Effect of solvents in extracting polyphenols and antioxidants of selected raw vegetables

Thirty-seven raw vegetables were extracted using four solvent systems: 70% acetone, 70% ethanol, 70% methanol, and distilled water. The extracts were tested for their total phenolic content, total flavonoid content and antioxidant activities (using diphenylpicryl-hydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays). The results revealed the effect of different extracting solvents in altering the quantitative analyses of all vegetables and 70% acetone was identified as the most efficient solvent for extracting polyphenolic antioxidants from the vegetables. The highest total phenolic content and total flavonoid content were obtained from 70% acetone extract of Portulaca oleracea (138.2 ± 2.1 mg GAE/g dw basis) and 70% methanol extract of Cosmos caudatus (27.7 ± 1.0 mg QE/g dw basis), respectively. The 70% acetone extract of Etlingera elatior with moderate amount of total phenolic content exhibited the highest antioxidant activity in both assays. The correlation analyses within 37 different extracts of each solvent extraction demonstrated weak to moderate relationships between all the studied parameters. The highest r value of 0.7139 (p < 0.001) was determined between total phenolic contents and FRAP values of the 70% methanol extracts. Meanwhile, a wide range of correlation coefficients was derived from correlation analyses within four different extracts of each vegetable, with the highest relationship between total phenolic contents and FRAP values for the extracts of Coriandrum sativum (r = 0.9998, p < 0.001).     

Survey of antioxidant capacity and nutritional quality of selected edible and medicinal fruit plants in Hong Kong

Twenty-two samples (including fruits, pulp, peel, or seeds) from 13 edible and medicinal fruit plant species selected in Hong Kong were investigated for their antioxidant capacity, nutritional quality and phenolic profiles. Significant variation existed among the tested samples in all the antioxidant and nutritional parameters. Proanthocyanidins, flavonoids and phenolic acids were identified as major categories of phenolic compounds in these samples. Whole fruits of Hong Kong gordonia exhibited the strongest antioxidant capacity (213.4 mmol trolox/100 g DW) and had the second highest content of carotenoids. Seeds of Annona squamosa possessed the highest contents of total protein, fat and amino acids (17.6, 37.2 and 14.4%, respectively). Most peel and some seeds contained high levels of phenolics, carotenoids and vitamin C, which contributed to their strong antioxidant activity. Some of the fruits, peel or seeds from these Hong Kong plants can be a potential resource of functional components and nutraceuticals.     

Phenolic compounds and antioxidant activity of Spanish commercial grape juices

Evaluation of the antioxidant activity of components of the diet is important in order to establish healthy consumption patterns. Data are reported here on the antioxidant activity (FRAP and ABTS), of 20 commercial grape juices and 10 typical Spanish wines and on their content of total phenolic compounds, anthocyanins, flavonoids and 10 individual phenolic compounds (flavanols, benzoic acids and cinnamic acids, measured by HPLC-UV). Red grape juices had a significantly higher (p < 0.05) concentration of total phenols (1177 vs. 744 mg gallic acid/L), flavonoids (98 vs. 63 mg catechin/L) and a higher antioxidant activity (9.16 vs. 2.83 meq Trolox/L) in comparison to white grape juices. In comparison to the white wines, white grape juices contained more total phenols (744 vs. 286 mg gallic acid/L) and flavonoids (63 vs. 29 mg catechin/L) and evidenced higher antioxidant activity (p < 0.05). In comparison to the red wines, a lower content of total phenols (286 vs. 2358 mg gallic acid/L) and flavonoids (228 vs. 29 mg catechin/L) and an absence of anthocyanins were observed in the white wines, which are therefore less antioxidant. Although a two-fold higher concentration of antioxidant compounds was found in red wines than in red grape juices, the latter may be a good option for all age groups because of the absence of alcohol and the potentially beneficial health effects of their phenolic composition and elevated antioxidant activity.     

Cold storage of blueberry (Vaccinium spp.) fruits and juice: Anthocyanin stability and antioxidant activity

Blueberries (Vaccinium spp.) may be considered one of the best potential sources of antioxidants in the diet. This characteristic results from the presence of flavonoids (especially anthocyanins), tannins and phenolic acids in the fruits. The objective of this work was to analyze the anthocyanin stability and antioxidant activity of refrigerated whole blueberry juice stored at 4 °C for 10 d, and of fruits stored frozen (−18 °C) for 6 months, in order to determine the changes occurring during storage. The frozen fruits showed a significant increase (p < 0.05) in antioxidant activity during the 3rd month of frozen storage, followed by a decrease up to the end of the 6-month period. The juice was analyzed every other day, and the antioxidant activity changed on the 8th d of refrigerated storage, remaining stable up to the 10th d. There were significant losses of anthocyanins both in the frozen fruits (59%) and refrigerated juice (83%). The antioxidant capacity was shown to be stable during cold storage both in the case of the fruits and whole juice, whereas the anthocyanins were degraded, possibly due to oxidations and/or condensation reactions with other phenolic compounds. More studies are required to optimize the storage time and temperature of these products with respect to nutrient stability.     

Antioxidant capacity of underutilized Malaysian Canarium odontophyllum (dabai) Miq. fruit

This study aimed to evaluate the antioxidant capacities of various parts of the dabai (Canarium odontophyllum Miq.) fruit. The antioxidant capacities of C. odontophyllum were evaluated using a β-carotene bleaching assay, ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assays. Total phenolic content of the dabai fruit was estimated using the Folin–Ciocalteu method. The antioxidant capacities ranked in the following order: skin > flesh + skin > flesh > kernel. Our findings show that a high correlation exists between total phenolic content and total antioxidant activity. This indicates that phenolic compounds could be the major contributors to the antioxidant capacity of C. odontophyllum fruit. Therefore, dabai fruit, especially the skin, can be recommended as a major source of natural antioxidants.     

Evaluation of antioxidant activities of phenolic compounds from two extra virgin olive oils

The aim of this work was to investigate the antioxidant properties of two varieties of olive oil (Chétoui and Chemlali), and to study the protective effect of phenolic extract (PE) from these varieties against low density lipoprotein (LDL) oxidation in vitro. Antioxidant activities were examined as well, using different radical scavenging assays: radical scavenging activity by DPPH, and total antioxidant status by ABTS. The antioxidant effect of the oils on human LDL was evaluated by measuring levels of conjugated dienes and polyunsaturated fatty acids. Chemlali oil was less rich in total phenols (158 mg/kg) than Chétoui oil (395 mg/kg) (p < 0.05). The highest antioxidant activity was attributed to Chétoui oil (78.56% vs. 37.23% of DPPH and 2.42 vs. 0.61 mmol Trolox/kg; p < 0.05). Chétoui PE had a significantly greater inhibitory effect on LDL oxidation than Chemlali PE (lag time = 116 ± 6.05 min vs. 64 ± 11.31 min at 0.3 mg/l of PE respectively; p < 0.05). The differences in quantity and quality of the studied oils influenced their biological activities and they could provide beneficial effects in cardiovascular disease by inhibiting LDL oxidation.     

Total phenolic compounds and antioxidant potential of Hedychium spicatum Buch. Ham. ex D. Don in west Himalaya,India

Total phenolic compounds and antioxidant potential of Hedychium spicatum were analyzed for 16 different natural populations located in Uttarakhand (west Himalaya) for promotion as health or medicinal food. Total phenolic compounds varied among populations from 4.70 mg gallic acid equivalent (GAE) to 2.84 mg GAE/g dry weight. Three in vitro antioxidant assays, i.e. azinobisethylbenzothiazoline-6-sulphonic acid radical scavenging (ABTS) assay, diphenyl-2-picrylhydrazyl (DPPH) assay and ferric reducing antioxidant power (FRAP) assay, showed significant (p < 0.05) differences across populations. ABTS assay showed highest values of antioxidant potential ranging from 2.581 mM ascorbic acid equivalent (AAE) per 100 g to 1.91 mM AAE per 100 g dry weight, followed by FRAP assay (1.921–0.6635 mM AAE per 100 g). Lowest values were observed for DPPH assay, which varied from 0.549 to 1.059 mM AAE per 100 g dry weight. All assays (ABTS, DPPH and FRAP) showed significant (p < 0.05) correlation with total phenolic compounds. Total phenolic compounds showed a significant relationship (p < 0.05) to altitude.     

Phenolic,alpha-tocopherol,beta-carotene and fatty acid composition of four promising jujube (Ziziphus jujuba Miller) selections

The phenolic, alpha-tocopherol, beta-carotene and fatty acid composition of four jujube selections were investigated in this study. Phenolic compounds, alpha-tocopherol and beta-carotene were analyzed with an HPLC device equipped with a diode array detector, and the fatty acid methyl esters were analyzed with QP 5050 GC/MS equipped with a CP-Wax 52 CB column. Among the jujube selections, considerable differences in phenolic and fatty acid contents were found. Catechin, caffeic acid, p-coumaric acid, ferulic acid, rutin, apigenin-7-glucoside, eriodictyol, quercetin, p-hydroxybenzoic acid, chlorogenic acid and syringic acid were isolated from leaves. Rutin content was very high in the leaves of all the jujube selections, ranging from 269.0 to 367.90 mg/100 g, followed by apigenin-7-glucoside (22.90–49.38 mg/100 g) and eriodictyol (5.06–6.27 mg/100 g). Seven phenolic compounds, catechin, caffeic acid, epicatechin, ferulic acid, rutin, p-hydroxybenzoic acid and chlorogenic acid, were isolated from fruits of jujube selections. Catechin level ranged from 2.46 to 3.74 mg/100 g, and rutin level ranged from 0.88 to 3.60 mg/100 g for fruits. Predominant phenolics were rutin and apigenin-7-glucoside for leaves, and catechin and rutin for fruits. Jujube leaves contained higher amounts of phenolic compounds than jujube fruits. Alpha-tocopherol was only detected in fruits of selections 20-Ç-22 and 20-Ç-52 (0.04 and 0.07 mg/100 g, respectively). Beta-carotene was significantly higher in 20-Ç-22 (35.0 μg/100 g) than in the other selections. Lipid content of the fresh fruits ranged from 0.06% to 0.10% among the four jujube selections. The predominant fatty acids in all jujube selections were oleic acid, linoleic acid, palmitic acid and palmitoleic acid. Unsaturated fatty acids comprised 68.54–72.44% of the total fat in jujube fruit.     

Changes of antioxidant activity and total phenolic compounds during storage of selected fruits

The antioxidant activity and total phenolic compounds in various fruits (common fruits—two varieties of mangoes (ripe and unripe), guava, papaya, mangosteen and banana; and two indigenous fruits—makiang and maluod) were investigated. Banana and papaya showed the lowest activity, and mangosteen, mango and guava exhibited high levels of antioxidant activity (oxygen radical absorbance capacity (ORAC), and ferric-reducing antioxidant power (FRAP)) as well as total phenolic compounds. The studied indigenous fruits (makiang and maluod) are high in both antioxidant activity (ORAC and FRAP) and total phenolic compounds. Three independent batches of selected fruits—guava (Psidium guajava), makiang (Cleistocalyx nervosum var paniala) and maluod (Elaeagnus iatifolia, Linn)—were used to determine the changes in antioxidant activity (AO) and total phenolic compounds (TP) during storage at −20 °C for 3 months and at 5 °C for 10 days. The ORAC-AO during storage at −20 °C for 2 wk decreased significantly in homogenised guava (23%) and in whole fruits of maluod (62%), whereas that of makiang was constant. A continuous decrease in TP was found in homogenised guava throughout the 3-months storage period (69% retention) whereas constant levels were found in other fruits. At 5 °C, a decrease in the ORAC-AO in the whole fruits of makiang (14%) and maloud (70%) was found after a 3-days storage, whereas a gradual increase in the activity (120–190%) was found in the whole fruit of guava throughout the storage period. Among the factors which can affect the levels of antioxidant activity and total phenolic compounds in fruits could be the species, size and texture of fruits, the prepared form of the samples and the conditions of storage (e.g. time, temperature). Preliminary studies on the effect of storage in individual types of fruits are suggested before making a sampling plan for systematic analyses of their antioxidant activity.     

Phenolic acids,flavonols and anthocyanins in Corema album (L.) D. Don berries

Phenolic compounds of Corema album (Ericaceae) wild edible berries were determined by LC–DAD–MS/MS. Fifteen compounds were identified and quantified, including phenolic acids (2268.1 ± 229.2 mg/kg of dried weight, DW) such as chlorogenic and neochlorogenic acids, flavonols (638.3 ± 80.1 mg/kg DW) including quercetin 3-O-hexoside and rutin, and the anthocyanins (19. 6 ± 2.4 mg/kg DW) cyanidin 3-O-glucoside, cyanidin 3-O-pentoside and delphinidin 3-O-hexoside. Phenolic acids, the main phenolic compounds in this fruit, were fractionated into their free and bound forms, and analysed by GC–MS after hydrolysis. Eleven compounds (benzoic, salicylic, t-cinnamic, p-hydroxybenzoic, vanillic, gentisic, syringic, p-coumaric, gallic, ferulic and caffeic acids) were identified on the basis of GC retention times and simultaneously recorded mass spectra, namely caffeic, benzoic, ferulic and vanillic acids as the major phenolic acids in Corema album berries.     

Antioxidant activity and phenolic content in three lupin species

Total phenolic compounds, phenolic acids and flavonoid contents and antioxidant activities were measured in extracts from seeds of Lupinus albus, Lupinus luteus and Lupinus angustifolius cultivars. The total phenolic compound contents varied from 491.51 to 731.14 mg/100 g d.m. for cvs. Butan (L. albus) and Parys (L. luteus), respectively. Protocatechuic acid was the most abundant in seeds of yellow lupin (up to 73.60 mg/kg d.m.), whereas p-hydroxybenzoic acid in narrow-leaf lupin (about 43 mg/kg d.m.). The HPLC (high performance liquid chromatography) analysis revealed two dominant flavonoid compounds, which were identified by HPLC/MSⁿ to be apigenin-6,8-di-C-β-glucopyranoside and apigenin 7-O-β-apiofuranosyl-6,8-di-C-β-glucopyranoside. The highest content of the apigenin glycosides was recorded in yellow lupin while the lowest in white lupin. A positive correlation between the content of the analyzed compounds and the antioxidant activity measured by 2,2′-diphenyl-1-picrylhydrazyl (DPPH) method was established, but no such relation was found using the radical-trapping antioxidant parameter (TRAP) method. Modification of the peroxyl radical-trapping potential of lupin extracts by formation of phenoxyl radicals is suggested.     

Minor components and oxidative stability of cold-pressed oil from rapeseed cultivars in China

The contents of the minor components and induction period (IP) of cold-pressed oils from 203 rapeseed varieties from the Yangtze River Valley in China were determined. The average contents of total phenolics, phytosterols, tocopherols, β-carotene, lutein and chlorophyll of the samples were 36 mg/100 g, 826 mg/100 g, 378 mg/kg, 2.4 mg/kg, 104 mg/kg and 8.2 mg/kg, respectively. There were significant differences (p < 0.0001) among the varieties in the content of these minor components. Correlation analysis revealed there was a positive correlation between the IP and content of total polyphenols (r = 0.303, p < 0.0001), lutein (r = 0.250, p < 0.0001) and total tocopherols (r = 0.225, p = 0.001). Additionally, the IP negatively correlated with total phytosterols and chlorophyll content. Principal component analysis differentiated the rapeseed oils based on their IP and total phenolic, tocopherol, β-carotene, lutein and chlorophyll content.     

Determination of free and bound phenolics using HPLC-DAD,antioxidant activity and in vitro digestibility of Eragrostis tef

White and brown Eragrostis tef were assessed for total flavonoid and phenolic content, HPLC profile of the most common phenolics and antioxidant activity including both free and bound phenolics. Antioxidant activity was evaluated in correlation with free and bound phenolics and in vitro digestibility was determined. Content of flavonoids (0.52–1.02 mg RE/g) and phenolics (0.90–1.42 mg GAE/g) as well as antioxidant activity (1.70–4.37 μmol TEAC/g using ABTS method) was higher in free phenolic fraction. Correlation showed that bound flavonoids were not significant contributors to antioxidant activity (R² = 0.4513 and 0.4893, respectively). The main free phenolics in brown teff were trans-p-coumaric, protocatechuic, ferulic and gallic acids, while the major free phenolics in white teff were rutin, protocatechuic and ferulic acids. The main bound phenolics in brown teff were ferulic and gallic acids, quercetin and catechin, in white teff ferulic acid, rutin, catechin and quercetin. Cooked teff showed very high level of in vitro organic matter digestibility (80.5–85.1%), whereas brown teff was significantly more digestible than white teff (P < 0.05).     

Antioxidant and flavor properties of Angelica sinensis extracts as affected by processing

Angelica sinensis (AS) was extracted with water or 20% ethanol for different time periods, and the antioxidant activity as well as flavor quality of the extracts were investigated. The AS extracts contained significant amount of phenolic acids, including nicotinic acid, phthalic acid, p-coumaric acid, and ferulic acid. Regardless the water or alcohol extraction, most of the phenolic acids reached their maximum values in 15 min. Assays including inhibition of 1,1-diphenylpicrylhydrazyl (DPPH), lipid peroxidation, and DNA relaxation activities also indicated that 15 min extraction resulted in a product with the highest antioxidant activity. The 15 min AS extracts in the concentration range of 20–200 μg/ml also showed inhibitory effects on NO production in LPS-activated RAW 264.7 macrophage in a dose-dependent manner. Statistical analysis revealed that the antioxidant activity and phenolic acid concentration for all AS extracts exhibited a positive and significant linear correlation, suggesting that the phenolic acids are the important contributors for the antioxidant activity of the AS extracts. The contents of volatile compounds of AS were much higher in the 20% ethanol extracts than those in water extracts. In the 20% ethanol extracts, the amount of ligustilide, butylidene phthalide and butyl phthalide were higher in the 30-min extracts than that prepared for longer time. Considering both of antioxidant activity and flavor quality, the AS extract should be prepared with 20% ethanol with extraction time less than 30 min.     

Profiling antioxidant activity of two primocane fruiting red raspberry cultivars (Autumn bliss and Polka)

Fruit extracts of two raspberry (Rubus idaeus L.) cultivars (Autumn Bliss and Polka) were analysed for total phenolic (TPC) and anthocyanin (TACY) content. Correlation of TPC with total antioxidant capacity (TAC) showed higher free-radical scavenging properties of Autumn Bliss (r² = 0.9999) compared to Polka (r² = 0.8972). Correlation coefficient between TACY and TAC were higher in Autumn Bliss (r² = 0.9939) compared to Polka fruits (r² = 0.8419). Although total protein concentrations were similar in both cultivars (∼0.35 mg mL⁻¹), activities of peroxidases and polyphenol oxidases were much higher in Polka, which were confirmed with isoelectric focusing in cationic (pI 9.3) and anionic (pI 3.6) range. HPLC detection showed that among detected flavonoids (catechin, epicatechin, epicatechin gallate, rutin, myricetin, resveratrol, quercetin and kaempferol) epicatechin appears to be the most abundant compound. Chlorogenic, caffeic and p-coumaric acid were also detected. The results indicate that the changes in enzymes activities related to content of substrates play an important role in nutrient quality definition of raspberry fruits.     

Polyphenols,methylxanthines, and antioxidant capacity of chocolates produced in Serbia

Different kinds of chocolates produced in Serbia were analyzed regarding total polyphenol, flavonoid and proanthocyanidin content using spectrophotometric methods. Flavan-3ols and methylxanthines in all samples were determined with RP-HPLC. DPPH, FRAP, ABTS and ORAC assays were applied for measuring antioxidant capacity. The average of all four antioxidant tests for each cocoa product was used for calculating antioxidant potency composite index (ACI). Obtained results for all four assays have shown that antioxidant capacity of analyzed chocolate/cocoa extracts followed cocoa, polyphenol, flavonoid, and proanthocyanidin contents. Although the addition of raspberries to dark chocolates had no significant influence on their total polyphenol, flavonoid and proanthocyanidin contents, statistical analysis showed that there was significant increase in the antioxidant capacity of dark chocolates with raspberry compared to plain dark chocolates (p = 0.007). Overall range for theobromine content varied from 5.5 to 22.3 mg/g depending on the product type, while the content of caffeine was 13–30 times lower in all analyzed cocoa products. In addition, correlation between antioxidant potency composite index and declared percentage of cocoa was high (R² = 0.798, p < 0.05) and indicated that declared cocoa content was a reliable indication for antioxidant capacity of chocolates produced in Serbia.     

Phenolic acids in potatoes,vegetables, and some of their products

The aim of this study was to determine the distribution and contents of soluble and total phenolic acids in a wide range of vegetables consumed in Finland. The determinations were performed from the pooled samples (14 potato and 45 other vegetable samples). Soluble phenolic acids were extracted with methanolic acetic acid and a tentative quantification was performed by HPLC. The contents of total phenolic acids were determined by HPLC after alkaline and acid hydrolyses. Chlorogenic acid derivatives were the most dominant soluble phenolic acids, while caffeic acid was the most dominant phenolic acid aglycone in the samples studied. Highest contents of soluble phenolic acids were found in raw and cooked potato peels: 23–45 mg/100 g fresh weight calculated as aglycones. In addition, pot-grown lettuces, Chinese cabbage, broccoli, carrot, aubergine, Jerusalem artichoke, peanut and most of the boiled and peeled potato tubers contained more than 5 mg/100 g of soluble phenolic acids calculated as aglycones. Among the best vegetable sources of total phenolic acids were potatoes, with contents varying from 7.9 mg/100 g (cooked and peeled Rosamunda variety) to 52 mg/100 g (cooked peel of Van Gogh variety), and red cabbage, carrot, aubergine, Jerusalem artichoke, broccoli, pot-grown lettuce, spinach, radish and red beet, with contents from 11 mg/100 g (spinach) to 52 mg/100 g (pot-grown lettuce Lollo Rosso). Variation in the phenolic acid contents of the vegetables was either moderate or considerable and needs further research.     

Phenolic and antioxidant composition of cider

Forty-four Asturian ciders were analysed for total phenolic content, phenolic profiles, and antioxidant capacity by the FRAP and the DPPH radical assays. The Folin index of ciders ranged between 446 and 1180 mg gallic acid/L. The phenolic profile of Asturian cider is mainly constituted by phenolic acids, flavan-3-ols, volatile phenols and dihydrochalcones. The methods to determine the antioxidant activity of ciders were optimised in terms of suitable reaction times, within-day and between-day repeatability. Thus, time courses of ciders in the DPPH and the FRAP assays were performed. Mean values for antioxidant activity of cider, expressed in ascorbic acid equivalents were 2.9 mM (as determined by the DPPH assay). When the FRAP assay was used, the antioxidant capacity of cider increased with the reaction time from 3.8 mM (4 min) to 5.4 mM (40 min). Multivariate approaches based on phenolic composition can be useful to predict the antioxidant capacity of cider. Folin index and flavanols and hydrocaffeic acid contents were the best predictors for antioxidant activity.     

Quantitative high-performance liquid chromatography photo-diode array (HPLC-PDA) analysis of benzophenones and biflavonoids in eight Garcinia species

Eight Garcinia species including seven edible fruits, Garcinia aristata, G. hombroniana, G. intermedia, G. livingstonei, the “superfruit” G. mangostana, G. spicata, and G. xanthochymus, and the wood of G. kola were analyzed using a validated high-performance liquid chromatography photo-diode array (HPLC-PDA) method. Three benzophenones, guttiferone A, guttiferone E, and xanthochymol, and four biflavonoids amentoflavone, fukugeside, fukugetin, and volkensiflavone were identified and quantified by HPLC-PDA with authentic standards to verify their identity. Garcinia intermedia (IC₅₀ = 60.1 ± 27.3 μg/mL) and G. mangostana (IC₅₀ = 64.3 ± 11.3 μg/mL) fruits demonstrated the highest antioxidant activity. The highest level of xanthochymol was found in G. spicata (70.50 ± 1.10 mg/g dry weight), while the highest quantity of guttiferone A was detected in G. intermedia (43.00 ± 0.30 mg/g dry weight), and thus was determined to be rich in total phenolic content.     

Antioxidant activity and phenolic composition of organic and conventional grapes and wines

The phenolic compounds and antioxidant activity from Monastrell variety grapes obtained by organic and conventional agriculture during the last month of ripening and the wines obtained from them were studied. Samples of grapes were collected from the last month of ripening to full maturity in each plot, and winemaking was carried out on the day of the final collection of grape samples, coinciding with the maturity of the grapes. The antioxidant activity a month before harvesting was higher in the organic grapes (5.7 ± 0.03 mM Trolox/g) than in the conventional ones (4.40 ± 0.05 mM Trolox/g), although these differences disappear in the moment of harvesting. Similarly the total amount of phenolic compounds a month before harvesting was higher in the organic grapes (974.2 ± 54.4 mg/kg) than in the conventional grapes (447.7 ± 27.8 mg/kg), although these differences disappear at the moment of harvesting. In wine, phenolic compounds and the antioxidant activity were slightly higher in organic wine than in conventional wine, although the differences were not significant.