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Claire H. Luby, Rachael Vernon, Hiroshi A. Maeda and Irwin L. Goldman

Vitamin E is a group of eight lipid-soluble antioxidants (α-, β-, γ-, and δ- tocopherols and tocotrienols, collectively known as tocochromanols) that are synthesized in the plastids of plants, algae, and some cyanobacteria ( Mène-Saffrané and

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Thomas C. Koch* and Irwin L. Goldman

Carotenoids (provitamin A) and tocopherols (vitamin E) are powerful antioxidants in plants and in the human diet. Carrot (Daucus carota) has been selected for increased levels of carotenoids, contributing to its orange color and reported health benefits. Selection for increased tocopherol has shown success in seed oils, but little progress has been made in the edible portions of most vegetable crops. HPLC measurement following a simultaneous heptane extraction of both compounds has shown a significant (P ≤ 0.001) positive correlation of α-tocopherol with α-carotene (r = 0.65) and β-carotene (r = 0.52). To increase both the tocopherols and carotenoids in plants, 3 populations have been established from select open-pollinated varieties grown in 2002. These populations consist of half-sib families with these differing selection schemes: based strictly on increased α-tocopherol levels; an index to increase α-carotene, β-carotene and α-tocopherol; and a random population in which no selection is occurring. After one cycle of selection, populations were grown on muck soil during the summer of 2003. Compared with the random population, an increase of 24.68% in α-tocopherol concentration was recorded for the population selected strictly on α-tocopherol while increases of 8.47% in α-tocopherol, 9.31% in α-carotene and 7.31% in β-carotene were recorded for the population with index selection. The continuation of these carrot populations shows promise to produce carrot germplasm with improved human nutritive value.

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Cristián Vela-Hinojosa, Héctor B. Escalona-Buendía, José A. Mendoza-Espinoza, Juan M. Villa-Hernández, Ricardo Lobato-Ortíz, Juan E. Rodríguez-Pérez and Laura J. Pérez-Flores

Tomato fruit are an excellent source of antioxidants and contribute significantly to human health because of their anti-inflammatory, antiallergenic, and antithrombotic properties. Carotenoids and tocopherols are among the major lipophilic

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Vanessa E.T.M. Ashworth, Haofeng Chen, Carlos L. Calderón-Vázquez, Mary Lu Arpaia, David N. Kuhn, Mary L. Durbin, Livia Tommasini, Elizabeth Deyett, Zhenyu Jia, Michael T. Clegg and Philippe E. Rolshausen

from ground level to the tip of the tree. Canopy diameter was determined at the widest part of the canopy in two orientations: parallel to the orchard row and perpendicular to the row, with the two values averaged. Fruit nutrient composition [α-tocopherol

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Myung-Min Oh, Edward E. Carey and C.B. Rajashekar

, including α-tocopherol, β-carotene, and flavonoids, in a wide range of plant species ( Keles and Öncel, 2002 ; Munné-Bosch et al., 2001 ; Tattini et al., 2004 ; Zobayed et al., 2007 ). Because lettuce is the most commonly consumed fresh leafy vegetable

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Carmen Mena, Alejandra Z. González, Raúl Olivero-David and María Ángeles Pérez-Jiménez

methanol extraction and subsequent reaction with Folin–Ciocalteu reagent and measured at a wavelength of 725 nm ( Vázquez-Roncero et al., 1975 ). Results are expressed as milligrams of caffeic acid equivalents per kilogram of oil. Total tocopherol content

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Shiva Ram Bhandari, Bo-Deul Jung, Hum-Young Baek and Young-Sang Lee

and dihydrocapsaicin were obtained from Fluka. Standards for fatty acid methyl ester were acquired from Supelco, and vitamin E (α-, β-, γ- and δ-tocopherols) standards were purchased from Merck (Germany). Chemicals such as acetonitrile, acetic acid, n

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Charles R. Brown, David Culley, Meredith Bonierbale and Walter Amorós

as nanoMoles of α-tocopherol equivalents/100 g FW. Statistical analysis. Analysis of variance following a randomized complete block design and Duncan's multiple range test was applied to the means ( Steel and Torrie, 1980 ). Correlations were

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J.O. Kuti

Flavonoid content and antioxidant activity in peel and pulp samples of four different cactus pear fruit varieties were investigated. Major cactus fruit flavonoids were quercetin, kaempferol, and isorhamnetin. Greater amount of quercetin was found in the pulp compared with the peel samples in all varieties examined. Both kaempferol and isorhamnetin were found in at least three of the varieties (Opuntia ficus-indica; O. lindheimeri; O. streptacantha) exclusively in the peel samples. Generally, pulp tissue samples of all the cactus fruit varieties contained greater ascorbic acid, glutathione, alpha-tocopherol and beta-carotene and antioxidant activities than the peel tissue samples. Total flavonoids correlated well with antioxidant activity (r 2 = 0.89). Ascorbic acid had the highest antioxidant activity, followed by glutathione, beta-carotene, and alpha-tocopherol on equimolar basis.

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Jose E. Villarreal, Leonardo Lombardini and Luis Cisneros-Zevallos

Pecans nuts from `Kanza' and `Desirable' cultivars were irradiated with 0, 1.5, and 3.0 kGy using electron beam (E-beam) irradiation and stored under accelerated conditions (40 °C and 55% to 60% RH). Antioxidant capacity (AC), phenolic (TP) and condensed tannin (CT) content, HPLC phenolic profile, tocopherol content, peroxide value (PV), and fatty acid profile were evaluated in kernels after 0, 7, 21, 55, and 134 days of storage. Irradiation had no detrimental effects in AC and TP; however, variation was found throughout storage. Tocopherol content of 1.5 and 3.0 kGy kernels decreased after irradiation, but no further decrease was observed thereafter. Irradiated `Desirable' samples had greater PV than controls, while `Kanza' 1.5 kGy samples had increased PV only after 134 days of storage. No change in fatty acid composition was detected for any cultivar. Color modification induced by storage included a decrease in lightness and yellowness and an initial increase of redness followed by a decrease after 98 days of storage. No differences in phenolic profile were observed after irradiation. Compounds identified by HPLC in hydrolyzed extracts were gallic and ellagic acid, catechin, and epicatechin. In general, beside the decrease in tocopherol content, no detrimental effects were found in antioxidant composition caused by irradiation treatments. While a faster oxidation rate was seen in irradiated kernels for `Desirable' cultivar, no other quality attribute was affected by E-beam irradiation.