Characterization of antioxidant compounds of red and white rice and changes in total antioxidant capacity during processing

2007 ◽  
Vol 51 (8) ◽  
pp. 1006-1019 ◽  
Author(s):  
Franca Finocchiaro ◽  
Barbara Ferrari ◽  
Alberto Gianinetti ◽  
Chiara Dall'Asta ◽  
Gianni Galaverna ◽  
...  
Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4209
Author(s):  
Anca Becze ◽  
Vanda Liliana Babalau-Fuss ◽  
Cerasel Varaticeanu ◽  
Cecilia Roman

Circular economy principles are based on the use of by-products from one operation as the raw materials in another. The aim of this work is to obtain extracts with high antioxidant capacity and resveratrol content for the superior capitalization of the biomass of Feteasca regala leaves obtained during vineyard horticultural operations in spring. In order to obtain a high-quality extract at an industrial level, an optimal extraction process is needed. Central composite design (CCD) was used for the experiment design, which contained three independent variables: the ratio of extraction solvent to solid matter, temperature (°C) and time (minutes). The evaluation of extracts was done by measuring the total antioxidant capacity of the extracts using photo-chemiluminescent techniques, and the resveratrol content using liquid chromatography. Process optimization was done using response surface methodology (RSM). Minitab software version 17.0 was used for the design of experiments and data analysis. Regression analysis showed that the model predicts 87.5% of the variation for resveratrol and 96% for total antioxidant capacity (TAC). The temperature had the biggest influence on the extraction yield. The optimal operational conditions for the extraction method applied had the following conditions: ratio e/m 2.92; 43.23 °C and 55.4 min. A maximum value of 34,623 µg ascorbic acid equivalent (AAE) /mL total antioxidant capacity and 182.4 µg/mL resveratrol content were obtained when the optimal extraction parameters where used. The values obtained in experiments proved that by using RSM an accurate model can be obtained for extraction of Feteasca regala leaves.


2013 ◽  
pp. 165-169
Author(s):  
Juliana Aparecida de Souza-Sartori ◽  
Adna Prado ◽  
Lucimara Fernanda Veiga ◽  
Nathalia Torres ◽  
Severino Matias de Alencar ◽  
...  

Extraction of antioxidant compounds present in the top leaves of sugarcane at different stages of plant development showed that the most favorable phase for the extraction is the final stage of maturation of the plant. Flavonoid contents (5.98±0.32mg/mL) and relative antioxidant activity (AArel=257.49±16.94%) similar to the initial stage of maturation were found. Active compounds were chromatographically fractionated over silica gel and elution with solvents of increasing polarity. The antioxidant activity towards -carotene, and the sequestering activity of DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals was determined. The fractions which had the highest total antioxidant capacity (TAC) were obtained from the elution of the solvent mixture: chloroform and ethanol. The results indicate that the top leaves of sugarcane are a possible source of bioactive compounds.


2019 ◽  
Vol 27 (1) ◽  
pp. 46-53 ◽  
Author(s):  
Michela Alfieri ◽  
Giovanni Cabassi ◽  
Ephrem Habyarimana ◽  
Fabrizio Quaranta ◽  
Carlotta Balconi ◽  
...  

One hundred and forty-seven sorghum samples, grown in 2015 and 2017, were used to build different near infrared spectroscopic calibration models able to predict total antioxidant capacity, total phenolics, total flavonoids and condensed tannins content. Samples were separated into calibration and validation sets using a nearest neighbours algorithm. The r2pred values ranged from 0.84 (condensed tannins) to 0.95 (total phenolics), whereas the Ratio of Performance to Deviation (RPD) values ranged from 1.9 (total flavonoids) to 3.0 (total phenolics). Comparison of prediction error estimates highlighted the best models with significant differences. Model robustness was tested through a reduction of sample numbers in the calibration set; the highest robustness was found for total antioxidant capacity and total flavonoids. In addition, a partial least squares discriminant analysis model to screen the samples for their tannins level was developed and resulted in good performance; it should be useful to select tannin-free genotypes for the food industry. These models could be used for rapid screening of sorghum breeding genotypes with high antioxidant compounds.


2020 ◽  
Vol 323 ◽  
pp. 126829 ◽  
Author(s):  
Daniel Hinojosa-Nogueira ◽  
Sergio Pérez-Burillo ◽  
José Ángel Rufián-Henares ◽  
Silvia Pastoriza de la Cueva

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Anamaria Hosu ◽  
Claudia Cimpoiu ◽  
Luminita David ◽  
Bianca Moldovan

Cornus species fruits are well known as a rich source of antioxidant compounds responsible for their diverse health benefits. The present study aims to investigate the variation of the total antioxidant capacity of Cornelian cherry (Cornus masL.) fruits during storage, using high-performance thin-layer chromatography (HPTLC) and two spectrophotometric assays based on different mechanisms: the 2,2-azinobis(3-ethylbenzothiazolyne-6-sulphonic acid) radical cation (ABTS+∙) assay and the ferric reducing antioxidant power (FRAP) assay. The fruit extract was stored at room temperature (22°C) for 19 days. No major differences in the total antioxidant capacity were observed during this period, indicating that storage does not have any deleterious effect on the antioxidant properties of the investigated fruits extract. The antioxidant capacity varied between 12.91 and 12.83 µmol Trolox/g fruit as determined by the HPTLC method and from 36.13 to 33.93 µmol Trolox/g fruit as determined by the ABTS assay.


2011 ◽  
Vol 106 (2) ◽  
pp. 254-263 ◽  
Author(s):  
Meng Yang ◽  
Sang-Jin Chung ◽  
Chin Eun Chung ◽  
Dae-Ok Kim ◽  
Won O. Song ◽  
...  

Given the importance of dietary antioxidants in reducing the risks of chronic diseases, the present study aimed to estimate the intake of total antioxidant capacity (TAC) from diet and dietary supplements of US adults. We utilised the US Department of Agriculture flavonoid and proanthocyanidin databases, dietary supplement data and food consumption data of 4391 US adults aged 19+ years in the National Health and Nutrition Examination Survey 2001–2. In order to convert the intake data of individual antioxidant compounds to TAC values, the vitamin C equivalent (VCE) of forty-three antioxidant nutrients measured previously was also applied. Daily TAC averaged 503·3 mg VCE/d (approximately 75 % from diet and 25 % from supplements). The energy-adjusted daily TAC level from diet and supplements was higher in women (except for carotenoids), older adults, Caucasian (except for carotenoids), non-alcohol consumers (for vitamin E and proanthocyanidins), subjects with higher income (except for carotenoids) and higher exercise levels than their counterparts (P < 0·05). TAC was positively associated with daily consumption of fruits and fruit juices, vegetables and vegetable products, beverages, wines and teas (P < 0·001). Teas, dietary supplements, and fruits and fruit juices were the major sources of dietary TAC of the US population (28, 25 and 17 %, respectively), while the contribution of vegetables and vegetable products to TAC was minimal ( < 2 %). The present study indicates that antioxidant intake from various diet and supplements contributes to TAC status. TAC levels are different in sociodemographic subgroups of the US population. The relationship between TAC intake and risks of chronic disease warrants further investigation.


Biosensors ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 108 ◽  
Author(s):  
Cristina Tortolini ◽  
Paolo Bollella ◽  
Rosaceleste Zumpano ◽  
Gabriele Favero ◽  
Franco Mazzei ◽  
...  

A single-use electrochemical screen-printed electrode is reported based on biomimetic properties of nanoceria particles (CeNPs). The developed tool showed an easy approach compared to the classical spectrophotometric methods reported in literature in terms of ease of use, cost, portability, and unnecessary secondary reagents. The sensor allowed the detection of the total antioxidant capacity (TAC) in wine samples. The sensor has been optimized and characterized electrochemically and then tested with antioxidant compounds occurred in wine samples. The electrochemical CeNPs modified sensor has been used for detection of TAC in white and red commercial wines and the data compared to the 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS)-based spectrophotometric method. Finally, the obtained results have demonstrated that the proposed sensor was suitable for the simple and quick evaluation of TAC in beverage samples.


2014 ◽  
Vol 1 (2) ◽  
pp. 58-64
Author(s):  
Gunavathy N ◽  
Subarna A

The chemical characteristics of different forms of Emblica officinalis - fresh amla, sweet amla, dried amla, salted amla and lehyam - were analyzed for total phenol, vitamin C, carbohydrate, fat and total antioxidant capacity. The ash of the respective samples was used to determine the iron, calcium and phosphorus content. Higher percentage of total antioxidant capacity was observed in all the samples, which depends on the concentration of the phenolic compounds. In conclusion it can be stated that the vitamin C content (361.90mg/100g) and iron content (0.012mg/100mg) were higher in fresh form of Emblica officinalis whereas dried amla showed higher level of phosphorus (0.14%), phenolic acids (10%) compared to all other form of Emblica officinalis.


Sign in / Sign up

Export Citation Format

Share Document