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Weiguang Yi and Hazel Y. Wetzstein

). For calibration, Trolox (6-hydroxy-2,5,7,8-tetramethychroman-2-carboxylic acid, a vitamin E analog) standards of 0, 300, 600, 900, 1200, and 1500 μM were used. The TEAC of the sample was calculated based on the inhibition exerted by the standard Trolox

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Zoltán Pék, Hussein Daood, Magdolna Gasztonyi Nagyné, Mária Berki, Marianna Márkus Tóthné, András Neményi, and Lajos Helyes

al.’s (1995) method was used. The DPPH stabile-free radical was reacted with the sample extract in a relevant dilution at 36 °C for 30 min. The antioxidant activity is given in TEAC (mmol·kg −1 ). Statistical analysis All samples were measured in

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Djamila Rekika, Shahrokh Khanizadeh, Martine Deschênes, Audrey Levasseur, Marie Thérèse Charles, Rong Tsao, and Raymond Yang

Eighteen strawberry genotypes were evaluated for their phenolic content and antioxidant capacity using several methods. High antioxidant capacity was found for `Harmonie', `Saint-Jean d'Orléans', and `Saint-Laurent d'Orléans', which were reported to have better shelf life than `Kent'. `Harmonie', `Saint-Jean d'Orléans', `Orléans', and some advanced selections had higher hydroxycinnamic acids, benzoic acids, and flavonols than `Kent'. The significant variation in antioxidant capacity and total phenolic compounds clearly shows the potential value of certain new cultivars and advanced lines as parents in a breeding program. The future plan is to examine individual antioxidant and their role in disease resistance and extension of shelf life and to use selected genotypes as parents to developed new lines.

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Juan Carlos Díaz-Pérez, Kelly St. John, Mohammad Yamin Kabir, J. Alberto Alvarado-Chávez, Ania M. Cutiño-Jiménez, Jesús Bautista, Gunawati Gunawan, and Savithri U. Nambeesan

extract and expressed as quercetin equivalents ( Rawat et al., 2014 ). Antioxidant capacity was determined by the TEAC and the CUPRAC methods ( Barros et al., 2007 ; Castro-Concha et al., 2014 ). Statistical analysis. Data were analyzed using the General

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Juan Carlos Díaz-Pérez and Kelly St. John

total antioxidant capacity following the Follin–Ciocalteau method ( Singleton et al., 1999 ), and data were expressed as gallic acid equivalents. Antioxidant capacity was determined by CUPRAC and TEAC methods ( Barros et al., 2007 ; Castro-Concha et al

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Floyd M. Woods, William A. Dozier, Robert C. Ebel, Raymond Thomas, Monte Nesbitt, Bryan S. Wilkins, and David G. Himelrick

Changes in fruit quality attributes and antioxidative properties from six cultivars of thornless blackberries (Rubus sp.) (`Apache', `Arapaho', `Chester', `Loch Ness', `Navaho', and `Triple Crown') during four different ripening stages (red, mottled, shiny-black, and dull-black) were determined under Alabama growing conditions. Berry fruit samples were evaluated for pH, titratable acidity, total soluble solids, TSS/TA ratio, soluble sugars, vitamin C (reduced, oxidized and total), and antioxidant capacity (measured as trolox equivalent antioxidant capacity, TEAC). Significant variation among cultivars were noted in fruit quality attributes and antioxidative properties, which were influenced by maturity at harvest. An increase in fruit pH concomitant with a decline in titratable acidity (TA) was observed during ripening for all cultivars. Total soluble solids (TSS) values increased from 5.7% to 11.6%, with associated TSS/TA ratio values ranging from 11.92 to 63.56 in ripening fruit. Highest reducing and total sugar content were contained in dull-black fruit. Vitamin C content either declined or remained unchanged with ripening, and the pattern was dependent on cultivar, maturity at harvest and form determined. In general, antioxidant activity declined between red and dull-black ripening stages. The results suggest that the TSS/TA ratio may provide the best maturity index in determining optimal eating quality and antioxidant capacity in terms of TEAC value the best indicator of optimal nutritional quality as influenced by maturity at harvest.

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Karen Salandanan, Marisa Bunning, Frank Stonaker, Oktay Külen, Patricia Kendall, and Cecil Stushnoff

-picrylhydrazyl (DPPH) as Trolox-equivalent antioxidant properties (TEAC), dry matter, and soluble solids concentration (SSC) in the same 10 cultivars grown in the same location, on the same soil texture and type, using organic and conventional practices for 2

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Juan C. Díaz-Pérez, Dan MacLean, Smiljana Goreta, Sarah Workman, Erick Smith, Harwinder Singh Sidhu, Gunawati Gunawan, Anthony Bateman, Jesús Bautista, William Lovett, Maja Jukić Špika, Gvozden Dumičić, and Mira Radunić

gallic acid equivalents. The antioxidant capacity was determined by the Trolox equivalent antioxidant capacity (TEAC) and the Cupric reducing antioxidant capacity (CUPRAC) methods ( Barros et al., 2007 ; Castro-Concha et al., 2014 ). The total

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

) antioxidant capacity [trolox equivalent antioxidant capacity (TEAC)] in lettuce leaves with plant age. Lettuce plants were grown at 22/18 °C (day/night), 250 μmol·m −2 ·s −1 PPF , and a 12-h photoperiod in a growth chamber. The values are the means of three

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Maedza V. Khathutshelo, Nkomo Mpumelelo, Ngezimana Wonder, and Mudau N. Fhatuwani

Trolox equivalent antioxidant capacity (TEAC) assay as described by Awika et al. (2004) . The chosen assay, TEAC, is a spectrophotometric technique that measures the relative ability of hydrogen-donating antioxidants to scavenge the 2, 2′-azino-bis3