Phenolic Composition and Bioactivities of Invasive Ailanthus altissima (Mill.) Swingle Leaf Extracts Obtained by...

Area of Science:

• Phytochemistry
• Natural Product Chemistry
• Pharmacognosy

Background:

• Ailanthus altissima, an invasive species, possesses bioactive compounds with significant practical potential.
• Extraction of these compounds is crucial for exploring their applications.

Purpose of the Study:

• To investigate the sequential extraction of antioxidant compounds from Ailanthus altissima leaves using n-hexane and ethanol.
• To evaluate the influence of harvesting season, processing methods (freezing vs. drying), and solvents on compound yield and antioxidant activity.

Main Methods:

• Sequential extraction using n-hexane and ethanol solvents.
• Scanning electron microscopy for microstructure analysis.
• CIELAB color space analysis.
• High-performance liquid chromatography (HPLC) for phenolic profiling.
• Ferric-reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assays for antioxidant activity assessment.
• Antibacterial activity testing against Staphylococcus aureus and Enterococcus faecalis.

Main Results:

• Ethanol is highly efficient for extracting phenolics, flavonoids, tannins, and carotenoids.
• Dried leaves harvested in autumn showed higher phenolic content (nine polyphenols) compared to frozen leaves (five to six polyphenols).
• Dried leaves exhibited better antibacterial activity, particularly against Staphylococcus aureus and Enterococcus faecalis.

Conclusions:

• Ailanthus altissima leaves are a valuable source of bioactive compounds, especially when extracted with ethanol.
• Processing methods and harvesting season significantly impact the phytochemical profile and bioactivity.
• The high bioactive content and demonstrated activities suggest A. altissima leaves are suitable for natural raw material applications.