محمدرضا فرهپور

Nanocomposites are prepared from various materials that may have antibacterial activity. This study aimed to investigate antibacterial and antifungal activityies of nanocomposites of bohemite-gold and bohemite-gold-chitosan by help of aqeous extract of peppermint.

In the current study, the nanocomposites were prepared by exextracellular biosynthesis and antibacterial properties were investigated by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and killing-time curve by classic method of consecutive dilutions by Clinical & Laboratory Standards Institute.

The results showed that MIC and MBC were 10 µg/mL and 20 µg/mL for bohemite group, respectively. The results also showed that MIC and MBC were 2.50 µg/mL and 5 µg/mL against Acinetobacter baumannii and 5 µg/mL and 10 µg/mL against Escherichia coli, respectively. The greatest antibacterial activity for of bohemite-gold and bohemite-gold-chitosan was observed for a period of 6 to 24 h. Based on ourfindings, bohemite showed lower antibacterial activity compared with bohemite-gold and bohemite-gold-chitosan against the mentioned bacteria.

The prepared nanocomposites did not show any antifungal activity. Thus, bohemite-gold and bohemite-gold-chitosan nanocomposites have antibacterial activities against bacteria inducing infection in wound.

Bacteria create biofilms as a mechanism to increase survival. The use of antibiotics to fight against them causes antibiotic resistance. Therefore, there is a need to produce strong anti- biofilm substances to fight biofilms. This experimental study was conducted with the aim of investigating the effects of malachite / zinc oxide / chitosan nanocomposites on the expression of pathogenic genes in Pseudomonas aeruginosa and Staphylococcus aureus.

Experimental, malachite, malachite / zinc oxide and malachite / zinc oxide / chitosan nanocomposites were prepared. The amount of biofilm formation of bacteria was checked with the help of crystal violet dye and TTC. The Minimum Biofilm Inhibitory Concentration and the Minimum Biofilm Eradication Concentration were investigated to measure the anti- biofilm activity of nanocomposites. The extent of cell survival in the vicinity of nanocomposites was evaluated by calcein-AM staining. The expression of rhlI and lasI genes in Pseudomonas aeruginosa and fnbA and fnbB genes in Staphylococcus aureus were investigated using Real- Time PCR technique. Data were analyzed using ANOVA test.

Based on the results of this study, the highest amount of anti- biofilm activity was observed in malachite / zinc oxide / chitosan, malachite / zinc oxide, and malachite nanocomposites, respectively. The results showed that the final malachite / zinc oxide / chitosan nanocomposite with a concentration of 7.81 μg/ml could inhibit the biofilm formation of two bacteria by about 50 ± 10% (MBIC50) and with a concentration of 15.62 μg/ml, the biofilm formed by both bacteria were remove about 50 ± 10% (MBEC50). Malachite / zinc oxide and malachite / zinc oxide / chitosan nanocomposites reduced the expression of rhlI and lasI genes of Pseudomonas aeruginosa and fnbA and fnbB genes of Staphylococcus aureus bacteria (P < 0.001). The use of malachite / zinc oxide / chitosan final nanocomposite reduced rhlI gene expression by 166.66 times, lasI gene expression by 30.30 times, fnbA expression by 20.70 times, and fnbB expression by 100 times compared to the control group (P < 0.001).

Malachite / zinc oxide and malachite / zinc oxide / chitosan nanocomposites probably have anti- biofilm activity on Pseudomonas aeruginosa and Staphylococcus aureus bacteria.

Diabetes is one of the most common glandular diseases. Delay in wound healing process is known as a major challenge in these patients. Fenugreek is known to have therapeutic effects. Thus, the present study was conducted to investigate the oral administration of fenugreek seed aqueous extract (FSE) on wound healing in the experimental animal model. An excisional model was created on 24 rats. Streptozotocin was administrated in order to induce the diabetes. A surgery was performed and a circular wound with a diameter of 6 mm was created on the dorsal surface of each rat. Animals were divided into 4 groups including non-diabetic, diabetic control and diabetic treated rats, with oral administration of different doses of FSE (200 and 400 mg/kg). The wound area, histological parameters, blood glucose and insulin levels were measured on days 3, 7 and 16. The results showed that the wound area and blood glucose were significantly decreased in FSE-treated animals in comparison with diabetic control from day 7 (P<0.05). It can be suggested to use oral fenugreek seed aqueous extract on improved the blood sugar and wound healing in diabetic rats.

The proliferation of antibiotic-resistant microorganisms in wounds has grown efforts to synthesis the antibacterial nanostructured compounds for overcoming on antibiotic-resistant microorganisms. The aim of the current study is to investigate the antibacterial and anti-fungal activities of laterite nanoparticles (Ltt-NPs), silver/laterite (Ag/Ltt-NCs) and silver/laterite/chitosan nanocomposites (Ag/Ltt/Chn-NCs) by analyzing minimum inhibitory concentration, minimum bactericidal concentration and killing-time of Candida albicans fungus and Acinetobacter baumannii, Streptococcus pyogenesis, Escherichia coli and Proteus mirabilis bacteria. We found that, where 5.0 µg/ml of Ag/Ltt-NCs are efficient against Acinetobacter baumannii and Streptococcus pyogenesis, 2.5 µg/ml of Ag/Ltt/Chn-NCs has a favorable efficiency against Escherichia coli and Proteus mirabilis. No significant difference was observed between the antibacterial activity of Ag/Ltt-NCs and Ag/Ltt/Chn-NCs (p=1.00). In addition, Ltt-NPs showed a poor antibacterial activity compared to the Ag/Ltt-NCs and Ag/Ltt/Chn-NCs. Moreover, we found that neither nanocomposite do not show antifungal activity. Our results show that the highest antibacterial activity of the nanocomposites occurs between 6-24 hours. In sum, the prepared nanocomposites show

Nanocomposites contain compounds that show beneficial antibiotic properties. The aim of this study was to investigate the antibacterial and antifungal effects of chitosan-functionalized aluminum oxide- titanium oxide nanocomposite on selected microorganisms. In this study, after preparation of aluminum oxide-titanium oxide-chitosan nanocomposite by extracellular biosynthesis method, their antibacterial properties were determined by determining the MIC, MBC and measuring the time of bacterial death. The National Committee for Laboratory Standards was determined and reported by the classical method of preparing consecutive dilutions. The results showed that the nanocomposite showed antibacterial activity at the highest concentrations of 10 and 20 μg / ml for Al2O3 group. While in concentrations (2.5-5 μg / ml) in TiO2 / Al2O3 and TiO2 / Al2O3 / Csn showed strong antibacterial activity against pathogens. It also showed that the highest antibacterial activity of TiO2 / Al2O3 and TiO2 / Al2O3 / Csn is from 6 to 24 hours. However, Al2O3 in all studies showed less antibacterial activity compared to TiO2 / Al2O3 and TiO2 / Al2O3 / Csn. The results of the study also showed that the nanocomposite has no antifungal activity. Aluminum oxide-titanium oxide-chitosan nanocomposites have antimicrobial effect on the studied bacteria.

The aim of the current study was to evaluate of wound healing activity of flaxseed oil and its combination with Cinnamon hydroalcoholic extract on excision of wound healing model in rabbit. Sixty New Zealand white rabbits were randomly allocated into 4 experimental groups. Two full-thickness skin excisional wounds were created on thoracolumbar region on each side of the dorsal midline in each rabbit. Rabbits in group 1 did not receive any treatments. In group 2, rabbits received placebo ointment; in group 3, animals were treated with flaxseed oil 2% ointment. In group 4, rabbits received ointment containing a combination of flaxseed 2%+Cinnamon hydroalcoholic extract 3%. Wound area (mm2) was determined on days 4, 8, 12, 16 and 20 using a transparent paper. Tissue samples were collected on days 3, 7, 14 and 20 for histopathological studies with Masson trichrome staining.
According to the results, ointment containing a combination of flaxseed oil 2%+Cinnamon hydroalcoholic extract 3% significantly decreased wound area on all days after wounding in comporison with the control (p<0.05). Also, this combination ointment caused a significantly improved fibroblast distribution in treated animals compared to other groups (p<0.05). Our data showed that co-administration of flaxseed oil 2%+Cinnamon hydroalcoholic extract 3% ointment had beneficial effects on wound healing.

Wound healing has always been of great concern for the surgeon and therefore using different effective biologicalsubstances of either plant or animal origin for a faster and more effcient wound healing (repair) has been considered.The aim of this study was to investigate the accelerating effects of Hypericumperforatumhydroethanolextracton open wound healing in rats. Study design: thirty-six adult male Wistar-albino rats (weight 200±10 g) wererandomly allocated to three groups (one control and two treatment groups). Two seven-mm, circular, fullthicknesses, skin wounds were created on the back of each rat (2 on the left and 2 on the right side). In the controlgroup, wounds were treated by an ointment with no extract. The treatment groups were treated by standardizedointment containing 1% and 2% Hypericumperforatum extract. For histopathological studies, the 3 groups weresubdivided into 4 subgroups with 4 rats in each. Samples were taken from the groups 1 to 4 on days 3, 7, 14, and21, respectively. After taking the sample, the rats were euthanized. The sequential wound biopsies were evaluatedhistopathologically for their heamorrage,neutrophils and lymphocyte, new vascularization and re epithelialization.According to the results of this study, the ointment with 2% extract was much better and slightly better than thecontrol and 1% extract ointments, respectively.