Anti-Cancer and Antibacterial Effects of Terfezia boudieri-Derived Silver Nanoparticles

Background: The use of nanoparticles has markedly increased in biomedical sciences. The silver nanoparticles (AgNPs) have been investigated for their applicability to deliver chemotherapeutic agents in cancer treatment. However, the existing chemical and physical methods of synthesizing AgNPs are considered inefficient and expensive, and are fraught with toxicity. Objective: Natural products have emerged as viable candidates for nanoparticle production, including the use of Terfezia boudieri (T. boudieri), a member of the edible truffle family. Accordingly, our goal was to synthesize AgNPs using the aqueous extract of T. boudieri (green synthesized AgNPs). Since certain infectious agents are linked to cancer, we further investigated their potential as anti-cancer and antibacterial agents. Methods: The physico-chemical properties of green synthesized AgNPs were analyzed by UV-Vis, FT-IR, XRD, SEM and TEM. In addition, their potential to inhibit cancer cell (MCF-7 and AGS) proliferation as well as the growth of infectious bacteria were investigated. Synthesis of AgNPs was confirmed by the presence of an absorption peak at 450nm by spectroscopy. Results: The size of nanoparticles ranged between 20-30nm and exerted significant cytotoxicity and bactericidal effects in a concentration and time dependent manner compared to T. boudieri extract alone. Interestingly, synthesis of smaller AgNPs correlated with longer synthesis time and enhanced cytotoxic and bactericidal properties. Conclusion: This study shows that synthesis of smaller AgNPs correlated with longer synthesis time and enhanced cytotoxic and anti-bacterial effects.

Agrobacterium tumefaciens-Mediated Genetic Transformation of the Ect-endomycorrhizal Fungus Terfezia boudieri

Mycorrhizal desert truffles such as Terfezia boudieri, Tirmania nivea, and Terfezia claveryi, form mycorrhizal associations with plants of the Cistaceae family. These valued truffles are still collected from the wild and not cultivated under intensive farming due to the lack of basic knowledge about their biology at all levels. Recently, several genomes of desert truffles have been decoded, enabling researchers to attempt genetic manipulations to enable cultivation. To execute such manipulations, the development of molecular tools for genes transformation into truffles is needed. We developed an Agrobacterium tumefaciens-mediated genetic transformation system in T. boudieri. This system was optimized for the developmental stage of the mycelia explants, bacterial optical density, infection and co-cultivation durations, and concentrations of the selection antibiotics. The pFPL-Rh plasmid harboring hph gene conferring hygromycin resistance as a selection marker and the red fluorescent protein gene were used as visual reporters. The optimal conditions were incubation with 200 μM of acetosyringone, attaining a bacterial optical density of 0.3 OD600; transfer time of 45 min; and co-cultivation for 3 days. This is the first report on a transformation system for T. boudieri, and the proposed protocol can be adapted for the transformation of other important desert truffles as well as ectomycorrhizal species.