scholarly journals A Simple Minimized System Based on Moving Drops for Antioxidant Analysis Using a Smartphone

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5744
Author(s):  
Sutasinee Apichai ◽  
Kajorngai Thajee ◽  
Thanawat Pattananandecha ◽  
Chalermpong Saenjum ◽  
Kate Grudpan
Keyword(s):  
Antioxidant Capacity ◽  
Color Change ◽  
Positive Control ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Colorimetric Determination ◽  
Scavenging Activity ◽  
Detection Zone ◽  
Significant Difference ◽  
Trolox Equivalent

In this paper, a novel antioxidant analysis is proposed using a simple minimized device based on moving drops as solution handling and a smartphone as a detector. This approach is based on the colorimetric determination of the scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•), expressed as the half-maximal inhibitory concentration (IC50), vitamin C equivalent antioxidant capacity (VCEAC), and Trolox equivalent antioxidant capacity (TEAC). A small drop of the positive control or the samples moves by eluting an ethanol drop down by the force of gravity to react with a DPPH• drop in the detection zone. The color change of DPPH• is monitored by a smartphone camera, and the color signals are processed using Adobe Photoshop software. The magenta-to-yellow ratio was successfully applied to evaluate the percentage of DPPH• inhibition with no significant difference compared with the reference spectrophotometric method at a confidence level of 95%. The total phenolic content (TPC) was measured using the Folin–Ciocalteu assay. An application to Miang (fermented tea leaf extract) showed the consonant relationship between the scavenging activity of DPPH• and TPC.

scholarly journals Determination of Flavonoid and Proanthocyanidin Profile of Hungarian Sour Cherry

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3278 ◽  
Author(s):  
Andrea Nemes ◽  
Erzsébet Szőllősi ◽  
László Stündl ◽  
Attila Biró ◽  
Judit Homoki ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Sour Cherry ◽  
Fresh Fruit ◽  
Water Soluble ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Antioxidant Power ◽  
Trolox Equivalent

Hungarian sour cherries (SC) are excellent source of anthocyanin (concentrations (100–300 mg in 100 g fresh fruit) and melatonin (0.15 mg in 100 g fresh fruit), but other flavonoid derivatives also can be isolated by aqueous alcoholic extraction. We have developed a new process for extracting non-extractable procyanidines bound to the membrane, proteins, and fibers. These compounds were seperated with UHPLC-MS methods, and the structure of individual components were identified on the basis of their mass fragmentation spectra. The antioxidant capacity of soluble and non-soluble antioxidants were measured with ferric reducing antioxidant power (FRAP), 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity (DPPH), trolox equivalent antioxidant capacity (TEAC) assays, and compared to the new measurement methods of water-soluble antioxidant capacity (ACW), lipid-soluble antioxidant capacity (ACL). Furthermore, total phenolic content (TPC) and total procyanidin content (PAC) were determinated. As a result of our investigation, we found that the solvent combination, where in the first step is water–ethanol (1:1), then 100% ethanol were suitable for the extraction of the extractable antioxidants. However, the chemiluminescence method that is based on the elimination of the superoxide radical is more accurate than other colorimetric methods which measure antioxidant capacity.

scholarly journals Quality Parameters of Juice Obtained from Hydroponically Grown Tomato Processed with High Hydrostatic Pressure or Heat Pasteurization

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Maja Jeż ◽  
Wioletta Błaszczak ◽  
Kamila Penkacik ◽  
Ryszard Amarowicz
Keyword(s):  
Hydrostatic Pressure ◽  
Antioxidant Capacity ◽  
High Hydrostatic Pressure ◽  
Storage Period ◽  
Quality Parameters ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Microbial Count ◽  
Antioxidant Power ◽  
Trolox Equivalent

The effect of processing such as high hydrostatic pressure (HHP) (400-600 MPa/15 min) or low pasteurization temperature (LPT) (74°C/2 min) or high pasteurization temperature (HPT) (90°C/1 min) on selected quality parameters of juice obtained from hydroponically cultivated beef tomatoes was investigated. The total polyphenols content (TPC), total phenolic index (TPI), Trolox equivalent antioxidant capacity (ABTS) and ferric reducing antioxidant power (FRAP) were analysed in the fresh and processed juices stored for 0, 7 and 14 days. What is more, colour parameters (L∗,a∗,b∗,∆E), the activity of polyphenol oxidase (PPO) and peroxidase (POD) and microbial stability were also analyzed following the juices storage. Among all the tested samples, the juice exposed to 600 MPa for 15 min showed superior quality. Samples treated with 600 MPa for 15 min and stored for 0, 7 and 14 days had high TPC, TPI, ABTS, FRAP and a∗ values. As demonstrated, these tested samples at the end of the storage period retained 90% and 95% of their polyphenol content and antioxidant capacity, respectively. As in the case of pasteurization, juice processing at 600 MPa for 15 min clearly reduced the activity of food-spoiling enzymes (PPO, POD) as well as the microbial count. The obtained results showed that TPC was significantly and positively correlated with TPI, ABTS and FRAP parameters.

scholarly journals Phytochemical Composition and Antioxidant Capacity of 30 Chinese Teas

Antioxidants ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 180 ◽  
Author(s):  
Guo-Yi Tang ◽  
Cai-Ning Zhao ◽  
Xiao-Yu Xu ◽  
Ren-You Gan ◽  
Shi-Yu Cao ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
High Performance ◽  
Food Additives ◽  
Water Soluble ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Antioxidant Compounds ◽  
Antioxidant Power ◽  
Phenolic Contents ◽  
Trolox Equivalent

Tea has been reported to prevent and manage many chronic diseases, such as cancer, diabetes, obesity, and cardiovascular diseases, and the antioxidant capacity of tea may be responsible for these health benefits. In this study, the antioxidant capacities of fat-soluble, water-soluble, and bound-insoluble fractions of 30 Chinese teas belonging to six categories, namely green, black, oolong, dark, white, and yellow teas, were systematically evaluated, applying ferric-reducing antioxidant power and Trolox equivalent antioxidant capacity assays. In addition, total phenolic contents of teas were determined by Folin–Ciocalteu method, and the contents of 18 main phytochemical compounds in teas were measured by high-performance liquid chromatography (HPLC). The results found that several teas possessed very strong antioxidant capacity, and caffeine, theaflavine, gallic acid, chlorogenic acid, ellagic acid, and kaempferol-3-O-glucoside, as well as eight catechins, were the main antioxidant compounds in them. Thus, these teas could be good natural sources of dietary antioxidants, and their extracts might be developed as food additives, nutraceuticals, cosmetics, and pharmaceuticals.

scholarly journals Electrochemical Determination of Antioxidant Capacity of Traditional Homemade Fruit Vinegars Produced with Double Spontaneous Fermentation

2021 ◽  
Vol 9 (9) ◽  
pp. 1946
Author(s):  
Maja Chochevska ◽  
Elizabeta Jančovska Seniceva ◽  
Sanja Kostadinović Veličkovska ◽  
Galaba Naumova-Leţia ◽  
Valentin Mirčeski ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Capacity ◽  
Physicochemical Characterization ◽  
Acetic Acid Bacteria ◽  
Electrochemical Determination ◽  
Raw Material ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Spontaneous Fermentation ◽  
Trolox Equivalent

In the current study, the antioxidant activity of traditional homemade fruit vinegars (HMV) was estimated by measuring the rate of homogeneous redox reaction with 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical cation (ABTS•+) using cyclic voltammetry. The antioxidant capacity of six HMV produced using traditional methods and the physicochemical characterization were measured in different vinegar production steps throughout a double spontaneous fermentation process, i.e., without any addition of yeasts or acetic acid bacteria. Their antioxidant capacity was compared with seven fruit commercial vinegars (ComV). Furthermore, the antioxidant capacity was independently measured with the TEAC (Trolox equivalent antioxidant capacity) assay, aiming at correlating with the electrochemical experimental data. Obtained results from both methods, the electrochemical and TEAC assays, interestingly indicated that all HMV have at least 10 times higher antioxidant activity than ComV. Furthermore, the large range of values for antioxidant capacity in samples of commercial vinegars from apples attested the importance of the raw material quality and technological procedures. The positive correlation between total phenolic content and antioxidant capacity measured by the two type of assays indicated that rose hip homemade vinegar (HMV5) has the highest antioxidant capacity. In contrast, the lowest levels of phenolic compounds and antioxidant capacity were found in apple and persimmon homemade vinegars (HMV1 and HMV6, respectively) which indicated that the type of fruit is crucial towards the production of high-quality vinegars. In this way, the use of traditional processes for the production of fruit vinegars proved to be very promising in terms of producing differentiated vinegars and, concomitantly, reaching high levels of health-promoting antioxidant capacities.

scholarly journals Serbian aromatized wine “Bermet”: Electrochemical, chemiluminescent and spectrophotometric determination of antioxidant activity

2020 ◽  
Vol 85 (4) ◽  
pp. 517-529
Author(s):  
Stanislava Gorjanovic ◽  
Ferenc Pastor ◽  
Sofia Loupassaki ◽  
Mile Veljovic ◽  
Predrag Vukosavljevic ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Integrated Approach ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Equal Weight ◽  
Antioxidant Power ◽  
15Th Century ◽  
Traditional Procedure ◽  
Trolox Equivalent ◽  
Ferric Reducing Antioxidant Power

Serbian aromatized wine ?Bermet? from grapes grown on Fruska Gora Mountain has been in production since the 15th century. Ten commercial Bermets produced according to the traditional procedure by different manufacturers, and six prepared within the scope of this study were assessed for antioxidant (AO) activity using electrochemical, chemiluminescent and spectrophotometric AO assays. Direct current polarographic assay based on the decrease of anodic current of [hydrogen(peroxido)(1-)]hydroxidomercury(II) complex formation in alkaline H2O2 solution at potential of mercury oxidation, chemiluminescent H2O2 scavenging assay, as well as commonly used spectrophotometric assays (2,2?-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) based Trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1- picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP)) were used. Total phenolic content (TPC) was determined by Folin?Ciocalteu assay. The results obtained were correlated using regression analysis, ANOVA and F-test. An integrated approach to AO capacity determination allowed a more comprehensive comparison between samples. The approach is based on the introduction of the relative antioxidant capacity index, calculated by assigning each AO assay equal weight, and by PCA analysis. In addition, the introduction of phenolic antioxidant coefficients, calculated as the ratio between individual AO capacity and TPC, enabled a better understanding of their relation.

scholarly journals Antioxidant capacity of Lathyrus sativus seeds

2020 ◽  
Vol 11 ◽  
Author(s):  
Wojciech Rybiński ◽  
Magdalena Karamać ◽  
Michał Janiak ◽  
Andreas Börner ◽  
Natalia Płatosz ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Antioxidant Capacity ◽  
Phenolic Acids ◽  
Total Phenolics ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Grass Pea ◽  
Phenolic Contents ◽  
Trolox Equivalent ◽  
Pea Seeds

Grass pea seeds of 30 varieties from Poland, Slovakia, Czech, Russia, Ukraine, Hungary, Bulgaria, India, Iran, Tunisia, Ethiopia, Canada, and Chile were investigated. Phenolic compounds were extracted from seeds into 80% (v/v) methanol. The total phenolics compounds content of the extracts was determined using Folin-Ciocalteu’s phenol reagent. The antioxidant activity was determined using ABTS and FRAP assays. Total phenolic contents ranged from 2.74 to 10.7 mg/g extract and from 35.9 to 144.7 mg/100 g seeds. The extracts and seeds were characterized using Trolox equivalent antioxidant capacity values of 0.014–0.060 mmol Trolox/g extract and 0.188–0.866 mmol Trolox/100 g seeds, and FRAP values of 0.188–0.866 mmol Fe2+/g extract and 0.541–1.398 Fe2+/100 g seeds. The total phenolics content of grass pea extract was correlated with the results of the ABTS (r = 0.854) and FRAP (r = 0.958) assays. A similar correlation existed between the results of both assays (r = 0.890). Phenolic acids were the dominant phenolic compounds of two cultivars of grass pea. Syringic and sinapic acids had the highest amounts while ferulic, p-hydroxybenzoic, protocatechuic, and p-coumaric acids were present in much lower quantitie. Phenolic acids were present in the form of free compounds, esters, and glycosides.

scholarly journals Evaluation of total phenolic content, antioxidant activity, germination power, and yield of pigeon pea (Cajanus cajan) sprouts elicited using various Naalginate levels with different elicitation duration

Food Research ◽  
2021 ◽  
Vol 5 (S2) ◽  
pp. 91-97
Author(s):  
S. Ariviani ◽  
K.C. Hapsari ◽  
G. Fauza ◽  
D. Ishartani ◽  
W. Atmaka ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Capacity ◽  
Total Phenolic Content ◽  
Cajanus Cajan ◽  
Phenolic Content ◽  
Pigeon Pea ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Antioxidant Power ◽  
Trolox Equivalent

This study was aimed to investigate the total phenolic content and antioxidant activity of elicited pigeon pea (Cajanus cajan) sprouts prepared using various Na-alginate concentrations at different elicitation durations. The germination power and yield of the sprouts were also examined. Elicitation proved capable to improve the antioxidant capacity of legumes sprouts but the yield and germination rates were decreased due to the elicitation stress. In this study, elicitation conducted by immersing pigeon pea seeds in Na -alginate solutions (250, 300, and 350 ppm) for various duration (16, 20, and 24 hrs). The seeds were then germinated for 48 hrs to produce Na-alginate elicited pigeon pea sprouts. The results showed that the total phenolic content (TPC) and antioxidant activity (Trolox equivalent antioxidant capacity, TEAC, and Ferric reducing antioxidant power, FRAP) of elicited pigeon pea sprouts were significantly increased along with the increasing elicitation duration in all Na-alginate levels. The higher Na-alginate levels produce a higher level of TPC, TEAC, and FRAP values. On the other hand, germination power and the yield of the sprouts were significantly decreased along with increasing Na-alginate levels and elicitation duration. Elicitation using 350 ppm Na-alginate with an elicitation duration of 24 hrs produces elicited pigeon pea sprouts with the highest TPC and antioxidant activity, but lowest germination power and yield. These results have an important consequence in developing an elicitation technique to improve the antioxidant capacity of leguminous.

scholarly journals Development and Optimization of Djulis Sourdough Bread Fermented by Lactic Acid Bacteria for Antioxidant Capacity

Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5658
Author(s):  
Hung-Yueh Chen ◽  
Chang-Wei Hsieh ◽  
Pin-Cheng Chen ◽  
Shin-Pin Lin ◽  
Ya-Fen Lin ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Antioxidant Capacity ◽  
Ph Value ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Native Plant ◽  
Sourdough Bread ◽  
Trolox Equivalent ◽  
Valuable Product

This study developed a nutritionally valuable product with bioactive activity that improves the quality of bread. Djulis (Chenopodium formosanum), a native plant of Taiwan, was fermented using 23 different lactic acid bacteria strains. Lactobacillus casei BCRC10697 was identified as the ideal strain for fermentation, as it lowered the pH value of samples to 4.6 and demonstrated proteolysis ability 1.88 times higher than controls after 24 h of fermentation. Response surface methodology was adopted to optimize the djulis fermentation conditions for trolox equivalent antioxidant capacity (TEAC). The optimal conditions were a temperature of 33.5 °C, fructose content of 7.7%, and dough yield of 332.8, which yielded a TEAC at 6.82 mmol/kg. A 63% increase in TEAC and 20% increase in DPPH were observed when compared with unfermented djulis. Subsequently, the fermented djulis was used in different proportions as a substitute for wheat flour to make bread. The total phenolic and flavonoid compounds were 4.23 mg GAE/g and 3.46 mg QE/g, marking respective increases of 18% and 40% when the djulis was added. Texture analysis revealed that adding djulis increased the hardness and chewiness of sourdough breads. It also extended their shelf life by approximately 2 days. Thus, adding djulis to sourdough can enhance the functionality of breads and may provide a potential basis for developing djulis-based functional food.

scholarly journals ANTIOXIDANT CAPACITY AND TOTAL PHENOL CONTENT OF HYPTIS SPP., P. HEPTAPHYLLUM, T. PANAMENSIS, T. RHOIFOLIA, AND OCOTEA SP.

2016 ◽  
Vol 44 (2) ◽  
pp. 28-33 ◽  
Author(s):  
Geovanna Tafurt García ◽  
Luisa Jiménez Vidal ◽  
Ana Calvo Salamanca
Keyword(s):  
Antioxidant Capacity ◽  
Phenolic Content ◽  
Antioxidant Activities ◽  
Colorimetric Assay ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Total Phenol Content ◽  
Total Antioxidant ◽  
Trolox Equivalent ◽  
Highly Correlated

<p>In this work, the possible correlation between the antioxidant activities and the Total Phenolic Content (TPC) and chemical composition of Lamiaceae (<em>H. conferta, H. dilatata, H. mutabilis, H. suaveolens</em>), Burseraceae (<em>P. heptaphyllum, T. rhoifoila, T. panamensis</em>),<em> </em>and Lauraceae (<em>Ocotea </em>sp.) were evaluated. The Trolox Equivalent Antioxidant Capacity or the Total Antioxidant Activity (TAA) was determined by using a colorimetric assay with the ABTS radical cation, Effective Concentration (EC<sub>50</sub>) was evaluated with the DPPH radical, and the TPC was established by the Folin-Ciocalteu method, for ethanolic extracts obtained by cold maceration and evaporation to dryness. Both the TAA and the EC<sub>50</sub> were highly correlated with the TPC. The barks of <em>T. rhoifolia</em> and<em> T. panamensis</em> demonstrated the highest antioxidant capacities. The Burseraceae spp. exhibited the highest TPC, and the Lamiaceae (<em>Hyptis</em> spp.) demonstrated the lowest TPC.</p>

scholarly journals Biomarker: Trolox equivalent antioxidant capacity and telomere length of Thai elderly people with frailty

2019 ◽  
Author(s):  
Jetsada Ruangsuriya ◽  
Penprapa Siviroj ◽  
Pisittawoot Ayood ◽  
Krongporn Ongprasert ◽  
Navakoon Kaewtunjai ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Telomere Length ◽  
Cholesterol Level ◽  
Elderly People ◽  
Adverse Outcomes ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Albumin Concentration ◽  
Frailty Phenotype ◽  
Significant Difference ◽  
Trolox Equivalent

Introduction: Thailand has a rapidly aging population; assessing frailty earlier with biochemical markers could identify many adverse outcomes such as disability, hospitalization, and death. We aimed to examine the correlation between Trolox equivalent antioxidant capacity (TEAC), thiobarbituric acid reactive substances (TBARS), and telomere length and frailty for elderly people in Northern Thailand. Methods: A cross-sectional study was performed between May 2017 and March 2018 with a total of 350 elderly aged 60 and older for frailty phenotype assessment by five frailty criteria including unintentional weight loss, exhaustion, slowness, low physical activities, and grip strength weakness. Twenty-eight subjects in both the frailty and non-frailty groups were analyzed for basic clinical parameters, including plasma TEAC, TBARS, and telomere length. Results: Alanine aminotransferase activity, albumin concentration, cholesterol level, and telomere length were significantly low in the frailty group. The albumin level, TEAC, and telomere length were significantly higher between the ages of 60 and 75 years compared to those with non-frailty over 75 years of age. Likewise, albumin and cholesterol levels were significantly higher in the frailty group aged 60–75 years. Albumin concentration, cholesterol level, TEAC, and telomere length were significantly higher in the non-frailty group when compared to the frailty group aged 60–75 years, but no significant difference was found among these biochemical parameters of frailty and non-frailty whose age was above 75 years. Conclusion: The reduction of albumin concentration, cholesterol level, TEAC, and telomere length supports the underlying mechanism of frailty screened by the frailty phenotype tool in a specific age range. However, further analyses with multi-parameters must be validated before the application in clinical diagnosis for frailty.

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