Hibiscus sabdariffa L.: phytoconstituents, nutritive, and pharmacological applications

Abstract

Hibiscus sabdariffa L. (HS) calyx extracts have been well-documented for the treatment of hypertension, liver dysfunctions, and diabetes among others. An updated concise review of HS regarding phytoconstituents, and involved putative mechanisms of potential biological activities is presented. HS showed other food and other industrial applications, including the preparation of metallic nanoparticles. These activities were explained by the presence of a broad spectrum of valuable phytochemicals, including the red pigments anthocyanins, phenolic, and organic acids and polyphenolics (e.g., flavonoids and tannins). Most of the bioactivities were found to be associated with anthocyanins-rich extracts. Anthocyanins were found to have various mechanisms for the treatment of hypertension, including direct vasodilation and inhibition of angiotensin-converting enzyme (ACE). However, leaves and seeds showed also other potential applications in food industry, owing to the significant amounts of phenolic antioxidant compounds. Therefore, valorization and optimization of bioactive constituents’ extraction from plant biowastes should be considered for maximizing the benefits of HS extracts.