Contents lists available at ScienceDirect Industrial Crops & Products journal homepage: www.elsevier.com/locate/indcrop Variation of biochemical and antioxidant activity with respect to the part of Capsicum annuum fruit from Tunisian autochthonous cultivars Karima Lahbib a , Samia Dabbou b,c, ⁎ , Safia EL Bok a , Gaetano Pandino d , Sara Lombardo d , Mohamed EL Gazzah a a Laboratory of Biodiversity, Biotechnology and Climatic Change, Faculty of Sciences of Tunis, University of Tunis El Manar, 2092 El Manar II, Tunis, Tunisia b Laboratory of Bioresources, Integrative Biology and Valorisation, Higher Institute of Biotechnology of Monastir, Av. Tahar Hadded, BP 74, 5000 Monastir, University of Monastir, Tunisia c Dentistry Faculty, Avicenne Street, 5019 Monastir, University of Monastir, Tunisia d Department of Agriculture, Food and Environment, University of Catania, via Valdisavoia 5, 95123 Catania, Italy ARTICLE INFO Keywords: Capsicum annuun Fruit part Phenols Capsaicin Antioxidant activity Chemometric analysis ABSTRACT Pepper is a good source of bioactive compounds and has an important role in the Mediterranean diet as a health- promoting food. Thus, this study was carried out with the aim to evaluate differences among fruit parts (pericarp, placenta and seed) in terms of total phenols and flavonoids content, capsaicin content and antioxidant activity in eleven cultivars grown in Tunisia. The antioxidant activity of the samples was measured by both 2,2- diphenyl-1-picrylhydrazyl (DPPH) and ferrous reducing antioxidant power (FRAP) assays. Overall, significant differences were observed in relation to the cultivar and fruit parts. In particular, the pericarp exhibited the highest levels of total phenols (6.82 ± 0.39 mg GAEg -1 DW) and flavonoids (0.46 ± 0.03 mg NAEg -1 ), whereas placenta showed the highest content of capsaicin (0.83 ± 0.07 mg -1 DW). Total phenols and flavonoids appeared to be the main contributors to the antioxidant activity in the pericarp, while capsaicin mainly contributed to the antioxidant capacity in the placenta. The fruit parts of Tunisian pepper cultivars demonstrated a high diversity of bioactive compounds, that should be exploited for food and pharmaceutical applications, meantime our data also encouraged the consumption of placenta and seeds. Finally, such wide variability among Tunisian pepper cultivars might represent a good tool for further breeding programs. 1. Introduction The Capsicum genus belongs to the Solanaceae family and includes peppers with important economic value (Giuffrida et al., 2013). They are very popular spices in various parts of the world, mainly due to their attributes of color, pungency and aroma (Bogusz Junior et al., 2015; Sousa et al., 2006). In Tunisia peppers are one of the most popular fruits, grown throughout the country, and show a wide variation in relation to the size, flavor and pungency. The main domesticated species of Capsicum peppers is Capsicum annuum L., which are known to be consumed fresh, dried, preserved or in spicy sauces as well as coloring and flavor agents in different types of foods (Bogusz Junior et al., 2015; Pino et al., 2007). Their color vary from green, yellow, orange, red, to black (Long-Solís, 1998). Green peppers are harvested before reaching the full maturity and have a slightly bitter flavor than red peppers. Yellow and orange peppers are more mature than green ones, while red peppers are collected at full maturity and have a sweet taste (Mitic et al., 2013). In general, the consumers prefer to consume the pericarp of the fruit and discard placenta and seeds. Pepper fruits are an excellent source of secondary metabolites, including vitamin C, carotenoids, capsicinoids and flavonoids (Korkutata and Kavaz, 2015; Wahyuni et al., 2013; Zhuang et al., 2012). Being in plant of pepper, these natural products were used in traditional medicine as a source of treatment of primary healthcare. With increase of medicinal plants usage, metabolites and bioactive components are being probed and targeted as novel pharmaceutical leads (Zengin et al., 2017). Peppers are the only plant genus able to produce capsaicinoids, which are responsible for their typical pungency. Capsaicin is the most predominant and naturally occurring alkamide found in Capsicum fruits, reaching around 90% of total capsaicinoids with dihydrocapsai- cin (Barbero et al., 2008; De Aguiar et al., 2013). The potential applications of capsaicin range from food flavorings to therapeutics. Previous records suggest pleiotropic pharmacological activities of capsaicin such as an analgesic, anti-obesity, anti-pruritic, anti-inflam- matory, anti-apoptotic, anti-cancer, anti-oxidant, and neuro-protective http://dx.doi.org/10.1016/j.indcrop.2017.04.037 Received 14 November 2016; Received in revised form 31 March 2017; Accepted 20 April 2017 ⁎ Corresponding author at: Dentistry Faculty, Avicenne Street, 5019 Monastir, University of Monastir, Tunisia. E-mail address: dabbou_samia@yahoo.fr (S. Dabbou). Industrial Crops & Products 104 (2017) 164–170 0926-6690/ © 2017 Elsevier B.V. All rights reserved. MARK