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Simulated gastrointestinal hydrolysis of hemp seed proteins using pepsin and pancreatin followed by membrane ultrafiltration fractionation yielded fractions with peptide sizes of <1, 1–3, 3–5, and 5–10kDa. Analysis of in vitro antioxidant properties showed that the hemp seed protein hydrolysate (HPH) exhibited a significantly weaker (p<0.05) scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals when compared to the fractionated peptides. Metal chelation activity of the HPH was significantly greater (p<0.05) than the activities of fractionated peptides. Fractionation of the HPH led to significant (p<0.05) improvements in ferric reducing power, DPPH, and hydroxyl radical scavenging radical activities but decreased metal chelation capacity. Peptide fractions with longer chain lengths (3–5 and 5–10kDa) had better metal chelation and ferric reducing power than the <1, and 1–3kDa fractions. HPH and all the peptide fractions significantly inhibited (p<0.05) linoleic acid oxidation when compared to the control. Glutathione (GSH) had significantly greater (p<0.05) ferric reducing power, and scavenging of hydroxyl and DPPH radicals when compared to HPH and fractionated peptides. In contrast, HPH and peptide fractions >3kDa had significantly higher (p<0.05) metal chelation activity than GSH. The results show the potential use of HPH and peptide fractions of defined size for the treatment of oxidative stress-related diseases.
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... 2.12. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) Radical Scavenging Assay DPPH radical assay was used to determine antioxidant properties of protein hydrolysates according to Girgih et al. [29]. A 100 µL aliquot of hydrolysates in methanol (5 mg/mL) was mixed with 0.1 mM DPPH methanolic solution. ...
... Metal chelating activity was measured based on Girgih et al. [29]. A 200 µL aliquot of hydrolysates with 2 mM FeCl 2 µL and 5 mM Ferrozine were mixed for 10 min in the dark. ...
... Reducing power of MSJ and MSJ hydrolysates was determined according to Girgih et al. [29]. A 250 µL aliquot of hydrolysates (5 mg/mL) was dissolved in 250 µL of 0.2 M sodium phosphate buffer (pH 6.6) (1 mg/mL) and mixed with 250 µL of 1% (w/v) potassium ferricyanide solution followed by incubation for 20 min at 50 • C. Afterwards, 10% (w/v) TCA (250 µL) were added into the mixture and centrifuged at 3000 rpm for 5 min. ...
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Mackerel (Scomber australasicus) steaming juice (MSJ) can be a good source of proteins. However, it is often treated as food waste during the canning process. The objective of this study was to investigate the Angiotensin-I converting enzyme (ACE-I) inhibitory and antioxidant activities from MSJ hydrolysates using in silico and in vitro approaches. Proteins extracted from MSJ were identified by proteomic techniques, followed by sulfate polyacrylamide gel electrophoresis (SDS-PAGE), in-gel digestion, tandem mass spectrometry and on-line Mascot database analysis. Myosin heavy chain (fast skeletal muscle), actin, myosin light chain 1 (skeletal muscle isoform), collagen alpha-2(I) chain, tropomyosin alpha-1 chain, beta-enolase, fructose-bisphosphate aldolase A and glyceraldehyde-3- phosphate dehydrogenase were identified and further analyzed using BIOPEP-UWM database. In silico results indicated that MSJ proteins had potential bioactive peptides of antioxidant and ACE-I inhibitory activities. MSJ was then hydrolyzed using six proteases (papain, pepsin, proteinase k, alcalase, bromelain, thermolysin). In particular, pepsin hydrolysates (5 mg/mL) showed the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (61.54%) among others. Alcalase hydrolysates (5 mg/mL) exhibited the highest metal chelating activity (89.76%) and proteinase K hydrolysates (5 mg/mL) indicated the highest reducing power activity (1.52 abs). Moreover, pepsin hydrolysates (0.1 mg/mL) possessed the highest ACE inhibitory activity (86.15%). Current findings suggest that MSJ hydrolysates can be a potential material to produce ACE-I inhibitory and antioxidant peptides as nutraceutical or pharmaceutical ingredients/products with added values.
... The free radicals scavenging activity of aqueous extract of the bread samples on 2, 2-Diphenyl-1-picryhydrazyl (DPPH) was determined as described by Girgih et al. [36]. The free radical scavenging activity of the bread samples against 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) was determined using modified method of Re et al. [37]. ...
... The free radical scavenging activity of the bread samples against 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) was determined using modified method of Re et al. [37]. The metal chelating activity of bread aqueous extract samples were determined according to the method of Girgih et al. [36]. The hydroxyl radical scavenging activity of the bread aqueous extract samples was determined as described by Girgih et al. [36]. ...
... The metal chelating activity of bread aqueous extract samples were determined according to the method of Girgih et al. [36]. The hydroxyl radical scavenging activity of the bread aqueous extract samples was determined as described by Girgih et al. [36]. The Ferric-reducing antioxidant power (FRAP) activity of the bread aqueous extract samples was determined using method of Mau et al. [38]. ...
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The research was designed to ascertain the potential of bambara groundnut inclusion in wheat bread to improve antioxidant activity, modulate carbohydrate hydrolyzing enzyme activities, and lower glyceamic index/ load. Protein (g/100 g) (11.2—11.73) and energy value (kcal/100 g) (421.5—435.5) of the bread were significantly higher than commercial wheat flour bread (CWF—10.45; 388.7). However, developed experimental bread samples exhibited higher growth performance in rats, free radical scavenging potentials, inhibitory activities against carbohydrate hydrolyzing enzymes and low glycemic index than other bread samples. Nevertheless, experimental bread samples were rated lower compared with the controls samples as regards organoleptic properties. The study authenticates that WBO3—25% wheat, and 75% bamabara groundnut WBO3 exhibits higher potentials as regards nutritional composition, growth indices, free radical scavenging potentials, ability to modulate carbohydrate hydrolyzing enzyme and lower glycemic index/ load. Hence, WBO3 may be recommended as functional bread for hyperglycemia prevention/ management.
... smaller-sized peptides exhibited higher bioactivity than biggersized peptides (Girgih et al., 2010Nwachukwu et al., 2014;Vilcacundo et al., 2019). The strong potency of low molecular weight (LMW) peptides during in vivo and in vitro assessments of bioactive properties of protein hydrolysates has been explained to be a result of easy passage within the gastrointestinal tract, TA B L E 1 Amino acid composition of pea protein hydrolysates from different enzymes (g/100 g) increased synergistic effect within fractionated peptides, and improved homogeneity as opposed to the greater presence of antagonistic effect in unfractionated peptides (Hu et al., 2019;Nwachukwu et al., 2014). ...
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This study optimized the enzymatic hydrolysis of yellow field pea proteins using alcalase (ACH), chymotrypsin (CHH), flavourzyme (FZH), pancreatin (PCH), pepsin (PEH), and trypsin (TPH) to obtain hydrolysates and ultrafiltered fractions (<1, 1–3, 3–5 and 5–10 kDa) that possess antioxidant plus acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities. The hydrolysates exhibited varying degrees of radical scavenging and inhibition of linoleic acid peroxidation, as well as cholinesterase inhibition activities but the potency generally improved by >10% after UF separation into peptide fractions. ACH, FZH, and PEH exhibited significantly (p < .05) higher (20%–30% increases) radical scavenging activities than the other hydrolysates. The 1 and 3 kDa UF fractions of ACH, FZH, and PEH inhibited ~20%–30% AChE activity, while ACH, PCH, TPH, and PEH inhibited ~20%–40% BuChE activity. We conclude that the pea protein hydrolysates and their peptide fractions possess multifunctional properties with potential use against neurodegenerative disorders. Practical applications Alzheimer's disease (AD) has multiple pathological pathways in addition to the loss of acetylcholine (ACh) catalyzed by acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The presence of severe oxidative stress triggered by lipid peroxidation and formation of free radicals is a common trait in AD patients. The concept of AChE and BuChE inhibition as an approach toward AD amelioration involves the use of compounds with a similar structure to ACh, the natural substrate. Peptides derived from food proteins consist of ester bonds with structural similarity to ACh and theoretically possess the ability to interact with AChE and BuChE. Results from the present study imply that pea protein‐derived peptides are potential candidates for use as inhibitors of AChE and BuChE activities, with application in the prevention and management of AD.
... Ferric reducing antioxidant activity (FRAP) was determined according to Zhang et al. [26] method. The hydroxyl free radical scavenging activity of MCSs extract was determined according to the method reported by Girgih et al. [27]. ...
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Ability of plants to prevent degenerative diseases is based on the biological activities of their bioactive components. Bioactive components are more biologically available for the body to utilize when the plant undergo processing which aid their potential in treatment and management of several chronic diseases like diabetes. Thus, the present study evaluated the effect of processing (cooking and roasting) on antioxidant activity and blood glucose reduction potential of Malabar Chestnut Seeds (MCSs) in Streptozotocin (STZ) Induced Diabetic Rats. Fresh MCSs were divided into three portion. First portion were cooked at 100 °C for 20 min (Cooked), second portion were roasted at 200 °C for 40 min (Roasted) while, the last portion were used as fresh MCSs (Raw). Rattus norvegicus were obtained and grouped in number of 5 rats per sample. The antioxidant activities assay shows that processing (cooking and roasting) enhanced free radical scavenging ability of MCSs samples against DPPH which ranged from 41.27% in raw to 58.77% in roasted. Glycemic index of cooked and roasted MCSs (42.29% and 37.77%) were also observed to be lower than 44.78% obtained in raw MCSs. Low density lipoprotein concentration (99.74 and 86.78 mg/dl) of rats fed on processed (cooked and roasted) MCSs samples shows ameliorating potential compared with 113.01 mg/dl obtained in rats induced with STZ and fed with Chow only. Highest blood glucose level reduction potential (73.90%) was obtained in roasted MCSs followed by cooked MCSs (70.09%). These values were higher than 0.43% and 67.45% obtained in STZ induced rats fed on chow and acarbose (2.0 mg/day) respectively. The study established that processing of MCSs enhanced free radical scavenging abilities, lower glycemic index (
... It owes its properties to the peptide fractions: Trp-Val-Tyr-Tyr (tetrapeptide) and Pro-Ser-Leu-Pro-Ala (pentapeptide). Additionally, fractionated peptides showed higher chelating activity than glutathione in studies [36,37]. Such a strong radical scavenging process may be related to the extension of the life of bees in our experiment (given the great antioxidant effects for various forms of the processed hemp raw materials). ...
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We examined the effect of hemp extract on the activity of the antioxidant system (catalase, peroxidase, glutathione, superoxide dismutase, and total antioxidant capacity) in the hemolymph of adult honey bees (Apis mellifera). The bees were divided into three groups: (1) an experimental group fed with pure sugar syrup with cotton strips soaked with hemp extract put inside the cage; (2) an experimental group fed with a mixture of sugar syrup with hemp extract; and (3) a control group fed with a mixture of sugar and a water–glycerine solution. Hemolymph samples were collected on the 1st day of this study and then every week, until all bees in the group died. The activities of all antioxidant enzymes were higher for the experimental groups, compared to those for the control group. The highest antioxidant activities were noted in the group supplemented with cannabis with the use of syringes. Supplementation with hemp also increased the lifespan of bees in this group compared to that of the bees consuming only sugar syrup (control: 35 days), with 49 and 52 days for groups of cannabis on strips and in syrup, respectively. Hemp extract, thanks to its antioxidant properties, increased the activities of key antioxidant enzymes that protect the bee’s organisms against free radicals and thus delay the aging processes.
... Conversely, the metal-chelating antioxidant power of the hydrolysates was higher than that of all the separated peptide fractions and GSH (Girgih et al., 2013). Similarly, the higher molecular weight peptide fractions of the hydrolysates (>10 kDa) inhibited linoleic acid oxidation better than low molecular weight peptide fractions (<10 kDa) and GSH (Girgih et al., 2012). Furthermore, the ultrafiltration-based separation of specific peptides in the most active low molecular weight peptide fraction (<1 kDa) yielded 23 short-chain peptides with moderate to high antioxidant activities. ...
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Protein‐energy malnutrition is a global challenge that demands urgent attention, especially with the increasing population growth and unmatched food security plans. One strategy is to expand the list of protein sources, such as neglected and underutilized crops, with high protein content. A good number of plant proteins, in addition to their nutritional benefits, exert therapeutic properties as seen in seeds derived from legumes and emerging sources such as hemp. In this review, the transepithelial transport, functional, and biological properties of hempseed proteins (HSPs) and peptides were discussed. The review also described the potential safety issues of incorporating hempseeds in food products. Due to the multitargeted effects of hempseed‐derived proteins and their peptides against many chronic diseases, and their functional properties, current knowledge shows that hempseed has tremendous potential for functional food and nutraceutical applications. Practical applications The alarming rate of malnutrition and the attendant health consequences demand that underexploited nutrient‐rich crops should be incorporated as part of our common dietary sources. Among these crops, hempseed is gaining attention as an emerging source of proteins and peptides with promising potential in prevention and management of chronic diseases such as diabetes, hypertension, cancer, hypercholesterolemia, obesity, and diseases whose etiology involves oxidative stress and inflammation. Fortunately, a growing body of research evidence is demonstrating that hempseed is a reservoir of proteins and peptides with nutraceutical potentials for curbing life‐threatening diseases.
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To further improve the capability of flow electrochemistry, the multistage plug-flow electrochemical membrane reactor (PF-ECMR) with membrane electrode was developed for enhancing the oxidation of cyclohexane (CHA) to produce KA oil (mixture of cyclohexanol and cyclohexanone). The catalytic results demonstrated that the CHA conversion and the selectivity to KA oil were up to 95.6% and > 99%, which was the highest in comparison with most of the state-of-the-art catalytic processes reported in the previous works. The mechanism was explored by density functional theory (DFT) calculations, indicating the auxo-action effect of cyclohexanone was beneficial for the formation of cyclohexyl hydroperoxide so as to enhance the CHA conversion. The excellent performance of PF-ECMR was also attributed to the staggered electric field and the accumulative effect of the multi-electrodes. This study provided a successful case of a combination of theoretical prediction and experimental verification together for organic synthesis.
Chapter
The increase in the world population, together with the new trends toward the plant consumption, as well as the concern for the environment and the revolution in the food industry, has made hemp one of the most promising substrates to be used as an ingredient in the upcoming years. Nutritionally, it is very suitable for human consumption, both in macro and micronutrients, and at an environmental level it is a very interesting alternative due to the low impact it has. Currently, very little literature is available on hemp protein, when compared to other commonly used substrates. In this review, we aimed to summarized its definition, origin, nutritional profile, safety issues, technological modification by processing, bioactive peptides derived from it, impact of its inclusion in matrices and market situation among other topics. It is important to mention how the information available on hemp increases every year, and there are already products on the market that include it in their composition, giving relevance to this substrate with much to be exploited today. Not only hemp protein is suitable for human consumption, but also its production is environmentally sustainable, and further research has to be carried out in the near future.
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Native and heated soy protein isolate was hydrolyzed with 3 purified (pepsin, papain, and chymotrypsin) and 3 crude (Alcalase®, ProtamexTM, and FlavourzymeTM) proteases. The hydrolysates were incubated (37 °C, 1 h) with a liposome-oxidizing system (50 μM FeCl3/0.1 mM ascorbate, pH 7.0) to test antioxidant activities by determining the concentrations of TBARS. Degree of hydrolysis of SPI hydrolysates ranged from 1.7 to 20.6%. Both hydrolyzed and nonhydrolyzed SPI decreased TBARS (by 28 to 65%), except for papain-hydrolyzed samples. Samples of chymotrypsin- and Flavourzyme-hydrolyzed (0.5 h) preheated SPI had the greatest inhibitory effect on lipid oxidation.
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The renin-angiotensin system (RAS) is the major determinant of blood pressure in humans, of which angiotensin converting enzyme (ACE) is a major factor. Alterations in the normal functioning of the RAS can lead to significant effects on the cardiovascular system, especially the undesirable excessive increase in blood pressure. In general, excessive activity of ACE leads to increased formation of angiotensin II, the major pressor agent in blood vessels and if left uncontrolled leads to development of hypertension. Clinical management of hypertension uses ACE inhibitors that block or reduce formation of angiotensin II, thereby lowering blood pressure. Recent developments have identified bioactive peptides and other natural plant compounds as possible alternatives to the use drugs in the management of hypertension. There is convincing evidence that confirms the ability of these naturally-occurring agents to inhibit activity of ACE in vitro and to actually cause reduction in blood pressure in experimental animals. The use of natural compounds could be more desirable since they elicit less severe side effects and may be cheaper to produce in the long run due to the abundance of plant resources. This review discusses the production, structural characteristics, ACE-inhibitory activity and physiological relevance of some of the natural plant products that have been reported in the literature as potential antihypertensive agents.
A number of variations were evaluated in the techniques and procedures of the classical 6N hydrochloric acid, 110°C, 24 h hydrolysis of protein. Variations included the use of glass tubes with Teflon-lined screw caps as the hydrolysis vessel, high-temperature short-time hydrolysis, performic acid oxidation of cystine and methionine, multiple hydrolysis times at 145°C, and interlaboratory preparation of hydrolysates. A diverse sample set used in the study included a range of protein-containing matrices, and automated ionexchange chromatography was used for the amino acid analysis. Results show that for hydrolysis in glass tubes with Teflon-lined screw caps at 110°C for 24 h, recoveries of amino acids were in good agreement with recoveries by classical hydrolysis in sealed glass ampoules at reduced pressure. Recoveries from a higher temperature hydrolysis, i.e., 145°C for 4 h and using sealed ampoules, were also in agreement with 110°C, 24 h, sealed ampoule results; the former procedure yielded increased isoleucine and valine and decreased serine and threonine values. Glass tubes with Teflon-lined screw caps for hydrolysis were found to be a practical and convenient alternative to sealed glass ampoules; the improved precision with the former was probably due to the simplicity of the method. The average recovery of cystine from a wide range of matrices without the use of performic acid was 55.5% compared with results obtained with performic acid oxidation. Similarly, methionine is preferably analyzed as methionine sulfone. Interlaboratory evaluation of 145°C, 4 h hydrolysis, in which one laboratory used sealed ampoules and the other laboratory used Teflon-lined screw-cap tubes, demonstrated excellent agreement of amino acid values.
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A procedure simplifying the treatment of barytic hydrolysate prior to chromatographic analysis of tryptophan was tested on eight samples of foods and feedstuffs. It involves the addition of 5-methyl-tryptophan as internal standard to the mixture subjected to hydrolysis, the dilution of a very small volume (3-mu-L) of liquid phase of cold (0-degrees-C) hydrolysate with 1 mL of pH 4.5 buffer, and the chromatography of aliquots after dilution. Tryptophan was evaluated from 5-methyltryptophan. The simplified procedure compared with the conventional one, using the remainder of hydrolysate and requiring acidification, quantitative transfer, and clarification, gave identical results irrespective of samples. It is convenient and precise and leads to routine determination of tryptophan of a large number of samples.
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Quinoa protein concentrate was hydrolyzed with alcalase to obtain a hydrolysate that was fractionated by ultrafiltration using 10000- and 5000-molecular-weight cutoff membranes. Functional properties of the protein concentrate, protein hydrolysate, and membrane permeates were compared at different pH values. Protein solubility of the hydrolysate and membrane permeates were significantly higher (P= 0.05) than that of the protein concentrate. The protein concentrate had a significantly higher (P= 0.05) emulsifying activity index than the protein hydrolysate and membrane permeates. Membrane fractionation of the protein hydrolysate into lower-molecular-weight pep tides significantly reduced (P= 0.05) foaming properties, but it improved radical scavenging activity and the ability to inhibit the activity of angiotensin-converting enzyme.
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Wheat germ protein hydrolysates were prepared by protease hydrolysis, ultrafiltration and dynamical adsorption of resin. The total amount of amino acids in 100 g wheat germ protein hydrolysates is 93.95 g. Wheat germ protein hydrolysates are primarily composed of 4 fractions: 17.78% in the relative molecular mass range of 11 563–1 512, 17.50% in 1512 – 842, 27.38% in 842 – 372 and 30.65% in 372 – 76, respectively. The antioxidant properties of wheat germ protein hydrolysates were evaluated by using different antioxidant tests in vitro. 1.20 g/L wheat germ protein hydrolysates exhibit 78.75% inhibition of peroxidation in linolei acid system; and 1.6 g/L wheat germ protein hydrolysates show 81.11% scavenging effect on the 1,1-diphenyl-2-picrylhrazyl radical. The reducing power of 2.50 g/L wheat germ protein hydrolysates is 0.84. Furthermore, the scavenging activity of 0.60 g/L wheat germ protein hydrolysates against superoxide radical is 75.40%; 0.50 g/L wheat germ protein hydrolysates exhibit 63.35% chelating effect on ferrous ion. These antioxidant activities of wheat germ protein hydrolsates increase with the increase of its concentration. Experimental results suggest that wheat germ protein hydrolysate is a suitable natural antioxidant rich in nutrition and nontoxic.