Metabolomic characterization and multi-target biological activities of Saponaria pumila and Suaeda confusa: integrating in vitro and in silico approaches

Abstract

In the present study, several extracts (ethyl acetate, methanol, and water) of Saponaria pumila and Suaeda confusa were used to characterize and identify their biological activities. The chemical characterization was performed using HPLC-ESI-Orbitrap-MS/MS. The total phenolic and flavonoid contents were determined by the Folin assay and AlCl3 assay, respectively. The antioxidant capacity of the extracts was determined by DPPH, ABTS, CUPRAC, FRAP, MCA, and PBD assays. The enzyme inhibitory activity of the tested extracts was examined against several enzymes, namely, cholinesterase (AChE and BChE), tyrosinase, and carbohydrate digestive enzymes (α-amylase and α-glucosidase). Among the tested extracts of both plants, the S. pumila MeOH extracts exhibited the highest total phenolic and flavonoid contents, measuring 44.82 mg GAE per g and 72.60 mg RE per g, respectively. The lowest values, 12.30 mg GAE per g and 8.33 mg RE per g, respectively, were recorded by the S. confusa water extract. The antioxidant capacity of the S. pumila extracts in radical scavenging and reducing power assays was in the order of methanol (MeOH) > water > ethyl acetate (EA) extract. In the case of the plant species S. confusa, the MeOH extracts again yielded the highest value, with the same pattern as in S. pumila. Water extracts comparatively showed the highest ABTS scavenging activity, with a value of 75.70 mg TE per g. The water extract of S. pumila exhibited the strongest inhibitory effect against AChE (2.00 mg GALAE per g) and tyrosinase (42.47 mg KAE per g), while its EA extract gave the highest BChE inhibitory activity (1.87 mg GALAE per g). The MeOH extracts of S. confusa exhibited the highest inhibition of AChE (2.59 mg GALAE per g) and tyrosinase (46.28 mg KAE per g). The EA extract of S. pumila showed no anti-AChE activity, while all extracts of S. confusa showed no activity against α-glucosidase. The antimicrobial activity of the extracts was screened, revealing species- and solvent-dependent activities. The highest susceptibility was observed against Listeria monocytogenes and Aspergillus fumigatus (MICs of 0.25–0.5 mg mL−1), while Pseudomonas aeruginosa showed notable resistance. The extracts of S. pumila and S. confusa possess strong antioxidant potential, along with promising neuroprotective and dermoprotective properties, warranting further investigation in future studies.