Chemical Composition, Antioxidant, and Antimicrobial Activities of Bark and Wood Extracts from Taxodium distichum L.

The chemical composition and bioactivities were studied for hydroethanolic extracts from Taxodium distichum L. bark (TDB) and wood (TDW) samples harvested in Ramsar, Northern Iran. The TDW extract showed higher antioxidant activity (30.7%) compared to the TDB extract (10.5%) at the same concentration (1000 µg/mL), indicating a richer redox-active profile in wood tissues. The TDB extracts exhibited higher efficacy in antimicrobial tests, with minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) values against Staphylococcus aureus of 500 and 1000 µg/mL, respectively. Surprisingly, the MIC and minimum fungicidal concentration (MFC) of TDB extract against Candida albicans were 7.81 and 31.2 µg/mL, respectively. The TDW extract had no antibacterial activity but showed fungicidal activity at 7.81 µg/mL against C. albicans. These differences indicate that the TDB extract is more potent against microbial pathogens, while the TDW extract offers superior antioxidant potential. Gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of 22,23-dihydro-stigmasterol (15.9%) in TDB extract and γ-sitosterol (15.3%) in TDW extract as the major compounds. The combined findings underscore the therapeutic relevance of T. distichum bark and wood extracts as natural sources of bioactive compounds with possible applications in antimicrobial and antioxidant formulations for pharmaceutical, food, and cosmetic industries.