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R. Maestro, J.M. García, and J.M. Castellano

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Guiwen W. Cheng and Carlos H. Crisosto

The formation of metallo-pigmentation and copigmentation as potential mechanisms of inking formation was investigated in peach and nectarine skin tissues. Cyanidin-3-glucoside, the most abundant anthocyanin in peaches and nectarines, formed very purple ferric complexes with an anthocyanin/iron molar ratio of two. Greenish metallo complexes between ferric ion and chlorogenic acid, caffeic acid, catechin, or epicatechin formed with an phenolic/iron molar ratio of one. The lack of copigmentation pointed out the importance to focus research on the metallo-phenolics reaction. High intensity of dark color formation was developed with cyanidin-3-glucoside, followed by caffeic acid, chlorogenic acid, catechin, and epicatechin on an equal molar basis. Citric acid acted as a strong iron chelator to prevent and reverse the formation of ferric cyanidin-3-glucoside complexes. The variety of dark and light colored spots observed on the surface of peaches and nectarines is explained by the formation of metallo-pigment complexes.

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L. Mark Lagrimini, Jill Vaughn, W. Alan Erb, and Sally A. Miller

Lignin composition in leaf, fruit, and fruit outer epidermis of transgenic tomato (Lycopersicon esculentum Mill.) plants that overproduce the enzyme tobacco anionic peroxidase (TobAnPOD) was analyzed. This enzyme may catalyze the polymerization of cinnamyl alcohols into lignin in tobacco (Nicotiana tabacum L.); therefore, we predicted that its presence in the transformed tissue would increase lignin levels in healthy and wounded tissue. Lignin levels in healthy plants increased by 20% in leaf, 49% in fruit, and 106% in fruit outer epidermal tissue. Mature-green fruit were aseptically wounded and incubated in darkness for up to 7 days. Soluble phenols in wounded transgenic fruit increased by more than 300% hut changed little in control fruit. As with soluble phenols, lignin content in wounded transformed fruit increased by more than 20-fold hut increased less than two-fold in control fruit. Transgenic seedlings overproducing TobAnPOD were screened for susceptibility to several pathogens, but resistance did not increase. Possible TobAnPOD roles in lignin biosynthesis, phenol metabolism, stress response, and disease resistance are discussed.

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Gregory Peck, Megan McGuire, Thomas Boudreau IV, and Amanda Stewart

index (SPI) and internal ethylene concentration (IEC), fruit quality factors are often measured to gauge harvest maturity ( Watkins, 2003 ). For cider production, fruit quality attributes also include polyphenol and YAN concentrations in the fruit, and

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Attila Ombódi, Noémi Koczka, Andrea Lugasi, Hussein Gehad Daood, Mária Berki, and Lajos Helyes

examine the influence of irrigation on dry matter concentration, storage carbohydrates, vitamin C, total flavonols and polyphenols of onions raised from sets compared with a rain-fed control. Materials and Methods Experimental conditions and plant material

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Camila P. Croge, Francine L. Cuquel, Paula T.M. Pintro, Luiz A. Biasi, and Claudine M. De Bona

compounds ( Moyer et al., 2002 ). Heinonen et al. (1998) found the highest indices of polyphenols and a higher capacity to inhibit human low-density lipoprotein (LDL) degradation (a characteristic related to antioxidant activity) in blackberries compared

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Youssef Rouphael, Mariateresa Cardarelli, Luigi Lucini, Elvira Rea, and Giuseppe Colla

polyphenols concentration in ‘Romolo’ artichoke and ‘Bianco Avorio’ cardoon cultivars grown in a floating system. Materials and Methods Plant material and growth conditions The experiment was conducted in the Summer and Fall 2011 in a 300-m 2 polyethylene

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Ryohei Koyama, Hiromichi Itoh, Syuji Kimura, Ai Morioka, and Yuichi Uno

than any other food ( Gupta and Prakash, 2008 ). Plants can synthesize some antioxidants including, for example, AsA, glutathione, α-tocopherol (vitamin E), and polyphenol to protect themselves against oxidative damage caused by environmental stressors

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

nm were quantified as gallic acid-equivalent, whereas flavonoids were quantified as rutin-equivalent. Determination of total polyphenol content, antioxidant capacity, and nitrate. Chemicals. Chemicals were methanol (AnalaR Normapur), Folin

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Fang Xiao, Zaiqiang Yang, Haijing Huang, Fei Yang, Liyun Zhu, and Dong Han

increase photosynthetic rate ( Haukioja et al., 1998 ), nonstructural carbohydrate accumulation ( Wanyoko, 1983 ), and biosynthesis of C-based secondary metabolites ( Haukioja et al., 1998 ). They also found that the total polyphenol concentrations in green