GC-MS Profiling, Phenolic and Flavonoid Contents, Exploratory Cytotoxicity in MCF-7 Cells and Surrogate Anthelmintic Screening of Zygophyllum propinquum Methanolic Extract

Abstract

Background: Medicinal plants are important sources of structurally diverse secondary metabolites with potential biological activities. Zygophyllum propinquum is a halophytic medicinal plant whose phytochemical composition and biological properties remain insufficiently characterized. This study investigated the phytochemical profile of its methanolic leaf extract and evaluated its effects on MCF-7 cell viability and in a preliminary free-living annelid surrogate screening model. Methods: Phytochemical constituents of the methanolic extract of Z. propinquum were profiled by gas chromatography-mass spectrometry (GC-MS). Total phenolic content (TPC) and total flavonoid content (TFC) were determined spectrophotometrically in triplicate (n = 3) and expressed as mg gallic acid equivalents (GAE)/g dry extract and mg quercetin equivalents (QE)/g dry extract, respectively. MCF-7 human breast adenocarcinoma cells were exposed to 15.6-1000 µg/mL extract for 24 h and cell viability was evaluated using the MTT assay (n = 3). Preliminary worm-paralysis and mortality screening was performed using the free-living annelid Eisenia fetida, with five worms together in a single 20 mL vessel per treatment condition; ZPPE was tested at 100 and 200 mg/mL. Mebendazole (10 mg/mL) and distilled water were used as positive and negative controls, respectively. Results are presented as mean±SD where applicable. For the worm assay, each treatment condition comprised five worms exposed together in a single 20 mL vessel. Paralysis and mortality times were therefore summarized descriptively at the worm level and kaplan-meier curves were used only for descriptive visualization; no inferential between-group P values were reported because independent treatment-vessel replication was not available. Result: Following conservative re-evaluation of the GC-MS profile, three non-silylated compounds were retained as tentative library-based assignments: n-undecane, methyl hexadecanoate and methyl stearate. Total phenolic and flavonoid contents were 1.98±0.07 mg GAE/g dry extract and 1.91±0.04 mg QE/g dry extract, respectively. MCF-7 cell viability decreased modestly with increasing extract concentration, reaching 71.40±3.00% at 1000 µg/mL. Because 50% viability was not reached within the tested concentration range, the IC50 was reported as greater than 1000 µg/mL. In the E. fetida surrogate assay, the 200 mg/mL extract produced shorter paralysis and mortality times than the 100 mg/mL extract; however, both extract concentrations acted more slowly than mebendazole.