Hibiscus sabdariffa L. una fonte sostenibile di antocianine. Caratterizzazione fitochimica e attività antiossidante di estratti dai calici

The present research involves the quali-quantitative characterization and the antioxidant activity of two extracts from Hibiscus sabdariffa L. species. The research activities were carried out on the calyxes from two different varieties of the same species, called respectively kibeleza and tenonderà. The plants, grown in Paraguay, were supplied by the company Edynea Srl. Two batches of raw material were studied; harvesting and drying took place at two different times of the year. The work began with the identification of the most performing extraction method. Subsequently, analyses were carried out to establish the total monomeric anthocyanin content through the differential pH spectrophotometric method, and the total phenol content through the Folin-Ciocalteu method. It was decided to test the antioxidant activity of the extracts of Hibiscus sabdariffa L. as it is an interesting valuation for a possible cosmetic application. The DPPH and ABTS methods were performed, as well as the FRAP analysis. The qualiquantitative characterization of the extracts was performed by HPLC analysis. The characterization of these matrices and the detection of antioxidant activity are an innovative and preliminary study of the use of Hibiscus sabdariffa L. in nutri-cosmetic preparations.