Phenolic compounds,lycopene and antioxidant activity in commercial varieties of tomato (Lycopersicum esculentum)

Nine commercial varieties of tomato (Rambo, Senior, Ramillete, Liso, Pera, Canario, Durina, Daniella and Remate) produced in Spain were analysed for their lycopene content, content of phenolic compounds and antioxidant capacity. The phenolic compounds were characterised as flavonoids (quercetin, kaempferol and naringenin) and hydroxycinnamic acids (caffeic, chlorogenic, ferulic and p‐coumaric acids). Antioxidant activity was measured using the DPPH and ABTS assays. The concentrations of lycopene and the various phenolic compounds as well as the antioxidant activity were significantly influenced by the tomato variety. Quercetin, the most abundant flavonoid, was found in concentrations ranging between 7.19 and 43.59 mg kg^?1 fresh weight, while naringenin levels were lower than 12.55 mg kg^?1. The most abundant hydroxycinnamic acid was chlorogenic acid, with values ranging from 14 to 32 mg kg^?1 fresh weight, followed by caffeic acid, while p‐coumaric and ferulic acids showed similar concentrations lower than 5 mg kg^?1. The highest content of lycopene was found in Ramillete, Pera and Durina (>50 mg kg^?1 fresh weight), while the concentration in the other varieties was between 50 and 30 mg kg^?1, with the exception of Liso (less than 20 mg kg^?1). The antioxidant activity of tomato extracts varied with the tomato variety and the assay method used. Individual compounds found to be significantly related to antioxidant capacity were lycopene and ferulic and caffeic acids, but not quercetin and chlorogenic acid. © 2002 Society of Chemical Industry     

Bioactive components and antioxidant capacities of different miniature tomato cultivars grown by altered fertilizer applications

This study investigated the organic acid and phenolic compound levels, total phenolic (TP) and antioxidant capacity (TEAC) of three miniature tomato cultivars grown on a farmer’s field with three different fertilizer applications. Analysis of phenolic compound (protocatechuic, vanillic, gallic, chlorogenic, caffeic, syringic, p-coumaric and ferulic acid, rutin, quercetin, catechin and phloridzine) organic acid (citric, tartaric, malic, succinic and fumaric acid), TP and TEAC levels in fruit samples showed statistically significant (p?<?0.05) differences between tomato cultivars and fertilizer applications. Rutin and chlorogenic acid were the predominant phenolic compounds found in all three cultivars. The highest rutin value (50.48 mg kg^?1 FW) was found in the Black Zebra fertilized with DAP plus organic and biochemical fertilizers and the lowest (20.52 mg kg^?1 FW) in the Black Zebra fertilized with DAP only. The highest chlorogenic acid value (63.31 mg kg^?1 FW) was found in the sweet pea currant fertilized with DAP only and the lowest (21.06 mg kg^?1 FW) in the Black Zebra fertilized with DAP plus chemical fertilizer. Citric acid content was the dominant organic acid in all three cultivars, with the highest citric acid value (6439.50 mg kg^?1 FW) found in the Sweet Pea Currant cherry tomato fertilized with DAP plus organic and biochemical fertilizers and the lowest (2435.20 mg kg^?1 FW) in the Window Box Yellow fertilized with DAP plus chemical fertilizer. Total phenolic and antioxidant levels in the window box yellow were significantly lower as compared to the Black Zebra and sweet pea currant varieties for all three fertilizer applications.     

Flavonoid and chlorogenic acid profiles of English cider apples

The phenolics in 20 apple cultivars comprising 19 English cider apple varieties and one dessert apple variety were analysed by high‐performance liquid chromatography/tandem mass spectrometry. The cider varieties contained higher levels than the dessert apple and the peel was richer in phenolics than the flesh. The phenolic concentrations ranged between 230 and 4920 mg kg^?1 fresh weight in the flesh and between 546 and 6306 mg kg^?1 fresh weight in the peel. Fifteen compounds from five different phenolic groups, flavan‐3‐ols, flavonols, anthocyanins, hydroxycinnamates and dihydrochalcones, were detected. The major components in the flesh were 5‐O‐caffeoylquinic acid, procyanidin B2 and (?)‐epicatechin, while (?)‐epicatechin and quercetin glycosides predominated in the peel. Copyright © 2007 Society of Chemical Industry     

Bioactive compounds from flesh and by-product of fresh-cut watermelon cultivars

BACKGROUND: The fresh‐cut industry produces thousands of tons of waste in non‐edible portions that present an environmental and management problem. These by‐products could be reused, in particular, to obtain bioactive compounds. In this study, five different fresh‐cut watermelon cultivars were assessed for their flesh and by‐product bioactive contents. RESULTS: The amount of by‐product varied between 31.27 and 40.61% of initial fresh weight (f.w.) depending on the cultivar. Watermelon cultivars were poor sources of total antioxidant, and the content was similar between rind and flesh samples (46.96 vs 43.46 mg ascorbic acid equivalent antioxidant capacity kg^?1 f.w.). However, the rind had a moderate total phenolic content higher than that of the flesh (458 vs 389 mg chlorogenic acid equivalent kg^?1 f.w.) and a much higher content of the amino acid citrulline (3.34 vs 2.33 g kg^?1 f.w.), which has potential bioactive properties. CONCLUSION: Watermelon rind offers quantitative interest as a natural source of citrulline, particularly Fashion, a dark‐skinned, seedless cultivar. More research is required on the efficient extraction of citrulline from watermelon rind and its suitability as an additive to drinks, juices or others products to produce new functional food products with valid health claims. Copyright © 2010 Society of Chemical Industry     

不同品种梨果实酚类物质和抗氧化性能分析

以我国北方11 个主栽梨品种黄冠、绿宝石、雪梨、鸭梨、丰水、南水、圆黄、黄金、华山、五九香和早酥的果实为试材,分别测定了果皮、果心和果肉中可溶性酚的含量,并对酚类物质进行了高效液相色谱（highperformance liquid chromatography,HPLC）分析。通过分别测定果皮、果肉、果心的乙醇提取液对DPPH自由基和羟自由基的清除能力,对其所含酚类物质的抗氧化性能进行了评价。结果表明：1）梨果心酚类物质含量高于果皮,果肉最低;2）在果心和果皮中均检测出熊果苷、没食子酸、儿茶素、绿原酸、咖啡酸、表儿茶素、香豆酸和芦丁8 种酚类物质,而在果肉中检测出熊果苷、没食子酸、绿原酸、表儿茶素和芦丁5 种物质;3）熊果苷、绿原酸和表儿茶素都为果肉和果皮的主要酚类物质,果肉中绿原酸的含量高于熊果苷,果皮则反之,果心所含酚类物质以绿原酸和熊果苷为主,且绿原酸的含量高于熊果苷;4）果皮、果肉、果心不同部位的酚类物质的含量与1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除能力和羟自由基清除能力间均分别呈显著正相关关系,表明酚类物质与自由基清除能力的关系密切。     

The content of chlorogenic acids in tropical fruits

This work investigates the content of feruloylquinic (FQA), caffeoylquinic (CQA) and dicaffeoylquinic (diCQA) acids in the peel, pulp and seed of 22 tropical fruits from Brazil. 3‐CQA, 4,5‐diCQA and 4‐ and 5‐FQA were not detected in any of the fruits analysed. Relatively small amounts of 4‐CQA (4.0–48.7 mg kg^?1) were found in the peel and/or pulp of seven of the fruits; only the peel of Artocarpus heterophyllus was significantly (p < 0.05) richer in this acid (1000 mg kg^?1). The distribution of 3,4‐ and 3,5‐diCQA in different parts of the fruits was relatively poor, only reaching levels of up to 16.4 mg kg^?1. The peel of A heterophyllus also showed the highest amount of 5‐CQA (13 000 mg kg^?1), while the seed of most fruits generally contained a lower amount of this acid than the peel or pulp. On the basis of the 5‐CQA content found in the pulp, 15 of the fruits were classified as follows: very low concentration (4.4–15.8 mg kg^?1), low concentration (28.9–66.4 mg kg^?1), medium concentration (132 mg kg^?1), high concentration (473–474 mg kg^?1) or very high concentration (1730 mg kg^?1); however, no 5‐CQA was detected in the pulp of the other seven fruits. Thus 5‐CQA was the major chlorogenic acid present in most of the tropical fruits studied and was generally accompanied by small amounts of 4‐CQA and 3,4‐ and 3,5‐diCQA. © 2002 Society of Chemical Industry     

Characterisation of the phenolic and flavonoid fractions and antioxidant power of Italian honeys of different botanical origin

BACKGROUND: Twenty‐seven Italian honey samples of different floral origin were analysed for total phenolic and flavonoid contents by a spectrophotometric method and for antioxidant power and radical‐scavenging activity by the ferric‐reducing/antioxidant power (FRAP) and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) assays respectively. In addition, the phenolic and flavonoid profiles were analysed using high‐performance liquid chromatography with UV detection (HPLC‐UV). RESULTS: The results of this study showed that honey contains copious amounts of phenolics and flavonoids. HPLC‐UV analysis showed a similar qualitative polyphenolic profile for all honey samples analysed. The main difference among samples was in the contribution of individual analytes, which was affected by floral origin. Total phenolic and flavonoid contents varied from 60.50 to 276.04 mg gallic acid equivalent kg^?1 and from 41.88 to 211.68 mg quercetin equivalent kg^?1 respectively. The antioxidant capacity was high and differed widely among samples. The FRAP value varied from 1.265 to 4.396 mmol Fe²⁺ kg^?1, while the radical‐scavenging activity expressed as DPPH‐IC₅₀ varied from 7.08 to 64.09 mg mL^?1. Correlations between the parameters analysed were found to be statistically significant (P < 0.05). CONCLUSION: The present study shows that honey contains high levels of phenolics and flavonoids and that the distribution of these compounds is influenced by the honey's floral origin. Copyright © 2009 Society of Chemical Industry     

Antioxidant Activity and Determination of Phenolic Compounds from <Emphasis Type="Italic">Eugenia involucrata</Emphasis> DC. Fruits by UHPLC-MS/MS

Fruits have been the focus of several studies aimed at finding new antioxidant sources for protection against the damage caused by reactive species. In this study, the antioxidant activity and the presence of phenolic compounds in all parts (peel, pulp, and seeds) of Eugenia involucrata DC. fruits were evaluated. DPPH^·, ABTS^·+, and ORAC methods were used to determine the antioxidant activity, and an UHPLC-MS/MS method was developed for determining the phenolic compounds (gallic, chlorogenic, ferulic, p-coumaric and ellagic acids, quercetin, and myricetin). In the determination of both antioxidant activity and phenolic composition, the efficiency of solvents with different polarities—methanol/H₂O (80:20, v/v), ethanol/H₂O (80:20, v/v), methanol/acidified water with phosphoric acid pH 3.00 (80:20, v/v), and ethyl acetate—for the extraction of the phenolic compounds, was also evaluated. All parts of E. involucrata fruits showed antioxidant activity, in the range of 36.68 ± 1.44 to 873.87 ± 18.24 μmol TE g^?1, being the highest values found in the seeds and peel when more polar extraction solvents were used. Six, five, and three phenolic compounds were identified and quantified in the pulp, peel, and seeds, respectively, with the highest abundance as p-coumaric acid (14 ± 2 mg kg^?1) in the pulp, quercetin (47 ± 5 mg kg^?1) in the peel, and gallic acid (74 ± 4 mg kg^?1) in the seeds, also when more polar solvents were used. Although antioxidant activity methods suggested that the peel and seeds have more antioxidant potential, a wider variety of compounds were determined in the pulp.     

Evaluation of table olive by‐product as a source of natural antioxidants

The main by‐product from the table olive canning industry is the stone with some residual olive flesh. The purpose of this study was to evaluate the composition – phenolic compounds (hydroxytyrosol, tyrosol and oleuropein) and tocopherol – and the antioxidant activity in different fractions (flesh, stone and seed) from the table olive by‐product and the whole by‐product. The highest amounts of phenolic compounds (1710.0 ± 33.8 mg kg^?1) as well as the highest antioxidant activity (8226.9 ± 9.9 hydroxytyrosol equivalents mg kg^?1) were obtained in the seed. The highest amounts of hydroxytyrosol (854.8 ± 66.0 mg kg^?1) and tyrosol (423.6 ± 56.9 mg kg^?1) were found in the whole by‐product from the pepper stuffed olives, while the stone without seed had the maximum oleuropein content (750.2 ± 85.3 mg kg^?1). α‐Tocopherol values were between 79.8 ± 20.8 mg kg^?1 in the seed of the olive stone and 6.2 ± 1.2 mg kg^?1 in the whole by‐product from the anchovy‐stuffed olives. In light of the results obtained, it would seem possible to use table olive by‐product as a source of natural antioxidants in foods, cosmetics or pharmaceutical products, thus contributing to diminishing the environmental impact of table olive by‐product and to its revalorisation.     

Phenolic composition and antioxidant capacity of different heat-processed forms of sweetpotato cv. 'Beauregard'

Sweetpotato [ Ipomoea batatas (L.) Lam.] cv. 'Beauregard' roots were cooked using three different heat-processing techniques (baked in a conventional oven, baked in a microwave oven, and boiled). Total phenolic content, individual phenolic acids, and antioxidant capacity were determined using Folin-Denis assay, HPLC (high-performance liquid chromatography), and DPPH (1,1-diphenyl-2-picrylhydazyl) assay, respectively. The skin tissue (raw or processed) contained the highest concentration of total phenolics. All heat-processing methods resulted in a significant loss in total phenolic content and antioxidant capacity of the skin tissue. However, compared with the other processing methods, conventional oven baking resulted in greater losses in antioxidant capacity of skin tissue. Total phenolic content ranged from a low of 1.58 mg chlorogenic acid equivalent g⁻¹ dry tissue weight in boiled pith tissue to a high of 17.7 mg chlorogenic acid equivalent g⁻¹ dry tissue weight in raw skin tissue. The antioxidant capacity was highest in raw skin tissue (22.9 mg Trolox equivalent g⁻¹ dry tissue weight). Chlorogenic acid was the principal phenolic acid found in all sweetpotato tissues. Caffeic acid and three isomers of dicaffeoylquinic acid (diCQA) were also identified and quantified.     

The effect of ultrasound-vacuum-assisted extraction on bioactive properties of pitaya (Hylocereus undatus)

This study aimed to investigate the effect of ultrasound-assisted extraction under vacuum on bioactive properties of peel and flesh of pitaya fruit, and also compare with sonication under atmosphere condition using the principal component analysis (PCA). Vacuum sonication exhibited better results for total phenolic (56.78–71.54 mg GAE per 100 g for peel; 11.03–17.92 mg GAE per 100 g for flesh) and total flavonoid (95.33–115.71 mg QE per 100 g for peel; 13.26–19.36 mg QE per 100 g for flesh) amounts. DPPH free radical scavenging activity values of peel and flesh increased from 1.97 to 2.53 mmol TE kg^-1; from 0.33 to 0.50 mmol TE kg^-1 after sonication process, respectively. The main phenolic compounds of pitaya were identified as catechin (1.15–20.31 mg per 100 g) and rutin (0.88–14.55 mg per 100 g) in peel; catechin (1.11–9.35 mg per 100 g) and 3,4-dihydroxybenzoic acid (1.29–3.60 mg per 100 g) in flesh. The combination of vacuum and ultrasound process can be used as a green extraction technology in order to enhance the amounts of bioactive compounds of pitaya fruit.     

Acerola and cashew apple as sources of antioxidants and dietary fibre

Several tropical fruits have been described as natural sources of dietary fibre (DF) and phenolic compounds, associated with different health effects. The aim of this work was to ascertain the DF, phenolic compounds content (including non‐extractable polyphenols, mostly associated with DF) and antioxidant capacity in acerola fruits and cashew apples from selected clones. ‘BRS 236’ acerola fruits presented a high antioxidant capacity because of the combination of both extractable polyphenols and l ‐ascorbic acid (providing together a Folin value of 170 kg^?1 g d.m.). ‘CCP 76’ cashew apples contained 28 g kg^?1 d.m. of extractable polyphenols and 13 g kg^?1 d.m. of ascorbic acid as well as a high amount of non‐extractable condensed tannins (52 g kg^?1 d.m.). DF content was of 260 g kg^?1 d.m. in acerola fruit and of 209 g kg^?1 d.m. in cashew apple. Acerola fruits and cashew apple should therefore be considered as new natural sources of DF and phenolic compounds.     

不同成熟期蜜桔中酚酸的组成与分布

酚酸具有多种生理功能,在植物中广泛存在.柑橘可能是膳食酚酸的重要来源.采用HPLC-PDA测定了不同成熟期温州蜜桔中八种酚酸的含量,即绿原酸、咖啡酸、对香豆酸、阿魏酸、芥子酸、原儿茶酸、对羟基苯甲酸和香草酸.结果显示,果肉中酚酸含量随成熟度提高而减少,果皮酚酸含量在半成熟期最高;果皮中酚酸含量大大高于果肉;果皮果肉中都以肉桂酸型酚酸为主,苯甲酸型酚酸含量较少;蜜桔果实中绿原酸和阿魏酸是所测八种酚酸中含量最高的.对柑橘中酚酸组成与分布的研究可望应用于食品营养标识、柑橘品种的识别或加工果汗掺假的识别等.     

Antioxidant activity,fatty acids and phenolic acids compositions of potato peels

The effects of freeze-dried extracts from the peels of six potato varieties as antioxidants in pure soy oil were investigated using the active oxygen method (AOM) procedure, carotene bleaching and linoleic acid oxidation experiments on thin-layer chromatography (TLC) plates. At 9 h under AOM conditions, 20 g soy oil treated with 0.05 g of these extracts attained lower peroxide values (PV, 22.0-28.0 meq kg^?1) than the control oil sample (PV, 109.0 meq kg^?1) indicating very strong antioxidant activities. Oils treated with the same amount of tertiary butylhydroquinone, butylated hydroxyauisol-butylated hydroxytoluene mixture and rosemary extract attained PV of 10, 19.0 and 16.0 meq kg^?1, respectively. Results of the carotene bleaching and linoleic acid oxidation experiments on TLC plates indicated that the antioxidant activities of these extracts were due to the presence of phenolic acids. Among the phenolic acids separated and identified by both high-performance liquid chromatography and TLC, chlorogenic, proto-catechuic and caffeic acids were predominant and appeared to be mainly responsible for the strong antioxidant activities of the extracts. Peels from the red potatoes contained more polyphenols than those from the brown-skinned varieties, but their oil contents were similar.     

不同品种李子多酚组成及抗氧化活性

为研究不同品种李子果皮、果肉多酚组成及抗氧化活性,以9个不同品种的李子(芙蓉李、巫山李、玫瑰李、红布李、黑布李、西梅李、脆红李、江安李、青李)为原料,提取游离酚和结合酚,测定其1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除能力和抗氧化能力(oxygen radical absorbance capacity,ORAC)值,并通过高效液相色谱分析其多酚组成。结果显示:9种李子果皮总酚含量范围为111.52~775.88 mg GAE/100 g;果肉总酚含量范围为120.65~301.91 mg GAE/100 g,其中红布李果皮、果肉总酚含量均最高,西梅李总酚含量均最低。在多酚组成上,游离酚含量显著高于结合酚,且多酚组分主要为酚酸(原儿茶酸、绿原酸、咖啡酸)。体外抗氧化结果显示:9种李子果皮、果肉多酚均具有一定的抗氧化活性,DPPH自由基清除IC50值范围为4.38~46.46μg/m L,ORAC值范围为0.24~210.50μmol TE/g,其中巫山李果肉游离酚对DPPH自由基的清除能力最强,红布李果皮游离酚ORAC值最高。     

The effect of postharvest 1-MCP treatment and storage atmosphere on ‘Cripps Pink’ apple phenolics and antioxidant activity

This study investigated the effect of a postharvest 1-methylcyclopropene (1-MCP) treatment, controlled atmosphere and storage time on the total antioxidant activity (TAA) and phenolic compounds in the peel and flesh of ‘Cripps Pink’ apples (Malus domestica Borkh.). Preclimacteric apples were harvested and treated with 1-MCP then stored in normal atmosphere (NA) or controlled atmosphere (CA) at 0 °C for up to 160 days. In general, the level of phenolics decreased by 9% in the peel and significantly increased twofold in the flesh during cold storage, regardless of storage atmosphere or 1-MCP treatment. However, treatment with 1-MCP resulted in significantly lower concentrations of chlorogenic acid and procyanidin B2 in apple flesh, and catechin and epicatechin in the peel compared to the control fruits. There was no significant effect of CA on the phenolic compounds during long-term storage, except for quercetin 3-galactoside and quercetin 3-glucoside, which both significantly increased under CA storage. Total antioxidant activity (TAA) is an important nutritional attribute of apples in the human diet. The results showed that TAA in the peel tissue was about eight times higher than that of the flesh, with mean values of 4.75 g TE/kg FW and 0.56 TE/kg FW, respectively. The TAA in both the peel and flesh tissue increased significantly during storage by 40% and 70%, respectively. The storage atmosphere did not significantly affect TAA in either the peel or flesh, whilst the 1-MCP treatment significantly reduced the TAA in the peel tissue only. These results show the beneficial combined effects of pre-storage 1-MCP treatment and CA on ‘Cripps Pink’ apple phenolic composition and antioxidant capacity during long term storage.     

Comparison of antioxidant capacity and phenolic composition of peel and flesh of some apple varieties

BACKGROUND: Apples contain a large concentration of phenolic compounds, dependent on factors such as cultivar, harvest, storage conditions, and processing. This study aims to identify the essential phenolic compounds present in various apple varieties, to measure their total antioxidant capacity (TAC) with the CUPRAC (cupric ion reducing antioxidant capacity) and ABTS (2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonate)) methods, and to correlate their TAC values with HPLC findings. RESULTS: The order of TAC (mmol Trolox g^?1 fresh weight) of apple peels determined with the CUPRAC method was: Granny Smith > Amasya > Sky Spur > Ervin Spur > King Luscious ≥ Arap Kizi ≥ Lutz Golden. The theoretically calculated TAC values of HPLC‐quantified compounds, with the aid of the combined HPLC‐CUPRAC method, accounted for 18.4–33.5% of the experimentally observed CUPRAC capacity of peel extracts and 19.5–56.3% of flesh extracts, depending on apple variety. CONCLUSION: In synthetic samples of apple antioxidants, the CUPRAC‐TAC values of constituents, identified and analyzed by HPLC, proved to be additive, enabling measurement of the cooperative action of antioxidants using the proposed methodology. Apple peel showed higher contents of phenolics and therefore higher TAC than apple flesh, confirming the health benefit of the consumption of apples together with peel. © 2012 Society of Chemical Industry     

Phenolic compounds and antioxidant activity of tuberous root leaves

The antioxidant potential of five tuberous root leaves was evaluated. High performance liquid chromatography (HPLC/DAD) showed the presence of phenolic compounds in leaves, and the predominant ones were chlorogenic acids in carrot (458.79 mg.L^?1± 0.03): rosmarinic acid in sweet potato (222.05 mg.L^?1± 0.01) and quercetin in sweet potato (292.42 mg.L^?1± 0.01). Radish leaves showed a higher total in vitro antioxidant activity for all methods used in this study. The results indicated that these leaves were natural sources of antioxidants and, therefore, could be included in the health beneficial diet.     

Effects of germination on nutritional composition of waxy wheat

BACKGROUND: Germination is considered to improve the nutritive value, antioxidant capacity and functional properties of grains. In this study, changes in the chemical composition, nutritive value and antioxidant capacity of waxy wheat during germination were determined. RESULTS: Over a 48 h period of germination the protein and free lipid contents of germinated waxy wheat were not significantly different from those of the control, whereas the bound lipid content decreased significantly. An increase in levels of ash and dietary fibre was clearly observed for the 48 h‐germinated wheat. The total free amino acid content of the 48 h‐germinated wheat was 7881 mg kg^?1 flour (dry basis (d.b.)), significantly higher than that of the ungerminated wheat (2207 mg kg^?1 flour, d.b.). In particular, γ‐aminobutyric acid increased from 84 mg kg^?1 flour (d.b.) in the control to 155 mg kg^?1 flour (d.b.) in the 48 h‐germinated wheat. Germination did not significantly affect the fatty acid composition of both free and bound lipids of waxy wheat, whereas free phenolic compounds increased during germination, resulting in an increase in antioxidant capacity of germinated wheat. CONCLUSION: Germinated waxy wheat had a better nutritional composition, such as higher dietary fibre, free amino acid and total phenolic compound contents, than ungerminated waxy wheat. Therefore germinated waxy wheat should be used to improve the nutritional quality of cereal‐based products. Copyright © 2011 Society of Chemical Industry     

Phytochemical constituents and antioxidant capacity of different pecan [Carya illinoinensis (Wangenh.) K. Koch] cultivars

Six pecan cultivars were analyzed for their antioxidant capacity (AC), total phenolics (TP), condensed tannin (CT), HPLC phenolic profile, tocopherol and fatty acid composition. Kernels which included the outer brown testa or pellicle, and shells which is the hard cover that surrounds the kernel, were evaluated for each cultivar. Strong correlations were found in kernels between AC and TP for both DPPH (r² = 0.98) and AC_ORAC (r² = 0.75) antioxidant assays. AC_ORAC values ranged from 372 to 817 μmol trolox equivalents/g defatted kernel, corresponding to Desirable and Kanza cultivars, respectively. CT ranged from 23 to 47 mg catechin equivalents/g defatted kernel and TP from 62 to 106 mg of chlorogenic acid equivalents/g defatted kernel. After a consecutive basic-acid hydrolysis, gallic acid, ellagic acid, catechin and epicatechin were identified by HPLC. The TP, AC and CT were 6, 4.5 and 18 times higher, respectively, for shells compared to kernels. The presence of phenolic compounds with high antioxidant capacity in kernels and shells indicates pecans can be considered an important dietary source of antioxidants.