Characterization of carotenoids, proximal analysis, phenolic compounds, anthocyanidins and antioxidant capacity of an underutilized tuber ( Tropaeolum tuberosum) from Bolivia

The tubers of Tropaeolum tuberosum , locally known as Isaño and native to the Andean region of South America, have been known since ancient times for their multiple uses in the Bolivian population. They are used both as food in various preparations and in traditional medicine. In this investigation, we report the study of three Isaño cultivars currently consumed in Bolivia. We determined their proximal composition, characterized carotenoids, determined antioxidant capacity, measured total phenols and total flavonoids, and quantified the major polyphenols. The results show that, apart from being a source of important nutrients such as proteins, Bolivian Isaño is a source of antioxidants and has a higher concentration of flavonoids and anthocyanidins, particularly in the purple cultivar. Additionally, we identified the presence of three carotenoids in this food for the first time: Lutein, Neoxanthin, and β-carotene. Through these types of studies, we aim to revalue this food, which is little known both in Bolivia and outside the Andean region of South America. Considering its nutritional properties, we seek to increase its consumption.