Phytochemical Constituents and Biological Activity of Native Tirmania nivea and Terfezia canerienasis

Desert truffles are hypogeous macrofungi naturally distributed in Middle Eastern and African deserts, growing without human intervention and renowned for their therapeutic value. The present study characterized Tirmania nivea and Terfezia canerienasis collected from the Western Egyptian Desert, assessing the active component and evaluated the antibacterial activity of their ethyl acetate extracts against Gram-positive (Staphylococcus sciuri MH491952.1, Staphylococcus aureus ATCC 6538) and Gram-negative (Pseudomonas aeruginosa Kasamber5) bacteria. Both truffle extracts and reference antibiotics showed marked antibacterial effects, with S. sciuri being the most sensitive, followed by S. aureus and P. aeruginosa. Tobramycin, although primarily used for Gram-negative pathogens, exhibited activity against Gram-positive strains (36 and 35 mm for S. sciuri and S. aureus, respectively, 29 mm for P. aeruginosa). The chromatographic bands separated by TLC were evaluated for their antibacterial activity using TLC-bioautography. Retention factor (Rf) values of Tirmania nivea were (0.60, 0.90, and 0.95), while Terfezia canerienasis showed Rf values at (0.54, 0.88, and 0.91) under a UV transilluminator at 225 nm and 366 nm. GC-MS analysis of volatile and non-volatile constituents explained that truffles differ in some phytochemical constituents and shared some compounds such as gallic acid, hexanal, furyl hydroxymethyl ketone, and dodecamethylcyclohexasiloxane known for antimicrobial, anti-inflammatory, and antioxidant effects. These findings highlight desert truffles as promising natural sources of bioactive compounds with therapeutic potential and applications in food, plant, and nosocomial infection control