Analyses of Metals Impact on Humulus lupulus Strobili Antioxidant Capacity

This paper presents results of analyses of metal ions effects on hop strobili antioxidant characteristics. Determination of total phenols (TP), total flavonoids (TF) and fifteen phenolic compounds, as well as the antioxidant activity (DPPH, ABTS and FRAP) of hop extracts from eight samples was conducted using UV/Vis spectrophotometry and HPLC method. Contents of 24 elements in mineralized hop samples were determined by ICP-OES. Very strong negative relationship between TP, TF, antioxidant capacity results and Pb, Co, Cr, Sb and Na was determined applying principal component and cluster analyses. Namely, the higher concentrations of these metals were associated with lower contents of TP and TF and lower values of antioxidant tests. Impact of metal ions on phenolic and flavonoids content and antioxidant activity of hop strobili has not been previously published.

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Color and Antioxidant Capacity Preservation of Opuntia spp. Juices by Spray-drying Microencapsulation.

Journal of Food Research ◽

10.5539/jfr.v7n3p16 ◽

2018 ◽

Vol 7 (3) ◽

pp. 16 ◽

Cited By ~ 1

Author(s):

Alberto Castañeda-Yañez ◽

Sandra T. Martín-del-Campo ◽

Alejandra San-Martin ◽

Anaberta Cardador-Martínez

Keyword(s):

Principal Component Analysis ◽

Protective Effect ◽

Antioxidant Capacity ◽

Spray Drying ◽

Principal Component ◽

Natural Colorants ◽

The Matrix ◽

Pear Juice ◽

Antioxidant Characteristics ◽

Opuntia Spp

In this work, it was evaluated the effect of microencapsulation using spray drying over natural colorants present in two varieties (red and purple) of prickly pear juice (Opuntia spp.), using three kinds of carrier agents (matrixes). The dried samples after microencapsulation retained a high total amount of the betalains and their antioxidant characteristics. However, some individual betalains were lost after microencapsulation. According to ANOVA results, matrix 3204 showed a more protective effect than matrix 4801 in both microencapsulated juices over color, individual betalains, and antioxidant capacity. Globally, the protective effect was better for purple juices than red juices no matter the matrix used. Principal Component Analysis (PCA) confirmed these results. Matrix 3204 resulted in the best carrier agent since it gave a less disperse PCA group for both color juices. The parameters that separated both PCA matrixes groups were L*, a*, b* and DPPH.

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ICP-OES determination of trace metal ions after preconcentration by 4-(8-hydroxy-5-quinolylazo)naphthalenesulfonic acid modified silica gel

Journal of Molecular Structure ◽

10.1016/j.molstruc.2008.02.037 ◽

2008 ◽

Vol 891 (1-3) ◽

pp. 45-49 ◽

Cited By ~ 20

Author(s):

Xijun Chang ◽

Haixia Luo ◽

Yuemei Cui ◽

Xiangbing Zhu ◽

Yunhui Zhai ◽

...

Keyword(s):

Trace Metal ◽

Metal Ions ◽

Silica Gel ◽

Icp Oes ◽

Modified Silica ◽

Modified Silica Gel ◽

Trace Metal Ions

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Determination of Titanium Content as Principal Components in Pyrotechnic Compositions Used for Fireworks and Firecrackers Based on Inductively Coupled Plasma Optical Emission Spectrometric Approach (ICP-OES)

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.608-609.1010 ◽

2014 ◽

Vol 608-609 ◽

pp. 1010-1014

Author(s):

Jun Yi Wu

Keyword(s):

Inductively Coupled Plasma ◽

Principal Component ◽

Optical Emission ◽

Titanium Content ◽

High Accuracy ◽

Good Precision ◽

Icp Oes ◽

Inductively Coupled ◽

Pyrotechnic Compositions

Inductively coupled plasma optical emission spectrometric approach (ICP-OES) is used to determine the titanium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element of titanium is commonly found in titanium powder in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that titanium content in pyrotechnics is between 3% to 25%. Concept of this method: considering the weight of the sample is 400mg,constant volume is 1L and the concentration of titanium is between 1 mg/L to 100 mg/L in sample solution, the determination scope of the method for the titanium content would be between 0.25% to 25%.Further experiments proved that the fitting correlation coefficient of titanium calibration curve is 0.9996 or higher, recovery is 100.06%‒105.30%.The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision.

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Effect of Brewing Water on the Antioxidant Capacity of Green Tea Infusion with DPPH Assay

Journal of Chemistry ◽

10.1155/2022/7736117 ◽

2022 ◽

Vol 2022 ◽

pp. 1-8

Author(s):

Qing-Qing Cao ◽

Yan-Qing Fu ◽

Cheng-Bin Zhang ◽

Yan Zhu ◽

Jun-Feng Yin ◽

...

Keyword(s):

Antioxidant Activity ◽

Synergistic Effect ◽

Metal Ions ◽

Antioxidant Capacity ◽

Green Tea ◽

Ph Value ◽

Major Contributor ◽

Dpph Assay ◽

Tea Infusion ◽

Selection Of

Brewing water plays a crucial role in flavor and potential healthy functions of tea infusion. In this study, seven water samples with different physicochemical properties were selected to brew green tea. Results showed that the brewing water with higher minerals level and pH value would reduce the yield of catechins in tea infusion, which in turn caused the decrease of antioxidant activity to a large extent. Besides, it was found that EGCG, as a major contributor to the antioxidant activity of green tea infusion, was influenced differently by different metal ions, among which Ca2+/Mg2+ could enhance the antioxidant activity of EGCG solutions with different concentration through synergistic effect, particularly Ca2+, and the effect was more markable at a higher EGCG concentration. These results offered theoretical direction to the selection of tea brewing water for consumers and gave a new sight to the effects of metal ions on the antioxidant capacity of EGCG.

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Determination of Quality Characteristics, Phenolic Compounds and Antioxidant Activity of Propolis from Southeastern Mexico

Journal of Apicultural Science ◽

10.2478/jas-2021-0008 ◽

2021 ◽

Vol 65 (1) ◽

pp. 109-122

Author(s):

Enrique Sauri-Duch ◽

Cesia Gutiérrez-Canul ◽

Luis F. Cuevas-Glory ◽

Lorena Ramón-Canul ◽

Emilio Pérez-Pacheco ◽

...

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

Geographical Location ◽

Principal Component ◽

Total Phenolic ◽

Dry Extract ◽

Extract Content ◽

The Individual

Abstract The objective of this work was to investigate the variability of physicochemical parameters, phenolic compounds and in vitro antioxidant activity of propolis collected from different apiaries in southeastern Mexico. A high variability was found in the moisture content (1.96–8.26%), ash (0.66–5.50%) and sensory characteristics of raw propolis from southeastern Mexico, but the raw propolis samples met the requirements of the quality regulations. In the same way, most of the ethanolic extracts also complied with the quality regulations. Of all the extracts, PE2 obtained from Santa Cruz showed the highest values for dry extract, content of total phenolic compounds (TPC), total flavonoids (TF) and antioxidant activity (DPPH and ABTS). The content of the individual phenolic compounds varied according to the geographical location of the apiary, but the PE2 extract resulted in the highest pinocembrin and chrysin content. A positive correlation was obtained between TPC and TF with antioxidant activity. Propolis extracts were classified into two groups through principal component analysis (PCA). These results indicate that the apiary location in southeastern Mexico influenced the characteristics of propolis.

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Antioxidant (gallic acid and quercetin) profile of Sumatran wild mangoes (Mangifera spp.): a potential source for antidegenerative medicine

F1000Research ◽

10.12688/f1000research.22380.1 ◽

2020 ◽

Vol 9 ◽

pp. 220

Author(s):

Fitmawati Fitmawati ◽

Esi Resida ◽

Sri Nur Kholifah ◽

Rodesia Mustika Roza ◽

Muhammad Almurdani ◽

...

Keyword(s):

Antioxidant Activity ◽

Gallic Acid ◽

High Performance ◽

Dry Weight ◽

Hplc Method ◽

Flavonoid Compound ◽

The Public ◽

New Findings ◽

Phenolic Analysis

Background: New findings on the potential of wild mangoes from the island of Sumatra as a source of antioxidant helps their conservation effort as it introduces their useful compounds to the public. This study aims to analyze the antioxidant profile and quantification of gallic acid and quercetin content from leaves and bark of Sumatran wild mangoes. Exploration and analysis of phytochemical constituents from 11 Sumatran wild mangoes was performed. Methods: Antioxidant activity of wild mangoes was analysed with 1,1- diphenyl-2-picryl hydroxyl (DPPH), and determination of quercetin and gallic acid content was performed by high performance liquid chromatography (HPLC) method. Total flavonoid and phenolic analysis was also performed. Curve fitting analysis used a linear regression approach. Results: The highest level of antioxidant activity, phenolic compound and flavonoid compound was found in the leaves and bark of Mangifera sp1. (MBS), the bark of M. foetida3 (var. batu) and leaves of M. torquenda, and the bark and leaves of M. sumatrana, respectively. The content of gallic acid in leaves ranged from 5.2270-35.4763 mg/g dry weight. Quercetin content of wild mangoes leaves ranged from 0.76 to 1.47 mg/g dry weight with the lowest value in M. foetida2 (var. manis) and the highest in M. laurina. Conclusion: The results obtained are expected to be useful in supporting the development of antidegenerative drugs from natural ingredients that have potential as immunomodulatory agents.

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Defining a standardized methodology for the determination of the antioxidant capacity: case study of Pistacia atlantica leaves

The Analyst ◽

10.1039/c9an01643k ◽

2020 ◽

Vol 145 (2) ◽

pp. 557-571 ◽

Cited By ~ 2

Author(s):

Ziyad Ben Ahmed ◽

Yousfi Mohamed ◽

Viaene Johan ◽

Bieke Dejaegher ◽

Kristiaan Demeyer ◽

...

Keyword(s):

Antioxidant Activity ◽

Electron Transfer ◽

Hydrogen Atom ◽

Antioxidant Capacity ◽

Hydrogen Atom Transfer ◽

Single Electron ◽

Single Electron Transfer ◽

Pistacia Atlantica

Antioxidant activity can be measured by a variety of methods, that include hydrogen atom transfer (HAT) and single electron transfer (ET) methods.

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Phenolic Composition, Antioxidant Activity, andIn VitroAvailability of Four Different Berries

Journal of Chemistry ◽

10.1155/2016/5194901 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7 ◽

Cited By ~ 22

Author(s):

Javier Marhuenda ◽

María Dolores Alemán ◽

Amadeo Gironés-Vilaplana ◽

Alfonso Pérez ◽

Gabriel Caravaca ◽

...

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

Antioxidant Capacity ◽

Total Phenolic ◽

Phenolic Composition ◽

Total Phenolic Compounds ◽

Anthocyanin Concentration

Polyphenols from berries have proved healthy effects after“in vitro”and“in vivo”studies, such as preventing tumor growing and neurodegenerative and cardiovascular diseases. We compared four different kinds of berries—strawberry, raspberry, blackberry, and blueberry—with the aim to distinguish their phenolic composition, concerning their antioxidant capacity along with their“in vitro”availability. Folin-Ciocalteu method was used for the determination of phenolic compounds, and the antioxidant capacity was measured by ORAC method. Moreover, the determination of anthocyanins was accomplished with an HPLC-DAD. Finally, we carried out an“in vitro”digestion to simulate the gastrointestinal digestion. All berries showed good antioxidant capacity with significant differences, besides high total phenolic compounds. Content of anthocyanins measured by HPLC-DAD varied between the different berries, namely, blackberries and strawberries which showed higher anthocyanin concentration. After“in vitro”digestion, berries showed poor bioavailability of the analysis of anthocyanins (9.9%–31.7%). Availability of total phenolic compounds was higher than anthocyanins (33%–73%). Moreover, strawberries and blackberries presented the less availability grade. Decrease in antioxidant activity measured by ORAC method was about 90% in all berries studied. Therefore, bioavailability of phenolic compounds remains unclear and more correlation between“in vitro”and“in vivo”studies seems to be necessary.

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Integrated FIA/HPLC method for preconcentration and determination of transition metal ions

Chromatographia ◽

10.1007/bf02290233 ◽

1992 ◽

Vol 34 (9-10) ◽

pp. 445-449 ◽

Cited By ~ 12

Author(s):

P. Richter ◽

J. M. Fernández-Romero ◽

M. D. Luque de Castro ◽

M. Valcárcel

Keyword(s):

Transition Metal ◽

Metal Ions ◽

Transition Metal Ions ◽

Hplc Method

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Antioxidants: Terminology, Methods, and Future Considerations

Antioxidants ◽

10.3390/antiox8080297 ◽

2019 ◽

Vol 8 (8) ◽

pp. 297 ◽

Cited By ~ 10

Author(s):

Khiena Brainina ◽

Natalia Stozhko ◽

Marina Vidrevich

Keyword(s):

Antioxidant Activity ◽

Antioxidant Capacity ◽

Activity Concentration ◽

Antiradical Activity ◽

Antioxidative Activity ◽

Antioxidant Power ◽

Trolox Equivalent ◽

Ferric Reducing Antioxidant Power ◽

Quality Diet

Unreliable terminology and incompatible units of antioxidant activity/concentration expression lead to the failure of antioxidant clinical trials, ambiguity of conclusions about the effect of a chosen therapy in medicine and evaluation of food quality, diet, difficulties using information in monitoring the training process in sports, etc. Many different terms (antiradical activity, antioxidant activity, antioxidant capacity, antioxidant power, antioxidant ability) and methods: Trolox equivalent capacity assay (TEAC), Ferric Reducing Antioxidant Power assay (FRAP), Cupric Reducing Antioxidant Capacity assay (CUPRAC), antioxidative activity assay (ABTS), the oxygen radical absorbance capacity (ORAC), and different options of electrochemical ones) proposed for the determination of antioxidants are described. Possible approaches to the development of this field of science and practice are considered.

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