therapeutic benefits. This review presents a recent research carried out to date for the purpose of isolation and identification of bioactive hydrolyzates and peptides with angiotensin I converting enzyme inhibitory activity and antihypertensive effect from animal, marine, microbial, and plant food proteins. Effects of food processing and hydrolyzation conditions as well as some other impacts on formation, activity, and stability of these hydrolyzates and peptides are also presented.

The Effect of the Addition of Encapsulated Collagen Hydrolysate on Some Quality Characteristics of Sucuk

The effect of addition commercial fish collagen hydrolysate and encapsulated fish collagen hydrolysate on the quality characteristics of sucuk (a traditional Turkish dry-fermented sausage) was investigated. Fish collagen hydrolysates were encapsulated with maltodextrin (MD) which has two different dextrose equivalent (12DE and 19 DE), with two different types of core/coating material ratios (10% peptide : 90% MD, 20% peptide : 80% MD). Than six group of sucuk dough (control, peptide, MD1210, MD1220, MD1910, MD1920) prepared and naturally fermented. The effects of the ripening period (28 d), treatment (peptide and encapsulated peptide addition) ‘ripening period × treatment’ interaction on sucuk’s pH, lactic acid contents, a_w values and moisture contents were statistically significant (p<0.01). The pH, moisture and a_w decrease and lactic acid concentration increses during ripening period. The highest pH was observed with peptide added group (5.41), and encapsulated peptide added groups (4.76-4.77) were lower than the control group (5.26). Lactic acid concentration was affected from treatment and all treatment groups lactic acid concentration (0.185-0.190%) were higher than the control group (0.164%). Antioxidant and Angiotensin converting enzyme inhibition activities of water soluble protein extracts were significantly (p<0.01) increased during ripening time. Antioxidant activity reached the highest level at 28^th d. There was no significant increase observed after fermentation for both activities. Antioxidant activity of encapsulated peptide added (%39.56-40.48) groups were higher than control (34.28%) and peptide added (33.99%) groups except MD1920 (38.30%). The effect of the ripening period of the sucuk samples on TBA values was found to be statistically significant (p<0.01) while treatment and ‘ripening period × treatment’ interaction were not to be significant (p<0.05). The value of hardness was the highest in the encapsulated peptide added groups (29.27, 35.83 N), and it was 20.40 N and 15.41 N in the peptide added group and the control group respectively.