Flavone-rich Passiflora edulis fruit shells as urease inhibitors for sustainable agricultural solutions

Qualitative and quantitative methods were used to demonstrate how plant development stages impact flavonoid C-glycoside and tannin accumulation in Passiflora edulis (Passifloraceae). Distinct parts from juvenile to mature plants were analyzed. Thin-layer chromatography (TLC) and ultra-high performance liquid chromatography (UHPLC) were used to quantify flavonoids as vitexin and tannins as epicatechin, with total flavonoids assessed following the Brazilian Pharmacopoeia method. Ethanolic extracts were tested for urease inhibition. Leaf and fruit shell extracts shared similar flavonoid profiles containing apigenin, chrysin, and luteolin glycosides. Leaves consistently exhibited the highest flavonoid concentration (3.5% dry extract), with 3.6-fold more flavone glycosides than fruit shell extracts. Roots had the highest tannin concentration. Leaf and fruit shell extracts from flowering II plants inhibited urease by 57%. This underscores the significance of flavone C-glycosides as urease inhibitors. The study demonstrates the effective inhibition of ureases by P. edulis fruit shells, highlighting their significant potential for agricultural applications through waste valorization strategies.