Bioactive compounds in plants: a new food perspective

Antioxidants refer to a group of compounds that are able to delay or inhibit the oxidation of lipids or other biomolecules, and thus prevent or repair the damage of body cells caused by oxygen (Shahidi and Naczk, 2004; Tachakittirungrod et al., 2007). The ever-increasing consumer sensitivity to the consumption of food with lower content of synthetic chemical products and the loss of efficacy of common preservatives due to the development and diffusion of resistant bacteria, have led to increasing research activities regarding the extraction and the evaluation of the efficacy of natural antioxidants. For this reason, there is a growing interest in the studies of natural healthy (nontoxic) additives as potential antioxidants (Tomaino et al., 2005), such as Extracts and Essential Oils (EOs). In this work was evaluated the antioxidant activity of extracts from Coriandrum sativum L., Cannabis sativa L, and Thymus vulgaris L., through the main in vitro assays, such as FRAP, ABTS, DPPH and total phenolic and flavonoid contents (Zou et al., (2004), Hanato et al. (1988), Dewanto et al. (2002)). The antioxidant potentialities of these species were compared evaluating four different extracts, produced by means of Sohxlet, Naviglio, maceration and ultrasounds. The results obtained from this preliminary study, allowed to establish that best antioxidant activity was recorded for extracts obtained by means of Sohxlet extraction technique. The recorded antioxidant potentials allowed also to establish that these extracts could be good candidates as food preservatives, delaying food oxidation and increasing products shelf-life.