Sun protection is a complex topic, which involves various classes of compounds. The photoprotective effectiveness of a sunscreen involves many biological activities, such as ultraviolet (UV) radiation filter properties and antioxidant, anti-inflammatory, and antimutagenic effects. Formulation strategy is also a key factor. Several studies have examined the role of natural molecules as photoprotective compounds, and a considerable number of commercially available sunscreens contain herbal extracts but not as sunfilters. Indeed, the process of evaluation of UV-filtering and photoprotective activity of herbal compounds presents certain specific difficulties and needs in vitro and in vivo studies. Nowadays, no natural compound or vegetal extract has been approved by any country as official UV filter for sunscreen. With these premises, the aim of this chapter is to define a set of tests, which can help to evaluate the efficacy of an herbal extract in the field of sun protection; in other words, we propose a rational approach to the discovery of natural UV-filtering extract and molecules. The following electronic databases have been used as a source of information: SciFinder, PubMed, Google Scholar, ISI-Web of Science, and Scopus.
Part of the book: Herbal Medicine