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Content of Phenolic Compounds and Antioxidant Capacity in Fruits of Apricot Genotypes  [PDF]
Jiri Sochor,Ondrej Zitka,Helena Skutkova,Dusan Pavlik,Petr Babula,Boris Krska,Ales Horna,Vojtech Adam,Ivo Provaznik,Rene Kizek
Molecules , 2010, DOI: 10.3390/molecules15096285
Abstract: Research on natural compounds is increasingly focused on their effects on human health. In this study, we were interested in the evaluation of nutritional value expressed as content of total phenolic compounds and antioxidant capacity of new apricot (Prunus armeniaca L.) genotypes resistant against Plum pox virus (PPV) cultivated on Department of Fruit Growing of Mendel University in Brno. Fruits of twenty one apricot genotypes were collected at the onset of consumption ripeness. Antioxidant capacities of the genotypes were determined spectrometrically using DPPH? (1,1-diphenyl-2-picryl-hydrazyl free radicals) scavenging test, TEAC (Trolox Equivalent Antioxidant Capacity), and FRAP (Ferric Reducing Antioxidant Power)methods. The highest antioxidant capacities were determined in the genotypes LE-3228 and LE-2527, the lowest ones in the LE-985 and LE-994 genotypes. Moreover, close correlation (r = 0.964) was determined between the TEAC and DPPH assays. Based on the antioxidant capacity and total polyphenols content, a clump analysis dendrogram of the monitored apricot genotypes was constructed. In addition, we optimized high performance liquid chromatography coupled with tandem electrochemical and spectrometric detection and determined phenolic profile consisting of the following fifteen phenolic compounds: gallic acid, 4-aminobenzoic acid, chlorogenic acid, ferulic acid, caffeic acid, procatechin, salicylic acid, p-coumaric acid, the flavonols quercetin and quercitrin, the flavonol glycoside rutin, resveratrol, vanillin, and the isomers epicatechin, (–)- and (+)- catechin.
Antioxidant Capacities and Total Phenolic Contents of 56 Wild Fruits from South China  [PDF]
Li Fu,Bo-Tao Xu,Xiang-Rong Xu,Xin-Sheng Qin,Ren-You Gan,Hua-Bin Li
Molecules , 2010, DOI: 10.3390/molecules15128602
Abstract: In order to identify wild fruits possessing high nutraceutical potential, the antioxidant activities of 56 wild fruits from South China were systematically evaluated. The fat-soluble components were extracted with tetrahydrofuran, and the water-soluble ones were extracted with a 50:3.7:46.3 (v/v) methanol-acetic acid-water mixture. The antioxidant capacities of the extracts were evaluated using the ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) assays, and their total phenolic contents were measured by the Folin-Ciocalteu method. Most of these wild fruits were analyzed for the first time for their antioxidant activities. Generally, these fruits had high antioxidant capacities and total phenolic contents. A significant correlation between the FRAP value and the TEAC value suggested that antioxidant components in these wild fruits were capable of reducing oxidants and scavenging free radicals. A high correlation between antioxidant capacity and total phenolic content indicated that phenolic compounds could be the main contributors to the measured antioxidant activity. The results showed that fruits of Eucalyptus robusta, Eurya nitida, Melastoma sanguineum, Melaleuca leucadendron, Lagerstroemia indica, Caryota mitis, Lagerstroemia speciosa and Gordonia axillaris possessed the highest antioxidant capacities and total phenolic contents among those tested, and could be potential rich sources of natural antioxidants and functional foods. The results obtained are very helpful for the full utilization of these wild fruits.
Phenolic Contents and Antioxidant Potential of Crataegus Fruits Grown in Tunisia as Determined by DPPH, FRAP, and β-Carotene/Linoleic Acid Assay  [PDF]
Farouk Mraihi,Mohamed Journi,Jamila Kalthoum Chérif,Munevver Sokmen,Atalay Sokmen,Malika Trabelsi-Ayadi
Journal of Chemistry , 2013, DOI: 10.1155/2013/378264
Abstract: Crataegus fruit is one of most important fruits in Tunisian flora. Some fruits of this genus are edible. This study was undertaken in order to examine the benefits of these fruits in human health and their composition of antioxidants including total polyphenol, flavonoids, proanthocyanidins content, and total anthocyanins. The antioxidative properties of the ultrasonic methanolic extract were assessed by different in vitro methods such as the FRAP, DPPH, and β-carotene/linoleic acid assay. We concluded that peel fraction of red fruits possessed relatively high antioxidant activity and might be a rich source of natural antioxidants in comparison with the pulp and seed fruit extract. The results also showed that hawthorn yellow fruit presents lower amounts of phenolic content, absence of anthocyanins, and less antioxidant capacity. Most of peel and seed fractions were stronger than the pulp fractions in antioxidant activity based on their DPPH IC50, FRAP values, and results of β-carotene/linoleic acid. The total phenolic compounds contents were also highly correlated with the DPPH method and the FRAP assay. 1. Introduction Dietary phenolic compounds have received much attention during the recent years due to their antioxidant and other biological properties imparting possible benefits to human health [1, 2]. Crude extracts of fruits, herbs, and vegetables are rich sources of polyphenols. These compounds include phenolic acids (hydroxybenzoic acids and hydroxycinnamic acids), flavonoids (flavonols, flavones, flavanols, flavanones, isoflavones, anthocyanins, and proanthocyanidins), vitamins, and carotenoids. These bioactive molecules can delay or inhibit the oxidation of lipids and other molecules by inhibiting the initiation or propagation of oxidative chain reactions [3]. Antioxidant activity of phenolic compounds is mainly due to their redox properties, which can play an important role in absorbing and neutralizing free radicals [4]. In order to receive a reliable picture of antioxidants content in Crataegus monogyna and Crataegus azarolus fruits extract, total polyphenols, total flavonoids, proantnocyanidins content, and total anthocyanins content were determined quantitatively using spectrophotometer methods. It was also shown that the measure of antioxidant capacity in natural products by only one assay is often not reliable; therefore, in this investigation, we used three complementary assays such as DPPH radical scavenging assay, ferric-reducing/antioxidant power (FRAP) and -carotene linoleic acid assay to check the antioxidant activity of these
Proximate Composition, Phenolic Content and Antioxidant Activities of Three Black Plum (Vitex sp.) Fruits: Preliminary Results
Charles O. Ochieng,Brian O. Nandwa
Journal of Food Technology , 2013, DOI: 10.3923/jftech.2010.118.125
Abstract: Highly reactive molecules (NO, O2 , HOO ) generated in biological systems are associated with initiation of degerative diseases. The antioxidants can reduce this risk. Fruits are one of the most important sources of antioxidants such as vitamins and phenolic phytochemicals. Vitex plants are wild tropical plant which has found wide application in traditional medicine and human food in the west and central African regions. This study was conducted to test antioxidant capacity, to compare the values of total phenolic and flavonoid contents and to estimate the proximate composition of three different fruits of Vitex species. The free radicals deactivating ability was measured using DPPH, NO scavenging assays and the reducing power tested by FRAP assay. Total phenolic content and flavonoid content were evaluated according to the Folin-Ciocalteu procedure and a colorimetric method, respectively. Vitex doniana and Vitex kiniensis extract showed high total phenol (601.40 and 719.83 mg GA/100 g FW, respectively) and flavonoid (2.35 and 2.09 μg RT/g extract) content and better reducing power by FRAP at 545.71 and 402.43 μMFe2+/100 g FW, respectively. The proximate compositions of the three fruits showed slight variation. The extracts demonstrated good scavenging activities against DPPH and NO assays which were not significantly different at (p<0.05). Thus these results suggest that extract three Vitex species may serve as potential source of natural antioxidant for food and nutraceautical application.
An in vitro analysis of the total phenolic content, antioxidant power, physical, physicochemical, and chemical composition of Terminalia Catappa Linn fruits
Marques, Marcelo Rodrigues;Paz, Diego Damasceno;Batista, Lívia Patrícia Rodrigues;Barbosa, Celma de Oliveira;Araújo, Marcos Ant?nio Mota;Moreira-Araújo, Regilda Saraiva dos Reis;
Ciência e Tecnologia de Alimentos , 2012, DOI: 10.1590/S0101-20612012005000023
Abstract: this study assessed the antioxidant, total phenolic, and physicochemical properties of in vitro terminalia catappa linn (locally called castanhola) using the dpph assay. the castanhola fruits had an average weight of 19.60 ± 0.00 g, combining shell, pulp, and seed weight, and a soluble solids content of 8 °brix. the chemical composition was determined with predominance of carbohydrates (76,88 ± 0,58%).the titration method was used to determine vitamin c content using 2,6-dichlorophenolindophenol (dcfi), known as reactive tillmans resulting in no significant levels. aqueous extracts of castanhola pulp showed a higher concentration of phenolics, 244.33 ± 18.86 gae.g-1 of fruit, and alcoholic extracts, 142.84 ± 2.09 gae.g-1 of fruit. ec50 values of the aqueous extract showed a greater ability to scavenge free radicals than the alcoholic extracts. the fruit had a significant content of phenolic compounds and high antioxidant capacity.
Phenolic profile and antioxidant activity of olive fruits of the Turkish variety “Sar ulak” from different locations
Arslan, D.,?zcan, M. M.
Grasas y Aceites , 2011, DOI: 10.3989/gya.034311
Abstract: The phenolic compounds, radical scavenging effect and antioxidant capacity of olive fruits from the “Sar ulak” variety were studied from four different locations: Alanya, Ceyhan, Silifke and Karaman in the Mediterranean region of Turkey. They were collected on three different harvest dates (HDs) and in two consecutive crop years. The levels of most of the phenolic compounds in the fruits of the Alanya location were remarkably high among the values (mg/kg) obtained for all location samples mainly on the first HDs, for instance hydroxytyrosol rose to 3596.4, luteolin rose to 269.5, vanillic acid rose to 159.8 and caffeic acid rose to 62.1. The olive fruits from Alanya, which had the highest average rainfall compared to the other locations, showed the highest phenolic content. The olive fruits from Silifke, which had a dramatic decrease in rainfall between the two crop years, showed a reduction in total phenolic content in the following crop year. The highest oleuropein contents (mg/kg) were detected for the fruit samples grown in Silifke (963.5-2981.8) and for Karaman (835.2-655.6). All of the locations showed similar changes in antioxidant activity pointing to an increase with later HDs. The effect of HD on the phenolic compounds such as 4-hydroxyphenyl acetic acid, caffeic acid, syringic acid and hidroxytyrosol, luteolin, chlorogenic acid and 3,4-dihydroxybenzoic acid were more dependent on the location factor. Se han estudiado los compuestos fenólicos, el efecto captador de radicales y la capacidad antioxidante de aceitunas de la variedad “Sar ulak” procedentes de cuatro localidades diferentes, Alanya, Ceyhan, Silifke y Karaman de la región mediterránea de Turquía, que fueron recogidas en tres diferentes fechas de cosecha (HDs) y en dos a os consecutivos de cultivos. Los niveles de la mayoría de estos compuestos fenólicos, expresados en mg/kg , de los frutos procedentes de Alanya fueron los mas altos entre los valores obtenidos de todos los lugares, principalmente en primer HDs, por ejemplo, el hidroxitirosol llega a 3596,4, la luteolina a 269,5, el ácido vanílico a 159,8 y el ácido cafeico a 62,1. Las aceitunas de Alanya, que tenían el mayor promedio de lluvias de las otras localidades, presentó el mayor contenido de fenoles. Las aceitunas de Silifke, que tuvo una dramática disminución de las precipitaciones entre dos a os de cultivo, mostraron una reducción en el contenido de fenoles totales en la campa a agrícola siguiente. Los contenidos más alto de oleuropeína fueron detectados en las muestras de frutos cultivadas en Silifke (963,5 a 2.981,8 mg/kg
EVALUATION OF ANTIOXIDANT ACTIVITY OF FLAVONOID AND PHENOLIC CONTENTS OF LUFFA ECHINATA ROXB. FRUITS AND NYCTANTHUS ARBOR-TRISTIS LEAVES  [cached]
Anuj Modi,Vimal Kumar,Prateek Jain,Sunil Jain
International Journal of Phytopharmacy , 2011, DOI: 10.7439/ijpp.v1i1.158
Abstract: Objective: To obtain a systematic record of the relative antioxidant activity of flavonoid and phenolic contents of Luffa echinata Roxb fruit and Nyctanthus arbor-tristis leaves extracts. Methods: Phenolic and flavonoid content were determined by using gallic acid and quercetin as standard, antioxidant properties were evaluated by the methods, namely the Trolox equivalent antioxidant capacity assay (TEAC), Oxygen radical absorbance capacity (ORAC) Assay and DPPH free radical scavenging activity assay. Results: Total phenolic content were found 76.34 ±0.44 and 45.53 ±0.65 mg/g, while flavonoid contents were found 65.98 ±0.83 and 34.92 ±0.76 mg/g in Luffa echinata Roxb and Nyctanthus arbor-tristis respectively. In the Trolox equivalent antioxidant capacity assay, TEAC value were found 0.34 mmole/g and 0.28 mmole/g, while in Oxygen radical absorbance capacity assay, ORAC value was found 253.7m moles TE #/ g and 221.6 m moles TE #/ g, where as DPPH free radical scavenging activity assay showed IC50 value 188 ±0.87 and 176 ±0.68 for Luffa echinata Roxb and Nyctanthus arbor-tristis extracts. Conclusion: The present studies suggest that both the plants have moderate to potent antioxidant activity.
Characterisation of Phenolic Compounds in South African Plum Fruits (Prunus salicina Lindl.) using HPLC Coupled with Diode-Array, Fluorescence, Mass Spectrometry and On-Line Antioxidant Detection  [PDF]
Alet Venter,Elizabeth Joubert,Dalene de Beer
Molecules , 2013, DOI: 10.3390/molecules18055072
Abstract: Phenolic compounds are abundant secondary metabolites in plums, with potential health benefits believed to be due to their antioxidant activity, amongst others. Phenolic characterisation of South African Prunus salicina Lindl. plums is necessary to fully evaluate their potential health benefits. An HPLC method using diode-array detection (DAD) for quantification of phenolic compounds was improved and fluorescence detection (FLD) was added for quantification of flavan-3-ols. Validation of the HPLC-DAD-FLD method showed its suitability for quantification of 18 phenolic compounds, including flavan-3-ols using FLD, and phenolic acids, anthocyanins and flavonols using DAD. The method was suitable for characterisation of the phenolic composition of 11 South African plum cultivars and selections, including various types with yellow and red skin and flesh. The method was used in conjunction with mass spectrometry (MS) to identify 24 phenolic compounds. Neochlorogenic acid and cyanidin-3- O-glucoside were the major compounds in most of the plums, while cyanidin-3- O-glucoside was absent in Sun Breeze plums with yellow skin and flesh. Post-column on-line coupling of the ABTS ?+ scavenging assay with HPLC-DAD enabled qualitative evaluation of the relative contribution of individual phenolic compounds to the antioxidant activity. The flavan-3-ols, neochlorogenic acid and cyanidin-3- O-glucoside displayed the largest antioxidant response peaks.
Phenolic Contents and Antioxidant Activity of Various Date Palm (Phoenix dactylifera L.) Fruits from Saudi Arabia  [PDF]
Ebtesam Abdullah Saleh, Manal Said Tawfik, Hamza Mohammed Abu-Tarboush
Food and Nutrition Sciences (FNS) , 2011, DOI: 10.4236/fns.2011.210152
Abstract: The present study aimed to estimate the individual and total phenols and antioxidant activity of the aqueous and alcoholic extracts of three premium quality date varieties (Khalas, Sukkari and Ajwa) from Saudi Arabia. In general, water extract has shown significantly higher contents of total phenols than alcoholic, especially in Ajwa (455.88 and 245.66 mg/100 g respectively). However, phenolic profile indicated that Sukkari contained the highest rutin concentration (8.10 mg/kg), whereas, catechin was approximately the same in Sukkari and Ajwa (7.50 and 7.30 mg/kg respectively). Khalas was the highest variety content of caffeic acid (7.40 mg/kg). A significant difference has indicated among extracts and varieties in suppressing lipid peroxidation. Sukkari and Ajwa have reduced the oxidation with 50% at lower concentration in water extract than alcoholic (0.63, 0.70 and 1.60, 1.43 mg/ml respectively). Furthermore, high positive linear correlation was found between total phenols in water (r = 0.96) and alcohol (r = 0.85) extracts and inhibition of lipid oxidation activity. The compounds responsible for the activity were catechin (r = 0.96), and rutin (r = 0.74) in water extract, whereas this correlation decreased in alcoholic extract (r = 0.66) for catechin and very weak (r = 0.38) for rutin. No correlation was found between caffeic acid and lipid peroxidation in both extracts. Similar significant results were obtained with DPPH test, except with Sukari, which has shown no difference between aqueous and alcoholic extracts (4.30, 4.10 mg/ml respectively).
Physicochemical characterization and antioxidant capacity of pitanga fruits (Eugenia uniflora L.)
Bagetti, Milena;Facco, Elizete Maria Pesamosca;Piccolo, Jaqueline;Hirsch, Gabriela Elisa;Rodriguez-Amaya, Delia;Kobori, Cintia Nanci;Vizzotto, Márcia;Emanuelli, Tatiana;
Ciência e Tecnologia de Alimentos , 2011, DOI: 10.1590/S0101-20612011000100021
Abstract: this study was carried out to obtain more information about the physicochemical properties, composition, and antioxidant activity of pitanga fruits (eugenia uniflora l.), particularly fruits from the state of rio grande do sul, brazil. pitanga with different flesh colors (purple, red, and orange) from tree selections cultivated at embrapa clima temperado (rs-brazil) were analyzed. only slight differences were observed in the quality parameters and in the proximate and fatty acid compositions among the fruits studied. the extracts from purple-fleshed pitanga had the highest total phenolic and anthocyanin contents along with the highest antioxidant capacity. the antioxidant capacity (dpph and frap assays) of methanolic pitanga extracts was highly correlated with the total phenolic content, but in ethanolic extracts, the anthocyanin content was correlated only with the frap antioxidant capacity. orange fleshed pitanga had higher β-cryptoxanthin and β-carotene levels than those of the red fruit, which had higher lycopene content. the results indicate that the purple-fleshed pitanga, cultivated in rio grande do sul, is a rich source of phenolic compounds and has high antioxidant capacity. the red and orange-fleshed pitanga, on the other hand, are rich sources of carotenoids.
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