Antioxidants as Nutraceuticals of Phytochemical Nature (Plant Natural Foods) in Disease Prevention and Therapy

Oxidative stress and its relation on the onset of several chronic diseases has been in-creasingly studied and highlighted in recent years. This fact has been concurrent with increased reports on the antioxidant properties of various phytochemicals derived from fruits, vegetables, herbs, or seaweed, which can be accessible by intake or obtained following chemical extraction from these sources. These phytochemicals are majorly the result of each plant’s secondary metabolism, out of which the main chemical groups include structural polysaccharides, unsaturated fatty acids (PUFAs), pigments (chlo-rophylls, carotenoids, anthocyanins) and chief among them, phenolic compounds. The structural features of each group allow them to act at different sites, levels, by different molecular mechanisms and display diverse effectiveness as chemo-preventive agents for various diseases. Beyond their antioxidant properties, these phytochemicals have been described to exert a plethora of chemo-preventive and therapeutic effects, in-cluding anti-inflammatory, antidiabetic, anti-obesity or neuroprotective, acting through various mechanisms and paths involved. This knowledge has led to the development of various nutraceuticals enriched in antioxidant phytochemicals to be used as functional ingredients in foods, or for their periodic separated intake, whether as enriched extracts, or isolated compounds of high efficacy. Overall, phytochemical antioxidants are attrac-tive biomolecules to be used as nutraceuticals of relevant chemo-preventive and ther-apeutic properties on the onset of various diseases related to antioxidant stress.