The Influence of Time and Storage Conditions on the Antioxidant Potential and Total Phenolic Content in Homemade Grape Vinegars

Fermented foods have been an integral part of the cuisines of almost all cultures in the world. In recent years, they have gained ground again, mainly due to their potential health benefits. One such product is grape vinegar, which apart from characteristic taste, is also a source of compounds with antioxidant activity. The aim of the study was to determine the changes in the antioxidant potential and the content of polyphenols that occur during the storage of grape vinegar obtained by spontaneous fermentation. The research material consisted of vinegar made from different white grape varieties grown in Poland. For each variety, two variants were prepared: with and without the addition of sugar in the fermentation process. The antioxidant potential, polyphenol content, soluble solids content and pH were monitored both during the two-month fermentation process and the subsequent 6-months storage under various conditions. Storage conditions and time of the storage affected the antioxidant activity and polyphenol content. The content of these compounds was also influenced by the variety of grapes used as well as the method of vinegar preparation.

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Optimal Design Approach Applied to Headspace GC for the Monitoring of Diacetyl Concentration, Spectrophotometric Assessment of Phenolic Compounds and Antioxidant Potential in Different Fermentation Processes of Barley

Applied Sciences ◽

10.3390/app12010037 ◽

2021 ◽

Vol 12 (1) ◽

pp. 37

Author(s):

Fouad El Mansouri ◽

Hammadi El Farissi ◽

Francesco Cacciola ◽

Badr Bouhcain ◽

Joaquim C. G. Esteves da Silva ◽

...

Keyword(s):

Antioxidant Activity ◽

Thermal Process ◽

Fermentation Process ◽

Control Method ◽

Spectrophotometric Analysis ◽

Antioxidant Potential ◽

Total Phenolic ◽

Total Flavonoids ◽

Fermentation Processes ◽

The Impact

The present study aimed to validate a control method on the gas chromatography system (GC) based on the experimental design strategy, to examine the changes and correlation between the fermentation process and the quality of alcoholic and non-alcoholic beer product, especially the formation of diacetyl. On the other hand, spectrophotometric methods were applied to the determination of polyphenols content and the potential antioxidant activity of beer during different fermentation processes. with this aim, three modes of barley fermentation were used, specifically classical fermentation, stopped fermentation and thermal process. The results showed that the different fermentation modes had a major impact on diacetyl production. The highest concentration was obtained using stopped fermentation 0.36 mg/L, the lowest concentration value 0.07 mg/L was detected using the thermal process. Monitoring the increase of oxygen concentration between fermentation, filtration, and filling of the final product (32, 107, 130 ppm, respectively) has a significant impact on the concentration of diacetyl. The obtained results of spectrophotometric analysis showed that the total antioxidant activity changed during beer fermentation process and demonstrate that the extend of the antioxidant activity was very much dependent on the total polyphenolic content with a higher value in Hopped wort (13.41%, 65 mg GAE 100 mL−1, 28 mg CE 100 mL−1) for antioxidant potential, total phenolic content, and total flavonoids content, respectively, whereas the lowest values was detected in Non-alcoholic beer using thermal process (7.24%, 35 mg GAE 100 mL−1, 10 mg CE 100 mL−1) for antioxidant potential, total phenolic contents, and total flavonoids contents, respectively. Based on the results achieved, we reveal the impact of the fermentation process on the nutritional value of the final product.

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Changes in bitterness, antioxidant activity and total phenolic content of grapefruit juice fermented by Lactobacillus and Bifidobacterium strains

Acta Alimentaria ◽

10.1556/066.2020.49.1.13 ◽

2020 ◽

Vol 49 (1) ◽

pp. 103-110

Author(s):

A.M. Tran ◽

T.B. Nguyen ◽

V.D. Nguyen ◽

E. Bujna ◽

M.S. Dam ◽

...

Keyword(s):

Antioxidant Activity ◽

Acetic Acid ◽

Fermentation Process ◽

Grapefruit Juice ◽

Phenolic Content ◽

Total Phenolic ◽

Polyphenol Content ◽

Total Polyphenol ◽

Cell Counts ◽

Nutrition Supplementation

Four strains of Lactobacillus and Bifidobacterium including L. plantarum 01, L. fermentum D13, L. rhamnosus B01725, and B. bifidum B7.5 exhibiting naringinase production were applied in grapefruit juice fermentation. All investigated strains grew well in grapefruit juice without nutrition supplementation. In all cases, cell counts were 108–109 CFU ml−1 after 24 hours of fermentation. The highest lactic acid and acetic acid productions were observed in the case of strain L. plantarum 01. The L. plantarum 01 and L. fermentum D13 strains prefer glucose over fructose and sucrose, whereas fructose was the most favoured sugar for L. rhamnosus B01725 and B. bifidum B7.5. At the end of the fermentation process, antioxidant activity and total polyphenol content of grapefruit juice decreased in all cases, but the changes were not significant. Significant decrease of naringin was observed in the case of L. plantarum 01, 28% naringin in grapefruit juice was removed after fermentation. This result is promising for development of technology for production of probiotic grapefruit juice.

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Antioxidant Activity in Rheum emodi Wall (Himalayan Rhubarb)

Molecules ◽

10.3390/molecules26092555 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2555

Author(s):

Sang Koo Park ◽

Yoon Kyung Lee

Keyword(s):

Antioxidant Activity ◽

Ethyl Acetate ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Ethyl Acetate Fraction ◽

Total Phenolic ◽

Scavenging Activity ◽

Polyphenol Content ◽

Abts Assay ◽

Ic50 Values

Using natural products as antioxidant agents has been beneficial to replace synthetic products. Efforts have been made to profile the antioxidant capacities of natural resources, such as medicinal plants. The polyphenol content of Himalayan rhubarb, Rheum emodi wall, was measured and the antioxidant activity was determined using DPPH and ABTS+ assay, and the oxidative stress was assessed using SOD enzymatic assay. Five different solvent fractions, n-hexane, n-butanol, ethyl acetate, dichloromethane, and water, were used for screening the antioxidant capacity in effort to determine the optimum extraction solvent. The total phenolic contents for R. emodi fractions ranged from 27.76 to 209.21 mg of gallic acid equivalents (GAE)/g of dry weight. DPPH and ABTS+ assay results are presented into IC50 values, ranged from 21.52 to 2448.79 μg/mL and 90.25 to 1718.05 μg/mL, respectively. The ethyl acetate fraction had the highest antioxidant activity among other fractions. Also, n-butanol and water fractions showed significantly lower IC50 values than the positive control in DPPH radical scavenging activity. The IC50 values of SOD assay of fractions ranged from 2.31 to 64.78 μg/mL. A similar result was observed with ethyl acetate fraction showing the highest SOD radical scavenging activity. The study suggests that the ethyl acetate fraction of R. emodi possess the strongest antioxidant activity, thus the most efficient in extracting antioxidant contents. Moreover, a highly significant correlation was shown between total polyphenol content and antioxidant activity screening assays. The compounds related to the antioxidant activity of R. emodi were identified to myricitrin, myricetin 3-galloyl rhamnoside, and myricetin, which have not been reported in studies about R. emodi before.

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Evaluation of phenolic compounds and antioxidant activity in some edible flowers

Open Agriculture ◽

10.1515/opag-2020-0087 ◽

2020 ◽

Vol 5 (1) ◽

pp. 857-870

Author(s):

Fernando Gonçalves ◽

João Carlos Gonçalves ◽

Ana Cristina Ferrão ◽

Paula Correia ◽

Raquel P. F. Guiné

Keyword(s):

Antioxidant Activity ◽

Total Phenolics ◽

Total Phenolic ◽

Potential Health ◽

Phenolic Contents ◽

Spectrophotometric Methods ◽

Potential Source ◽

Successive Extraction ◽

Dpph Method ◽

Total Anthocyanins

AbstractRecently, edible flowers (EF) have aroused increased interest because of their aesthetic properties as well as potential health benefits related to the occurrence of some bioactive compounds. Therefore, the aim of this work was to evaluate the total phenolics, anthocyanins, flavonoids, and antioxidant activity (AOA) (following DPPH and ABTS methods) in eleven EF. The samples were subjected to three successive extraction steps using methanol, and these extracts were then analysed for the aforementioned properties using spectrophotometric methods. The obtained extracts were used for the quantification of phenolic composition and AOA. The results indicated that, among the flowers analysed in this study, red rose, pink rose, and red carnation possessed the highest total phenolic contents (27.53, 23.30, and 18.17 mg g−1 gallic acid equivalents, respectively), total anthocyanins (3.07, 1.97, and 4.47 mg g−1 catechin equivalents [CE], respectively), and AOA (12.07, 15.77, and 12.93 mg g−1 TE, respectively, as given by the DPPH method or 8.23, 9.27 and 8.00 mg g−1 TE, respectively, as given by the ABTS method). The flowers with highest flavonoids contents were red carnation, Mexican marigold, and pink rose (17.50, 16.90, and 16.57 mg g−1 CE, respectively). Cluster analysis grouped the analysed flowers into two groups, those richest in phenolics with AOA and those not so rich. Finally, some important correlations were observed between the total phenolics and the AOA. In conclusion, these flowers could represent a potential source of natural compounds with antioxidant capacity.

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Physicochemical Characterization and Functional Potential of Phaseolus vulgaris L. and Phaseolus coccineus L. Landrace Green Beans

Agronomy ◽

10.3390/agronomy11040803 ◽

2021 ◽

Vol 11 (4) ◽

pp. 803

Author(s):

Elia Nora Aquino-Bolaños ◽

Alma Karina Garzón-García ◽

Jimena Esther Alba-Jiménez ◽

José Luis Chávez-Servia ◽

Araceli Minerva Vera-Guzmán ◽

...

Keyword(s):

Antioxidant Activity ◽

Physicochemical Characterization ◽

Titratable Acidity ◽

Soluble Solids ◽

Total Phenolic ◽

Green Beans ◽

Total Sugars ◽

Total Soluble Solids ◽

Color Parameters

The green bean is an important crop worldwide, because it is rich in protein, dietary fiber, vitamins, and minerals, as well as bioactive compounds that provide it with important functional properties; however, the composition of many landraces is still unknown. The purpose of this project was to characterize Phaselus vulgaris and coccineus L. landrace green beans on pH, titratable acidity, total soluble solids, total sugars, color parameters, total phenols, monomeric anthocyanins, and in vitro antioxidant activity (DPPH and FRAP). Regarding the content of total sugars, differences were registered between both species, as opposed to results observed in total soluble solids. Color parameters showed higher reddish tones for P. vulgaris landraces, though P. coccineus had a higher total phenolic content, especially the reddish landraces, which correlated directly to a higher antioxidant activity by DPPH and FRAP. In the protein content, the species P. vulgaris registered the highest content. These results could contribute to a greater use and even promote the genetic improvement of the outstanding pods that serve as one of the main food products in rural regions for higher benefits.

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Antioxidant capacity and evaluation of total phenolic content of optimized blueberry (Vaccinium corymbosum) wine

Acta Scientiarum Technology ◽

10.4025/actascitechnol.v43i1.55134 ◽

2021 ◽

Vol 43 ◽

pp. e55134

Author(s):

Luis Angel Cabanillas-Bojorquez ◽

Octavio Valdez-Baro ◽

Erick Paul Gutierrez-Grijalva ◽

Jose Benigno Valdez-Torres ◽

Ramón Ignacio Castillo-López ◽

...

Keyword(s):

Antioxidant Capacity ◽

Total Phenolic Content ◽

Phenolic Content ◽

Vaccinium Corymbosum ◽

Soluble Solids ◽

Total Phenolic ◽

Potential Health ◽

Total Anthocyanin ◽

Fermentation Time ◽

Total Soluble Solids

Blueberry is a fruit consumed fresh and as an ingredient in formulations such as jam, juice, and wine. Wine is a widely consumed beverage and produced from different berries and fruits. Blueberry wine contains bio-compounds that could have a beneficial effect on health. Therefore, this study aimed to optimize blueberry wine by two response variables (total soluble solids and fermentation time) to obtain the highest alcohol percentage, pH, and lightness. In order to optimize the fermentation process, a central composite design was used. The optimized blueberry wine was obtained at total soluble solids of 25°Brix and fermentation time of 16 d. The optimized blueberry characteristics estimated were: alcohol percentage of 11.91%, pH of 2.98, and lightness (L*) of 26.22, and the optimized blueberry characteristics experimental were: alcohol percentage of 11.93±0.02%, pH of 2.97±0.01, and L* of 25.42±1.80. The optimized blueberry wine had a total phenolic content of 360.27±18.09 mg of gallic acid equivalents L-1, total anthocyanin content of 46.27±3.66 mg cyanidin-3 glucoside L-1, antioxidant capacity by ABTS and DDPH assays of 1,539.8±92.18 and 1,688.07±57.57 mM Trolox equivalent L-1, respectively. The results suggest that optimized blueberry wine can be considered a drink with potential health applications.

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Evaluation of fermented tea (kombucha) quality

Žemės ūkio mokslai ◽

10.6001/zemesukiomokslai.v26i4.4200 ◽

2020 ◽

Vol 26 (4) ◽

Author(s):

Vanesa Šliažaitė ◽

Aurelija Paulauskienė ◽

Aurimas Krasauskas

Keyword(s):

Antioxidant Activity ◽

Acetic Acid ◽

Sensory Evaluation ◽

Total Content ◽

Titratable Acidity ◽

Soluble Solids ◽

Total Phenolic ◽

Soluble Solids Content ◽

Fermentation Conditions ◽

Solids Content

The research was done at Aleksandras Stulginskis University (Vytautas Magnus University Agriculture Academy since 2019) in 2017–2018. The research object was kombucha beverage brewed from Camellia sinensis L. black, green, oolong, pu-erh tea and fermented for 9 and 22 days by microorganisms at different room lighting conditions. The soluble solids content, active acidity and titratable acidity were determined in teas fermented for 22 days. The total amount of phenolics compounds, antioxidant activity, yeast colonies and sensory evaluation of tea were determined in teas fermented for 9 days. The research results showed that the quality of fermented tea was dependent on the tea species, but fermentation conditions were not essential. During the fermentation the soluble solids content of tea decreased by an average of 0.60% and the content of acetic acid increased by 0.34%. The highest content of acetic acid was found on the 22nd day of fermentation in all species of teas. The active acidity (pH) of all investigated species of teas decreased significantly during the fermentation process. The total content of phenolic compunds in all species of teas during the fermentation increased from 20 to 57% regardless of fermentation conditions. The highest content of total phenolic compounds was established in teas fermented for 9 days. The antioxidant activity of teas fermented for 9 days varied depending on the fermentation conditions. For black and green teas fermented in the light the antioxidant activity decreased, for oolong and pu-erh teas fermented in the dark the antioxidant activity increased. The number of yeast colonies increased in all tea samples during the fermentation. The best taste was fixed for pu-erh tea, which scored the highest (11.4) in sensory evaluation.

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POLYPHENOL CONTENT AND ANTIOXIDANT POTENTIAL OF Allophylus edulis (A. St.-Hil. et al.) Hieron. ex Niederl. AND Cupania vernalis Cambess. (SAPINDACEAE)

Revista Árvore ◽

10.1590/1806-908820210000007 ◽

2021 ◽

Vol 45 ◽

Author(s):

Andréa Michel Sobottka ◽

Elisandra Tessaro ◽

Suelen Maier da Silva ◽

Marina Pedron ◽

Lara Tortini Seffrin

Keyword(s):

Antioxidant Activity ◽

Ethyl Acetate ◽

Skin Diseases ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Ethyl Acetate Fraction ◽

Antioxidant Potential ◽

Total Phenolic ◽

Butanol Fraction ◽

Degraded Ecosystems

ABSTRACT Allophylus edulis and Cupania vernalis (Sapindaceae) are Brazilian native trees used as medicinal plants for the treatment of respiratory, digestive, circulatory, and skin diseases. Ubiquitously distributed in the Brazilian territory, these species are indicated for mixed plantations aimed at the recovery of degraded ecosystems. In this study, the total phenolic content (TPC) and total flavonoid content (TFC), and the antioxidant activity of extracts and fractions obtained from A. edulis and C. vernalis leaves were assessed. The TPC and TFC was determined spectrophotometrically. Antioxidant activity was evaluated through radical scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). The extracts were obtained by two methods: maceration (method 1) and Soxhlet (method 2). Solvents of increasing polarity (hexane, dichloromethane, ethyl acetate, and n-butanol) were used to obtained the fractions. The results showed that the ethyl acetate fraction from A. edulis, obtained from the maceration method, had the highest TPC (442.0 ± 18.2 mg GAE g-1) and TFC (58.1 ± 0.4 mg RUE g-1), and antioxidant activity (EC50 = 43.6 ± 2.6 µg mL-1). By C. vernalis, superior results were obtained with the n-butanol fraction (TPC = 126.1 ± 5.8 mg GAE g-1, TFC = 37.7 ± 0.6 mg RUE g-1). The highest antioxidant potential was found in the crude hydroalcoholic extract (EC50 = 816.1 ± 50.9 µg mL-1) and butanol fraction (1,156.4 ± 3.8 µg mL-1). The results of this study show that the fractions obtained by maceration and liquid-liquid partition with more polar solvents (ethyl acetate and n-butanol) are the richest in TPC and TFC, and presented the greater antioxidant activity. Comparing the two plants, A. edulis showed the best results, with a high content of TPC, TFC, and antioxidant potential, and therefore may be used to treat diseases related to oxidative stress.

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Loranthus pulverulentus: A Potent Source of Natural Antioxidants and Alternative Medicine

Journal of Chemistry ◽

10.1155/2013/250739 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Muhammad Asam Raza ◽

Rukhsana Kausar ◽

Faraz Ali Rana ◽

Muhammad Danish ◽

Durre Shahwar ◽

...

Keyword(s):

Antioxidant Activity ◽

Ethyl Acetate ◽

Natural Antioxidants ◽

Stem Bark ◽

Antioxidant Potential ◽

Total Phenolic ◽

Strong Correlations ◽

Phenolic Contents ◽

Total Phenolic Contents ◽

Total Antioxidant

This study was designed to evaluate the antioxidant potential ofLoranthus pulverulentus. Stem bark, leaves, and seeds ofLoranthus pulverulentuswere extracted in methanol:water (90 : 10) and partitioned with n-hexane, chloroform, ethyl acetate, and n-butanol successively using partition chromatography. Total phenolic contents and antioxidant potential were checked using standard protocols. Total phenolic contents of all extracts were determined, using Folin–Ciocalteu reagent, and ranged between 151 ± 2.1 and 396 ± 1.6 for stem bark, 137 ± 0.9 and 430 ± 2.2 for, and 39 ± 0.6 and 231 ± 1.7 for seeds. The antioxidant potential of extracts was evaluated; namely, DPPH, FRAP, and total antioxidant models. The ethyl acetate extract of stem-bark, leaves, and seeds showed the highest activity in DPPH (94.5 ± 2.1%, 96.30 ± 0.9%, and 92.30 ± 1.1%, IC5015.9 ± 0.5 μg, 14.5 ± 0.8, and 102.7 ± 1.3, resp.), FRAP (7.7 ± 0.6, 7.5 ± 0.7 and 6.6 ± 0.7, resp.), and total antioxidant (0.95 ± 0.09, 1.19 ± 0.09, and 0.686 ± 0.08, resp.). Strong correlations were observed between total phenols versus total antioxidant activity, DPPH, and FRAP withR2values ranging from 0.8185 to 0.9951 (stem-bark), 0.6728 to 0.8648 (leaves), and 0.8658 to 0.9910 (seed) which indicated that phenolic contents are the major constituents responsible for antioxidant activity.

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Biopreservation of Fresh Strawberries by Carboxymethyl Cellulose Edible Coatings Enriched with a Bacteriocin from Bacillus methylotrophicus BM47

Food Technology and Biotechnology ◽

10.17113/ftb.57.02.19.6128 ◽

2019 ◽

Vol 57 (2) ◽

pp. 230-237 ◽

Cited By ~ 4

Author(s):

Yulian Tumbarski ◽

Radosveta Nikolova ◽

Nadezhda Petkova ◽

Ivan Ivanov ◽

Anna Lante

Keyword(s):

Antioxidant Activity ◽

Mass Loss ◽

Shelf Life ◽

Carboxymethyl Cellulose ◽

Storage Period ◽

Soluble Solids ◽

Life Extension ◽

Total Phenolic ◽

Edible Coatings ◽

Bacillus Methylotrophicus

Bacteriocins are a large group of antimicrobial compounds that are synthesized by representatives of the genus Bacillus and lactic acid bacteria. They are used extensively in the food industry as biopreservatives. Incorporated in the composition of edible coatings, bacteriocins can reduce microbial growth and decay incidence in perishable fruits, thus improving product shelf-life and commercial appearance. The present study aims to investigate the effect of edible coatings of 0.5 % carboxymethyl cellulose (CMC) enriched with a purified bacteriocin from Bacillus methylotrophicus BM47 on the shelf-life extension of fresh strawberries. During storage at 4 °C and 75 % relative humidity for 16 days, the measurements of mass loss, decay percentage, total soluble solids (TSS), titratable acidity (TA), pH, organic acids, total phenolic and anthocyanin contents and antioxidant activity were made. The results demonstrate that the application of edible coatings with 0.5 % CMC and 0.5 % CMC with bacteriocin (CMC+B) led to a significant decrease of mass loss in the treated strawberries compared to the uncoated fruit. After the 8th day of storage, significant reductions in decay percentage along with the absence of fungal growth in CMC+B-coated fruit were observed in comparison with the CMC-coated and control strawberries. During the second half of the storage period, CMC and CMC+B treatments reduced TSS amount in the coated fruit compared to the control, but did not affect the increase of TA and decrease of pH values that are normally associated with postharvest changes. The CMC and CMC+B coatings did not prevent the decrease of ascorbic acid, and total phenolic and anthocyanin contents during cold storage. The application of CMC and CMC+B coatings had a significant inhibitory effect on decreasing the antioxidant activity throughout the storage period and maintained the antioxidant levels in both treatments close to the initial value of 76.8 mmol Trolox equivalents per 100 g of fresh mass.

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