scholarly journals VARIATION IN TOTAL POLYPHENOL CONTENT, ANTIOXIDANT POTENTIAL, THEAFLAVIN AND THEARUBIGINS CONTENT OF BOPF GRADE SRI LANKAN BLACK TEAS (Camellia sinensis L.) OF DIFFERENT CLIMATIC ELEVATIONS AND BOPF GRADE COMMERCIALLY AVAILABLE BLACK TEAS IN SRI LANKA

2016 ◽  
Author(s):  
R.S Ratnayake ◽  
◽  
K.K.D.S Ranaweera ◽  
Keyword(s):  
Sri Lanka ◽  
Camellia Sinensis ◽  
Antioxidant Potential ◽  
Sri Lankan ◽  
Polyphenol Content ◽  
Total Polyphenol ◽  
Total Polyphenol Content

scholarly journals Vicia faba hull: A novel source of fibre, and a functional food with antidiabetic properties

2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Viren Ranawana ◽  
Gordon McDougall ◽  
Nicholas Hayward ◽  
Vassilios Raikos
Keyword(s):  
Vicia Faba ◽  
Wheat Bran ◽  
Proximate Composition ◽  
Broad Bean ◽  
Antioxidant Potential ◽  
Agricultural Crop ◽  
Polyphenol Content ◽  
Total Polyphenol ◽  
Total Polyphenol Content ◽  
Intestinal Digestion

AbstractCombinable broad beans (Vicia faba) is a major agricultural crop in Europe with annual production around 1.5 million mt. During its milling the seed testa (hull) is removed and is a significant underutilised secondary product. The aim of this study was to examine the nutritional and functional properties of broad bean hull (BBH), specifically for blood glucose control and as a source of fibre for humans.The proximate composition of BBH was assessed using standard AOAC methods and the phytochemical profile using LC-MS(1). BBH extracts were characterised for total polyphenol content, antioxidant potential (FRAP, TEAC)(2), and effects on α-amylase (AA) and α-glucosidase (AG) enzyme activity(3). Bread containing BBH was developed and assessed for glycaemic potential using a standardised in vitro gastro-intestinal digestion model(4). Wheat bran and acarbose were used as comparators.BBH showed a comparable proximate composition to wheat bran but with higher fibre (49 vs 43 g/100g), and lower carbohydrate (19 vs 23 g/100g) and fat contents (1.3 vs 5 g/100g). LC-MS profiling showed that proanthocyanidins were the predominant phytochemicals in the hull with some minor compounds including flavonols. Total polyphenol content and antioxidant potential (FRAP, TEAC) of BBH was significantly higher than in wheat bran (160.1 vs 12.3 μg Gallic acid/mL, 3877.9 vs 75.5 μM Fe Sulphate, and 0.50 vs 0.19 mM Trolox Eq respectively; P < 0.001). Compared to acarbose BBH showed a significantly higher IC50 for α-amylase inhibition (76.6 vs 4.2 μg/mL), and a significantly lower value for α-glucosidase inhibition (2.7 vs 2175.8 μg/mL)(P < 0.001). The addition of BBH significantly reduced starch digestion in bread during the oral, gastric phases and at 20 and 60 min of intestinal digestion (P < 0.005).Broad bean hull is a good source of non-soluble fibre with potential for increasing fibre contents in foods by up to 15g/100 g. Compared to similar material it is a richer source of polyphenols and antioxidants, retards both α-amylase and α-glucosidase activity and shows potential for reducing the glycaemic potential of foods.The work was funded by the Rural and Environment Science and Analytical Services Division of the Scottish government (RESAS).

scholarly journals Response Surface Optimization for Antioxidant Extraction and Attributes Liking from Roasted Rice Germ Flavored Herbal Tea

Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 125
Author(s):  
Sriwiang Rittisak ◽  
Ratchanee Charoen ◽  
Natthaya Choosuk ◽  
Wanticha Savedboworn ◽  
Wiboon Riansa-ngawong
Keyword(s):  
Antioxidant Activity ◽  
Response Surface ◽  
Antioxidant Potential ◽  
Optimal Time ◽  
Process Conditions ◽  
Extraction Temperature ◽  
Polyphenol Content ◽  
Herbal Tea ◽  
Total Polyphenol ◽  
Total Polyphenol Content

The optimal process conditions when examining the antioxidant potential, total polyphenol content, and attribute liking in roasted rice germ flavored herbal tea were investigated using response surface methodology (RSM). The influence upon the extraction process of time and temperature was assessed using a full factorial design on three levels with two variables (32), involving five central point replicates. Extraction temperature (70 °C, 80 °C, and 90 °C) and extraction time (3 min, 4.5 min, and 6 min) served as independent variables, while the dependent variables were allocated to the regression equation to determine antioxidant activity (R2 = 0.941) along with total polyphenol content (R2 = 0.849), flavor liking score (R2 = 0.758), and overall liking score (R2 = 0.816). Following experimentation, it was determined that the optimal time and temperature conditions to maximize total polyphenol content, antioxidant activity, flavor, and overall liking score were in a range of 86 °C to 90 °C for 3.4 min to 5.9 min. When these conditions were imposed, the antioxidant potential, total polyphenol content, flavor, and overall liking score were >70% for DPPH scavenging activity, >75 mgGAE/g, >6.7 (like moderately), and >6.5 (like moderately), respectively.

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 Antioxidant activity of selected parts of Prunus domestica L. harvested at two ripening stages.

2020 ◽  
Vol 66 (2) ◽  
Author(s):  
Anna Nowak ◽  
Dominika Szatan ◽  
Joanna Zielonka-Brzezicka ◽  
Katarzyna Florkowska ◽  
Anna Muzykiewicz ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Raw Material ◽  
Antioxidant Potential ◽  
Ripening Stage ◽  
Prunus Domestica ◽  
Polyphenol Content ◽  
Fruit Peel ◽  
Total Polyphenol ◽  
Total Polyphenol Content ◽  
Dpph Method

Introduction: Oxidative stress caused by an excess of reactive oxygen species (ROS) is the main reason behind many civilization diseases. The fruits and leaves of Prunus domestica L. contain antioxidants such as vitamins, polyphenols (including flavonoids) and organic acids.The aim of the study was to evaluate the antioxidant activity and total polyphenol content of extracts of leaves and fruits of the plum harvested in 2 ripening phases.Materials and methods: Antioxidative activity was measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) – ABTS methods, and total polyphenol content by Folin–Ciocalteu technique. Extracts in 40%, 70% and 96% (v/v) of ethanol as well as 99.8% (v/v) methanol were used. Ultrasound-assisted extraction was applied for 15, 30 and 60 min.Results: The antioxidant potential of the extracts, measured by DPPH method, was highest for leaf methanolic extracts of plum harvested before ripening (3.83 ±0.01 mg trolox/g of raw material), while for the ABTS method, highest activity was found in the fruit peel extract in methanol (12.89 ±0.04 mg trolox/g raw material). The highest polyphenol levels (5.89 ±0.16, 6.06 ±0.09 and5.76 ±0.13 mg gallic acid/g raw material) were found in the extracts of leaves harvested at fruit ripening stage, prepared in 70% (30 and 60 min) ethanol and 40% ethanol (60 min), respectively.Conclusion: The alcohol based extracts from the leaves and fruit of Prunus domestica L. were characterized by high antioxidant potential, which suggests the possibility of their use as a valuable source of antioxidants. Ethanol seems to be the most appropriate extractant.Keywords: alcohol based extracts; antioxidant activity; Prunus domestica L.; ripening stage; total polyphenol content.

Assessment of Antimicrobial Activity and total Polyphenol Content of Rosa multiflora and Rosa wichuraiana

2019 ◽  
Vol 10 (04) ◽  
pp. 646-650
Author(s):  
Hyeusoo Kim ◽  
Kyeong Won Yun
Keyword(s):  
Antimicrobial Activity ◽  
Ethyl Acetate ◽  
Antimicrobial Agents ◽  
Ethyl Acetate Fraction ◽  
Rosa Multiflora ◽  
Polyphenol Content ◽  
Total Polyphenol ◽  
Water Fraction ◽  
Total Polyphenol Content ◽  
Rosa Species

The fruit of Rosa multiflora has been used as traditional herbal medicine in Asian countries. The present investigation was undertaken to study the antimicrobial activity and total polyphenol content of hexane, ether, ethyl acetate, water fraction of methanol extract of fruit and flower from Rosa multiflora and Rosa wichuraiana. Antimicrobial activity of the mentioned fractions against 3 gram-positive and 4 gram-negative bacteria using disk diffussion method. The measurement of minimal inhibition concentration (MIC) showed that the ethyl acetate fraction of the two Rosa species is the most effective against the tested bacteria. The total polyphenol content of ethyl acetate fraction of the two Rosa species is higher than the other fractions. The results indicate the antimicrobial activity was related with the total polyphenol content and the fruit and flower of the two Rosa species can be considered as a natural source of antimicrobial agents.

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