Aroxyl-Radical-Scavenging Rate Increases Remarkably under the Coexistence of α-Tocopherol and Ubiquinol-10 (or Vitamin C): Finding of Synergistic Effect on the Reaction Rate

2013 ◽  
Vol 117 (28) ◽  
pp. 8378-8391 ◽  
Author(s):  
Kazuo Mukai ◽  
Aya Ouchi ◽  
Saori Nakaya ◽  
Shin-ichi Nagaoka
Keyword(s):  
Vitamin C ◽  
Synergistic Effect ◽  
Reaction Rate ◽  
Radical Scavenging

scholarly journals Comparative Assessment of the Basic Chemical Composition and Antioxidant Activity of Stevia rebaudiana Bertoni Dried Leaves, Grown in Poland, Paraguay and Brazil—Preliminary Results

2021 ◽  
Vol 11 (8) ◽  
pp. 3634
Author(s):  
Teresa Leszczyńska ◽  
Barbara Piekło ◽  
Aneta Kopeć ◽  
Benno F. Zimmermann
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Vitamin C ◽  
Dietary Fiber ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Stevia Rebaudiana ◽  
Steviol Glycosides ◽  
Total Polyphenols ◽  
Stevia Rebaudiana Bertoni

This study compares the content of basic nutrients (proteins, fats, digestible carbohydrates, dietary fiber and ash), steviol glycosides, selected antioxidants (vitamin C, total polyphenols) and antioxidant activity in dried leaves of Stevia rebaudiana Bertoni cultivated in Poland, Paraguay and Brazil and available in the direct sale. The basic chemical composition was determined by standard AOAC (Association of Official Analytical Chemists) methods. Content of steviol glycosides was determined by the UHPLC-UV chromatographic method. Total polyphenols content was expressed as gallic acid equivalent (GAE) and catechins equivalent (CE). Antioxidant activity was measured as ABTS●+ free radical scavenging activity. Dried leaves of S. rebaudiana grown in Poland had significantly higher contents of dietary fiber, and lower protein and ash content, compared to those derived from Paraguay and Brazil. The former had, however, considerably higher contents of total steviol glycosides, stevioside and rebaudioside D, compared to the remaining two plants. In the Paraguay-derived dried leaves, the content of rebaudioside A, C, E and rubusoside was found to be significantly lower. Dried leaves of S. rebaudiana Bertoni, cultivated in Poland, contained substantially more vitamin C and a similar content of total polyphenols, compared to those from Brazil and Paraguay. The examined material from Brazil and Paraguay plantations showed similar antioxidant activity, while that obtained from Polish cultivation was characterized by a significantly lower value of this parameter.

scholarly journals Synergistic Effect of Nanophotocatalysis and Nonthermal Plasma on the Removal of Indoor HCHO

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Yuanwei Lu ◽  
Dinghui Wang ◽  
Yuting Wu ◽  
Chongfang Ma ◽  
Xingjuan Zhang ◽  
...  
Keyword(s):  
Synergistic Effect ◽  
Indoor Air ◽  
Photocatalytic Oxidation ◽  
Reaction Rate ◽  
Nonthermal Plasma ◽  
Pollutant Removal ◽  
Pollutant Concentration ◽  
Air Purification ◽  
Plate Electrode ◽  
Air Treatment

Photocatalysis is an effective method of air purification at the condition of a higher pollutant concentration. However, its wide application in indoor air cleaning is limited due to the low level of indoor air contaminants. Immobilizing the nanosized TiO2particles on the surface of activated carbon filter (TiO2/AC film) could increase the photocatalytic reaction rate as a local high pollutant concentration can be formed on the surface of TiO2by the adsorption of AC. However, the pollutant removal still decreased quickly with the increase in flow velocity, which results in a decrease in air treatment capacity. In order to improve the air treatment capacity by the photocatalytic oxidation (PCO) method, this paper used formaldehyde (HCHO) as a contaminant to study the effect of combination of PCO with nonthermal plasma technology (NTP) on the removal of HCHO. The experimental results show that HCHO removal is more effective with line-to-plate electrode discharge reactor; the HCHO removal and the reaction rate can be enhanced and the amount of air that needs to be cleaned can be improved. Meanwhile, the results show that there is the synergistic effect on the indoor air purification by the combination of PCO with NTP.

Frutos silvestres de Anisocapparis speciosa “pajagua naranja” composición proximal, minerales y potencial antioxidante

2021 ◽  
Vol 2 (5) ◽  
pp. 6608-6618
Author(s):  
Eva Coronel ◽  
Silvia Caballero ◽  
Gabriela Gonzalez ◽  
Miho Sunguino ◽  
Laura Mereles
Keyword(s):  
Vitamin C ◽  
Antioxidant Capacity ◽  
Dietary Fiber ◽  
Total Antioxidant Capacity ◽  
Radical Scavenging ◽  
Natural Antioxidants ◽  
Indigenous Populations ◽  
Soluble Solids ◽  
Gran Chaco ◽  
Total Antioxidant

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.  

scholarly journals In vitro antioxidant and antidiarrheal activities of aqueous and n-hexane extracts of Cucurbita maxima seed in castor oil-induced diarrheal rats

2022 ◽  
Author(s):  
Habibu Tijjani ◽  
Adamu Matinja ◽  
Marwanatu Yahya ◽  
Emmanuel Aondofa ◽  
Akibu Sani
Keyword(s):  
Vitamin C ◽  
Aqueous Extract ◽  
Castor Oil ◽  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Seed Extract ◽  
Hexane Extract ◽  
Cucurbita Maxima ◽  
Seed Extracts

Diarrhea is a common health complaint occurring with mild, temporary conditions to a potentially life-threatening condition. <i>Cucurbita maxima</i> (Cucurbitaceae) seed is reportedly used traditionally for the treatment of diarrheal and thus this study aimed to evaluate the in vitro antioxidants, total tannins, phenolics contents, and antidiarrheal potentials of <i>n</i>-hexane and aqueous <i>C. maxima</i> seed extracts in castor oil induced diarrheal rats. The <i>n</i>-hexane extract mainly contains oils while the aqueous extract was thick, brown solid. The aqueous and <i>n</i>-hexane seed extract of <i>C. maxima</i> expressed significant 2,2, diphenyl-1-picrythdrazyl (DPPH) scavenging activities at 6.25 – 1000 mg/mL with IC<sub>50</sub> values of 104.01 mg/mL, 29.27 mg/mL and 26.78 mg/mL for <i>n</i>-hexane, aqueous and vitamin C respectively. The hydroxyl radical scavenging activities of the <i>n</i>-hexane and aqueous seed extract of <i>C. maxima</i> were significantly lower at higher concentrations compared with that of vitamin C. Furthermore, the total antioxidant capacities of <i>n</i>-hexane (22.08mg/mL) and aqueous seed extract (11.03 mg/mL) of <i>C. maxima</i> were found to be higher than that of vitamin C (134.46 mg/mL). The aqueous extracts (658.33±380.08 mg QE/g) total tannins were not significantly different from the <i>n</i>-hexane extract (468.33±102.55 mg QE/g) while the <i>n</i>-hexane extract contains significantly higher total phenolics (2.93±1.25 mg GAE/g) compared with the aqueous extract (0.19±0.04 mg GAE/g). Percentage inhibition of stooling was found to be 57±22%, 41±16%, and 46±11% for loperamide, <i>n</i>-hexane, and aqueous respectively. The study concludes that aqueous and n-hexane seed extracts of <i>C. maxima</i> (pumpkin) possess in vitro antioxidant activities and antidiarrheal properties.

scholarly journals Antioxidant and antimicrobial activities against Enterobacter cloacae of extracts of Eclipta alba Hassk.

2016 ◽  
Vol 19 (4) ◽  
pp. 76-83
Author(s):  
Trang Thi Xuan Dai ◽  
Anh Thi Tu Vo
Keyword(s):  
Free Radical ◽  
Vitamin C ◽  
Ethyl Acetate ◽  
Ethyl Acetate Extract ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Enterobacter Cloacae ◽  
Free Radical Scavenging ◽  
Antioxidant Vitamin ◽  
Eclipta Alba

This study was subjected to investigate antimicrobial and antioxidant properties of Eclipta alba extracts (methanol, hexane, chloroform and ethyl acetate extracts). The antioxidant property of the extract was assessed by 2,2- diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. Kirby-Bauer method was used to determine the antibacterial activity against Enterobacter cloacae of the extracts. The extracts of Eclipta alba were tested against E. cloacae. The highest antibacterial potentiality was exhibited by the ethyl acetate extract of E. alba leaves, means of zones of bacterial growth inhibition are 26.3 mm at a concentration of 32 μg/mL. DPPH free radical scavenging effect of the extracts was compared with standard antioxidant vitamin C. The highest antioxidant activity was exhibited by the ethyl acetate extract of E. alba leaves. The result also showed that the DPPH scavenging activity of ethyl acetate extract from leaves of E. alba was high (EC50 = 419.38 μg/mL). However, this result was 18.99 times lower than that of vitamin C (EC50 = 22.08 μg/mL).

scholarly journals Synergistic effect of fasting-mimicking diet and vitamin C against KRAS mutated cancers

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Maira Di Tano ◽  
Franca Raucci ◽  
Claudio Vernieri ◽  
Irene Caffa ◽  
Roberta Buono ◽  
...  
Keyword(s):  
Vitamin C ◽  
Synergistic Effect

scholarly journals Antioxidant capacity, phenolic and vitamin C contents of quinoa (Chenopodium quinoa Willd.) as affected by sprouting and storage conditions

2017 ◽  
Vol 12 (1) ◽  
Author(s):  
Maura N. Laus ◽  
Mariagrazia P. Cataldi ◽  
Carlo Robbe ◽  
Tiziana D'Ambrosio ◽  
Maria L. Amodio ◽  
...  
Keyword(s):  
Vitamin C ◽  
Antioxidant Capacity ◽  
Peroxyl Radical ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Chenopodium Quinoa ◽  
Storage Conditions ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Reducing Activity

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.

scholarly journals Partition Behavior in Aqueous Two-Phase System and Antioxidant Activity of Flavonoids from Ginkgo biloba

2018 ◽  
Vol 8 (11) ◽  
pp. 2058 ◽  
Author(s):  
Can Liu ◽  
Shuochen Liu ◽  
Lingli Zhang ◽  
Xiaoxue Wang ◽  
Lanqing Ma
Keyword(s):  
Antioxidant Activity ◽  
Polyethylene Glycol ◽  
Free Radical ◽  
Vitamin C ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Phase System ◽  
Two Phase ◽  
Extraction Parameters ◽  
Partition Behavior

In this work, the aqueous two-phase extraction parameters and in vitro antioxidant activity of total flavonoids from Ginkgo biloba were investigated. The partition behavior of the flavonoids in an aqueous two-phase system (ATPS) was analyzed, the extraction parameters were optimized using response surface methodology, and the antioxidant activity of the flavonoids was determined by free-radical scavenging tests (1,1-diphenyl-2-picrylhydrazyl (DPPH) assay) and the ferric reducing/antioxidant power (FRAP) assay. The results showed that the concentration of ammonium sulfate was negatively correlated with the phase-volume ratio, whereas the concentration of polyethylene glycol was positively correlated. The maximum yield of flavonoids (4.11 mg g−1) was obtained under the following optimal extraction conditions: Concentration of polyethylene glycol (PEG)1500 30% and (NH4)2SO4 22% (mass fraction), and liquid/solid ratio 40:1 (mL g−1). The antioxidant activity tests showed that the flavonoids from the G. biloba leaf exhibited free-radical scavenging activity, with an IC50 of 2.66 mg L−1, which was superior to that of vitamin C. The free-radical scavenging ability of the flavonoids was proportional to the flavonoid concentration. The total reducing power of the Ginkgo flavonoids was slightly lower than that of vitamin C. In this study, the distribution of flavonoids in an ATPS was analyzed and a mathematical model for the ATPS extraction of Ginkgo flavonoids was established, which provides a reference for further development and utilization of G. biloba.

Sign in / Sign up

Export Citation Format

Share Document