Medical and Cosmetic Applications of Fungal Nanotechnology: Production, Characterization, and Bioactivity

Evaluation the effect of ZnO nanoparticle derived Bacillus subtilis on the expression of efflux pump genes (AdeB AdeRS) in Acinetobacter baumannii

PURPOSE

Green approach to the nanoparticles, including metal oxides due to inevitable disadvantages of physical or chemical synthesis routes is attractive nowadays. Zink oxide (ZnO) nanoparticles play a key role in the medical and pharmaceutical fields. This research aimed to study the biologically synthesized ZnO nanoparticle using Bacillus subtilis, and evaluated its antibacterial properties.

METHODS

Bacillus subtilis culture in a broth nutrient environment was used, followed by adding the Zinc acetate dehydrate. Biosynthesis of the nanoparticles was confirmed by the XRD, FTIR, and SEM imaging. The antibacterial effects of NPs on the expression of AdeB efflux pump genes and the AdeRS regulator were studied; clinical species of the Acinetobacter baumannii were collected from clinical samples of Khorramabad, using the phenotypic (MIC) and the genotypic methods through real-time PCR.

RESULTS

X-ray diffraction pattern (XRD) result showed, that all of the peaks were related to the ZnO, and no other peaks were detected; it also demonstrated nanostructure nature with crystallite size of 25-50 nm. The results indicated, that the antibacterial properties of the nanoparticle increased the AdeRS expression and decreased the AdeB expression in 40% of the A. Baumannii. In addition, there was an increase in the AdeB expression in 60% of the species, indicating an increased probability for mutation.

CONCLUSION

Given the desirable inhibitory effects of biosynthesized ZnO NPs on the expression of AdeB and AdeRS, which play an important role in the pharmaceutical resistance of Acinetobacter species, it seems that ZnO NPs can be used as a medication candidate in pharmaceutical industry in the future.

Are Fungal Endophytes Merely Mycorrhizal Copycats? The Role of Fungal Endophytes in the Adaptation of Plants to Metal Toxicity

The contamination of soil with toxic metals is a worldwide problem, resulting in the disruption of plant vegetation and subsequent crop production. Thus, remediation techniques for contaminated soil and water remain a constant interest of researchers. Phytoremediation, which utilizes plants to remove or stabilize contaminants, is perceived to be a promising strategy. However, phytoremediation's use to date is limited because of constraints associated with such factors as slow plant growth rates or metal toxicity. Microbial-assisted phytoremediation serves as an alternative solution, since the impact of the microbial symbionts on plant growth and stress tolerance has frequently been described. Endophytic fungi occur in almost every plant in the natural environment and contribute to plant growth and tolerance to environmental stress conditions. Although this group of symbiotic fungi was found to form association with a wide range of hosts, including the non-mycorrhizal Brassicaceae metallophytes, their role in the response of plants to metal toxicity has not been thoroughly elucidated to date. This review summarizes the current knowledge regarding the role of endophytic fungi in the tolerance of plants to toxic metals and highlights the similarities and differences between this group of symbiotic fungi and mycorrhizal associations in terms of the survival of the plant during heavy metal stress.