The total phenolic content (tpc) and the antioxidant capacity of 12 commercial wines, five red wines, one rosé wine and five white wines were analyzed and compared the results of tpc, p r , dpph and abts + inhibition for different wine types are summarized in table 1 , table 2 and in fig 4 , fig 6 , fig 7 , respectively. Increase or control functionality the total phenolic content and antioxidant activity were measured in wines spiked to different extract concentrations, namely, control and 50, 100, 200, 400, and 800 mg/l, to confirm the dose−response curves in both white and red wines.
The concentration of total phenolics in the white and red grape juice samples varied from 254 to 389 mg/l gallic acid equivalents (gae) (mean=324) and 1407 to 2246 mg/l gae (mean=1760), respectively the red wine contained 3630 mg/l gae. Total phenolic content and total antioxidant capacity the total phenolic content (tpc) and total antioxidant capacity content (tac) of the local wine samples are e büyüktuncel et al. The total phenolic content (tpc) and total antioxidant capacity content (tac) of the local wine samples are e büyüktuncel et al 1663 comparison of total phenolic content and total antioxidant activity in local red wines determined by spectrophotometric methods.
32 determination of total phenolic content figure 1 shows the total phenolic content in the samples of different leafy vegetable and fruit crops grown in tower garden aeroponic systems and in the soil among the leafy vegetables, the highest phenolic content was found in chard (5773 mg gae/g dry wt, in fg and 5345 gae/g dry weight in ag) followed by basil, red kale, and parsley. Total phenolic content: with folin-ciocalteu reagent method using gallic acid as the standard, the average quantity of total phenolic compounds found in white, red and black rice bran extracts were in the ranged from 08931-09884, 10103-10494 and 10810-12239 mg gae mg-1 of extract, respectively as shown in fig 1. There is a risk that polyphenol oxidase (ppo) degrades the phenolic content of the sample therefore there is a need to use ppo inhibitors like potassium dithionite (k 2 s 2 o 4) or to perform experiment using liquid nitrogen or to boil the sample for a few seconds to inactivate the enzyme.
Average total polyphenol content measured by the folin method is 216 mg/100 ml for red wine and 32 mg/100 ml for white wine the content of phenols in rosé wine (82 mg/100 ml) is intermediate between that in red and white wines. The content of phenolic compounds (free and total) determined by the fc method for the different analyzed wines is shown in table 1 the total polyphenol content in red wine was significantly higher than in rosé and white wine (p 005 for both cases) all red wines had phenolic concentrations higher than 1500 mg/l. To examine the total phenolic content, flavonoid concentration and antioxidant activity the yield of extract obtained from 10 g of dry plant material was measured for each extract (table. The content of the unknown phenols is then expressed as equivalents of the appropriate standard some methods for quantification of total phenolic content are based on colorimetric measurements total phenols (or antioxidant effect) can be measured using the folin-ciocalteu reaction results are typically expressed as gallic acid equivalents (gae. Here, the effects of baking and cooking processes were examined on total phenolic content (tpc), total flavonoid content (tfc) and ferric-reducing ability of plasma antioxidant activity (frap aa) of red and yellow quinoa seeds.
Total phenolic content and antioxidant activity of red and yellow quinoa (chenopodium quinoa willd) seeds as affected by baking and cooking conditions. Since the phenolic compounds in wine combats these negative effects and originate from the grape itself the focus of this study was the total phenolic content in red and white grape juice measured in gallic acid equivalentsshow more content.
Total phenolic content of grape juice using visible spectrophotometry abstract the health benefits of red wine are well known and consumption has been encouraged more over the years because of the populations increasing obesity rates and the inherent complications thereof including coronary heart disease and high blood pressure. Red quinoa seeds, have been found to have significantly higher levels of tpc (total phenolic content), tfc (total flavonoid content) and frap (ferric reducing antioxidant potential) than yellow quinoa seeds and thus can be helpful in prevention or management o f degenerative diseases associated with free radical damage (yael brend et al, 2012.
253 total phenolic content the total phenolics of the extracts were determined using the folin and ciocalteu reagent, following the method described by singleton and rossi with slight modifications sample and standard readings were made using a spectrophotometer (cary 50 bio uv-vis spectrophotometer, varian) at 765 nm against the reagent blank. Relationship between antioxidant capacity and total phenolic content of red, ros and white wines article (pdf available) in food chemistry 105(1):204-214 december 2007 with 110 reads.