High-Throughput Screening and Characterization of Phenolic Compounds in Stone Fruits Waste by LC-ESI-QTOF-MS/MS and Their Potential Antioxidant Activities

Stone fruits, including peach (Prunus persica L.), nectarine (Prunus nucipersica L.), plum (Prunus domestica L.) and apricot (Prunus armeniaca L.) are common commercial fruits in the market. However, a huge amount of stone fruits waste is produced throughout the food supply chain during picking, handling, processing, packaging, storage, transportation, retailing and final consumption. These stone fruits waste contain high phenolic content which are the main contributors to the antioxidant potential and associated health benefits. The antioxidant results showed that plum waste contained higher concentrations of total phenolic content (TPC) (0.94 ± 0.07 mg gallic acid equivalents (GAE)/g) and total flavonoid content (TFC) (0.34 ± 0.01 mg quercetin equivalents (QE)/g), while apricot waste contained a higher concentration of total tannin content (TTC) (0.19 ± 0.03 mg catechin equivalents (CE)/g) and DPPH activity (1.47 ± 0.12 mg ascorbic acid equivalents (AAE)/g). However, nectarine waste had higher antioxidant capacity in ferric reducing-antioxidant power (FRAP) (0.98 ± 0.02 mg AAE/g) and total antioxidant capacity (TAC) (0.91 ± 0.09 mg AAE/g) assays, while peach waste showed higher antioxidant capacity in 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay (0.43 ± 0.09 mg AAE/g) as compared to other stone fruits waste. Qualitative and quantitative phenolic analysis of Australian grown stone fruits waste were conducted by liquid chromatography coupled with electrospray-ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS) and HPLC-photodiode array detection (PDA). The LC-ESI-QTOF-MS/MS result indicates that 59 phenolic compounds were tentatively characterized in peach (33 compounds), nectarine (28), plum (38) and apricot (23). The HPLC-PDA indicated that p-hydroxybenzoic acid (18.64 ± 1.30 mg/g) was detected to be the most dominant phenolic acid and quercetin (19.68 ± 1.38 mg/g) was the most significant flavonoid in stone fruits waste. Hence, it could be concluded that stone fruit waste contains various phenolic compounds and have antioxidant potential. The results could support the applications of these stone fruit wastes in other food, feed, nutraceutical and pharmaceutical industries.

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LC-ESI-QTOF/MS Characterization of Phenolic Compounds from Medicinal Plants (Hops and Juniper Berries) and Their Antioxidant Activity

Foods ◽

10.3390/foods9010007 ◽

2019 ◽

Vol 9 (1) ◽

pp. 7 ◽

Cited By ~ 9

Author(s):

Jiafei Tang ◽

Frank R. Dunshea ◽

Hafiz A. R. Suleria

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

Medicinal Plants ◽

Antioxidant Capacity ◽

Phenolic Acids ◽

Phenolic Content ◽

Total Phenolic ◽

High Concentration ◽

Antioxidant Power ◽

Pharmaceutical Industries

Hops (Humulus lupulus L.) and juniper berries (Juniperus communis L.) are two important medicinal plants widely used in the food, beverage, and pharmaceutical industries due to their strong antioxidant capacity, which is attributed to the presence of polyphenols. The present study is conducted to comprehensively characterize polyphenols from hops and juniper berries using liquid chromatography coupled with electrospray-ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS) to assess their antioxidant capacity. For polyphenol estimation, total phenolic content, flavonoids and tannins were measured, while for antioxidant capacity, three different antioxidant assays including the 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant assay, the 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cation decolorization assay and the ferric reducing-antioxidant power (FRAP) assay were used. Hops presented the higher phenolic content (23.11 ± 0.03 mg/g dw) which corresponded to its strong antioxidant activity as compared to the juniper berries. Using LC-ESI-QTOF/MS, a total of 148 phenolic compounds were tentatively identified in juniper and hops, among which phenolic acids (including hydroxybenzoic acids, hydroxycinnamic acids and hydroxyphenylpropanoic acids) and flavonoids (mainly anthocyanins, flavones, flavonols, and isoflavonoids) were the main polyphenols, which may contribute to their antioxidant capacity. Furthermore, the HPLC quantitative analysis showed that both samples had a high concentration of phenolic acids and flavonoids. In the HPLC quantification, the predominant phenolic acids in hops and juniper berries were chlorogenic acid (16.48 ± 0.03 mg/g dw) and protocatechuic acid (11.46 ± 0.03 mg/g dw), respectively. The obtained results highlight the importance of hops and juniper berries as a rich source of functional ingredients in different food, beverage, and pharmaceutical industries.

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Variety and Year Impact on Phenolic Content of Arkansas-Grown Sweetpotato Leaves

Current Developments in Nutrition ◽

10.1093/cdn/nzaa045_004 ◽

2020 ◽

Vol 4 (Supplement_2) ◽

pp. 371-371

Author(s):

Josue Bolanos ◽

Sun-Ok Lee ◽

Luke Howard ◽

Cindi Brownmiller ◽

Shahidul Islam ◽

...

Keyword(s):

Phenolic Compounds ◽

Antioxidant Capacity ◽

Chlorogenic Acid ◽

Total Phenolic Content ◽

Phenolic Content ◽

Statistical Significance ◽

Radical Scavenging ◽

Dry Weight ◽

Antioxidant Potential ◽

Total Phenolic

Abstract Objectives Sweetpotato leaf (SPL) is a natural source of phenolic compounds with potential utility as an antioxidant. The study aimed to measure the impacts of the years on SPL total phenolic content and antioxidant capacity and to identify and quantify the individual phenolic compounds. Methods Sweetpotato leaves in 2018 (27 varieties) and 2019 (24 varieties) were grinded and lyophilized. Phenolic compounds were extracted with 70% ethanol from SPLs. Total phenolic content was determined by Folin-Ciocalteu method and antioxidant potential was determined by DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay. Five SPL samples with statistically highest antioxidant capacity were identified and quantified by HPLC. All statistical analyses were carried out by SAS software using ANOVA. Statistical significance was accepted at P < 0.05. Results The average of total phenolic contents in 2018 SPL samples was 43 ± 13 mg gallic acid equivalent (GAE)/g dry weight (DW) SPL whereas in 2019, it was 53 ± 9 mg GAE/g dry weight SPL. Antioxidant capacity in 2018 was 110 ± 75 µmol Trolox equivalent (TE)/g dry weight SPL whereas in 2019, it was 132 ± 32 µmol TE/g dry weight SPL. SPL1 had the highest antioxidant potential, followed by SPL9, SPL3, SPL28, and SPL11 (P < 0.05). The concentrations of major identified phenolics from the five SPL samples (#1, 9, 3, 28, and 11) in dry weight of SPL were: chlorogenic acid at 3.05 ± 0.35 mg/g, 5-monocaffeoylquinic acid (CQA) at 0.71 ± 0.06 mg chlorogenic acid equivalent (ChAE)/g, 4-CQA at 0.99 ± 0.07 mg ChAE/g, 3,4-diCQA at 1.22 ± 0.18 mg ChAE/g, 3,4,5-triCQA at 1.2 ± 0.18 mg ChAE/g, and 3,5-diCQA at 15.5 ± 4.05 mg ChAE/g. 3,5-diCQA, the predominant phenolic, was present in the highest amounts in SPL1. Conclusions The results showed that sweetpotato leaves collected in 2019 contained higher total phenolics and antioxidant capacity than the ones collected in 2018. Phenolic compounds have strong antioxidant activity in Arkansas-grown sweetpotato leaves. This study warrants further investigation of sweetpotato leaves to be utilized as an antioxidant. Funding Sources The work was supported by USDA-NIFA.

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Ultrasound-Assisted Extraction of Antioxidants from Baccharis dracunculifolia and Green Propolis

Processes ◽

10.3390/pr8121530 ◽

2020 ◽

Vol 8 (12) ◽

pp. 1530

Author(s):

Renata Iara Cavalaro ◽

Luis Felipe de Freitas Fabricio ◽

Thais Maria Ferreira de Souza Vieira

Keyword(s):

Phenolic Compounds ◽

Antioxidant Capacity ◽

Total Phenolic Content ◽

Phenolic Content ◽

Southeastern Brazil ◽

Total Phenolic ◽

Ultrasound Assisted Extraction ◽

Antioxidant Power ◽

Assisted Extraction ◽

Ultrasound Assisted

Baccharis dracunculifolia or rosemary-of-field is the principal botanical source used by Africanized bees Apis mellifera L. to produce green propolis in Southeastern Brazil. The phenolic compounds present in the plant and green propolis have been reported to be responsible for biological activities such as antioxidant capacity. This study aimed to optimize the ultrasound-assisted extraction of antioxidants compounds from rosemary-of-field using a central composite rotatable design (CCRD), and compare results to green propolis extract. An experimental design was performed to obtain responses of total phenolic content and antioxidant capacity. The results allowed observing that the optimum condition for both Baccharis dracunculifolia floral bud and raw green propolis antioxidant extraction was obtained with 99% ethanol solution. In this condition, Total Phenolic Content (TPC), Ferric Reducing Antioxidant Power (FRAP), and 2,2-diphenyl-1-picryl-hydrazyl (DPPH) values were 612.14 mg GAE. g−1 sample, 534.39 µM ferrous sulfate g−1 sample, and 72.37 µmol TEAC. g−1 sample, respectively, for floral buds. These results have confirmed that optimization is a key step for effective and sustainable extraction processes to be feasible on an industrial scale. The proposed process can be easily adopted on a larger scale, as it uses very few inputs and presents straightforward steps, with the advantage of high efficiency in the extraction of phenolic compounds from the studied matrices compared to the results from the literature. The high concentration of antioxidants indicates that the products obtained can be considered as a sustainable bioactive source for food and cosmetic purposes.

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Evaluation of Extracts Obtained from FruitWastes Using Different Methods

Ingeniería ◽

10.14483/23448393.16525 ◽

2020 ◽

Vol 26 (1) ◽

pp. 77-92

Author(s):

Ciliana Florez Montes ◽

Andrés Felipe Rojas González ◽

Sneyder Rodríguez Barona

Keyword(s):

Phenolic Compounds ◽

Antioxidant Capacity ◽

Total Phenolic ◽

Microwave Assisted Extraction ◽

Total Phenolic Compounds ◽

Grape Seeds ◽

Microwave Assisted ◽

Assisted Extraction ◽

Pharmaceutical Industries

Context: Currently, the increase in agroindustrial waste generation has encouraged the search for viable use alternatives. In this paper, four methods to obtain extracts from mango, soursop, and grape peels, as well as and grape seeds, are studied. Their efficiency is analyzed through extraction yields and antioxidant capacity characterization of the extracts. Method: The extraction was performed using solvent, Soxhlet, microwave-assisted, and ultrasound assisted extraction. The characterization of the extracts was made by total phenolic compounds and flavonoids quantification, as well as antioxidant capacity determination, using the DPPH, FRAP, and ORAC tests. Results: It was found that grape seed extracts obtained by different extraction methods, highlighting those obtained by microwave assisted extraction, present a high total content phenolic compounds (>321.381,41 ± 3.476,85 μg Gallic Acid/g) and flavonoids (>103.232,01 ± 4.638,19 μg Quercetin/g), in addition to high antioxidant activity, according to the results of the DPPH (<1,06 ± 0,01), FRAP (>152.280,08 ± 5.197,53 µg TROLOX/g), and ORAC (>124.566,81 ± 581,96 μg TROLOX/g) tests. Conclusions: The results presented in this study suggest that the extracts obtained from grape seeds, especially those obtained by means of microwave-assisted extraction, have a potential use in food and pharmaceutical industries, due to their high antioxidant capacity and their total phenolic compounds and flavonoids content.

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Phytochemical Evaluation and In-vitro Antioxidant Potential of whole plant of Caralluma adscendens

Research Journal of Pharmacy and Technology ◽

10.52711/0974-360x.2021.00489 ◽

2021 ◽

pp. 2774-2778

Author(s):

Divya Yada ◽

T. Sivakkumar ◽

M. Sudhakar

Keyword(s):

Nitric Oxide ◽

Total Phenolic Content ◽

Phenolic Content ◽

Ethanolic Extract ◽

Antioxidant Potential ◽

Total Phenolic ◽

Flavonoid Content ◽

Antioxidant Power ◽

Whole Plant

The current line of investigation was focused at perusing the presence of phytochemical constituents, investigation of total phenol and flavonoid content, the antioxidant potential of various extracts of Caralluma adscendens whole plant using various in-vitro assays. The dried plant powder was extracted with various solvents based on polarity (Pet ether, Chloroform, Ethyl acetate, Ethanol and Aqueous) by hot continuous extraction in Soxhlet's apparatus and Extracts were dried. Phytoconstituents present in each extract was examined by performing preliminary phytochemical screening. Total Phenolic Content (TPC), Total Flavonoid Content (TFC) and Antioxidant potential for crude extracts were studied by DPPH, nitric oxide scavenging and FRAP methods. The total phenolic content and flavonoid content of Ethanolic extract of plant was found to be 80.08±0.629mg and 70.88±1.170mg of GAE and Quercetin equivalents respectively. The Ethanolic extract exhibited potent antioxidant activity as determined by 2,2-diphenyl-1-picrylhydrazyl(DPPH), nitric oxide scavenging and ferric reducing antioxidant power assays(FRAP) than the other extracts. The IC50 values for the Ethanolic extract of Caralluma adscendens was found to be 214.765±0.224 µg/ml and 215.928±0.506µg/ml by DPPH and nitric oxide scavenging assays respectively.

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Screening and Characterization of Phenolic Compounds and Their Antioxidant Capacity in Different Fruit Peels

Foods ◽

10.3390/foods9091206 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1206 ◽

Cited By ~ 2

Author(s):

Hafiz A. R. Suleria ◽

Colin J. Barrow ◽

Frank R. Dunshea

Keyword(s):

Phenolic Compounds ◽

Antioxidant Capacity ◽

Phenolic Acids ◽

Phenolic Content ◽

Antioxidant Properties ◽

Antioxidant Potential ◽

Fruit Peel ◽

Diverse Range ◽

Mango Peel

Fruit peels have a diverse range of phytochemicals including carotenoids, vitamins, dietary fibres, and phenolic compounds, some with remarkable antioxidant properties. Nevertheless, the comprehensive screening and characterization of the complex array of phenolic compounds in different fruit peels is limited. This study aimed to determine the polyphenol content and their antioxidant potential in twenty different fruit peel samples in an ethanolic extraction, including their comprehensive characterization and quantification using the LC-MS/MS and HPLC. The obtained results showed that the mango peel exhibited the highest phenolic content for TPC (27.51 ± 0.63 mg GAE/g) and TFC (1.75 ± 0.08 mg QE/g), while the TTC (9.01 ± 0.20 mg CE/g) was slightly higher in the avocado peel than mango peel (8.99 ± 0.13 mg CE/g). In terms of antioxidant potential, the grapefruit peel had the highest radical scavenging capacities for the DPPH (9.17 ± 0.19 mg AAE/g), ABTS (10.79 ± 0.56 mg AAE/g), ferric reducing capacity in FRAP (9.22 ± 0.25 mg AA/g), and total antioxidant capacity, TAC (8.77 ± 0.34 mg AAE/g) compared to other fruit peel samples. The application of LC-ESI-QTOF-MS/MS tentatively identified and characterized a total of 176 phenolics, including phenolic acids (49), flavonoids (86), lignans (11), stilbene (5) and other polyphenols (25) in all twenty peel samples. From HPLC-PDA quantification, the mango peel sample showed significantly higher phenolic content, particularly for phenolic acids (gallic acid, 14.5 ± 0.4 mg/g) and flavonoids (quercetin, 11.9 ± 0.4 mg/g), as compared to other fruit peel samples. These results highlight the importance of fruit peels as a potential source of polyphenols. This study provides supportive information for the utilization of different phenolic rich fruit peels as ingredients in food, feed, and nutraceutical products.

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Seasonal variations in phenolic compounds and antioxidant capacity ofCornus stoloniferaplant material: Applications in agriculture

Canadian Journal of Plant Science ◽

10.4141/cjps2012-310 ◽

2013 ◽

Vol 93 (4) ◽

pp. 725-734 ◽

Cited By ~ 10

Author(s):

Cara K. Isaak ◽

Jay C. Petkau ◽

O Karmin ◽

Kim Ominski ◽

Juan Carlos Rodriguez-Lecompte ◽

...

Keyword(s):

Phenolic Compounds ◽

Antioxidant Capacity ◽

Seasonal Variations ◽

Plant Material ◽

Phenolic Content ◽

Ultra Performance Liquid Chromatography ◽

Total Phenolic ◽

Anthocyanin Content ◽

Cornus Stolonifera ◽

Total Anthocyanins

Isaak, C. K., Petkau, J. C., O, K., Ominski, K., Rodriguez-Lecompte, J. C, and Siow, Y. L. 2013. Seasonal variations in phenolic compounds and antioxidant capacity of Cornus stolonifera plant material: Applications in agriculture. Can. J. Plant Sci. 93: 725–734. The present study was carried out to establish the antioxidant capacity of plant material of Cornus stolonifera (syn. Cornus sericea, Red Osier Dogwood) grown in Manitoba, by measuring total phenolic content and oxygen radical absorbance capacity (ORAC) over a 3-yr period. The presence and concentrations of flavonoids that might account for antioxidant abilities were investigated using ultra-performance liquid chromatography and a total anthocyanins assay. Both ORAC levels and phenolic content increased during the spring, peaked during the summer months (1631.65±166.30 µmol trolox equivalents g−1DW in July 2011, 220.38±2.29 mg gallic acid equivalents g−1DW in August 2012), and then declined during the fall in all 3 yr. Analysis of individual flavonoids in 2010 samples revealed that high levels of rutin, a glycoside of quercetin, were present ranging from 7.46±0.09 (July 2010) to 18.77±0.23 mg g−1dried sample (October 2010). Anthocyanin content was high in the spring, very low in the summer months, and increased in the fall over all 3 yr. Although polyphenolic and antioxidant content in Cornus spp. plants have been largely attributed to their berries, results from this study demonstrate that other plant material may also be an abundant source of these compounds.

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Chitosan Upregulates the Genes of the ROS Pathway and Enhances the Antioxidant Potential of Grape (Vitis vinifera L. ‘Touriga Franca’ and ’Tinto Cão’) Tissues

Antioxidants ◽

10.3390/antiox8110525 ◽

2019 ◽

Vol 8 (11) ◽

pp. 525 ◽

Cited By ~ 8

Author(s):

Singh ◽

Soares ◽

Goufo ◽

Castro ◽

Cosme ◽

...

Keyword(s):

Superoxide Dismutase ◽

Phenolic Compounds ◽

Amine Oxidase ◽

Crop Protection ◽

Antioxidant Potential ◽

Total Phenolic ◽

Vitis Vinifera L ◽

Ros Scavenging ◽

Antioxidant Power ◽

Before And After

Chitosan is an environmentally-friendly active molecule that has been explored for numerous agricultural uses. Its use in crop protection is well-known, however, other properties, such as bioactivity, deserve attention. Moreover, the modes of actions of chitosan remain to be elucidated. The present study assessed the levels of total phenolic compounds, the antioxidant potential, and the expression of reactive oxygen species (ROS) scavenging genes in the berries (skins and seeds), leaves, cluster stems, and shoots upon chitosan application on two red grapevine varieties (Touriga Franca and Tinto Cão). The application of chitosan on the whole vine before and after veraison led to the increased levels of polyphenols, anthocyanins, and tannins in Tinto Cão berries, and polyphenols and tannins in Touriga Franca berries, respectively. CUPric Reducing Antioxidant Capacity (CUPRAC) and Ferric Reducing Antioxidant Power (FRAP) assays indicated an increase in the antioxidant potential of berries. With the exception of ascorbate peroxidase (APX), all the ROS pathway genes tested, i.e., iron-superoxide dismutase (Fe-SOD), copper-zinc-superoxide dismutase (Cu/Zn-SOD), catalase (CAT), glutathione reductase (GR), glutaredoxin (Grx), respiratory burst oxidase (Rboh), amine oxidase (AO), peroxidase (POD) and polyphenol oxidase (PPO), were found up-regulated in chitosan-treated berries. Results from the analyses of leaves, stems, and shoots revealed that chitosan not only induced the synthesis of phenolic compounds but also acted as a facilitator for the transfer of polyphenols from the leaves to the berries.

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Phenolic Fingerprinting, Antioxidant, and Deterrent Potentials of Persicaria maculosa Extracts

Molecules ◽

10.3390/molecules25133054 ◽

2020 ◽

Vol 25 (13) ◽

pp. 3054 ◽

Cited By ~ 1

Author(s):

Luisa Quesada-Romero ◽

Carlos Fernández-Galleguillos ◽

Jan Bergmann ◽

María-Eugenia Amorós ◽

Felipe Jiménez-Aspee ◽

...

Keyword(s):

Phenolic Compounds ◽

Antioxidant Capacity ◽

Macrosiphum Euphorbiae ◽

Total Phenolic ◽

Phenolic Profile ◽

Antioxidant Power ◽

Aerial Parts ◽

Ferric Reducing Antioxidant Power ◽

First Time ◽

Derivatives Of

Persicaria maculosa (Polygonaceae) (known as lady’s thumb) is an annual morphologically variable weed that is widely distributed in Chile. The purpose of this study was to investigate the antifeedant potential of methanolic (MeOH), ethanolic (EtOH), and dichloromethane (DCM) extracts from the aerial parts of this plant collected in the Valparaíso and Curicó provinces (Chile) and relate this activity to the antioxidant capacity and the presence of phenolic compounds in the extracts. A phenolic profile based on HPLC-ESI-MS/MS allowed the identification of 26 phenolic compounds, most of them glycosyl derivatives of isorhamnetin, quercetin, and kaempferol. In addition, the total phenolic content (TP), total flavonoids (TF), and antioxidant activity measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion scavenging (O2−), ferric-reducing antioxidant power (FRAP), and cupric-reducing antioxidant capacity (CUPRAC) of the extracts are reported. The antifeedant potentials of the plant extracts were tested against Epilachna paenulata, Pseudaletia adultera, Macrosiphum euphorbiae, and Diaphorina citri insects for the first time. The activity against the aphid M. euphorbiae was significant for the DCM extracts of plants from Valparaíso and Curicó (settling % = 23% ± 4% and 23% ± 5%, respectively). The antifeedant activities against the beetle E. paenulata and the lepidoptera P. adultera were significant for Valparaíso extracts, especially when tested against E. Paenulata (IFP = 1.0 ± 0.0). Finally, the MeOH and EtOH extracts from Valparaíso plants reduced the diet consumption of the psilid D. citri (p < 0.05). The results showed that P. maculosa is a good source of flavonoids with some antioxidant capacities and has potential interest as botanical eco-friendly alternative with deterrent activity.

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Evaluation of the Behavior of Phenolic Compounds and Steviol Glycosides of Sonicated Strawberry Juice Sweetened with Stevia (Stevia rebaudiana Bertoni)

Molecules ◽

10.3390/molecules24071202 ◽

2019 ◽

Vol 24 (7) ◽

pp. 1202 ◽

Cited By ~ 1

Author(s):

Jana Šic Žlabur ◽

Nadica Dobričević ◽

Mladen Brnčić ◽

Francisco J. Barba ◽

Jose M. Lorenzo ◽

...

Keyword(s):

Phenolic Compounds ◽

Antioxidant Capacity ◽

Phenolic Content ◽

Stevia Rebaudiana ◽

Processing Parameters ◽

Total Phenolic ◽

Steviol Glycosides ◽

Total Flavonoids ◽

Probe Diameter ◽

Strawberry Juice

In this study, the influence of stevia addition and sonication processing parameters on the phenolic content and profile as well as the steviol glycosides of strawberry juice-based samples was investigated. For this purpose, three matrices—control samples of strawberry juices without green stevia powder (CS), strawberry juices with green stevia powder (JGSP), and sonicated juices with green stevia powder (SJGSP)—were prepared. For sonication purposes, different conditions regarding probe diameters (7 mm and 22 mm), amplitudes (50%, 75%, and 100%), and time (15 min, 20 min, and 25 min) were tested. The results that were obtained upon the measurement of the total phenolic content, total flavonoids, steviol glycosides, and antioxidant capacity showed significant differences according to the matrices evaluated, obtaining overall higher values in the samples with stevia added. Moreover, when sonication was evaluated, it was found that a higher amplitude (100%), a larger probe diameter (22 mm), and a longer sonication period (25 min) led to higher values. Flavones such as luteolin and apigenin were identified and quantified in JGSP and SJGSP, while they were not found in CS. Besides these phenolic compounds, kaempferol, quercetin, pyrogallic acid, 4-methylcatechol, and 4-methoxybenzoic acid were also identified and quantified. Similarly to the total phenolic compounds, total flavonoids, and total antioxidant capacity, an increased amount of these compounds was found in SJGSP, especially after using the most intense sonication conditions. Therefore, the use of sonication together with stevia added could be a useful tool to preserve strawberry juices, increasing at the same time the sweetness and the antioxidant value of the beverages.

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