Coriolus versicolor Mushroom Grown on Selenium-Rich Zeolite Tuff as a Potential Novel Food Supplement

Research background. In the recent years, considerable attention has been given to selenium (Se) status since its deficiency is linked with various disorders and affects at least 13 % of world population. Additionally, mushrooms are known to possess pronounced capacity for absorption of various micronutrients, including Se, from soil/substrate. Here, the possibility of using Se-rich zeolite tuff as a supplement for production of selenized mushroom is investigated. Further, the impact of enrichment on the activity of antioxidant enzymes and biological potential of Coriolus versicolor medicinal mushroom is studied. Experimental approach. Se(IV)- and Se(VI)-modified natural zeolitic tuff from the Serbian deposit Zlatokop was used as substrate supplement in mushroom cultivation. To examine effectiveness of selenium enrichment, beside inductively coupled plasma mass spectrometry (ICP-MS) analysis of total selenium content, determination of antioxidant enzymes in fresh fruiting bodies as well as testing of biological potential of methanol extracts was done. Antioxidant activity was evaluated using tests pertaining to different ways of antioxidant action: inhibition of lipid peroxidation, DPPH free radical scavenging assay, ferric-reducing antioxidant power assay and chelating ability on ferrous ions. The antibacterial activity against foodborne pathogens was measured by broth microdilution assay. Additionally, chemical composition of prepared extracts was studied using UV-Vis and FTIR spectroscopy analyses. Results and conclusions. Content of selenium detected in biofortified C. versicolor was even 470 times higher compared to control ((140.7±3.8) vs (0.3±0.1) µg/g dry mass), proving that Se-rich zeolite tuff is excellent supplement for mushroom production. Further, the results of monitoring the activity of antioxidant enzymes revealed that most of the Se-enriched mushrooms exhibited higher superoxide dismutase (SOD) and catalase (CAT) and lower glutathione peroxidase (GSH-Px) activity than control. Due to elevated level of enzymes, selenated mushrooms could quickly respond to superoxide radicals, formed as a result of detachment, and thus presumably preserve quality for a longer period of time. Investigation of biological potential indicated that Se-enriched mushroom methanol extracts, generally, expressed enhanced antioxidant properties. Additionally, extracts asserted antibacterial activity against all tested pathogenic microorganisms. Novelty and scientific contribution. Cultivation of mushrooms on Se-enriched zeolite tuff is a new technological approach for obtaining Se-fortified food/supplements with enhanced antioxidant and antibacterial activity.

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Effect of Parinari curatellifolia Peel Flour on the Nutritional, Physical and Antioxidant Properties of Biscuits

Processes ◽

10.3390/pr9081262 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1262

Author(s):

Shonisani Eugenia Ramashia ◽

Felicia Matshepho Mamadisa ◽

Mpho Edward Mashau

Keyword(s):

Antioxidant Activity ◽

Antioxidant Properties ◽

Polyphenolic Compounds ◽

Total Phenolic ◽

Crude Fibre ◽

Yellowness Index ◽

Antioxidant Power ◽

Parinari Curatellifolia ◽

Ferric Reducing Antioxidant Power ◽

The Impact

This study investigated the impact of Parinari curatellifolia peel flour on the nutritional, physical and antioxidant properties of formulated biscuits. Biscuits enriched with 5%, 10%, 15% and 20% of Parinari (P). curatellifolia peel flour were formulated and characterised. Thermal, physicochemical, polyphenolic compounds and antioxidant properties of flour and biscuits were determined. The incorporation of P. curatellifolia peel flour significantly increased (p < 0.05) thermal properties (onset, peak and conclusion temperatures) of flour. However, enthalpy of gelatinisation, viscosity and pH of flour samples decreased. Nutritional analysis revealed an increase in ash (0.74% to 2.23%) and crude fibre contents (0.39% to 2.95%) along with an increase of P. curatellifolia peel flour levels. Protein content and carbohydrates decreased while moisture content was insignificantly affected by the addition of P. curatellifolia peel flour. The L*, b* values and whiteness index of formulated biscuits decreased while parameter a* value (10.76 to 21.89) and yellowness index (69.84 to 102.71) decreased. Physical properties such as diameter (3.57 mm to 3.97 mm), spread ratio (2.67 to 3.45) and hardness (1188.13 g to 2432.60 g) increased with the inclusion levels of peel flour while weight and thickness decreased. The inclusion of P. curatellifolia improved the polyphenolic compounds and antioxidant activity of biscuits with values of total flavonoids content ranging from 0.028 to 0.104 mg CE/g, total phenolic content increasing from 20.01 mg to 48.51 mg GAE/g, ferric reducing antioxidant power (FRAP) increasing from 108.33 mg to 162.67 mg GAE/g and DPPH (2,2-diphenyl-1-picrylhydrazyl) from 48.70% to 94.72%. These results lead to the recommendation of the utilisation of P. curatellifolia peel flour to enhance the nutritional value, polyphenolic compounds and antioxidant activity of bakery products such as biscuits.

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UHPLC-HESI-OT-MS-MS Biomolecules Profiling, Antioxidant and Antibacterial Activity of the “Orange-Yellow Resin” from Zuccagnia punctata Cav.

Antioxidants ◽

10.3390/antiox9020123 ◽

2020 ◽

Vol 9 (2) ◽

pp. 123 ◽

Cited By ~ 1

Author(s):

Jessica Gómez ◽

Mario J. Simirgiotis ◽

Sofía Manrique ◽

Beatriz Lima ◽

Jorge Bórquez ◽

...

Keyword(s):

Antibacterial Activity ◽

Liquid Chromatography ◽

Metabolite Profiling ◽

Antioxidant Properties ◽

Antibacterial Properties ◽

Ultrahigh Resolution ◽

Antioxidant Power ◽

Orange Yellow ◽

Ms Analysis ◽

Orbitrap Ms

This research was designed to investigate the metabolite profiling, phenolics, and flavonoids content as well as the potential antioxidant and antibacterial, properties of orange-yellow resin from Zuccagnia punctata Cav (ZpRe). Metabolite profiling was obtained by a ultrahigh resolution liquid chromatography orbitrap MS analysis (UHPLC-ESI-OT-MS-MS). The antioxidant properties were screened by four methods: 2,2-diphenyl-1-picrylhydrazyl assay (DPPH), trolox equivalent antioxidant activity assay (TEAC), ferric-reducing antioxidant power assay (FRAP), and lipid peroxidation in erythrocytes (LP)). The antibacterial activity was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) rules. The resin displayed a strong DPPH scavenging activity (IC50 = 25.72 µg/mL) and showed a percentage of inhibition of LP close to that of the reference compound catechin (70% at 100 µg ZpRe/mL), while a moderated effect was observed in the FRAP and TEAC assays. The resin showed a content of phenolic and flavonoid compounds of 391 mg GAE/g and 313 mg EQ/g respectively. Fifty phenolics compounds were identified by ultrahigh resolution liquid chromatography orbitrap MS analysis (UHPLC-PDA-OT-MS) analysis. Thirty-one compounds are reported for the first time, updating the knowledge on the chemical profile of this species. The importance of the biomolecules identified support traditional use of this endemic plant. Furthermore, additional pharmacological data is presented that increase the potential interest of this plant for industrial sustainable applications.

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Kinetic Behaviour of Skin Pigmentation Inhibitory Activity of some Selected Nigerian Medicinal Plants and Other Related Antioxidant Properties

The Natural Products Journal ◽

10.2174/2210315508666180828101159 ◽

2019 ◽

Vol 9 (4) ◽

pp. 280-288

Author(s):

Olugbenga K. Popoola ◽

Francis J. Faleye ◽

Folorunso A. Olabiyi ◽

Olajide Ayodele

Keyword(s):

Lipid Peroxidation ◽

Medicinal Plants ◽

Skin Pigmentation ◽

Antioxidant Properties ◽

Scientific Data ◽

Order Kinetic ◽

Ageratum Conyzoides ◽

Antioxidant Power ◽

Methanol Extracts ◽

Microsomal Lipid Peroxidation

Background: Over exposure to Ultra Violet (UV) radiation is one of the most significant external stress-inducing factors resulting into occurrence of skin pigmentation among others in human body. The biological implication of such disorders is not only limited to premature skin aging and cancer, but also resulted into economic loss of perishable agricultural products. Methods: Methanol extracts of ten (10) medicinal plants with skin health traditional history were selected for this study. The biological profile of the extracts was assessed in an in-vitro system using colorimetric assays: tyrosinase inhibition, Ferric-ion Reducing Antioxidant Power (FRAP), Trolox Equivalent Absorbance Capacity (TEAC) and Fe II-induced microsomal lipid peroxidation. Results: Representative of asteraceae such as Laggera pterodonta (S3); Ageratum conyzoides (S4) and Chromolaena odorata (S5), while Euphorbia convoluloides (S8) were found to possess good anti- tyrosinase activity (IC50 = 177.50; 125.08; 167.58; 161.92) μg/ml respectively, in which the rate of formation of dopachrome proceeded via pseudo second order kinetic using the Largergren model. Other notable inhibition of oxidative stress displayed by the methanol extracts includes S7 (FRAP = 1905.12 ± 2.85 µM AAE/g); S1 & S6 (TEAC = 2163.48 ± 2.80; 1044.35 ± 28.99) µM TE/g, while S7 & S9 showed highest inhibitory activities on Fe II-induced microsomal lipid peroxidation (IC50 = 33.625; 35.125) µg/ml, respectively in competitive manner to that of the commercial anti-oxidant EGCG (IC50 = 36.250 µg/ml). Conclusion: The outcome of the biological properties of the selected plant extracts in this study suggested the existence of relationship between the traditional claims and the scientific data therein.

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The Combination of Mild Salinity Conditions and Exogenously Applied Phenolics Modulates Functional Traits in Lettuce

Plants ◽

10.3390/plants10071457 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1457

Author(s):

Leilei Zhang ◽

Erika Martinelli ◽

Biancamaria Senizza ◽

Begoña Miras-Moreno ◽

Evren Yildiztugay ◽

...

Keyword(s):

Functional Traits ◽

Inhibitory Activity ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Stress Conditions ◽

Future Application ◽

Total Phenolic ◽

Phenolic Profile ◽

Antioxidant Power ◽

The Impact

The quest for sustainable strategies aimed at increasing the bioactive properties of plant-based foods has grown quickly. In this work, we investigated the impact of exogenously applied phenolics, i.e., chlorogenic acid (CGA), hesperidin (HES), and their combinations (HES + CGA), on Lactuca sativa L. grown under normal- and mild-salinity conditions. To this aim, the phenolic profile, antioxidant properties, and enzyme inhibitory activity were determined. The untargeted metabolomics profiling revealed that lettuce treated with CGA under non-stressed conditions exhibited the highest total phenolic content (35.98 mg Eq./g). Lettuce samples grown under salt stress showed lower phenolic contents, except for lettuce treated with HES or HES + CGA, when comparing the same treatment between the two conditions. Furthermore, the antioxidant capacity was investigated through DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,20-azinobis-(3-ethylbenzothiazoline-6-sulfonate)), and FRAP (ferric reducing antioxidant power) assays, coupled with metal-chelating activity and phosphomolybdenum capacity. An exciting increase in radical scavenging capacity was observed in lettuce treated with exogenous phenolics, in both stress and non-stress conditions. The inhibitory activity of the samples was evaluated against target health-related enzymes, namely cholinesterases (acetylcholinesterase; AChE; butyryl cholinesterase; BChE), tyrosinase, α-amylase, and α-glucosidase. Lettuce treated with HES + CGA under non-stress conditions exhibited the strongest inhibition against AChE and BChE, while the same treatment under salinity conditions resulted in the highest inhibition capacity against α-amylase. Additionally, CGA under non-stress conditions exhibited the best inhibitory effect against tyrosinase. All the functional traits investigated were significantly modulated by exogenous phenolics, salinity, and their combination. In more detail, flavonoids, lignans, and stilbenes were the most affected phenolics, whereas glycosidase enzymes and tyrosinase activity were the most affected among enzyme assays. In conclusion, the exogenous application of phenolics to lettuce represents an effective and green strategy to effectively modulate the phenolic profile, antioxidant activity, and enzyme inhibitory effects in lettuce, deserving future application to produce functional plant-based foods in a sustainable way.

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Influence of different commercial fining agents on proanthocyanidin fraction and antioxidant activity of a red wine from Baga grapes

OENO One ◽

10.20870/oeno-one.2009.43.2.802 ◽

2009 ◽

Vol 43 (2) ◽

pp. 111

Author(s):

Fernando Jorge Gonçalves ◽

António Manuel Jordão

Keyword(s):

Antioxidant Activity ◽

Red Wine ◽

Antioxidant Properties ◽

Human Organism ◽

Red Wines ◽

Antioxidant Power ◽

Egg Albumin ◽

Degree Of Polymerisation ◽

Fining Agents ◽

The Impact

Aims: Evaluate the impact of different commercial fining agents (egg albumin, bentonite, gelatine, potassium caseinate and isinglass) and their concentration on proanthocyanidin fraction content (monomeric, oligomeric and polymeric) and antioxidant activity of a red wine from Baga grape variety. Additionally establishment of correlations between the antioxidant activity and the different proanthocyanidin fraction content were also an other aim of this work.Methods and results: The fractionation of wine proanthocyanidins was made according to their polymerisation degree: catechins (monomers), oligomeric (degree of polymerisation ranging from 2 to 12-15) and polymeric (degree of polymerisation > 12-15). For antioxidant activity of red wine, two analytical methods were used: the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and the ABTS radical cation scavenging assay. In general the different commercial fining agents applied induced a decrease of the wine total phenols and the different proanthocyanidin fraction content studied. The monomeric flavanols were significantly depleted by egg albumin and isinglass (specially using the highest concentration), while for oligomeric fraction only the highest egg albumin, gelatine and isinglass concentration induced a decrease on the values.Conclusion: The commercial fining agents analyzed in the present study affected the monomeric and the oligomeric proanthocyanidin. At same time some fining agents (specially in high concentrations), such as egg albumin, isinglass and gelatine induced a reduction of antioxidant activity of red wines too.Significant and impact study: The knowledge of the impact of the commercial fining agents in proanthocyanidin content and antioxidant properties of red wines is important for red wine fining optimisation and consequently for the red wine quality. This study is particular important when the « antioxidant power » of the foods, in this case in red wine, is an expression of its capability both to defend the human organism from the action of the free radicals and to prevent degenerative disorders deriving from persistent oxidative stress.

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Ameliorated Antibacterial and Antioxidant Properties by Trichoderma harzianum Mediated Green Synthesis of Silver Nanoparticles

Biomolecules ◽

10.3390/biom11040535 ◽

2021 ◽

Vol 11 (4) ◽

pp. 535

Author(s):

Narasimhamurthy Konappa ◽

Arakere C. Udayashankar ◽

Nirmaladevi Dhamodaran ◽

Soumya Krishnamurthy ◽

Shubha Jagannath ◽

...

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Trichoderma Harzianum ◽

Antioxidant Properties ◽

Xrd Analysis ◽

Bioactive Metabolites ◽

Infrared Spectrometry ◽

Frap Assay ◽

Antioxidant Power ◽

Average Size

Biosynthesis of silver nanoparticles using beneficial Trichoderma harzianum is a simple, eco-friendly and cost-effective route. Secondary metabolites secreted by T. harzianum act as capping and reducing agents that can offer constancy and can contribute to biological activity. The present study aimed to synthesize silver nanoparticles using T. harzianum cell filtrate and investigate different bioactive metabolites based on LC-MS/MS analysis. The synthesized silver nanoparticles (AgNPs) from T. harzianum were characterized by ultraviolet–visible spectrophotometry, Fourier transform infrared spectrometry (FT-IR), energy-dispersive spectroscopy (EDS), dynamic light scattering (DLS), X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The surface plasmon resonance of synthesized particles formed a peak centered near 438 nm. The DLS study determined the average size of AgNPs to be 21.49 nm. The average size of AgNPs was measured to be 72 nm by SEM. The cubic crystal structure from XRD analysis confirmed the synthesized particles as silver nanoparticles. The AgNPs exhibited remarkable antioxidant properties, as determined by DPPH and ferric reducing antioxidant power (FRAP) assay. The AgNPs also exhibited broad-spectrum antibacterial activity against two Gram-positive bacteria (S. aureus and B. subtilis) and two Gram-negative bacteria (E. coli and R. solanacearum). The minimum inhibitory concentration (MIC) of AgNPs towards bacterial growth was evaluated. The antibacterial activity of AgNPs was further confirmed by fluorescence microscopy and SEM analysis.

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Antioxidant properties and sensory attributes of blends prepared from standardized milk and soy milk

Nutrition & Food Science ◽

10.1108/nfs-05-2019-0150 ◽

2019 ◽

Vol 50 (4) ◽

pp. 679-693

Author(s):

Devendra Pratap ◽

Kumaresh Halder ◽

Rakhi Singh ◽

Ankur Ojha ◽

Thangalakshmi S. ◽

...

Keyword(s):

Milk Sample ◽

Antioxidant Activities ◽

Antioxidant Properties ◽

Fuzzy Modeling ◽

Sensory Attributes ◽

Soy Milk ◽

Antioxidant Power ◽

Content Type ◽

Control Milk ◽

The Impact

Purpose Although milk is considered a vital source of nutrition for the livelihood, as the beginning of civilization, its antioxidant potential is required to be improved. This paper aims to increase antioxidant activities in milk and soy milk (Glycine max L.) has been found as a good compatible source. Hence, the present work was planned to investigate the impact of blending of different proportions of soy milk with standardized milk (i.e. 50 per cent soy milk with 50 per cent standardized milk, 60 per cent soy milk with 40 per cent standardized milk, 70 per cent soy milk with 30 per cent standardized milk and 100 per cent standardized milk as control sample) on antioxidant properties and sensory attributes of the blends. Design/methodology/approach Antioxidant properties of the blends were determined in terms of 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power and total phenol content. Sensory evaluation was carried out using a nine-point hedonic scale based on four selected quality attributes (i.e. smell, taste, color and appearance and mouthfeel) and ranked for their quality traits by fuzzy modeling. Findings A blend containing 70 per cent soy milk with 30 per cent standardized milk showed the highest antioxidant activities as compared to control milk sample (p < 0.05). Blend of 50 per cent soy milk with 50 per cent standardized milk was found most acceptable on the basis of sensory analysis and its antioxidant activities were also appreciable as compared to control milk sample (p < 0.05). Smell, taste, color and appearance and mouthfeel influenced the acceptability of formulated milk samples in decreasing order of significance (p < 0.05). Originality/value The present attempt has been made to formulate liquid milk by mixing standardized milk and soy milk, in which enhancement in the antioxidant activities of standardized milk and masking of off-flavor of soy milk is done. It is not done before and it may improve the nutritional and commercial value of the milk. Further, fuzzy modeling used for choosing appropriate blend in terms of sensory scores is also found as a novel approach.

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Phenolic Composition and Biological Properties of Wild and Commercial Dog Rose Fruits and Leaves

Molecules ◽

10.3390/molecules25225272 ◽

2020 ◽

Vol 25 (22) ◽

pp. 5272

Author(s):

Milena Polumackanycz ◽

Mateusz Kaszuba ◽

Agnieszka Konopacka ◽

Urszula Marzec-Wróblewska ◽

Marek Wesolowski ◽

...

Keyword(s):

Antibacterial Activity ◽

Phenolic Compounds ◽

Antioxidant Properties ◽

Rich Source ◽

Total Phenolic ◽

Phenolic Composition ◽

Antioxidant Power ◽

Phenolic Constituents ◽

Dog Rose

Rosa canina L. (dog rose) is a rich source of phenolic compounds that offer great hope for the prevention of chronic human diseases. Herein, wild and commercial samples of dog rose were chemically characterized with respect to their phenolic composition by liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI/MS). Furthermore, in vitro antioxidant properties and antibacterial activity of dog rose fruits and leaves hydromethanolic extracts and infusions were also evaluated. The results revealed that wild and commercial fruits of dog rose are similar in terms of l(+)-ascorbic acid, total phenolics (TPC), total flavonoids (TFC) and total phenolic acids (TPAC) content, individual phenolic constituents and antioxidant activity. Moreover, the fruits had lower levels of phenolic compounds and also revealed lower biological activity than the leaves. On the other hands, the highest content of TPC, TFC, TPAC, individual phenolic constituents, DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity and FRAP (ferric reducing antioxidant power) were found in the leaf’s infusions. They were also the only ones to show antibacterial activity. Overall, these finding confirmed usefulness of R. canina L. leaves and fruits as a rich source of bioactive phenolic compounds with potential use in food, pharmaceutical, and cosmetic industries.

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Edible Flowers Extracts as a Source of Bioactive Compounds with Antioxidant Properties—In Vitro Studies

Applied Sciences ◽

10.3390/app11052120 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2120

Author(s):

Karolina Jakubczyk ◽

Agnieszka Łukomska ◽

Izabela Gutowska ◽

Joanna Kochman ◽

Joanna Janił ◽

...

Keyword(s):

Oxidative Stress ◽

Antioxidant Enzymes ◽

White Clover ◽

Trifolium Repens ◽

Trifolium Pratense ◽

Antioxidant Properties ◽

Red Clover ◽

Total Content ◽

Antioxidant Potential ◽

Antioxidant Power

Edible plants began to play an important role in past decade as a part of therapy, a recovery process or a healthy life style. The availability and relatively low price of the raw material, as well as proven bioactive health benefits, are key to consumers’ choice of nutrients. The red clover (Trifolium pratense) is a popular plant with healthy properties such as antiseptic and analgesic effects. The less known white clover (Trifolium repens), a fodder and honey plant, has anti-rheumatic and anti-diabetic properties. Both species may serve as a potential source of bioactive substances with antioxidant properties as a food additive or supplement. The study material consisted of flower extracts of Trifolium repens and Trifolium pratense. The total content of polyphenols and DPPH (2.2-diphenyl-1-picrylhydrazyl) and ferric reducing antioxidant power (FRAP) were measured using spectrophotometry methods. Oxidative stress in THP1 cells was induced via sodium fluoride. Subsequently, flower extracts were added and their influences on proliferation, antioxidant potential and the activity of antioxidant enzymes were evaluated. The extracts have a high total content of polyphenols as well as high antioxidant potential. We also demonstrated positive extracts impact on cells proliferation, high antioxidant potential and increasing activity of antioxidant enzymes on cell cultures under high oxidative stress induced by fluoride. Both red clover and the less known white clover may serve as valuable sources of antioxidants in the everyday diet.

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Blanching Pre-Treatment Promotes High Yields, Bioactive Compounds, Antioxidants, Enzyme Inactivation and Antibacterial Activity of ‘Wonderful’ Pomegranate Peel Extracts at Three Different Harvest Maturities

Antioxidants ◽

10.3390/antiox10071119 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1119

Author(s):

Tandokazi Pamela Magangana ◽

Nokwanda P. Makunga ◽

Chris la Grange ◽

Maria A. Stander ◽

Olaniyi Amos Fawole ◽

...

Keyword(s):

Antibacterial Activity ◽

Antioxidant Properties ◽

Value Added ◽

Enzyme Inactivation ◽

Total Phenolic ◽

Klebsiella Pneumonia ◽

Pomegranate Peel ◽

Antioxidant Power ◽

Wide Range ◽

Pre Treatment

‘Wonderful’ pomegranate (Punica granatum L.) peel contains a wide range of phytochemicals including vitamins, dietary fibre, phenolic compounds, and antioxidant properties. Yet, it is often used as animal feed or discarded in landfills, which is not the best eco-friendly way to utilize this phenolic-rich bioresource. Finding novel ways of utilizing pomegranate peel waste could prove a more profitable and eco-friendlier alternative that is far more beneficial to the economy. Adding a blanching pre-treatment step at optimal conditions prior to processing of pomegranate peel aids in the inactivation of quality changing enzymes such as polyphenol oxidase (PPO) and peroxidase (POD), which are accountable for the degradation reactions that cause breakdown of nutrients and phytochemicals. This study aimed to determine the effect of blanching at 80 °C for 3 min on the yield, polyphenol content, antioxidant properties, enzyme inactivation, and antibacterial activity of ‘Wonderful’ pomegranate peel ethanolic extracts from three different harvest maturities (unripe, ripe, and over ripe), including a comprehensive characterization and quantification using liquid chromatography-mass spectrometry (LC-MS). The blanched unripe peel extracts exhibited the highest total phenolic content, total tannin content, 2,2-diphenyl-1-picryl hydrazyl (DPPH) antioxidant activity, 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity and ferric ion reducing antioxidant power (FRAP) at 14.0 mg gallic acid equivalent (GAE)/g dry mass (DM), 1.0 mg GAE/g DM, 359.1 µmol Trolox/g DM, 912.2 µmol Trolox/g DM and 802.5 µmol Trolox/g DM, respectively. There was significant (p < 0.05) decrease in PPO and POD activity of all blanched pomegranate peel extracts. The blanched unripe peel extracts had the lowest PPO activity at 0.2 U/g fresh weight (FW), with a 70% PPO inactivation compared to ripe and over ripe harvest, whereas the highest POD inactivation was recorded at 67% in over ripe peel extracts. All blanched peel extracts, irrespective of harvest maturity, had minimum inhibitory concentration (MIC) values at 160 µg/mL against all four bacteria strains tested, which included two Gram-positive bacterial strains (Bacillus subtilis ATCC 6051 and Staphylococcus aureus ATCC 12600) and two Gram-negative bacteria (Escherichia coli 11775 and Klebsiella pneumonia ATCC 13883). A total of 25 metabolites including phenolic acids (4), organic acids (1), flavonoids (4), ellagitannins (13), and other polyphenols (3) in all three pomegranate peel samples were tentatively identified after LC-MS profiling. The blanched unripe peel extracts showed significantly higher punicalin α and β, β punicalagin, catechin, epicatechin content at 414 mg/g, and 678 mg/g, 151 mg/g, 229 mg/g, respectively, compared to peel extracts from other harvest maturities. This study provides supportive information for the commercial utilization of pomegranate fruit peel as source of value-added ingredients for the development of novel food, cosmetics, and pharmacological products.

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