Phenolic compounds and fatty acids in different parts of Vitis labrusca and V. vinifera grapes Leandra Pereira Santos, Damila Rodrigues Morais, Nilson Evelázio Souza, Solange Maria Cottica, Marcela Boroski, Jesuí Vergílio Visentainer ⁎ Department of Chemistry, State University of Maringá, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná State, Brazil abstract article info Article history: Received 26 October 2010 Accepted 12 February 2011 Keywords: Grapes Antioxidant Phenolic compounds Resveratrol Fatty acids trans-Resveratrol, antioxidant activity, phenolic compounds, proximate composition, and fatty-acid composition were quantified in different parts (peel, pulp, and seeds) of four grape varieties: Brazil (Vitis vinifera), Benitaka (V. vinifera), Isabel (Vitis labrusca) and Niagara (V. labrusca). Large concentrations of polyunsaturated fatty acid (18.84 and 9204.27 mg 100 g -1 ), linoleic acid (LA, 18:2n-6), from 5890.87 to 9148.93 mg 100 g -1 , and alpha- linolenic (LNA, 18:3n-3), from 5.25 to 56.85 mg 100 g -1 , were found in different parts of the four grape varieties. The lowest concentrations necessary for 50% inhibition of DPPH were (9.26 to 126.91 μg mL -1 ) in seeds; the pulp did not have antioxidant activity. The total phenolic content varied between 0.04 and 122.35 mg EAG g -1 ; seeds had the highest concentrations (89.83 to 122.35 mg EAG g -1 ), especially in Niagara and Isabel varieties. trans- Resveratrol was detected in peels (1.17 to 12.96 μgg -1 ) and seeds (2.03 to 2.44 μgg -1 ) of the four varieties; however, it was absent in the pulp. Published by Elsevier Ltd. 1. Introduction The consumption of grapes and their derivatives has been associated with the prevention of certain diseases, such as cancer (Nandakumar, Singh, & Katiyar, 2008), cardiovascular diseases (due to the inhibition of the oxidation of low density lipoproteins (Frankel, Waterhouse, & Teissedre, 1995)), and Alzheimer's disease (Anastasiadi, Pratsinis, Kletsas, Skaltsounis, & Haroutounian, 2010). The benefits of grapes are associated with two factors: polyunsatu- rated fatty acids (PUFA) present mostly in seeds, as they prevent cardiovascular diseases (Yi et al., 2009) and, most importantly, with phenolic compounds, for their high antioxidant potential, and therefore, their capacity to prevent oxidation of biological substrates (Jacob, Hakimuddin, Paliyath, & Fisher, 2008). Among the phenolic compounds in grapes, resveratrol stands out due to recent findings showing its several biological effects, such as anticarcinogenic and anti-inflammatory activities (Gürbüz et al., 2007). Grape seeds and skins are good sources of phytochemicals such as gallic acid, catechin, and epicatechin and are suitable raw materials for the production of antioxidative dietary supplements (Yilmaz & Toledo, 2004). Grape seed extract is one of Japan's natural of additive, and is recommended for as an antioxidant. The component of interest is polyphenol, mainly proanthocyanidins (Nakamura, Tsuji, & Tonogai, 2003). The peel and seed fractions of fruits may potentially contain more antioxidants quantitatively or qualitatively than the pulp fractions (Guo et al., 2003). Furthermore, there is great interest on the crude extracts – from fruit and plant materials rich in phenolics – in the food industry, because they can retard oxidative degradation of lipids and thereby improve the quality and nutritive value of food (Moure et al., 2001) as an alternative source of antioxidant instead of use synthetic antioxidant. Some synthetic antioxidants have a carcinogenic effect; therefore, their use is limited or prohibited in some countries (Ramalho & Jorge, 2006). The objective of this study was to analyze peel, pulp, and seed extracts of four grape varieties, Isabel (Vitis labrusca), Niagara (V. labrusca), Benitaka (Vitis vinifera), and Brazil (V. vinifera), in terms of proximate composition, fatty acid composition, antioxidant activity, phenolic compounds and trans-resveratrol contents. 2. Materials and methods 2.1. Materials 2.1.1. Sampling Four grape cultivars: Isabel (V. labrusca), Niagara (V. labrusca), Benitaka (V. vinifera) and Brazil (V. vinifera), grown in Jales, São Paulo, Brazil, were obtained in 2009. All fruits were first flushed with tap water and then washed in distilled water for three times before the peel, pulp and seed fractions were carefully separated. The seeds were dried at ambient temperature (25 °C). The different parts were ground and Food Research International 44 (2011) 1414–1418 ⁎ Corresponding author. Tel.: +55 044 3261 3661; fax: +55 044 3011 4389. E-mail address: jvvisentainer@uem.br (J.V. Visentainer). 0963-9969/$ – see front matter. Published by Elsevier Ltd. doi:10.1016/j.foodres.2011.02.022 Contents lists available at ScienceDirect Food Research International journal homepage: www.elsevier.com/locate/foodres