Evaluating the antibacterial effect of synthesized herbal toothpastes and their efficacy for dentine tubule occlusion: Scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis.

The tubule occlusion of two newly developed herbal toothpastes was examined. They were prepared based on the mixture of pomegranate peel and Equisetum arvense extracts with strontium acetate. The antimicrobial activity of pomegranate peel and E. arvense were determined using minimum inhibitory concentration (MIC). Then, 30 mid-coronal dentin discs from the human third molars were etched for 30 s with the lemon juice (pH = 2.4). The specimens divided into the three groups. While the control group had 6 specimens, Groups 1 and 2 were including 12 specimens. Group 1 brushed with toothpaste containing 10% strontium acetate and 5% hydroalcoholic extracts of pomegranate peel, and Group 2 brushed with 5% strontium acetate, 5% hydroalcoholic extracts of E. arvense, and 5% hydroalcoholic extracts of pomegranate peel. Brushing was simulated for 6 months with 2 N loading. Then, 50% of discs in each group were immersed in lemon juice for 1 min. Moreover, specimens in control group were brushed with distilled water. Finally, all 30 discs were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDXS). The occluded dentin tubules were counted and statistically evaluated. It was found that the number of open dentin tubules decreases significantly after brushing with both tested toothpastes compared with control group (p < .001). Moreover, a significant difference was observed between two toothpastes before and after acid immersion process (p < .001). The SEM micrographs confirmed the dentin tubule occlusion of both herbal dentifrices. Besides, EDXS analysis approved the strontium and silica presence on the dentin tubules for the toothpaste which was based on E. arvense.

Novel Synergistic Activity of Quercus infectoria Gall Extract with Ceftazidime Against Standard and Multiple Drug Resistant Pseudomonas aeruginosa and Escherichia coli Isolates.

BACKGROUND: Multidrug resistance pathogens are important heath challenges. In this study, the antibacterial activity of 20 plant extracts was tested against standard as well as 20 multidrug-resistant (MDR) strains of Pseudomonas aeruginosa and Escherichia coli. The most active plant extract (Quercus infectoria) was selected for the synergistic activity assay. METHODS: Plant extracts were prepared by maceration using water, methanol and ethanol. The antibacterial activity of extracts was determined by both broth and agar dilution methods. The synergistic activity of QIG with ceftazidime (CAZ) was evaluated by checker board assay. Antioxidant activity was determined by colorimetric Ferric reducing antioxidant power (FRAP) assay. RESULTS: Only the methanol extract of QIG inhibited the growth of all the bacterial strains at a concentration of 1000 µg/mL. Other active extracts were Myrtus communis and Eucalyptusglobulus inhibiting the growth of most bacterial strains tested at 2000 µg/ mL. In checker board assay, the minimum inhibitory concentration (MIC) to both QIG extract and CAZ was reduced. The MIC of CAZ was reduced from 64-4096 µg/mL to 4 µg/mL for P. aeruginosa and to 16 µg/mL for E. coli isolates. CONCLUSION: The QIG extract exhibited potent antioxidant activity determined by FRAP assay. The result of this study showed a strong synergistic activity between QIC and CAZ on P. aeruginosa and E. coli. The activity within ethyl acetate-methanol (7:3) fraction indicates that the active components of the plant have a semi-polar nature and further work with this fraction may lead to understanding the mechanism of this synergistic activity.

Biocompatible electrospinning chitosan nanofibers: A novel delivery system with superior local cancer therapy.

In this study, an electrospinning technique was used for the fabrication of novel biomedicated nanofibers which are applied for preventing wound infections and local chemotherapy. CURs containing nanofibers with a crosslinking agent (Si-O-Si network) have been produced through functionalization of graphene oxide with APTES. In vitro drug release profile results showed the novel nanofibers could limit the drug's initial burst release and provide better sustainability in comparison with the blend nanofibers without modified GO. The novel delivery vehicle can inhibit the growth of MRSA and S. epidermidis up to 94% and 88%. Also in vitro cell toxicity experiments which were performed by XTT method on MCF-7, HEP G2 and L929 cell lines showed that anticancer activity of CUR remained intact even after loading into nanofibers. This result suggested that the fGO-Si-CUR including nanofibers were a promising candidate for postoperative chemotherapy.