Integrated metabolomics and network pharmacology to explore the mechanisms for the antioxidant activity of Passiflora edulis peels

Fruit waste-derived substances, particularly from Passiflora edulis (passion fruit) peels, have long been recognized as promising sources of bioactive compounds with therapeutic potential. This plant is typically grown in Malaysia in both purple and yellow varieties. It is a perennial vine with a distinct flavour and scent that grows well in locations that suit it. The phytochemicals of P. edulis exhibit a range of pharmacological effects, notably antioxidant properties, highlighting the value of P. edulis peels as a functional food. In this study, the antioxidant capacity of P. edulis peel extracts was assessed using the DPPH assay. Peels dried at room temperature significantly inhibited free radical DPPH by81.20 %. The phytochemical content was quantified through Total Phenolic Content (TPC) and Total Flavonoid Content (TFC) analyses, which showed that peels dried at room temperature contains high TPC and TFC values, 23.71 ± 3.86 GAE/g and 35.43 ± 0.10 QE/g, respectively. The results from LCMS-QTOF found that the extract contains 18 potential major compounds including oleamide, 6E,9E-octadecadienoic acid, C16 Sphinganine, dodecanamide, and 2-hexyl-decanoic acid. Swiss Target Prediction was employed to identify potential molecular targets, while oxidative stress-related targets were retrieved from the DrugBank, GeneCards, and DisGENET databases. A component–target-pathway network was constructed, encompassing 12 bioactive compounds after initial ADMET screening and 10 target genes. Key hub genes identified included TP53, AKT1, CASP3, BCL2, STAT3, HSP90AA1, HSP90AB1, BCL2L1, ESR1, and MDM2. The implicated antioxidant-related pathways involved intrinsic apoptotic signaling, mitochondrial membrane organization, and mitochondrial transport, among others. These findings reinforce the potential of P. edulis peels as a valuable antioxidant-rich functional food for disease prevention and health promotion.