scholarly journals Purification, Characterization, and Application for Preparation of Antioxidant Peptides of Extracellular Protease from Pseudoalteromonas sp. H2

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3373
Author(s):  
Dan Liu ◽  
Jiafeng Huang ◽  
Cuiling Wu ◽  
Congling Liu ◽  
Ran Huang ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Porcine Skin ◽  
Hydrolysis Time ◽  
Skin Collagen ◽  
Wide Ph Range ◽  
The Stability ◽  
Ph Range ◽  
Collagen Hydrolysates

The study reported on the isolation of a metalloprotease named EH2 from Pseudoalteromonas sp. H2. EH2 maintained more than 80% activity over a wide pH range of 5–10, and the stability was also nearly independent of pH. Over 65% activity was detected at a wide temperature range of 20–70 °C. The high stability of the protease in the presence of different surfactants and oxidizing agents was also observed. Moreover, we also investigated the antioxidant activities of the hydrolysates generated from porcine and salmon skin collagen by EH2. The results showed that salmon skin collagen hydrolysates demonstrated higher DPPH (1,1-diphenyl-2-picrylhydrazyl) (42.88% ± 1.85) and hydroxyl radical (61.83% ± 3.05) scavenging activity than porcine skin collagen. For oxygen radical absorbance capacity, the hydrolysates from porcine skin collagen had higher efficiency (7.72 ± 0.13 μmol·TE/μmol). Even 1 nM mixed peptides could effectively reduce the levels of intracellular reactive oxygen species. The two types of substrates exerted the best antioxidant activity when hydrolyzed for 3 h. The hydrolysis time and type of substrate exerted important effects on the antioxidant properties of hydrolysates. The hydrolyzed peptides from meat collagens by proteases have good antioxidant activity, which may have implications for the potential application of marine proteases in the biocatalysis industry.

scholarly journals Antioxidant properties, quantification and stability of betalains from pitaya (Hylocereus undatus) peel

2014 ◽  
Vol 45 (2) ◽  
pp. 323-328 ◽  
Author(s):  
Fernanda Robert de Mello ◽  
Claudia Bernardo ◽  
Caroline Odebrecht Dias ◽  
Luciano Gonzaga ◽  
Edna Regina Amante ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Phenolic Compounds ◽  
Antioxidant Properties ◽  
Raw Material ◽  
High Concentration ◽  
Natural Colorant ◽  
Wide Ph Range ◽  
Hylocereus Undatus ◽  
Ph Range ◽  
Promising Source

Pitaya peel can be used as a raw material for betalains extraction. The aim of this research was to quantify phenolic compounds, antioxidant activity and betalains on pitaya peel. Furthermore, evaluate the betalains stability against various pH conditions and exposure time of heating. The results showed that pitaya peel contains phenolic compounds and presented antioxidant activity. Moreover it showed high concentration of betalains (101.04mg equivalent to betanin. 100g-1) which were stable over a wide pH range (3.2 - 7.0) and were resistant to heating (100oC) up to 10 minutes at pH range from 3.7 to 5.5. Therefore, pitaya peel is a promising source of betalains which can be applied as a natural colorant for food.

Thermal and acido-basic stability of antioxidant properties of extracts from cereal and pseudocereal grains

Biologia ◽  
2013 ◽  
Vol 68 (1) ◽  
Author(s):  
Tibor Maliar ◽  
Mária Maliarová ◽  
Ján Kraic ◽  
Miroslav Ondrejovič ◽  
Ivana Pšenáková ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Raw Material ◽  
Antioxidant Power ◽  
Beneficial Effects ◽  
Barley Cultivars ◽  
Ferric Reducing Antioxidant Power ◽  
The Stability ◽  
High Level

AbstractBeneficial effects of whole grains of cereals and pseudocereals and their fractions to human physiology are well known and broadly published. Especially secondary metabolites, dominantly from the category of phenolics (or polyphenols), beneficially influence the health physiology and/or prevent disease progress. Within the frame of this study, ten genotypes of four cereals or pseudocereals, respectively, were chosen for their antioxidant activity, determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and β-carotene-linoleic acid bleaching model (BCLM) mechanisms. Tested genotypes were selected from primary collection based on their antioxidant activity values, as well as higher level of flavonoids or phenolic acids. The stability of antioxidant properties after thermic, acidic, and basic treatments was evaluated. The oat cultivar Sirene and buckwheat cultivar Bogatyr expressed high level of the antioxidant activity, but they lost it due to all types of treatment. Oppositely, treatments increased antioxidant activities in some samples, especially in oat cultivar Maris Oberon, wheat cultivar Ines and Karolinum, or partially in barley cultivars Kompakt (after basic treatment) and Jubilant (acidic and basic treatments). The lack of the antioxidant activity could be observed due to destruction of the key compounds responsible for the antioxidant effect, whereas the increasing activity could be seen due to release of the aglycons from glycosidic forms after treatment. The stability of antioxidant properties could be a valuable parameter of the raw material for manufacturing special foods with functional properties.

Antioxidant activity of cookiessupplemented with sugarbeet dietary fiber

2011 ◽  
pp. 151-157 ◽  
Author(s):  
Marijana B. Saka ◽  
Julianna F. Gyura ◽  
Aleksandra Mišan ◽  
Zita I. Šereš ◽  
Biljana S. Pajin ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Shelf Life ◽  
Dietary Fiber ◽  
Wheat Flour ◽  
Room Temperature ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Functional Characteristics

The antioxidant activity of cookies prepared by the addition of sugarbeet dietary fibers was investigated in order to estimate their influence on functional characteristics and shelf-life of cookies. Treated fiber (TF) was obtained from sugarbeet by extraction with sulfurous acid (75 °C at pH = 5.7during 60 min) and treatment with hydrogen peroxide (20 g/LH2O2 at pH = 11 during 24 h). The fiber obtained was dried (80 °C), ground and sieved. TF was investigated in comparison with commercially available Fibrex®. The cookies were prepared by the addition of 0, 7, 9 and 11% of sugarbeet dietary fiber as a substitute for wheat flour in the formulation of cookies. The antioxidant properties of cookies were tested every 7 days using a DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity test during 6 weeks of storage at room temperature (23 ± 1 ºC). The obtained results indicated that substitution of wheat flour with Fibrex® in the formulation of cookies upgraded the antioxidant activity, i.e. the functional characteristics of Fibrex®-enriched cookies and could prolong their shelf-life. In contrast, TF did not increase the antioxidant activity of TF-enriched cookies. The better antioxidant activities of Fibrex®-enriched cookies could be attributed to the presence of ferulic acid.

scholarly journals Effect of particle size on phytochemical composition and antioxidant properties of Sargassum cristaefolium ethanol extract

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
E. S. Prasedya ◽  
A. Frediansyah ◽  
N. W. R. Martyasari ◽  
B. K. Ilhami ◽  
A. S. Abidin ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Particle Size ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Ethanol Extract ◽  
Total Phenolic ◽  
Particle Sizes ◽  
Epicatechin Gallate ◽  
Particle Size Reduction ◽  
Phytochemical Composition

AbstractSample particle size is an important parameter in the solid–liquid extraction system of natural products for obtaining their bioactive compounds. This study evaluates the effect of sample particle size on the phytochemical composition and antioxidant activity of brown macroalgae Sargassum cristaefolium. The crude ethanol extract was extracted from dried powders of S.cristeafolium with various particle sizes (> 4000 µm, > 250 µm, > 125 µm, > 45 µm, and < 45 µm). The ethanolic extracts of S.cristaefolium were analysed for Total Phenolic Content (TPC), Total Flavonoid Content (TFC), phenolic compound concentration and antioxidant activities. The extract yield and phytochemical composition were more abundant in smaller particle sizes. Furthermore, the TPC (14.19 ± 2.08 mg GAE/g extract to 43.27 ± 2.56 mg GAE/g extract) and TFC (9.6 ± 1.8 mg QE/g extract to 70.27 ± 3.59 mg QE/g extract) values also significantly increased as particle sizes decreased. In addition, phenolic compounds epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC), and Epigallocatechin gallate (EGCG) concentration were frequently increased in samples of smaller particle sizes based on two-way ANOVA and Tukey’s multiple comparison analysis. These results correlate with the significantly stronger antioxidant activity in samples with smaller particle sizes. The smallest particle size (< 45 µm) demonstrated the strongest antioxidant activity based on DPPH, ABTS, hydroxyl assay and FRAP. In addition, ramp function graph evaluates the desired particle size for maximum phytochemical composition and antioxidant activity is 44 µm. In conclusion, current results show the importance of particle size reduction of macroalgae samples to increase the effectivity of its biological activity.

scholarly journals Synthesis, Neuroprotection, and Antioxidant Activity of 1,1′-Biphenylnitrones as α-Phenyl-N-tert-butylnitrone Analogues in In Vitro Ischemia Models

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1127 ◽  
Author(s):  
Beatriz Chamorro ◽  
David García-Vieira ◽  
Daniel Diez-Iriepa ◽  
Estíbaliz Garagarza ◽  
Mourad Chioua ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Glucose Deprivation ◽  
Oxygen Glucose Deprivation ◽  
Human Neuroblastoma ◽  
In Vitro Ischemia ◽  
Lipoxygenase Inhibition ◽  
Antioxidant Agent

Herein, we report the neuroprotective and antioxidant activity of 1,1′-biphenyl nitrones (BPNs) 1–5 as α-phenyl-N-tert-butylnitrone analogues prepared from commercially available [1,1′-biphenyl]-4-carbaldehyde and [1,1′-biphenyl]-4,4′-dicarbaldehyde. The neuroprotection of BPNs1-5 has been measured against oligomycin A/rotenone and in an oxygen–glucose deprivation in vitro ischemia model in human neuroblastoma SH-SY5Y cells. Our results indicate that BPNs 1–5 have better neuroprotective and antioxidant properties than α-phenyl-N-tert-butylnitrone (PBN), and they are quite similar to N-acetyl-L-cysteine (NAC), which is a well-known antioxidant agent. Among the nitrones studied, homo-bis-nitrone BPHBN5, bearing two N-tert-Bu radicals at the nitrone motif, has the best neuroprotective capacity (EC50 = 13.16 ± 1.65 and 25.5 ± 3.93 μM, against the reduction in metabolic activity induced by respiratory chain blockers and oxygen–glucose deprivation in an in vitro ischemia model, respectively) as well as anti-necrotic, anti-apoptotic, and antioxidant activities (EC50 = 11.2 ± 3.94 μM), which were measured by its capacity to reduce superoxide production in human neuroblastoma SH-SY5Y cell cultures, followed by mononitrone BPMN3, with one N-Bn radical, and BPMN2, with only one N-tert-Bu substituent. The antioxidant activity of BPNs1-5 has also been analyzed for their capacity to scavenge hydroxyl free radicals (82% at 100 μM), lipoxygenase inhibition, and the inhibition of lipid peroxidation (68% at 100 μM). Results showed that although the number of nitrone groups improves the neuroprotection profile of these BPNs, the final effect is also dependent on the substitutent that is being incorporated. Thus, BPNs bearing N-tert-Bu and N-Bn groups show better neuroprotective and antioxidant properties than those substituted with Me. All these results led us to propose homo-bis-nitrone BPHBN5 as the most balanced and interesting nitrone based on its neuroprotective capacity in different neuronal models of oxidative stress and in vitro ischemia as well as its antioxidant activity.

Effects of Enzyme Types and Extraction Conditions on Protein Recovery and Antioxidant Properties of Hydrolysed Proteins Derived from Defatted Lemna minor

2021 ◽  
Author(s):  
Hai Chi Tran ◽  
Hong Anh Thi Le ◽  
Thanh Thanh Le ◽  
Van Man Phan
Keyword(s):  
Enzymatic Hydrolysis ◽  
Antioxidant Activities ◽  
Lemna Minor ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Good Method ◽  
Alkaline Treatment ◽  
Protein Recovery ◽  
Hydrolysis Time ◽  
Hydrolysis Degree

Lemna minor (L. minor), the common duckweed, contains a high protein substance and is considered as a good source of potential bioactive peptides. The objective of this study is to investigate the effect of enzymatic hydrolysis times (60–180 min) and enzyme concentrations (0.5–3.5%v/w) with Alcalase and Flavourzyme on the recovery, hydrolysis degree (DH), and antioxidant properties of peptides derived from defatted L. minor. The protein recovery, hydrolysis degree (DH), and antioxidant activities obtained by enzymatic were compared with the alkaline treatment method. The results showed that the protein recovery, DH values, and antioxidant activities were enhanced by increasing the enzyme concentration and hydrolysis time. Specifically, the recovery of protein and DH values reached the highest level after the enzymatic hydrolysis by Flavourzyme or Alcalase at 1.5 v/w enzyme for 120 min. At the same enzymatic hydrolysis condition, the samples hydrolyzed by Flavourzyme had a higher inhibitory effect on the ABTS•+ and DPPH•+ radical scavenging than those hydrolyzed by Alcalase and the alkaline treatment. Further study also showed that the DH values, amino acid contents, and antioxidant activities of the protein extracts were positively correlated. Thus, the extractions with Flavourzyme and Alcalse were a good method to produce a significant amount of amino acids and smaller peptides.

scholarly journals The Bioactivity Prediction of Peptides from Tuna Skin Collagen Using Integrated Method Combining In Vitro and In Silico

Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2739
Author(s):  
Liza Devita ◽  
Hanifah Nuryani Lioe ◽  
Mala Nurilmala ◽  
Maggy T. Suhartono
Keyword(s):  
Antioxidant Activity ◽  
In Silico ◽  
Antioxidant Activities ◽  
In Silico Analysis ◽  
Weight Fraction ◽  
Amino Acid Sequences ◽  
Skin Collagen ◽  
Dpph Method ◽  
Peptide Fractions

The hydrolysates and peptide fractions of bigeye tuna (Thunnus obesus) skin collagen have been successfully studied. The hydrolysates (HPA, HPN, HPS, HBA, HBN, HBS) were the result of the hydrolysis of collagen using alcalase, neutrase, and savinase. The peptide fractions (PPA, PPN, PPS, PBA, PBN, PBS) were the fractions obtained following ultrafiltration of the hydrolysates. The antioxidant activities of the hydrolysates and peptide fractions were studied using the DPPH method. The effects of collagen types, enzymes, and molecular sizes on the antioxidant activities were analyzed using profile plots analysis. The amino acid sequences of the peptides in the fraction with the highest antioxidant activity were analyzed using LC-MS/MS. Finally, their bioactivity and characteristics were studied using in silico analysis. The hydrolysates and peptide fractions provided antioxidant activity (6.17–135.40 µmol AAE/g protein). The lower molecular weight fraction had higher antioxidant activity. Collagen from pepsin treatment produced higher activity than that of bromelain treatment. The fraction from collagen hydrolysates by savinase treatment had the highest activity compared to neutrase and alcalase treatments. The peptides in the PBN and PPS fractions of <3 kDa had antidiabetic, antihypertensive and antioxidant activities. In conclusion, they have the potential to be used in food and health applications.

scholarly journals Antioxidant Activities of Extracts from Celery Leaves (Apium Graveolens L) Grown in Jos, Nigeria

2020 ◽  
pp. 1-5
Author(s):  
M. Suleman Stephen ◽  
E. A. Adelakun ◽  
J. H. Kanus ◽  
Meshack M. Gideon
Keyword(s):  
Antioxidant Activity ◽  
Ascorbic Acid ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Ethanolic Extract ◽  
Acetone Extract ◽  
Apium Graveolens ◽  
Isolation And Identification ◽  
Celery Plant

The presence of natural antioxidant in plants is well known. Plant phenolics constitute one of the major groups of components that act as antioxidant and free radical terminator. Hence, this study focused on investigating the antioxidant activity of Celery plant (Apium graveolens L). The fresh leaves were collected, crushed and extracted with ethanol and acetone by maceration. The radical scavenging properties of the extracts were determined by measuring changes in absorbance of DPPH radical at a wave lenght of 517 nm by UV and ascorbic acid is used as the standard. It showed that the crude ethanolic extract has higher antioxidant activity compared to ascorbic acid and acetone extract with less scavenging activity. The values were (IC50 114.6 µg/mL) for ascorbic acid, (IC50 112 µg/mL) for the crude ethanolic extract and (IC50172 µg/mL) for crude acetone extract. The result shows that Celery plant grown in Jos possess good antioxidant properties which may be linked to the presence of phenolics and flavonoids in the plant, which justifies its use as a medicinal plant. This can be further investigated for the isolation and identification of active compounds of medicinal utilities.

Mycochemical composition and antioxidant potential of Macrolepiota africana (Heim) Heinem. (Agaricaceae), an edible mushroom from Gabon

2021 ◽  
Vol 2 (1) ◽  
pp. 028-033
Author(s):  
Hugues Calixte Eyi Ndong ◽  
André Ledoux Njouonkou
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Activity Index ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Edible Mushroom ◽  
Mushroom Species ◽  
Chemical Screening ◽  
Ethanolic Extracts ◽  
Pharmacological Potential

Macrolepiota africana is a fungus used as food in Gabon for its culinary properties. However, its nutritional value, mycochemical contents, antioxidant properties and health potential still unknown. The present study investigated the phytochemicals and antioxidant properties of this mushroom species. This chemical screening was followed by a study of the antioxidant activity and a prediction of additional pharmacological activities of M. africana. Using standard methodology, the mycochemical analyses were carried out on aqueous, hydro-ethanolic and ethanolic fungi extracts. The antioxidant activity of the mushroom extracts was determined using DPPH radical scavenging assay. Apart from Digitoxigenine, flavonol and gitoxigenine that were not found in any of the extracts, all other tested mycochemical were found in atleast one of the extracts. Alkaloids, flavonoids, polyphenols, oses and holosides, proanthocyanidins and coumarins were found in all extracts at different intensity. Saponosids, sterols and triterpenes, tannins gallics, reducing sugar, anthracenosides and digitoxine were found in two extracts while tannins catechics, flavone and gitoxine were detected only in one extract. The dosage of phenolic compounds confirmed the richness of this fungus in total polyphenols, its moderate richness in proanthocyanidins, the lack of flavonoids in the aqueous extract and the moderate richness of the hydro-ethanolic and ethanolic extracts in flavonoids. Regarding the antioxidant activities, the results obtained for the DPPH trapping test showed that the different extracts had low to moderate antioxidant activity with antioxidant activity index (IAA) ranged 0.29 to 0.97 respectively in aqueous and ethanolic extracts. The presence of these mycochemical compounds along with the identified antioxidant activities shows that this M. africana have some pharmacological potential.

Biochemical and Biophysical characterization of the main protease, 3-chymotrypsin-like protease (3CLpro), from the novel coronavirus disease 19 (COVID-19)

2020 ◽  
Author(s):  
Juliana C. Ferreira ◽  
Wael M. Rabeh
Keyword(s):  
Antiviral Drug ◽  
Analytical Techniques ◽  
The Novel ◽  
Buffer Solution ◽  
Biophysical Characterization ◽  
Main Protease ◽  
Wide Ph Range ◽  
The Stability ◽  
Ph Range ◽  
Novel Coronavirus

Abstract Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is responsible for the novel coronavirus disease 2019 (COVID-19). An appealing antiviral drug target is the coronavirus 3C-like protease (3CLpro) that is responsible for the processing of the viral polyproteins and liberation of functional proteins essential for the maturation and infectivity of the virus. In this study, multiple thermal analytical techniques have been implemented to acquire the thermodynamic parameters of 3CLpro at different buffer conditions. 3CLpro exhibited relatively high thermodynamic stabilities over a wide pH range; however, the protease was found to be less stable in the presence of salts. Divalent metal cations reduced the thermodynamic stability of 3CLpro more than monovalent cations; however, altering the ionic strength of the buffer solution did not alter the stability of 3CLpro. Furthermore, the most stable thermal kinetic stability of 3CLpro was recorded at pH 7.5, with the highest enthalpy of activation calculated from the slope of Eyring plot. The biochemical and biophysical properties of 3CLpro explored here will improve the solubility and stability of 3CLpro for optimum conditions for the setup of an enzymatic assay for the screening of inhibitors to be used as lead candidates in the drug discovery and antiviral design for therapeutics against COVID-19.

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