ABSTRACT
Being the most widely distributed secondary metabolites in plants, phenolic and polyphenolic compounds in food and nutraceuticals exert their beneficial effect as free radical scavengers and metal chelators, thereby preventing oxidation of low-density lipoproteins and DNA strand scission and improve immune function (Shahidi and Naczk, 2004). Due to their properties, these food components have strong chemopreventive properties against the most common contemporary human diseases, such as cardiovascular diseases, cancer, and neurodegenerative pathologies (Latruffe et al., 2014). Polyphenols contribute to the organoleptic properties of plant-based foods, especially due to their astringency, bitter taste, color, and by their participation in haze formation (Le Bourvellec and
Renard, 2012). A wide range of phenolic compounds, such as phenols, benzoic acid derivatives, phenylpropanoids, flavonoids, stilbenes, tannins, lignans, and lignins can be found in plants and foods (Lättia et al. 2011). Probably, the most studied compounds from the perspective of functionality in human diet are flavonoids. The structure of flavonoids (2-phenyl benzopyran skeleton) is characterized by the presence of a basic skeleton C6-C3-C6, with two aromatic rings and a heterocyclic ring, the later containing one oxygen atom. Flavonoids are known for their wide range of biological effects including antioxidant, antibacterial, antiviral, anti-inflammatory, antiallergic, antiestrogenic, and anticarcinogenic capacities (Cook and Samman, 1996; Middleton et al., 2000; Heim et al., 2002; Nandave et al., 2005). The use of flavonoids in different matrices is limited due to their low bioavailability caused by the poor water solubility (Manach et al., 2005). It has been suggested that the bioavailability of these compounds can be increased through the use of proteins able to complex flavonoids (Gholami and Bordbar, 2014).
