Silver nanoparticles production by two soil isolated bacteria, Bacillus thuringiensis and Enterobacter cloacae, and assessment of their cytotoxicity and wound healing effect in rats

Abstract

Production of silver nanoparticles by Bacillus thuringiensis and Enterobacter cloacae was performed and confirmed through UV-visible spectrophotometry, transmission electron microscopy (TEM), and x-ray diffraction (XRD) analyses. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay using mouse fibroblast cell line NIH-3T3 D4 was carried out and IC of AgNPs were obtained. The nontoxic dose of each AgNPs solution was selected for wound healing assay. Thirty-two rats were divided into four groups; two were used as the controls and two were treated by AgNPs that were produced by two bacterial strains. Results revealed that the produced AgNPs were amorphous, spherical in shapes, and had sizes under 100 nm. Histological analysis showed that AgNPs had better wound healing efficacy than the control groups. In conclusion, when the biologically produced AgNPs were used in vivo, they induced the epithelization, formation of the collagen bundles and fibroplasia and reduced the duration of completion of the epithelization and the angiogenesis.

Wound healing property of a gel prepared by the combination ofPseudomonas aeruginosaalginate andAlhagi maurorumaqueous extract in rats

“…The tested substances were first sterilized using the tyndallization method as microbial contaminations can interfere with the results of the MTT test. The tyndallization method is easy, safe, and free of adverse effects on the tested materials (Pourali et al, ).…”

“…Finally, the optical densities (ODs) of the wells were measured at 570 nm using enzyme‐linked immunosorbent assay reader. This assay was repeated three times and the IC 50 of each sample was calculated based on the following formula (Pourali et al, ; Pourali, Razavian Zadeh, & Yahyaei, ):…”

“…In order for these test subjects to adapt, they were kept in different cages at 25°C in a cycle of 12 hr light and 12 hr darkness. Food and water were given ad libitum before and throughout the whole experiment procedure (Pourali et al, ). For wound preparation, the rats were anesthetized using light ether (Sigma Aldrich, USA) and by the use of a sterilized circular blade one full‐thickness wound (8 mm in diameter) on the dorsal body surface of each rat was made, after shaving and sanitizing their skins (Pourali & Yahyaei, ).…”

“…The obtained results were analyzed using one‐way analysis of variance ( anova ) using SPSS software version 22, and the value of p < .05 was used as the cutoff for significance (Pourali et al, ).…”

Nanomaterials in the Context of Type 2 Immune Responses—Fears and Potentials

“…By analyzing bacterial growth and cytokine profiles in wound sections, the authors demonstrated the antimicrobial and anti-inflammatory potential of Ag NPs. Microbially synthesized Ag NPs enhanced wound-healing efficiacy in rats (11, 27, 28). Using a transforming growth factor (TGF)-β receptor inhibitor, Li and coworkers proposed the activation of the TGF-β1/Smad signaling pathway as a mechanism of wound-healing enhancement by polyvinylalcohol/chitosan oligosaccharide Ag nanofibers (29).…”