Hibiscus sabdariffa L. as a source of nutrients, bioactive compounds and colouring agents

The nutritional and bioactive composition of plants have aroused much interest not only among scientists, but also in people's daily lives. Apart from the health benefits, plants are a source of pigments that can be used as natural food colorants. In this work, the nutritional composition of Hibiscus sabdariffa L. was analysed, as well as its bioactive compounds and natural pigments. Glucose (sugar), malic acid (organic acid), a-tocopherol (tocopherol) and linoleic acid (fatty acid) were the major constituents in the corresponding classes. 5-(Hydroxymethyl) furfural was the most abundant non-anthocyanin compound, while delphinidin-3-O-sambubioside was the major anthocyanin both in its hydroethanolic extract and infusion. H. sabdariffa extracts showed antioxidant and antimicrobial activities, highlighting that the hydroethanol extract presents not only lipid peroxidation inhibition capacity, but also bactericidal/fungicidal inhibition ability for all the bacteria and fungi tested. Furthermore, both extracts revealed the absence of toxicity using porcine primary liver cells. The studied plant species was thus not only interesting for nutritional purposes but also for bioactive and colouring applications in food, cosmetic and pharmaceutical industries.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013) and under Programme NORTE2020 for the project NORTE-01-0145-FEDER-023289, as also for L. Barros contract. The authors are also grateful to the Interreg España-Portugal for financial support through the project 0377_Iberphenol_6_E.