Improved peroxyl radical scavenging TOSC assay to quantify antioxidant capacity using SIFT-MS

Redox Report ◽  
2009 ◽  
Vol 14 (5) ◽  
pp. 197-204 ◽  
Author(s):  
Senti T. Senthilmohan ◽  
Brett M Davis ◽  
Paul F. Wilson ◽  
Murray J. McEwan
2017 ◽  
Vol 12 (1) ◽  
Author(s):  
Maura N. Laus ◽  
Mariagrazia P. Cataldi ◽  
Carlo Robbe ◽  
Tiziana D'Ambrosio ◽  
Maria L. Amodio ◽  
...  

Antioxidant capacity (AC) of quinoa (<em>Chenopodium quinoa</em> Willd. cv. Real) seeds and sprouts obtained after 4 days of seed germination at 20°C and 70% humidity was evaluated using trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays, able to highlight reducing activity and peroxyl radical scavenging capacity, respectively; phenolic content (PC) was also measured. Both TEAC and ORAC assays revealed a significantly higher (about 2- and 2.8-fold, respectively) AC of 4-day-old sprouts compared to seeds; consistently, also PC values of sprouts resulted about 2.6 times higher than seeds. In order to investigate the influence of storage on AC and PC, as well as on vitamin C content (VCC), 4-day-old sprouts were subjected for 7 days at 5°C to three different conditions of controlled atmosphere storage (CAS) compared with air. Interestingly, whatever the CAS conditions, storage of quinoa sprouts up to 7 days induced an increase of AC evaluated in terms of reducing activity by TEAC assay. Consistently, an increase of PC and VCC was measured during storage, positively correlated to TEAC values. Moreover, a decrease of peroxyl radical scavenging activity, measured by ORAC, was observed after 7 days of storage, in accordance with a shift of AC towards the reducing activity component. Overall, these findings indicate that sprouting approach using quinoa may provide highly antioxidant-enriched seedlings that may improve nutritional quality of diet or of functional foods. Interestingly, antioxidant properties of quinoa sprouts may be deeply influenced by storage, able to increase reducing activity by increasing phenols and vitamin C.


Foods ◽  
2019 ◽  
Vol 8 (8) ◽  
pp. 281 ◽  
Author(s):  
Saleha Akter ◽  
Michael E. Netzel ◽  
Ujang Tinggi ◽  
Simone A. Osborne ◽  
Mary T. Fletcher ◽  
...  

Terminalia ferdinandiana (Kakadu plum) is a native Australian plant containing phytochemicals with antioxidant capacity. In the search for alternatives to synthetic preservatives, antioxidants from plants and herbs are increasingly being investigated for the preservation of food. In this study, extracts were prepared from Terminalia ferdinandiana fruit, leaves, seedcoats, and bark using different solvents. Hydrolysable and condensed tannin contents in the extracts were determined, as well as antioxidant capacity, by measuring the total phenolic content (TPC) and free radical scavenging activity using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Total phenolic content was higher in the fruits and barks with methanol extracts, containing the highest TPC, hydrolysable tannins, and DPPH-free radical scavenging capacity (12.2 ± 2.8 g/100 g dry weight (DW), 55 ± 2 mg/100 g DW, and 93% respectively). Saponins and condensed tannins were highest in bark extracts (7.0 ± 0.2 and 6.5 ± 0.7 g/100 g DW). The antimicrobial activity of extracts from fruit and leaves showed larger zones of inhibition, compared to seedcoats and barks, against the foodborne bacteria Listeria monocytogenes, Bacillus cereus, Methicillin resistant Staphylococcus aureus, and clinical isolates of Pseudomonas aeruginosa. The minimum inhibitory concentration and minimum bactericidal concentration in response to the different extracts ranged from 1.0 to 3.0 mg/mL. Scanning electron microscopy images of the treated bacteria showed morphological changes, leading to cell death. These results suggest that antioxidant rich extracts of Terminalia ferdinandiana fruits and leaves have potential applications as natural antimicrobials in food preservation.


Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 48
Author(s):  
Anh Dao Thi Phan ◽  
Maral Seidi Damyeh ◽  
Saleha Akter ◽  
Mridusmita Chaliha ◽  
Michael E. Netzel ◽  
...  

Terminalia ferdinandiana (Kakadu plum), belonging to the family Combretaceae, is endemic to Australia and has a long history of traditional medicinal applications and food cuisine by the Australian Indigenous people. This study investigated the effects of maturity stages on the morphology, physicochemical parameters (total soluble solids (TSS), total acid content (TAC), and pH), soluble sugar profile and antioxidant capacity of Kakadu plum (KP) fruits that were wild harvested from different trees and classified into four different maturity stages (immature to mature). TSS and TAC were determined by standard assays/procedures, main sugars by UHPLC–MS/MS and antioxidant capacity (total phenolic content (TPC) and DPPH free radical scavenging capacity) by spectrophotometry. The results showed that soluble sugars (glucose, sucrose and fructose) ranging from 1.3 to 17.7% dry weight (DW), TSS (17.0–52.7% DW) and TAC (1.3–6.7% DW) increased with maturity. However, antioxidant capacity (TPC in the range of 7.4–21.9% DW and DPPH free radical scavenging capacity from 22 to 76% inhibition at the extract concentration of 20 g·L−1) did not follow the same trend as the one observed for soluble sugars, TSS and TAC. These differences were associated with the tree-to-tree variability as a consequence of the wild harvest condition. This study provides important information to both the KP industry and Indigenous enterprises regarding the selection of the appropriate maturity stage to harvest KP fruit to target for different markets (e.g., low-sugar vs. high-sugar fruit).


2021 ◽  
Vol 2 (5) ◽  
pp. 6608-6618
Author(s):  
Eva Coronel ◽  
Silvia Caballero ◽  
Gabriela Gonzalez ◽  
Miho Sunguino ◽  
Laura Mereles

Los frutos de Anisocapparis speciosa son nativas de la Ecoregión del Gran Chaco, crecen de manera silvestre en todo este territorio, su pulpa y semillas son comestibles y muy apreciadas por las poblaciones indígenas que lo habitan, además de otros usos con propiedades medicinales atribuidas por conocimientos etnobotánicos, pero no se tienen datos sobre la composición de estos frutos regionales y sus potenciales aplicaciones. El objetivo del presente trabajo fue evaluar la composición de la pulpa y semillas de frutos en estado maduro, y el potencial antioxidante en diferentes estadíos de madurez. La composición proximal, el contenido de minerales, vitamina C y solidos solubles se realizaron según metodologías oficiales de la AOAC.  Los fenoles totales se determinaron por el método de Folin Ciocalteau y la capacidad antioxidante total por medio de la inhibición del radical ABTS. Los componentes mayoritarios en pulpa y semillas fueron carhobidratos y fibra alimentaria. La pulpa madura posee un buen contenido de vitamina C (20 mg/100g). El contenido de fenoles y capacidad antioxidante total fue mayor en la pulpa que en la semillas en estados inmaduros. Los frutos de Anisocapparis speciosa pueden representar una buena fuente de carbohidratos, fibra alimentaria, Mg y vitamina C en la dieta. La pulpa y semillas son fuentes de antioxidantes naturales. Estudios futuros sobre métodos postcosecha, almacenamiento y procesamiento serán necesarios para potenciar su uso y re-valorización en el marco de la Seguridad alimentaria en la población regional.   The native Anisocapparis speciosa fruits from Gran Chaco Ecoregion, they grow wild throughout this territory, their edible pulp and seeds are highly appreciated by the indigenous populations that inhabit it, in addition to other uses with medicinal properties attributed by ethnobotanicals knowledge, but there are no data on the composition of these regional fruits and their potential applications. The aims of the present work were to analyze the pulp and seeds composition of fruits in the ripe state, and the antioxidant potential in different stages of maturity. The proximal composition, minerals content, vitamin C and soluble solids were carried out according to official AOAC methodologies. The total phenolics compounds (TPC) by the Folin Ciocalteau method and the total antioxidant capacity by means of the inhibition of the radical ABTS were evaluated. The main components in pulp and seeds were carbohydrates and dietary fiber. The ripe pulp has a good content of vitamin C (20 mg/100g). The content of TPC and total antioxidant capacity (ABTS radical scavenging) was higher in pulp than in the seeds, in immature stages. The Anisocapparis speciosa fruits can represent a good source of carbohydrates, dietary fiber, Mg and vitamin C in the diet of regional populations. The pulp and seeds are sources of natural antioxidants. Future studies on post-harvest, storage and processing methods will be necessary to enhance its use and re-valorization within the Food Security framework.  


2014 ◽  
pp. 41-47
Author(s):  
Judit Homoki ◽  
Andrea Nemes ◽  
Judit Remenyik

The antioxidant capacity of ’Debreceni bőtermő’, ’Újfehértói fürtös’ and ’Érdi bőtermő’ cultivars were determined by FRAP (Ferric Reducing Ability of Plasma), DPPH (1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity) and photochemiluminescence method. In sour cherry, the most antioxidant effects of natural bioactive compounds are anthocyanins. Our results show that the photochemiluminescence method out of applied assays is ratheris suitable to determine the antioxidant capacity of red soft fruits and tart cherries. The correlation is good between the determined anthocyanin concent by this technic and pH-differential spectrophotometry. However, both FRAP and DPPH assays are inaccurate. The anthocyanin composition of ’Debreceni bőtermő’, ’Újfehértói fürtös’ and ’Érdi bőtermő’ ’Csengődi csokros’ sour cherry varieties were analised. There are big differences between the accumulation of anthocyanan compounds of cultivars. ’Csengődi csokros’ produce melatonin in large quantity. On the evidence of the results, we can say that the hungarian sour cherry cultivars are suitable for functional food development.


BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 7933-7953
Author(s):  
Ryan J. Stoklosa ◽  
Renee J. Latona ◽  
Michael J. Powell ◽  
Madhav P. Yadav

Recovered hemicellulose fractions from biorefineries have the potential to improve overall process economics during the production of biofuels or other high value chemicals. A common hemicellulose found in many agricultural feedstocks is arabinoxylan (AX). This work investigated the influence of ferulic and p-coumaric acids on the antioxidant capability of AX hemicellulose recovered from sorghum bran, biomass, and bagasse. Sorghum bagasse and sorghum biomass AX contained the largest quantities of bound ferulic and p-coumaric acids at 13.1 mg/100 g and 6.3 mg/100 g, respectively. Antioxidant performance showed that sorghum bagasse AX hemicellulose produced the best reducing capability, while sorghum biomass and sorghum bran AX hemicellulose performed better as free radical scavengers. A reduction in free radical scavenging, as determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, occurred for sorghum bagasse and sorghum biomass AX hemicellulose at higher polysaccharide concentrations, which was either caused by the solution properties of the AX hemicelluloses or DPPH reaction reversibility in the presence of phenolic compounds with methoxy content. Alternatively, H2O2 scavenging by the AX hemicellulose revealed a dose-dependent response. Although scavenging effect was reduced at higher concentrations, sorghum bagasse AX hemicellulose functioned as having the best antioxidant capacity with respect to total reducing capability.


Author(s):  
Wenny Sinaga

Kedelai adalah produk pangan bernilai gizi tinggi yang banyak dikonsumsi oleh masyarakat Indonesia. Pada penelitian ini, kedelai dimodifikasi dengan cara perkecambahan. Komponen zat gizi akan berubah menjadi senyawa-senyawa yang lebih sederhana selama proses perkecambahan sehingga menjadi lebih mudah dicerna bagi tubuh manusia. Selain itu, perkecambahan juga dapat meningkatkan kapasitas antioksidan. Tujuan dari penelitian ini adalah menentukan kondisi perkecambahan untuk mengoptimalkan kapasitas antioksidan dari biji kedelai varietas Wilis. Hasil penelitian menunjukkan bahwa kondisi terbaik untuk mengoptimalkan kapasitas antioksidan adalah dengan cara perkecambahan pada suhu 25°C selama 15 jam dengan rasio biji kedelai dan air 1:3 tanpa adanya penambahan garam. Kapasitas antioksidan kecambah kedelai var. Wilis pada 100 ppm memiliki radical scavenging activity sebesar 9,69% dengan scavenging ternormalisasi 0,65% dengan total fenol 2,1 mg GAE/g pada biji dan 2,9 mg GAE/g pada kecambah. Dari hasil identifikasi GC-MS ditemukan senyawa-senyawa antioksidan yang terdapat pada biji kedelai dan kecambah kedelai berupa benzoic acid, 2-methoxy-4-vinylphenol, 2,5-dihydroxytoluene, pyrogallol 1,3-dimethyl ether, 2,5-dihydroxytoluene, pyrogallol 1,3-dimethyl ether, hexadecanoic acid methyl ester dan methyl oleate serta terdapat juga senyawa-senyawa antioksidan baru yang muncul setelah proses perkecambahan yaitu neophytadiene, campesterol, stigmasterol, delta-tocopherol dan gamma-tocopherol.  ABSTRACT: Soybean is a high nutrition food product that is largely consumed by Indonesians. In this research, the soybean will be modified by going through the germination process. Complex nutrition would be changed into substances that were more simple during the germination process. Therefore, it would be easier for human to digest it. Moreover, this process might also increase the antioxidant capacity of the soybean itself. The aim of this research is to find out the most suitable germination condition in order to acquire the optimum antioxidant capacity of Wilis variety soybean. The result shows that the best condition to optimize the antioxidant capacity is by performing the germination process at 25°C for 15 hours with soybean to water ratio being 1:3 without any salt addition. The antioxidant capacity of Wilis soybean at 100 ppm has 9,69% of radical scavenging activity, with 0,65% being normalized. The total phenolic compound found in the beans was 2,1 mg GAE/g, whereas 2,9 mg GAE/g were found in the sprout. Based on the GC-MS identification, the antioxidant compounds that are found in both the soybean and sprout are known to be benzoic acid, 2-methoxy-4-vinylphenol, 2,5-dihydroxytoluene, pyrogallol 1,3-dimethyl ether, 2,5-dihydroxytoluene, pyrogallol 1,3-dimethyl ether, hexadecanoic acid methyl ester, and methyl oleate. In addition, there are also several new antioxidant compounds that emerge after the germination process, which are neophytadiene, campesterol, stigmasterol, delta-tocopherol, and gamma-tocopherol. Keywords: Soybean var. Wilis, Sprout, Antioxidant, Water Ratio


Ciencia Unemi ◽  
2016 ◽  
Vol 9 (20) ◽  
pp. 29 ◽  
Author(s):  
Ana Echavarria ◽  
Haydelba D'Armas Regnault ◽  
Nubia Lisbeth ◽  
Lisbeth Matute ◽  
Carmita Jaramillo ◽  
...  

El presente estudio evaluó la capacidad antioxidante de los extractos de dieciséis plantas medicinales: escoba amarga (Parthenium hysterophons), ajenjo (Artemisia absinthium), guarumo (t), chaya (Cnidoscolus chayamansa), borraja (Borago officinalis), balsa (Ochroma sp.), linaza (Linum usitatissimum), hierba Luisa (Cymbopogon citratus), toronjil (Melissa officinalis), buganvilla (Bougainvillea spectabilis), alcachofa (Cynara scolymus), guaviduca (Piper carpunya), altamisa (Ambrosia cumanensis), diente de león (Taxacum officinales), buscapina (Parietaria officinalis) y moringa (Moringa oleifera). Para ello, se usó el método DPPH (radical 1,1-difenil-2-picrilhidrazil); además, se realizaron ensayos de reconocimiento de metabolitos secundarios a fin de obtener los primeros indicios de compuestos de interés fitoquímico. La actividad captadora de radicales libres de los extractos se expresó como valor de IC50 (μg/mL) (cantidad necesaria para inhibir la formación de radicales DPPH en un 50%). El valor bajo de IC50 refleja mejor acción eliminadora de radicales libres. Aunque la mayoría de las muestras evaluadas mostraron buena capacidad antioxidante con este método (DPPH), los ensayos de los extractos hidro-alcohólicos demuestran que la alcachofa (IC50 9,89 μg/mL), moringa (IC50 11,4 μg/mL) y borraja (IC50 14,0 μg/mL) presentaron mayor capacidad antioxidante. Mediante las pruebas químicas de caracterización, se detectó la presencia de flavonoides, taninos, triterpenos, alcaloides y saponinas en la mayoría de las especies analizadas (aproximadamente 56-69%); tan sólo un 20% de las mismas mostró la presencia de polifenoles, glucósidos cianogénicos, lactonas, cumarinas, esteroles y antraquinonas. Según los resultados, se podría considerar a estas plantas como fuentes prometedoras de metabolitos secundarios con actividad antioxidante.  ABSTRACTThis study evaluated the antioxidant capacity of sixteen medicinal plants: Escoba amarga (Parthenium hysterophons), ajenjo (Artemisia absinthium), guarumo (Cecropia obtusifolia), chaya (Cnidoscolus chayamansa), borraja (Borago officinalis), balsa (Ochroma sp.), linaza (Linum usitatissimum), hierba Luisa (Cymbopogon citratus), toronjil (Melissa officinalis), buganvilla (Bougainvillea spectabilis), alcachofa (Cynara scolymus), guaviduca (Piper carpunya), altamisa (Ambrosia cumanensis), diente de León (Taxacum officinales), buscapina (Parietaria officinalis)and moringa (Moringa oleifera). For this, the DPPH (radical 1, 1-difenil-2-picrilhidrazil) method was used; furthermore, recognition assays of secondary metabolites were performed, in order to obtain the first signs of phytochemical compounds of interest. The free radical scavenging activity of the extracts was expressed as IC50 value (g/mL) (necessary amount to inhibit the formation of 50% of DPPH radical). The low value of IC50 reflects better free radical scavenging action. Although most of the samples tested showed good antioxidant capacity with this method (DPPH), tests of hydroalcoholic extracts show that alcachofa (IC50 9.89 mg/mL), moringa (IC50 11.4 mg/mL) and borraja (IC50 14.0 mg/mL) were those with higher antioxidant capacity. Through chemical characterization tests, the presence of flavonoids, tannins, triterpenes, alkaloids and saponins were detected in most of the analyzed species (approximately 56-69%); only 20% of them showed the presence of polyphenols, cyanogenic glycosides, lactones, coumarins, anthraquinones and sterols. According to the results obtained, these plants might be considered as promising sources of secondary metabolites with antioxidant activity.


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