Fusarium verticillioides (Sacc.) Nirenberg is among the most common Fusarium species corn pathogens worldwide, and has been recognized as a fumonisin B 1 (FB 1 ) and fumonisin B 2 (FB 2 ) producer. In the present work, extracts of 58 F. verticillioides isolates from corn samples collected from Sohag Governorate, Egypt, were tested for their biotoxicity and production of fumonisin toxins. Forty-four Fusarium verticillioides isolates out of 58 tested produced FB 1 or FB 1 and FB 2 (15 and 29 isolates, respectively) on potato-sucrose agar medium, detected by TLC, whereas the other 14 isolates did not produce fumonisin toxins. HPLC crude extract analysis confirmed the results from TLC plates. Brine shrimp larvae as well as the Gram-negative bacteria Pseudomonas aeuroginosa showed low bio-sensitivity towards the F. verticillioides crude extract toxicity, whereas the Gram-positive bacteria Bacillus cereus and Bacillus subtilis, especially B. subtilis, showed higher sensitivity towards the tested Fusarium crude extracts. These results enabled us to bio-evaluate and chemically detect fumonisin mycotoxins using a simple agar medium technique.

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Silver nanoparticles (AgNPs) production with antibacterial and antitumor properties is an important application in the medical field. This study introduces a novel organism that can be used for the large-scale production of AgNPs. The edible brown alga Eisenia bicyclis was used as a reducing agent to biosynthesize stable AgNPs. In this study, we achieved producing 50 mg AgNPs using only 1 g dried E. bicyclis seaweed. The optimized conditions for AgNPs biosynthesis were performed at a reaction temperature of 90°C, a seaweed extract concentration of 0.4%, and AgNO3 concentration of 0.5 mM within 20 minutes the results showed that the formed nanoparticles are spherical and monodispersed with average size 18.5 ± 1.2 nm. The antibacterial activity of biosynthesized AgNPs was evaluated against some human clinical pathogens. Results showed that AgNPs had antibacterial activity against all tested bacterial strains, with the appearance of a clear zone equal to or larger than positive controls. Also, there was a concentration-dependent growth inhibition of in vitro cultured breast cancer cells treated with AgNPs and overexpression of p53, Bax, and underexpression of Bcl-2. Silver nanoparticles synthesized by this method provide a potential source for antibacterial and anti-cancer applications.

T HE USE of computational methods for constructing a protein model to support experimental findings aid in answering a great number of questions about the mechanisms underlying various scientific processes. Constructing a protein model and molecular docking computationally can present a clear explanation of biological process integrating to experimental findings. One of the most precise methods currently available is detecting a homolog to a specific amino acid sequence to use it as a template for modeling. In this paper, we present synthesis of 13.6 ± 2.2nm silver nanoparticles using extracellular filtrate of Aspergillus oryzae and homology modeling of five targeted extracellular proteins, as well as homology prediction for each protein's active site. In addition, a nanoparticle of silver that docks with all five proteins is evaluated in silico. According to the results, only 32 out of 50 top 10 solutions for each protein contained polar oxygen or nitrogen atom neighbors. Seven of the 50 solutions for FAD-dependent oxidoreductase contained the greatest number of detectable polar neighbors (six measurements). This finding supports the hypothesis that extracellular fungal proteins play a crucial role in capping silver nanoparticles at various positions and preventing aggregation and sedimentation of nanoparticles. Through homology modeling and docking, we reveal the interaction between FAD-dependent oxidoreductase and silver nanoparticles for the first time.