STUDY OF THE BIOACTIVE COMPOUND COMPOSITION, ANTIMICROBIAL, AND CYTOTOXIC ACTIVITIES OF ENDEMIC PLANT SPECIES OF ADJARA-LAZETI.

The flora of Adjara (Southern Colchis) is characterized by high biodiversity, a significant proportion of endemism, and unique forest ecosystems. Our study aimed to analyze the biologically active compounds in leaves of five Adjara-Lazeti endemic species: Astragalus sommieri, Quercus petraea subsp. Dshorochensis, Amaracus rotundifolius, Rhododendron smirnovii, and Rhododendron ungernii. Methanolic leaf extracts were prepared and analyzed using GC-MS to identify bioactive constituents. Antimicrobial (specifically fungicidal) activity was evaluated in vitro against Colletotrichum gloeosporioides, Alternaria alternata, and Fusarium solani using the agar well diffusion method. Cytotoxicity was assessed on human lung carcinoma (A-549) and normal skin fibroblasts (WS-1) using resazurin and Hoechst assays. For GC-MS analysis and cytotoxicity assays, methanolic extracts were prepared, the aqueous and 40% ethanolic extracts were used exclusively for antifungal activity evaluation. GC-MS analyses revealed a diverse array of bioactive compounds, including phenolic acids, flavonoids, terpenoids, sterols, etc. Rhododendron ungernii extract exhibited the highest selective cytotoxicity against A-549 cells (IC₅₀=12.4±0.5 µg/ml; SI=9.68). Strong antifungal activity was observed in R. ungernii, Astragalus sommieri, and R. smirnovii extracts. These results suggest the potential of these endemic species as sources of selective anticancer and antimicrobial agents. All experiments were performed in triplicate. Results are expressed as mean±standard deviation (SD). Statistical analysis was carried out using one-way analysis of variance (ANOVA). Differences were considered statistically significant at p<0.05.