A North Cameroonian cultivar of Hibiscus sabdariffa (Malvaceae) with calyces enriched in anthocyanins

Abstract

Folere (Hibiscus sabdariffa L.) is a traditional plant cultivated in the north of Cameroon near the city of Yagoua. Calyces are used to prepare beverages while the leaves are incorporated into meals. This Cameroonian roselle is characterized by a higher intensity of red color than that found in conspecific samples from Egypt, and it was of interest to us to evaluate its beneficial activities in comparison with European pharmacopoeia standards. The samples were first subjected to phylogenetic analyses. Five samples including samples from Egypt and a white flower variety were subsequently examined according to the European pharmacopeia criteria i.e. (i) taxonomic identification, (ii) sample preparation and characterization (desiccation, TLC, coloring power, presence of foreign matter), and (iii) determination of the acidity index. Anthocyanins and anthocyanidins were obtained using three extracts from methanolic maceration, infusion, and boiling in water. Taken together, the results confirmed that the Cameroonian variety indeed belongs to H. sabdariffa and meets European Pharmacopoeia standards. All extracts contained common anthocyanins (delphinidin-3-sambioside, delphinidin-3-glucoside, cyanidin-3-sambioside, cyanidin-3-glucoside), and delphinidin and cyanidin aglycones were also found in the organic extracts. As a result of determining the amount of anthocyanins by HPLC in Cameroon samples, it was determined that they showed a high concentration of delphinidin type anthocyanins and a concentration 10 times higher than the Egyptian variety. This variety appears to be a very promising candidate for inclusion in industrial preparations, thanks to its high anthocyanin qualitative and quantitative properties, and also maintains economic interest for local populations.