Native carotenoid profile of banana inflorescence from Madeira Island

Banana inflorescence, often discarded, is increasingly used in vegan cuisine, but its carotenoid composition, including provitamin A and lutein, and its bioavailability are still underexplored. In this study, the native carotenoid profile of banana inflorescence (Musa acuminata) from Madeira Island was assessed, with the plant material being lyophilized to obtain a homogeneous powdered sample. Carotenoids were exhaustively extracted with organic solvents and both the saponified and non-saponified extracts were analysed by HPLC-DAD. Co-chromatography with an oleoresin of marigold petals (Tagetes sp.), an established source of carotenoid esters already characterised by HPLC-DAD-(APCI+)MS/MS, was also performed for comparison purposes. Twenty-six carotenoids were separated in the non-saponified extract. The major carotenoids found were the provitamin A carotenes (all-E)-b-carotene (42%), (all-E)-a-carotene (17%), and (9Z)-b-carotene (6%) and the other free xanthophyll class (all-E)-lutein (14%). Eleven carotenoid esters were identified, including seven lutein diesters and three monoesters of the provitamin A (all-E)-b-cryptoxanthin. The diester (all-E)-lutein-3’-O-myristate-3-O-palmitate was the main xanthophyll ester found in the sample of banana inflorescence, presenting the same chromatographic and spectroscopic characteristics of the peak identified in marigold extract. The absence of these ester peaks accompanied by the increased proportion of both free lutein and b-cryptoxanthin in the saponified extract of carotenoids of this sample also confirmed the presence of acylated carotenoids. In summary, the inflorescence of banana plants from Madeira Island was shown to be a distinctive source of provitamin A carotenoids and lutein, free and esterified. For vegetarians and vegans who do not consume animal-derived foods with pre-formed vitamin A, provitamin A carotenoids are the main source of this essential nutrient. Therefore, banana inflorescence can be an effective nutritional strategy and a promising alternative for processed functional foods.