Bendrihem Khadra Afaf2026-04-262026-04-262024576-001-PHDhttp://dspace.univ-khenchela.dz:4000/handle/123456789/10881Salvia balansae, an endemic perennial plant native to Algeria, particularly in the Mostaganem and Aures regions, exhibits significant medicinal potential. This study aims to explore the chemical composition and biological activities of Salvia balansae extracts obtained from different plant organs (leaves, flowers, and stems) collected from the Aures Mountains using various solvents (ethanol, methanol, and acetone). The maceration technique was employed to extract the chemical constituents, and the extracts were analysed for their total phenolic compounds, flavonoids, flavonols, condensed and hydrolysable tannin, triterpenoid, and ortho-diphenols content using the microplate reader technique. Advanced analytical techniques, such as liquid chromatography coupled with mass spectrometry (LC-MS), were used to identify the specific phenolic compounds. The antioxidant activity of the extracts was assessed through multiple in vitro assays, including DPPH, ABTS, FIC, FRAP, Phenanthroline, CUPRAC, SNPAC, and Superoxide radical scavenging activity by alkaline DMSO assay. Additionally, the photoprotective properties were evaluated, given the increasing interest in natural sunscreen formulations. Principal Component Analysis (PCA) and Unweighted Pair-Group Method with Arithmetic Mean (UPGMA) were applied to discern the similarities and differences among the extracts concerning their chemical composition, secondary metabolite content, and biological activities. Furthermore, the anti-inflammatory activity of the extracts was evaluated using the Bovine Serum Albumin (BSA) method, and the antidiabetic potential was assessed through the alpha-amylase inhibition assay. Results revealed that S. balansae extracts exhibit significant antioxidant, photoprotective, anti-inflammatory, and antidiabetic activities. This is attributed to their rich phenolic content. Moreover, the study identified several key phenolic compounds and demonstrated the impact of solvent type and plant organ on the efficacy of the extracts. This research represents the first comprehensive investigation into the phytochemical and biological properties of Salvia balansae from the Aures Mountains, highlighting its potential as a source of natural antioxidants, photoprotective agents, anti-inflammatory, and antidiabetic agentsenOther