Converting Enzyme Activity Research Articles

Protein hydrolysates with ACE-I inhibitory activity from amaranth seeds fermented with Enterococcus faecium-LR9: Identification of peptides and molecular docking

One of the causes of hypertension is the activity of angiotensin-I converting enzyme (ACEI), making its inhibition a crucial strategy for controlling the disease. Protein hydrolysates are a known source of bioactive peptides that contribute to ACE-I inhibition. This study aims to evaluate the ACE-I inhibitory activity of amaranth seed hydrolysates after fermentation with Enterococcus faecium-LR9 and to compare it with Leuconostoc mesenteroides-18C6 and enzymatic hydrolysis (Alcalase®). The fermentation strategy with LR9 proved to be more effective in inhibiting ACE-I (79.1 ± 2.6 %) in vitro compared to 18C6 (68.0 ± 9.8 %) and enzymatic hydrolysis (69.4 ± 1.2 %). Consequently, these protein hydrolysates were subjected to in silico analysis, identifying 125 novel peptides. Bioinformatics and molecular docking analyses revealed 10 peptides with high ACE-I inhibitory potential. Among them, the IFQFPKTY and VIKPPSRAW peptides stood out. Therefore, E. faecium-LR9 is a promising strain for the release of bioactive peptides from seed storage proteins.

Biological Activities of Soy Protein Hydrolysate Conjugated with Mannose and Allulose.

The non-enzymatic conjugation of peptides through the Maillard reaction has gained attention as an effective method to enhance biological functions. This study focuses on two conjugate mixtures: crude soy protein hydrolysate (SPH) conjugated with mannose (SPHM) and crude soy protein hydrolysate conjugated with allulose (SPHA). These two mixtures were products of the Maillard reaction, also known as non-enzymatic glycation. In vitro experiments were conducted to evaluate the antioxidant, anti-pancreatic lipase, inhibition of Bovine Serum Albumin (BSA) denaturation, and anti-angiotensin converting enzyme (ACE) activities of these conjugated mixtures. The results indicate that conjugated mixtures significantly enhance the antioxidant potential demonstrated via the DPPH and FRAP assays. SPHA exhibits superior DPPH scavenging activity (280.87 ± 16.39 µg Trolox/mL) and FRAP value (38.91 ± 0.02 mg Trolox/mL). Additionally, both conjugate mixtures, at a concentration of 10 mg/mL, enhance the BSA denaturation properties, with SPHM showing slightly higher effectiveness compared to SPHA (19.78 ± 2.26% and 5.95 ± 3.89%, respectively). SPHA also shows an improvement in pancreatic lipase inhibition (29.43 ± 1.94%) when compared to the SPHM (23.34 ± 3.75%). Furthermore, both the conjugated mixtures and rare sugars exhibit ACE inhibitory properties on their own, effectively reducing ACE activity. Notably, the ACE inhibitory effects of the individual compounds and their conjugate mixtures (SPHM and SPHA) are comparable to those of positive control (Enalapril). In conclusion, SPHM and SPHA demonstrate a variety of bioactive properties, suggesting their potential use in functional foods or as ingredients in supplementary products.

Bioactive Properties of Enzymatic Gelatin Hydrolysates Based on In Silico, In Vitro, and In Vivo Studies.

This current study aims to analyze the potential bioactivities possessed by the enzymatic hydrolysates of commercial bovine, porcine, and tilapia gelatins using bioinformatics in combination with in vitro and in vivo studies. The hydrolysate with superior inhibition of angiotensin converting enzyme (ACE) activity was used to treat the D-galactose (DG)-induced amnesic mice. In silico digestion of the gelatins led to the identification of peptide sequences with potential antioxidant, ACE-inhibitory, and anti-amnestic properties. The results of in vitro digestion revealed that the <1 kDa peptide fraction of porcine gelatin hydrolysate obtained after 1 h digestion with papain (PP) (PP1, <1 kDa) potently inhibited ACE, acetylcholinesterase, and prolyl endopeptidase activities at 87.42%, 21.24%, and 48.07%, respectively. Administering the PP1 to DG-induced amnesic mice ameliorated the spatial cognitive impairment and Morris water maze learning abilities. The dentate area morphology in the PP1-treated mice was relatively similar to the control group. In addition, PP1 enhanced the antioxidant capacity in the DG-induced amnesic mice. This study suggests that PP1 could serve as a potential treatment tool against oxidative stress, hypertension, and neurodegenerative diseases.

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.

Development of Pomegranate Aloe Vera Juice: Pomalo

Abstract: Pomegranate juice is a good source of polyphenols and has good antioxidant potential, whereas, the studies on pomegranate juice have shown that it possesses antiatherogenic, antioxidant, antihypertensive, and anti-inflammatory properties. The literature also reported the major decrease in atherosclerotic lesion region in immune-deficient mice and intima media thickness in cardiac patients on medications, due to consumption of pomegranate juice. Whereas, in patients with type 2 diabetes, a reduction in lipid peroxidation was observed and in hypertensive patients, a systolic blood pressure and serum angiotensin converting enzyme activity was determined. Therefore, the study showed the potential cardioprotective advantages of pomegranate juice and suggests the inclusion of this juice in a diet for a healthy living. the composition of aloe vera and its role in development of functional foods. The colorless and watery gel-like consistency are the characteristics of aloe vera gel that makes it better option for blend beverages. The functional characteristics render aloe vera with broad range of application in the pharmaceutical, cosmetics and food sectors. The presence of antioxidants and hormones (auxins and gibberellins) in aloe vera, are responsible for preventing chronic diseases and wound healing properties by inducing the cell propagation, thus providing anti-inflammatory action, respectively. Saponins and salicylic acid present in it, provides antibacterial and antiseptic activity. The literature also reveals that emidine and aloin are the compounds present in aloe that act as antiviral, antibacterial and analgesic agent. Whereas, it also contains vitamins E, C and minerals such as, copper, selenium and zinc, along with enzyme brady kinase, fatty acids and sugar, essential and non-essential amino acids, 12 anthraquinones phenolic compounds. The most abundant monosaccharide and polysaccharides found in aloe vera are Mannose-6-phosphate, and glucomannans, respectively.

Toxicity study and effect of protein hydrolysates derived from black tilapia (Oreochromis placidus) on hypertensive induced mice

Protein hydrolysates are specific protein fragments, produced during enzymatic hydrolysis and can exert various biological functions. The present study investigated the acute toxicity study of protein hydrolysates derived from black tilapia (Oreochromis placidus) and their effect on hypertensive-induced mice. Protein hydrolysates were produced from black tilapia protein isolate through enzymatic hydrolysis. A single dose of protein hydrolysates at 2000 mg/kg of body weight was administered and any changes were observed for 14 days. During 14 days, there were no significant changes in liver enzyme content and kidney function content, adverse clinical signs and mortality. The effect of the administration of protein hydrolysates in hypertensive-induced mice was studied. The body weight, blood pressure, full blood count {red blood cell (RBC), white blood cell (WBC) and platelets} were observed. Hypertensive mice (systolic blood pressure; 161±3 mm/Hg) were fed with pellet consisting of protein hydrolysates at different concentrations as well as carvedilol and combination of carvedilol and protein hydrolysates and systolic blood pressure was monitored. After 28 days, there was a significant reduction of blood pressure in the group of carvedilol (107±4 mm/Hg), 5% protein hydrolysate (119±1 mm/Hg), 10% protein hydrolysate (123±1 mm/Hg), 20% protein hydrolysate (115±2 mm/Hg) and 10% protein hydrolysate in combination with carvedilol (103±2 mm/Hg). Red blood cells significantly increased in hypertension mice but no significant changes in white blood cells and platelets after 28 days. Administration of protein hydrolysates reduced red blood cell levels similar to control group. A significant increase in body weight was observed in hypertension mice administered with protein hydrolysates at different concentrations as well as carvedilol and a combination of carvedilol and protein hydrolysates compared to control group and hypertensive group. Studies on any changes in liver enzyme level, kidney function level and angiotensin converting enzyme (ACE) activity on blood serum were carried out. Results showed that treatment with protein hydrolysates on hypertensive-induced mice reduced liver enzyme levels (ALP, ALT and GGT) and kidney function levels (Na+, K+ and Cl-) to normal levels. ACE enzyme activity of hypertensive-induced mice in the serum was also reduced similar to control mice after being treated with protein hydrolysates.

Long-term intake of corn gluten meal protein hydrolysate attenuated hypertension development and modulated associated plasma metabolite levels in spontaneously hypertensive rats

This study evaluated the long-term antihypertensive effect of corn gluten meal protein hydrolysate (CGM-H) on spontaneously hypertensive rats (SHRs). Plausible pathways governing blood pressure were also evaluated based on untargeted metabolomic analysis. The casein diet containing 1 % of CGM-H and peptides obtained from ultrafiltration membranes attenuated the development of hypertension in SHRs after a 6-week oral administration with similar efficacy, while the control group showed progressive hypertension. Plasma renin and angiotensin converting enzyme (ACE) activity and total peroxides level of the corn peptides-treated groups decreased when compared with the control (p < 0.05). In addition, the corn peptides up-regulated antihypertensive metabolites such as prostaglandin K2 and 11-ketotestosterone, while corticosterone, biotin, and plasma fatty acids were down-regulated. This study demonstrates that corn peptides did not only inhibit ACE and renin activities, but also modulated the biosynthesis and metabolisms of fatty acids, sex hormones, and aldosterone, which would have contributed to attenuation of hypertension.

Exogenous Organic Matter Improves Potato Yield by Regulating the Microbiological Fertility Index

The nutrient availability of carbon (C), nitrogen (N), and phosphorus (P) has been decreasing due to a decline in the biological function of yellow soil, limiting potato yield (PY). Increasing biochar or organic fertilizer input is an effective way to improve soil microbiological fertility. However, indexes to regulate soil microbiological fertility using biochar and organic fertilizer individually or in combination and these indexes’ associations with PY remain unclear. In this study, four fertilization strategies were developed using the nutrient balance method: CK (recommended NPK fertilization), BC (NPK + biochar), OF (NPK + organic fertilizer), and BF (NPK + 1/2 biochar + 1/2 organic fertilizer). Using different fertilization strategies, the eco-stoichiometry characteristics of the soil microbial biomass and enzyme activity; the bioavailability of C, N, and P; and the differences in PY were investigated, and the direct and indirect effects of these factors on PY were determined over a two-year period. The results showed that exogenous organic matter input could considerably affect the stoichiometric ratios of soil microbial biomass; C; N; P; the stoichiometric ratios of C-converting, N-converting, and P-converting enzyme activities (expressed as BG+CBH, NAG+LAP, and AP, respectively); and the integrated enzyme index (IEI). The IEI was the highest in BF, followed by OF, BC, and CK. A significant positive correlation was found between the microbial biomass C, N, and P and their corresponding converting enzyme activities (p &lt; 0.05). The ln(BG+CBH):ln(NAG+LAP), ln(BG+CBH):lnAP, and ln(NAG+LAP):lnAP ratios were all higher than 1:1, but they approached 1:1 in the order of CK-BC-OF-BF. Compared to soil C and N, P-converting enzyme activity was the primary limiting factor for soil nutrient conversion in the study area. BF was less restricted by P and more balanced in its nutrient ratio. The microbial biomass C:N:P could affect PY in eight ways. (1) Microbial biomass C:N directly decreased PY, and microbial biomass C:P indirectly increased PY. (2) It could decrease C-converting enzyme activity, (3) decrease N availability to increase C-converting enzyme activity, (4) decrease P availability, or (5) decrease P availability to decrease the soil C:P-converting enzyme activity ratio. Microbial biomass N:P indirectly increased PY (6) by increasing the soil C:P-converting enzyme activity ratio, (7) by increasing C-converting enzyme activity, or (8) by increasing N availability to increase C-converting enzyme activity. Thus, BF is an effective strategy for regulating the soil microbiological fertility index; enhancing C, N, and P nutrient conversion; and increasing PY. The input of exogenous organic matter can alter the stoichiometric ratios of soil microbial biomass C, N, and P; the stoichiometric ratios of C-converting, N-converting, and P-converting enzyme activities; and nutrient availability, thus regulating PY. Microbial biomass N:P and soil C:P-converting enzyme activity ratios influence PY the most.

Inhibitory activity of Angiotensin-I converting enzyme (ACE-I) from partially purified Phaseolus lunatus peptide fractions

Phaseolus lunatus have proven to be a likely source of peptides with bioactivities that could be used to prevent and treat chronic degenerative diseases like arterial hypertension (AHT). Angiotensin-I converting enzyme (ACE-I) inhibition is essential for the AHT pathophysiology. In this work, the kinetic study of inhibition and inhibitory activity of ACE-I from peptide fractions partially purified from a protein hydrolysate from Phaseolus lunatus was performed. Hydrolysis was done by sequential enzymatic treatments with Pepsin-Pancreatin. The hydrolysates were ultrafiltered with 3 kDa and 5 kDa membranes, obtaining a fraction of 3–5 kDa which was later purified by gel filtration chromatography (GFC) and high-performance liquid chromatography (HPLC). The GFC fractions exhibited ACE-I inhibitory activities (ACE-I_I) up to 37.86% with an IC50 of 6.34 μg/mL. From HPLC purification, ACE-I_I up to 26.23% were obtained with an IC50 of 2.69 μg/mL. The kinetic parameters of the inhibition indicated that the peptides inhibit ACE-I through a competitive mechanism. The amino acids of the fractions evaluated presented Pro, Ala, Leu, and Ile, which can be part of the peptide fractions with ACE-I_I; with these results obtained these peptides could be used as functional foods related to the control and prevention of diseases related to AHT.

Underutilized Canadian wild berries as potential sources of lipophilic bioactive compounds with antihypertensive properties.

Traditional berries are small fruits and are widely distributed in the Canadian prairies. The current study investigates the lipophilic bioactive compounds such as fatty acids, phytosterols, and terpenes, and their bioactivities, such as lipid peroxidation, as well as the antihypertensive activities of fourteen underutilized Canadian wild berries. These berries include Saskatoon berries (Amelanchier alnifolia), gooseberries (Ribes hirtellum), wild grapes (Vitis riparia), blackcurrants (Ribes nigrum), redcurrants (Ribes rubrum), haskap berries (Lonicera caerulea), wild raspberries (Rubus idaeus), wild blueberries (Vaccinium angustifolium), chokeberries (Aronia melanocarpa), buckthorn (Rhamnus cathartica), highbush cranberries (Viburnum trilobum), chokecherries (Prunus virginiana), nannyberries (Viburnum lentago) and snowberries (Symphoricarpos albus). The fatty acids, phytosterols, and terpenes were identified using Gas Chromatography-Mass Spectrometry (GC-MS). Lipid peroxidation and the antihypertensive activity assessed by measuring the berries' angiotensin converting enzyme 1 (ACE1) inhibitory activity were determined using in vitro methods. Notably, wild grapes exhibited the highest (p < 0.05) total fat content (7659 ± 312 μg per g DW), followed by haskap berries (4650 ± 184 μg per g DW). Polyunsaturated fatty acids (PUFAs) were highest (p < 0.05) in wild grapes (74%). Predominant phytosterols and terpenes identified in Canadian wild berries included β-sitosterol, isofucosterol, phytol, and α-amyrin. Saskatoon berries and gooseberries showed a distinct phytosterol and terpene profile compared to the other wild berries. Snowberries demonstrated the highest (p < 0.05) lipid peroxidation and the lowest (p < 0.05) angiotensin converting enzyme (ACE1) activity. This research provides valuable insights into the lipophilic bioactive compounds and their potential activities in vitro of the Canadian wild berries, offering a foundation for further exploration and potential applications in the context of nutraceuticals and functional foods.

Plasma Affects Sugar Conversion during Storage of Citrus sinensis Osbeck: Melatonin Is a Key Factor

Background: Atmospheric pressure plasma as a green preservation technology for fruits and vegetables can effectively reduce the number of microorganisms on the surface of fruits and vegetables to achieve the effect of reducing the decay rate and prolonging the freshness period. In addition, plasma can affect the quality of fruits and vegetables and delay the aging of fruits and vegetables. However, the intrinsic mechanism by which plasma affects the quality of fruits and vegetables is unclear. Objective: The aim of this work is to observe the quality changes of Citrus sinensis Osbecks led by plasma treatment during storage period and to analyze the intrinsic mechanism behind it, for the purpose of providing a theoretical reference or the application of plasma in fruit preservation and quality enhancement. Methods: Postharvest Citrus sinensis Osbecks were treated with dielectric barrier discharge (DBD) for 5min, and then the total soluble solids, titratable acids and solid-acid ratios of fruit pulp during storage before and after treatment were measured using a hand-held digital refractometer, and an acid-base burette. Changes in melatonin, sucrose converting enzyme, and simple sugar content of fruit were measured with an ultraviolet-visible spectrophotometer. Results: It was found that the soluble solids and solid-acid ratio of Citrus sinensis Osbecks by DBD treated were significantly increased during storage, while titratable acid did not change significantly. Melatonin and sucrose converting enzyme measurements revealed that plasma treatment significantly increased melatonin content and sucrose converting enzyme activity in the pulp. Measurements of monosaccharides showed that the glucose and fructose contents of the treated Citrus sinensis Osbeck pulp increased, while the sucrose content decreased. Conclusion: The reactive oxygen and nitrogen species generated with DBD plasma can effectively increase the melatonin content in the pulp of Citrus sinensis Osbecks, thereby improving citrus quality including promoting sugar conversion and enhancing flavor.

ACE I/D genotype associates with strength in sarcopenic men but not with response to ACE inhibitor therapy in older adults with sarcopenia: Results from the LACE trial.

Angiotensin II (AII), has been suggested to promote muscle loss. Reducing AII synthesis, by inhibiting angiotensin converting enzyme (ACE) activity has been proposed as a method to inhibit muscle loss. The LACE clinical trial was designed to determine whether ACE inhibition would reduce further muscle loss in individuals with sarcopenia but suffered from low recruitment and returned a negative result. Polymorphic variation in the ACE promoter (I/D alleles) has been associated with differences in ACE activity and muscle physiology in a range of clinical conditions. This aim of this analysis was to determine whether I/D polymorphic variation is associated with muscle mass, strength, in sarcopenia or contributed to the lack of response to treatment in the LACE study. Sarcopenic individuals were recruited into a 2x2 factorial multicentre double-blind study of the effects of perindopril and/or leucine versus placebo on physical performance and muscle mass. DNA extracted from blood samples (n = 130 72 women and 58 men) was genotyped by PCR for the ACE I/D polymorphism. Genotypes were then compared with body composition measured by DXA, hand grip and quadriceps strength before and after 12 months' treatment with leucine and/or perindopril in a cross-sectional analysis of the influence of genotype on these variables. Allele frequencies for the normal UK population were extracted from 13 previous studies (I = 0.473, D = 0.527). In the LACE cohort the D allele was over-represented (I = 0.412, D = 0.588, p = 0.046). This over-representation was present in men (I = 0.353, D = 0.647, p = 0.010) but not women (I = 0.458, D = 0.532, p = 0.708). In men but not women, individuals with the I allele had greater leg strength (II/ID = 18.00 kg (14.50, 21.60) vs DD = 13.20 kg (10.50, 15.90), p = 0.028). Over the 12 months individuals with the DD genotype increased in quadriceps strength but those with the II or ID genotype did not. Perindopril did not increase muscle strength or mass in any polymorphism group relative to placebo. Our results suggest that although ACE genotype was not associated with response to ACE inhibitor therapy in the LACE trial population, sarcopenic men with the ACE DD genotype may be weaker than those with the ACE I/D or II genotype.

Effect of tofacitinib therapy on angiotensin converting enzyme activity in rheumatoid arthritis.

The Renin-Angiotensin-Aldosterone system (RAAS) has been implicated in the regulation of the cardiovascular system and linked to rheumatoid arthritis (RA). Little information has become available on the effects of Janus kinase (JAK) inhibition on RAAS. Here we studied the effects of 12-month tofacitinib treatment on angiotensin converting enzyme (ACE), ACE2 production and ACE/ACE2 ratios in RA along with numerous other biomarkers. Thirty RA patients were treated with tofacitinib in this prospective study. Serum ACE concentrations were assessed by ELISA. ACE2 activity was determined by a specific quenched fluorescent substrate. ACE/ACE2 ratios were calculated. We also determined common carotid intima-media thickness (ccIMT), brachial artery flow-mediated vasodilation (FMD) and carotid-femoral pulse-wave velocity (cfPWV) by ultrasound. C-reactive protein (CRP), rheumatoid factor (RF) and anti-citrullinated protein autoantibodies (ACPA) were also determined. All measurements were performed at baseline, as well as after 6 and 12 months of tofacitinib treatment. After the dropout of 4 patients, 26 completed the study. Tofacitinib treatment increased ACE levels after 6 and 12 months, while ACE2 activity only transiently increased at 6 months. The ACE/ACE2 ratio increased after 1 year of therapy (p < 0.05). Logistic regression analyses identified correlations between ACE, ACE2 or ACE/ACE2 ratios and RF at various time points. Baseline disease duration also correlated with erythrocyte sedimentation rate (ESR) (p < 0.05). One-year changes of ACE or ACE2 were determined by tofacitinib treatment plus ACPA or RF, respectively (p < 0.05). JAK inhibition increases serum ACE and ACE/ACE2 ratio in RA. Baseline inflammation (ESR), disease duration and ACPA, as well as RF levels at various time points can be coupled to the regulation of ACE/ACE2 ratio. The effect of tofacitinib on RAAS provides a plausible explanation for the cardiovascular effects of JAK inhibition in RA.

Functional and Bioactive Properties of Wheat Protein Fractions: Impact of Digestive Enzymes on Antioxidant, α-Amylase, and Angiotensin-Converting Enzyme Inhibition Potential.

This research aimed to determine the biofunctional properties of wheat flour (WF) protein fractions and modifications to the antioxidant, anti-α-amylase and anti-angiotensin-I converting enzyme (ACE) activities induced by the action of digestive endopeptidases in vitro. A molecular characterization of the most abundant protein fractions, i.e., albumins, glutelins-1, glutelins-2 and prolamins, showed that low- and high-MW polypeptides rich in cysteine, glutamic acid and leucine were present in albumins and glutelins, whereas low-MW subunits with a high proportion of polar amino acids prevailed in prolamins. Prolamins exhibited the second-highest water holding capacity (54%) after WF (84%), while albumins provided superior foam stability (76%). Prolamins, glutenins-1 and globulins demonstrated the highest antioxidant activity (up to 95%, 68% and 59%, respectively) both before and after hydrolysis with pepsin (P-H) or trypsin-chymotrypsin (TC-H). Prolamins, globulins and WF strongly inhibited α-amylase (>90%) before and after TC-H, and before P-H (55-71%). Moreover, P-H significantly increased α-amylase inhibition by albumins from 53 to 74%. The fractions with strong ACE inhibitory activity (70-89%) included prolamins and globulins after TC-H or P-H, as well as globulins before TC-H and WF before P-H. This novel evidence indicates that WF protein fractions and their peptide-enriched P and TC hydrolysates are excellent sources of multifunctional bioactives with antioxidant, antihyperglycemic and antihypertensive potential.

Okra seeds proteins: Amino acid profile, free radical scavenging activities and inhibition of diabetes and hypertensive converting enzymes indices

The study was aimed to determine bioactivity of okra seed proteins against oxidative stress, diabetes, and hypertension. Whole okra seed flour (OKPF), protein isolate (OKPI) and hydrolysate (OKPH, using proteolytic Lactic Acid Bacteria) were produced by standard methods. Samples were evaluated for protein contents, amino acids, in-vitro antioxidant, and enzymes (pancreatic lipase, α-amylase, α-glucosidase, and Angiotensin-1 converting) inhibitory properties. Protein content (g/100 g) of OKPH (97.45) was more than OKPI (80.09) and OKPF (26.42). In-vitro protein digestibility indicated that OKPH (87.17%) had the highest value followed by OKPI (77.63%) and OKPF (66.06%), respectively. Amino acid composition (mg/100 g protein), i.e., hydrophobic (32.36), aromatic (7.56), antioxidant (19.15), and branch chain (13.0) in OKPH were higher than in OKPF and OKPI. Functional properties of OKPH showed better attributes than in OKPI and OKPF, respectively. Protein hydrolysate (OKPH) exhibited highest antioxidant and free radical scavenging activity than in OKPI and OKPF. Sample OKPH exhibited highest percentage inhibition against carbohydrate-hydrolyzing and anti-hypertensive enzyme inhibition indices than in OKPF and OKPI. This study established that OKPH exhibited highest antioxidant, pancreatic lipase, angiotensin-1 converting, α-amylase and α-glucosidase enzyme activities. Hence, it may be suitable as nutraceutical agent for antidiabetic and antihypertension.

Limonin mitigates cardiometabolic complications in rats with metabolic syndrome through regulation of the IRS-1/GLUT4 signalling pathway

Limonin is a natural triterpenoid isolated from citrus fruit. In the present study, we examined the effects of limonin on cardiometabolic alterations in diet-induced metabolic syndrome. Metabolic syndrome was induced in rats by feeding them a high-fat (HF) diet plus 15% fructose in drinking water for 16 weeks. They were treated with limonin (50 or 100 mg/kg) (n = 8/group) for the final 4 weeks. Increases in body weight (BW), fasting blood glucose (FBG), serum insulin, total cholesterol (TC), blood pressure (BP), liver fat accumulation, and adipocyte hypertrophy, as well as oral glucose tolerance in rats with metabolic syndrome were alleviated by limonin treatment (p < 0.05). Limonin improved ejection fraction and left ventricular (LV) hypertrophy, and reduced angiotensin converting enzyme (ACE) activity and angiotensin II (Ang II) concentration in rats with metabolic syndrome (p < 0.05). It also reduced plasma tumour necrosis factor (TNF)-α, interleukin (IL)− 6, leptin, malonaldehyde (MDA), and superoxide generation, and increased catalase activity in rats with metabolic syndrome compared to controls (p < 0.05). Downregulation of insulin receptor substrate 1 (IRS-1) and glucose transporter type 4 (GLUT4) protein expression in epididymal fat pads and cardiac, liver, and gastrocnemius tissues was present in metabolic syndrome, and these were restored by limonin treatment (p < 0.05). In conclusion, limonin shows a potential effect in alleviating symptoms and improving cardiometabolic disorders. These beneficial effects are linked to the reduction of the renin-angiotensin system, inflammation, oxidative stress, and improvement of IRS-1/GLUT4 protein expression in the target tissue.

Oral Administration of Vitamin D3 Prevents Corneal Damage in a Knock-Out Mouse Model of Sjögren's Syndrome.

Vitamin D deficiency has been associated with dry eye development during Sjögren's syndrome (SS). Here, we investigated whether repeated oral vitamin D3 supplementation could prevent the corneal epithelium damage in an SS mouse model. 30 female mouse knock-out for the thrombospondin 1 gene were randomized (six per group) in untreated mice euthanized at 6 weeks as negative control (C-) or at 12 weeks as the positive control for dry eye (C+). Other mice were sacrificed after 6 weeks of oral vitamin D3 supplementation in the drinking water (1000, 8000, and 20,000 IU/kg/week, respectively). The C+ mice showed alterations in their corneal epithelial morphologies and thicknesses (p < 0.01 vs. C-), while the mice receiving 8000 (M) and 20,000 (H) IU/kg/week of vitamin D3 showed preservation of the corneal epithelium morphology and thickness (p < 0.01 vs. C+). Moreover, while the C+ mice exhibited high levels and activity of corneal tumor necrosis factor alpha converting enzyme (TACE), neovascularization and fibrosis markers; these were all reduced in the M and H mice. Oral vitamin D3 supplementation appeared to counteract the negative effect of TACE on corneal epithelium in a mouse model of SS-associated dry eye.

Assessment of angiotensin converting enzyme inhibitory activity and quality attributes of yoghurt enriched with Cinnamomum verum, Elettaria cardamomum, Beta vulgaris and Brassica oleracea

The new concept of functional foods has led to the varieties in the production of foods that provide not only basic nutrition, but can also warrant good health and longevity. This study deals with the production and evaluation of fortified yogurts’ with Cinnamomum verum, Elettaria cardamomum, Beta vulgaris and Brassica oleracea. The qualitative and quantitative phytochemical analysis of above mentioned plant extracts before using them into the preparation of functional yoghurt was carried out. The sensory evaluation of enriched yogurts with plant extracts carried out using 9 point hedonic scale. Comparative analysis between enriched yogurts and plain yogurt was carried. The results indicated increase in ash contents, water holding capacity, titratable acidity, total soluble solids, total phenolic content, tannin content, and total flavonoid content in fortified yogurt as compared to plain yogurt. In addition to this fortified yogurts showed greater antioxidant and antibacterial activity in contrast to plain yogurt. However, moisture contents, pH and susceptibility to syneresis of yogurt decreases with the addition of plant extracts. Shelf life of plain and fortified yogurt was determined both at room and refrigerated temperature. The results revealed that shelf life of fortified yogurt was greater as compared to plain yogurt. In silico analysis was carried out by using the galaxy web software. The results indicated that bioactive compounds including ascorbic acid, sinapinic acid, cinnamaldehyde and linalool acetate present in the flavored yogurts binds with angiotensin converting enzyme. All enriched yogurts showed higher anti-Angiotensin converting enzyme activity as compared to plain-yogurt.

STUDY OF FLAVONOIDS IN CAMEL THORN AND THEIR ACTIVITY IN ANGIOTENSIN-CONVERTING ENZYME REDUCTION

The article is dedicated to the study of polyphenolic compounds in extracts of camel thorn (Alhagi pseudoalhagi). Using UV spectroscopy and HPLC-MS/MS, the composition and content of flavonoids in camel thorn extracts were determined. Characteristic absorption bands for flavonoids were identified through optical spectroscopy. Data on the substance composition in the extract were obtained using the HPLC-MS/MS method. Semi-quantitative analysis of flavonoids was performed using the internal standard addition method with rutin. More than twenty flavonoids were detected in the 70% ethanolic extract. Rhamnetin 3-neohesperidoside and Isorhamnetin 3-neohesperidoside were the major components. The results could be applied in the production of antioxidant pharmaceuticals in the pharmaceutical industry. Comparison of the effects of camel thorn extract with the flavonoid taxifolin showed that the extract is equally effective in preventing early stages of atherosclerosis in the aorta caused by increased angiotensin-converting enzyme activity. At an extract concentration of 0.2%, the activity of the angiotensin converting enzyme in elderly rats and an imals treated with a NO-synthase inhibitor decreases to the values of young control rats.

P092 Risk factors for obstructive sleep apnea: A scoping review of systematic reviews

Abstract Introduction The high prevalence of obstructive sleep apnea (OSA) challenges public health and health care significantly. Summarizing the evidence and identifying research gaps on risk factors for OSA could focus efforts to reduce the disease burden. Methods We performed a scoping review to map the current evidence of OSA-related risk factors. Medline was searched systematically for systematic reviews/meta-analyses including observational and interventional studies, excluding reviews limited to paediatric populations. Results Of 974 abstracts, 49 eligible systematic reviews were retrieved, covering six major categories of risk factors, namely demographic(n=9), lifestyle(n=9), genetic(n=11), comorbidity-related(n=10), environmental(n=2), and other(e.g., protein level, surgery, n=12). Obesity/BMI and increasing age were major risk factors for OSA, however, longitudinal obesity trajectories or weight changes were not explored. Smoking was inconsistently associated with OSA. Alcohol consistently increased OSA severity(n=5). 5-HT2A(5-hydroxy-tryptamine), tumor necrosis factor- α, and angiotensin converting enzyme activity were associated with increased risk of OSA(n=4 for each). Comorbidity-related risk factors were identified including asthma, hypothyroidism, gastroesophageal reflux disease, depression while allergic rhinitis and Parkinson’s disease had null and negative effects, respectively. Menopause, ethnicity, and enlarged adenoids/tonsils are yet to be systematically synthesized. Overall, there was no review analyzing any longitudinal risk factor for OSA in the general population. Discussion Although this review supports the potential benefit of reducing OSA and its severity from weight loss and/or quitting smoking among the general population, there is an absence of data on longitudinal risk factor trajectories, which could help guide and strengthen public health policy.