Title : Screening antifungal potential in the genus Piper: Analytic Hierarchy Process (AHP) selection and phytochemical profiling of active fractions in Piper lanceifolium
Abstract:
The high chemical diversity of the genus Piper offers considerable opportunities for the discovery of antifungal compounds with potential agricultural applications. However, the large number of species and extracts available for evaluation makes the identification of the most promising candidates a major challenge in plant bioprospecting. This is particularly relevant for passion fruit crops, including sweet granadilla (Passi?ora ligularis), gulupa (P. edulis f. edulis), and yellow passion fruit (P. edulis f. ?avicarpa), whose productivity and fruit quality are frequently affected by fungal diseases caused by species of Fusarium, Colletotrichum, Cladosporium, and Botrytis. The limitations associated with intensive synthetic fungicide use further support the search for more sustainable phytosanitary alternatives. Accordingly, this study integrated antifungal screening, metabolomic profiling, multivariate statistics, multicriteria decision analysis, and bioassay-guided phytochemistry to prioritize Piper species with potential for the management of phytopathogens associated with Passi?ora crops. A total of 79 ethanolic extracts obtained from 65 Piper species were screened against four fungal phytopathogens using agar-based mycelial growth inhibition assays. The extracts were chemically profiled by LC-ESI-qTOF-MS, and metabolic and bioactivity datasets were integrated through supervised multivariate analyses, including OPLS-DA and S-plots. This strategy enabled the prioritization of 17 species for concentration–response assays and determination of half-maximal inhibitory concentrations (IC??). An Analytic Hierarchy Process (AHP), incorporating metabolomic, statistical, and antifungal activity criteria, was subsequently applied to rank the most promising candidates. Several species achieved high multicriteria scores, and Piper lanceifolium was selected for further phytochemical investigation based on its favorable biological and chemical profile, together with the limited information available on its secondary metabolism. The ethanolic leaf extract of P. lanceifolium was fractionated by vacuum liquid chromatography into dichloromethane, ethyl acetate, isopropanol, and ethanol–water fractions. Among them, the dichloromethane fraction showed the strongest antifungal response, with mycelial growth inhibition exceeding 94% against all four evaluated phytopathogens. Based on this activity, the dichloromethane fraction was selected for successive flash chromatographic separations, resulting in the isolation of five specialized metabolites belonging to different structural classes, including benzoic acid derivatives, a phenylpropanoid, a chroman, and a flavonoid. Their structures were established by NMR spectroscopy and comparison with reported spectroscopic data. Biological evaluation of the isolated compounds is currently underway to identify the metabolites primarily responsible for the antifungal activity observed in the dichloromethane fraction. Overall, this study demonstrates the value of integrating metabolomics and multicriteria decision-making with bioassay-guided phytochemistry to improve the efficiency of plant bioprospecting and supports P. lanceifolium as a promising source of antifungal metabolites for sustainable crop protection. This study was funded by the Sistema General de Regalías of Colombia under project BPIN 2023000100058. Research activities on Colombian biodiversity were conducted under Genetic Resource Access Contract No. 121 of January 22, 2016, and its Amendment (Otrosí) No. 21, executed between the Ministerio de Ambiente y Desarrollo Sostenible and the Universidad Nacional de Colombia.
