scholarly journals Influence of Tea Brewing Parameters on the Antioxidant Potential of Infusions and Extracts Depending on the Degree of Processing of the Leaves of Camellia sinensis

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4773
Author(s):  
Jolanta Kowalska ◽  
Agata Marzec ◽  
Ewa Domian ◽  
Sabina Galus ◽  
Agnieszka Ciurzyńska ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Green Tea ◽  
Epigallocatechin Gallate ◽  
Antioxidant Potential ◽  
Aqueous Extracts ◽  
Polyphenol Content ◽  
Total Polyphenols ◽  
Brewing Process ◽  
Spring Harvest ◽  
Growing Region

The polyphenol content of tea depends on the growing region, harvest date, the production process used, and the brewing parameters. In this study, research was undertaken that included an analysis of the influence of the brewing process parameters on the content of total polyphenols (Folin-Ciocalteu), epigallocatechin gallate (HPLC), and antioxidant activity (against DPPH radicals) of fresh tea shrub leaves grown from Taiwan and of teas obtained from them (oolong, green in bags, and green loose from the spring and autumn harvest). The antioxidant potential was determined in the methanol and aqueous extracts, as well as in infusions that were obtained by using water at 65 or 100 °C and infusing the tea for 5 or 10 min. The highest content of total polyphenols and epigallocatechin gallate was found in green tea extracts from the spring harvest. However, in the case of infusions, the highest content of these compounds was found in green tea in bags. Steaming at 100 °C for 10 min, turned out to be the most favourable condition for the extraction. Oolong tea, brewed at 100 °C for 5 min was characterised by the highest antioxidant activity against stable DPPH radicals.

scholarly journals Total Polyphenols Content and Antioxidant Activity of Different Tea Commercially Produced in Nepal

2013 ◽  
Vol 6 ◽  
pp. 73-79
Author(s):  
Rojeena Shrestha ◽  
Jiwan Pravan Lama ◽  
Kshitij Shrestha
Keyword(s):  
Antioxidant Activity ◽  
Green Tea ◽  
Radical Scavenging ◽  
Kathmandu Valley ◽  
Polyphenol Content ◽  
Total Polyphenols ◽  
Total Polyphenol ◽  
Radical Scavenging Capacity ◽  
Scavenging Capacity ◽  
Different Parts

This study was conducted to assess and compare the total polyphenol content (TPC), antioxidant activity of different tea varieties commercially produced in Nepal. Nine different brands of tea samples, three from each CTC, orthodox and green tea were collected from different parts of Kathmandu valley. TPC was analyzed as per folin-ciocalteu method and antioxidant activity as per DPPH (2, 2-diphenyl-1-picrylhrdrazine) free radical scavenging capacity. The TPC was found to be 4.60, 8.79, 18.20mg of phenol equivalent (PE)/gm of sample in CTC, orthodox and green tea respectively. Green tea Emerald and green tea Kanchanjunga contained the highest level of polyphenol. Antioxidant activity (for 0.36 mg of tea sample) was found to be 25.04, 43.86, and 72.39% for CTC, orthodox and green tea respectively. Moreover, some commercial brands of green tea (Emerald and Kanchanjunga) showed the highest antioxidant activity. The TPC and antioxidant activity of different commercial brands of tea were found to be positively correlated (r=0.97). J. Food Sci. Technol. Nepal, Vol. 6 (73-77), 2010 DOI: http://dx.doi.org/10.3126/jfstn.v6i0.8264

scholarly journals Effect of variety and cultivation technology on phenols and antioxidant activity of sweet and sour cherry

2010 ◽  
Vol 16 (1) ◽  
Author(s):  
A. Sass-Kiss ◽  
M. Tóth-Markus ◽  
H. G. Daood ◽  
D. Bánáti ◽  
J. Nyéki ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Low Temperature ◽  
Sweet Cherry ◽  
Sour Cherry ◽  
Anthocyanin Content ◽  
Total Phenols ◽  
Polyphenol Content ◽  
Total Polyphenols ◽  
Cultivation Technology ◽  
Sweet Cherry Cultivars

The goal of the present work was to compare different sweet and sour cherry cultivars and cultivation methods (bio/integrated) with respect to polyphenol content and antioxidant activity. The concentration of total polyphenols ranged between 880–1050 mg kg-1 of fresh fruit, whereas antioxidant activity expressed as TEAC was found to be between 5.4 and 10.3 mmol kg-1 for the sweet cherry cultivars examined. In case of sour cherry the level of polyphenols ranged between 1283 and 3490 mg/kg fresh edible part of the fruit. Antioxidant activity was recorded between 15–32 mmol kg-1 for the different sour cherry cultivars included in this work. After one-month storage at low temperature, the total phenols and antioxidant activity decreased by 2–40% in the sour cherry cultivars studied. The anthocyanin content in cherry cultivars was less (131–312 mg kg-1) than the135–1893 mg kg-1 found in sour cherries. Anthocyanin level was higher in samples produced under organic farming conditions than in those produced with integrated cultivation.

scholarly journals Wines with Increased Lignan Content by the Addition of Lignan Extracts

2016 ◽  
Vol 34 (No. 5) ◽  
pp. 439-444 ◽  
Author(s):  
Balík Josef ◽  
Híc Pavel ◽  
Kulichová Jana ◽  
Novotná Pavla ◽  
Tříska Jan ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Storage Time ◽  
Red Wine ◽  
White Wine ◽  
Polyphenol Content ◽  
Total Polyphenols ◽  
Total Polyphenol ◽  
Ethanol Extracts ◽  
One Year ◽  
And Storage

Red and white wines [Grüner Veltliner white wine and Blue Limberger (Blaufränkisch) red wine (vintage 2013)] were enriched with lignan hydroxymatairesinol originated from spruce knots. These spruce knots with removed resin were extracted with ethyl alcohol of agricultural origin. Ethanol extracts of lignans were then used to enrich wine sorts. Enriched wines were stored for 13 months. At 2, 6, and 13 months, samples were taken and subjected to a variety of analyses and sensory evaluations. Analyses included 7-hydroxymatairesinol and alpha-conidendrin lignan content, antioxidant activity (as determined by FRAP), total polyphenols, and sensory evaluation. The obtained data were evaluated using the analysis of variance to determine which factors e.g. wine type, quantity of added lignan extracts, additional sugar, method of preservation, and storage time had the most significant influence on lignan content, antioxidant activity and polyphenol content. In all cases the lignan content in the wines was significantly influenced by the addition of lignan extracts. After one year of storage, lignan contents changed only moderately and added lignans were stable in stored wines. Total polyphenol content in wines and the antioxidant activity of wines were significantly influenced by the type of wine (i.e., red or white). The presented method of wine enrichment with lignans opens the door for the production of extra quality wines.

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.

Correlation between theIn Vitro antioxidant activity and polyphenol content of aqueous extracts from bulgarian herbs

2006 ◽  
Vol 20 (11) ◽  
pp. 961-965 ◽  
Author(s):  
Yoana Kiselova ◽  
Diana Ivanova ◽  
Trifon Chervenkov ◽  
Daniela Gerova ◽  
Bistra Galunska ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Aqueous Extracts ◽  
Polyphenol Content

Antioxidant activity and polyphenol content of aqueous extracts from Colombian Amazonian plants with medicinal use

2010 ◽  
Vol 119 (4) ◽  
pp. 1566-1570 ◽  
Author(s):  
Leandro J. Lizcano ◽  
Fadil Bakkali ◽  
M. Begoña Ruiz-Larrea ◽  
José Ignacio Ruiz-Sanz
Keyword(s):  
Antioxidant Activity ◽  
Aqueous Extracts ◽  
Polyphenol Content ◽  
Medicinal Use

scholarly journals Antioxidant activities of aqueous extracts from nine different rose cultivars

2018 ◽  
Vol 7 (2) ◽  
Author(s):  
Hamadia Khurshid ◽  
Syed Mubashar Sabir ◽  
Shahid Iqbal Awan ◽  
Syed Rizwan Abbas ◽  
Muhammad Irshad
Keyword(s):  
Lipid Peroxidation ◽  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Liver Homogenate ◽  
Antioxidant Potential ◽  
Total Phenolic ◽  
Aqueous Extracts ◽  
Dpph Radical ◽  
Rose Petals

Rose petals have been applied as food additives in teas, cakes and flavor extracts. The aim of this research study was to explore and reveal the antioxidant potential of aqueous extracts of rose petals belonging to nine genotypes of rose (wild as well as hybrid). The in vitro antioxidant activities of roses were studied by lipid peroxidation assay, DPPH radical scavenging assay, iron chelation assay, phosphomolybdenum reduction assay and total phenolic and flavonoid contents. The aqueous extract showed inhibition against lipid peroxidation (TBARS), induced by prooxidants (10 µM FeSO4) in mice liver homogenate. The free radical scavenging activities of the extracts were determined by scavenging of the DPPH radical. Extracts also showed metal chelating activities and high antioxidant activity in the phosphomolybdenum assay. The high content of phenolics and flavonoids detected in aqueous extracts may be responsible for the antioxidant activity. Amongst the different rose genotypes, screened, Rosa moschata (musk rose) was found to carry slightly higher antioxidant potential, owing to its higher phytochemical content.

scholarly journals Effect of in vitro gastrointestinal digestion on phenolic compounds and the antioxidant activity of Aloe vera

2020 ◽  
Vol 7 (3) ◽  
pp. 11-25
Author(s):  
Imen Laib ◽  
Farida Kehal ◽  
Nour Elyakine Haddad ◽  
Taous Boudjemia ◽  
Malika Barkat
Keyword(s):  
Antioxidant Activity ◽  
Phenolic Compounds ◽  
Aloe Vera ◽  
Total Phenol Content ◽  
Gastrointestinal Digestion ◽  
Polyphenol Content ◽  
Total Polyphenols ◽  
Total Polyphenol ◽  
Spectrophotometric Methods

AbstractThe aim of this work is to study the effect of digestion on the total polyphenol content, flavonoids and the antioxidant activity of Aloe vera. Total polyphenol contents and flavonoid spectrophotometric methods: The evaluation of the antioxidant activity was carried out by three methods, DPPH, ABTS and CUPRAC. To confirm the results obtained we carried out an analysis by ATR-FTIR. The total phenol content found in the Aloe vera extract studied was 1.3638 mg EAG/100 g, while the content of flavonoids found in the Aloe vera extract studied was 0.690 mg EQ/100 g. The values of total polyphenols and flavonoids decreased under the effect of gastrointestinal digestion. The spectra obtained during the ATR-FTIR analysis show that Aloe vera is rich in phenolic compounds and flavonoids. Intense bands corresponding to O–H bonds, C=C bond, C–H, CO, CH3 and CH2 confirm the presence of these bioactive compounds. For both the DPPH and CUPRAC methods, Aloe vera extract reveals a strong antioxidant activity, which gradually decreases during the oral and gastric phase and then increases after the intestinal digestion. For the ABTS method, the antioxidant activity decreases during the oral phase, increases during the gastric phase and then decreases again during the intestinal phase.

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

Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7616
Author(s):  
Justyna Antoniewicz ◽  
Joanna Kochman ◽  
Karolina Jakubczyk ◽  
Katarzyna Janda-Milczarek
Keyword(s):  
Antioxidant Activity ◽  
Fermentation Process ◽  
Storage Conditions ◽  
Antioxidant Potential ◽  
Soluble Solids ◽  
Total Phenolic ◽  
Fermented Foods ◽  
Polyphenol Content ◽  
Spontaneous Fermentation ◽  
Potential Health

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.

Sign in / Sign up

Export Citation Format

Share Document