scholarly journals Implementation of chemometric techniques for evaluation of antioxidant properties of Camellia sinensis extracts

2014 ◽  
Vol 12 (6) ◽  
pp. 700-710 ◽  
Author(s):  
Joanna Ronowicz ◽  
Bogumiła Kupcewicz ◽  
Elżbieta Budzisz
Keyword(s):  
Antioxidant Activity ◽  
Camellia Sinensis ◽  
Antioxidant Properties ◽  
Cation Radical ◽  
Polyphenol Content ◽  
Data Set ◽  
Total Polyphenol ◽  
Total Polyphenol Content ◽  
Radical Method ◽  
Chemometric Techniques

AbstractIn this study, antioxidant properties of commercial green teas and dietary supplements containing Camellia sinensis extracts were evaluated. Extracts were examined using two antioxidant assays (DPPH· radical method and ABTS·+ cation radical method). A Folin-Ciocalteu assay was used to evaluate the total polyphenol content in the extracts. In order to compare and characterize the investigated Camellia sinensis extracts, chemometric techniques based on fingerprint chromatograms, antioxidant activity and total polyphenol content were applied. Application of chemometric methods allowed for reduction of multidimensionality of the data set and grouped the samples into differentiable clusters. The relationship between the antioxidant activity and total polyphenol content was also assessed. The results indicated that extracts with the higher polyphenolic content exhibited the stronger antiradical activity against both DPPH· radicals and ABTS·+ cation radicals. The multivariate calibration technique (such as a tree regression algorithm) can be a useful tool for rapid determining the antioxidant activity of a herbal product based on its fingerprint chromatogram

scholarly journals Changes of antioxidant activity and active compounds content in selected teas

2020 ◽  
Vol 8 (1) ◽  
pp. 91-97
Author(s):  
Barbara Kolodziej ◽  
Sugier Danuta ◽  
Luchowska Katarzyna
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Properties ◽  
Ferric Ions ◽  
Polyphenol Content ◽  
Total Polyphenols ◽  
Total Polyphenol ◽  
Total Polyphenol Content ◽  
Tea Infusions ◽  
Anti Oxidant ◽  
Brewing Time

Our study tested 45 tea infusions classified into five groups (white, green, red, black, and other teas) for the content of total polyphenols and flavonoids, as well as antioxidant properties, by the FRAP and DPPH methods. We examined these parameters after prolongation of the brewing time from 10 to 30 min and overnight storage. The results showed that the capacity of the teas to bind free radicals was differentiated and the amount of anti-oxidant compounds depended on their nature. In terms of antioxidant activity and total polyphenol content, the tested tea types were ranked in the following order: white > green > black > red > other teas (yerba mate > rooibos). Our experiment demonstrated a positive correlation between the polyphenol content and antioxidant activity of the analyzed teas. Also, the DPPH antiradical efficiency was comparable to their ability to reduce ferric ions. The extended brewing time had a significant effect on the antioxidant activity of the infusions and the polyphenolic compounds analyzed therein. In contrast, storage of the infusions for 24 h at room temperature changed their antioxidant activity and affected the total polyphenol content.

scholarly journals In vitro antioxidant activity of honeydew and multifloral types of honey from Serbia

2013 ◽  
pp. 269-277 ◽  
Author(s):  
Zoran Maksimovic ◽  
Nebojsa Nedic
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Properties ◽  
Geographic Origin ◽  
Radical Scavenging ◽  
Colour Intensity ◽  
Polyphenol Content ◽  
Total Polyphenol ◽  
Antioxidant Power ◽  
Total Polyphenol Content ◽  
Ferric Reducing Antioxidant Power

Antioxidant properties of fifteen multifloral and honeydew types of honey from Serbia were assessed by determination of ferric-reducing antioxidant power (FRAP assay) and 2,2- diphenyl-1-picrylhydrazyl free radical scavenging ability (DPPH assay), with respect to their total polyphenol content and colour intensity. The results of this study showed that total polyphenol content, antioxidant activity and colour intensity varied widely among different samples, even within the same type of honey. All investigated parameters were strongly dependent on geographic origin of samples, further emphasizing the importance of their detailed chemical characterisation. In general, polyphenolic content in investigated samples of honey, expressed as catechin equivalents, ranged from 480.2 to 1861.1 mg/kg. The ferric-reducing antioxidant power of honey tended to be lower in brighter and higher in darker samples, varying between 489.6 and 3089.8 ?mol Fe(II) per 100 g of honey. The correlation between the colour and antioxidant activity never reached statistical significance in the case of honeydew type of honey, which was opposed to a trend observed in the case of multifloral honey.

scholarly journals The Quality of Ciders Depends on the Must Supplementation with Mineral Salts

Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3640
Author(s):  
Tomasz Tarko ◽  
Magdalena Januszek ◽  
Aneta Pater ◽  
Paweł Sroka ◽  
Aleksandra Duda-Chodak
Keyword(s):  
Antioxidant Properties ◽  
Control Sample ◽  
Yeast Cells ◽  
Polyphenol Content ◽  
Mineral Salts ◽  
Total Polyphenol ◽  
Total Polyphenol Content ◽  
Yeast Strains ◽  
Magnesium Salts ◽  
The Impact

Providing yeast with the right amount of mineral salts before fermentation can contribute to improving the entire technological process, resulting in a better-quality final product. The aim of this study was to assess the impact of apple must supplementation with mineral salts ((NH4)2SO4, MgSO4, (NH4)3PO4)) on enological parameters, antioxidant activity, total polyphenol content, and the profile of volatile cider compounds fermented with various yeast strains. Rubin cultivar must was inoculated with wine, cider, and distillery or wild yeast strains. Various mineral salts and their mixtures were introduced into the must in doses from 0.167 g/L to 0.5 g/L. The control sample consisted of ciders with no added mineral salts. The basic enological parameters, antioxidant properties, total polyphenol content, and their profile, as well as the composition of volatile compounds, were assessed in ciders. Must supplementation with magnesium salts significantly influenced the use of the analyzed element by yeast cells and was dependent on the yeast strain. In supplemented samples, a decrease in alcohol concentration and total acidity, as well as an increase in the content of extract and total polyphenols, was observed compared to the controls. The addition of ammonium salts caused a decrease in the amount of higher alcohols and magnesium salts, as well as a decrease in the concentration of some esters in ciders.

scholarly journals Total polyphenol content and antioxidant activity of commercial Noni (Morinda citrifolia L.) juice and its components

2010 ◽  
Vol 46 (4) ◽  
pp. 651-656 ◽  
Author(s):  
Adriana Bramorski ◽  
Adriana da Rosa Cherem ◽  
Chaiana Paula Marmentini ◽  
Joseane Torresani ◽  
Tatiana Mezadri ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Capacity ◽  
Grape Juice ◽  
Morinda Citrifolia ◽  
Polyphenol Content ◽  
Total Polyphenol ◽  
Total Polyphenol Content ◽  
Treatment And Prevention

The plant Morinda citrifolia L. (noni) has been the focus of many recent studies due to its potential effects on treatment and prevention of several diseases. However, there are few in vivo and in vitro studies concerning its composition and antioxidant capacity. The aim of the present study was to determine the total polyphenol content (TPC) and antioxidant capacity of a juice commercialized as noni juice, but containing grape, blueberry and noni fruits. Commercial noni juice was compared against its separate constituents of blueberry and grape juice. Folin-Ciocalteu and DPPH• methods were used to determine the concentration of total polyphenol content and antioxidant activity, respectively. Commercial noni juice presented higher values of TPC (91.90 mg of gallic acid/100 mL juice) and antioxidant activity (5.85 mmol/L) compared to its 5% diluted constituents. Concentrated blueberry juice presented higher TPC and antioxidant activity than the other juices analyzed. Considering that the blueberry and grape juices account for only 10% in the composition of commercial noni juice, it can be inferred that these two components contribute significantly to the antioxidant activity. Therefore, additional studies are necessary in order to elucidate the contribution of the noni juice as an antioxidant.

scholarly journals Extraction Process of Polyphenols from Soybean (Glycine max L.) Sprouts: Optimization and Evaluation of Antioxidant Activity

Processes ◽  
2019 ◽  
Vol 7 (8) ◽  
pp. 489 ◽  
Author(s):  
Xuan Tien Le ◽  
Vo Luu Lan Vi ◽  
Tran Quoc Toan ◽  
Long Giang Bach ◽  
Tran Thanh Truc ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Ethanol Concentration ◽  
Dry Weight ◽  
Extraction Process ◽  
Extraction Time ◽  
Extraction Temperature ◽  
Polyphenol Content ◽  
Experimental Conditions ◽  
Total Polyphenol ◽  
Total Polyphenol Content

This research aimed to optimize the total polyphenol content (TPC) extracted from soybean sprout powder under different experimental parameters, including ethanol concentration (60–100% v/v), extraction temperature (40–80 °C), extraction time (15–150 min), material:solvent ratio (1:4–1:10 g/mL), the number extraction cycles (1, 2 and 3 times), the age of sprout (0–7 days), and the used part of the sprout (cotyledon, hypocotyl, or radicle). The obtained results were used in response surface methodology, in combination with a central composite design, to model the total polyphenol content (TPC) with respect to three variables, including ethanol concentration, extraction temperature, and material:solvent ratio. The experimental conditions for optimal recovery of TPC consisted of ethanol concentration of 88% (v/v), extraction temperature of 59 °C, material:solvent ratio of 1:6.5 g/mL, extraction time of 60 min, and 2 cycles of maceration. In addition, for maximal TPC, the sprout should undergo the germination of 5 days and the radicle fraction should be used. Based on the suggested optimum conditions, the obtained and verified TPC was 19.801 mg genistein (GE)/g dry weight (d.w.). The obtained dried extract also exhibited low antioxidant activity.

scholarly journals Comparison of the Total Polyphenol Content and Antioxidant Activity of Chocolate Obtained from Roasted and Unroasted Cocoa Beans from Different Regions of the World

Antioxidants ◽  
2019 ◽  
Vol 8 (8) ◽  
pp. 283 ◽  
Author(s):  
Bogumiła Urbańska ◽  
Jolanta Kowalska
Keyword(s):  
Antioxidant Activity ◽  
Total Content ◽  
Raw Material ◽  
Polyphenol Content ◽  
Cocoa Beans ◽  
Total Polyphenols ◽  
Total Polyphenol ◽  
Total Polyphenol Content ◽  
The World ◽  
High Level

The polyphenol content of cocoa beans and the products derived from them, depend on the regions in which they are grown and the processes to which they are subjected, especially temperature. The aim of the study was to compare the total content of polyphenols and antioxidant activity of chocolates obtained from roasted and unroasted cocoa beans. The chocolates produced from each of the six types of unroasted beans and each of the five types of roasted beans were investigated. The seeds came from Ghana, Venezuela, the Dominican Republic, Colombia and Ecuador. The highest total polyphenol content was determined in cocoa beans originating from Colombia and in the chocolates obtained from them. A higher content of total polyphenols was found in unroasted cocoa beans, which indicates the influence this process had on the studied size. The ability to scavenge free DPPH radicals was at a high level in both the beans and the chocolates produced from them, irrespective of the region where the raw material was grown. A positive correlation between the total polyphenol content and the ability to scavenge free radicals was found.

Effects of Sugar Addition on Total Polyphenol Content and Antioxidant Activity of Frozen and Freeze-Dried Apple Purée

2014 ◽  
Vol 62 (7) ◽  
pp. 1674-1682 ◽  
Author(s):  
Ante Loncaric ◽  
Krunoslav Dugalic ◽  
Ines Mihaljevic ◽  
Lidija Jakobek ◽  
Vlasta Pilizota
Keyword(s):  
Antioxidant Activity ◽  
Polyphenol Content ◽  
Total Polyphenol ◽  
Total Polyphenol Content ◽  
Freeze Dried ◽  
Sugar Addition ◽  
Apple Puree ◽  
Apple Purée
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