Fig Leaf Bioactivity and Safety: Temperature Optimization and FTIR Authentication

Area of Science:

• Agricultural Science
• Food Science
• Biochemistry

Background:

• Fig (Ficus carica L.) leaves are an underutilized agricultural byproduct with potential as a functional food ingredient.
• Consumer interest in functional foods is increasing, highlighting the need to explore novel sources.

Purpose of the Study:

• To investigate the effects of drying temperature on the bioactivity and safety of water extracts from four fig leaf cultivars.
• To assess the potential of fig leaf extracts as functional food ingredients and explore their selective anti-cancer properties.

Main Methods:

• Four fig leaf cultivars (BTM, Black Violet, Longue d'Aout, Sultane) were dried at temperatures ranging from 50°C to 80°C.
• Water extracts were analyzed for total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity (DPPH, ABTS, FRAP).
• Fourier-transform infrared (FTIR) spectroscopy with principal component analysis (PCA) was used for cultivar discrimination. Safety was evaluated using MTT assays on Caco-2, HepG2, and THLE-2 cells.

Main Results:

• Optimal drying temperature for bioactivity was 60°C across all cultivars (p < 0.05).
• Longue d'Aout cultivar showed superior bioactivity (TPC = 53.8 mg GAE/g, DPPH IC50 = 0.96 mg/mL).
• Higher temperatures (70°C-80°C) reduced bioactivity, while FTIR-PCA achieved 96.8% cultivar discrimination accuracy. Extracts demonstrated excellent safety (IC50 = 7-15.3 mg/mL) and selective cytotoxicity against HepG2 cancer cells (2.18-fold selectivity).

Conclusions:

• Fig leaf extracts possess significant bioactivity and excellent safety profiles, validating their use as functional food ingredients.
• The optimal drying temperature of 60°C preserves bioactivity, and FTIR-PCA is effective for quality control.
• Fig leaf extracts exhibit selective toxicity towards cancer cells, warranting further investigation into their anti-cancer mechanisms.