فهرست مطالب alireza yazdinejad

 Oral health is part of general health. Dental caries is the most common chronic disease worldwide. Considering the significance of plaque control, complications of chemical agents, and the optimal antimicrobial efficacy of nanoparticles, this study aimed to assess the antimicrobial activity of silver nanoparticles (AgNPs) synthesized by the green method using Rhus coriaria L. extract against oral pathogenic microorganisms.

 In this in vitro experimental study, Rhus coriaria fruit was dried at room temperature. It was then ground, and its aqueous extract was obtained by the maceration technique. The effects of AgNPs synthesized by the green method in different concentrations were evaluated against Enterococcus faecalis (E. faecalis), Streptococcus mutans (S.mutans), Streptococcus sobrinus (S. sobrinus), Lactobacillus acidophilus (L. acidophilus), and Streptococcus salivarius (S. salivarius) using the well-plate technique. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were also calculated. Data were analyzed by the Wilcoxon test, Kruskal-Wallis test, and Mann-Whitney test.

 The MIC values were 1024 µg/mL for S. mutans and E. faecalis, and 512 µg/mL for S. sobrinus, S. salivarius, and L. acidophilus. The resistance of S. mutans and E. faecalis was higher than that of S. sobrinus, S. salivarius and L. acidophilus. According to the growth inhibition zones and MBC test results, S. salivarius had the highest resistance to AgNPs followed by L. acidophilus, S. sobrinus, S. mutans, and E. faecalis. 

 AgNPs synthesized by the green method using Rhus coriaria extract was effective against oral pathogenic microorganisms. Thus, they may be used in the formulation of mouthwash and toothpaste.

Root rot is one of the important diseases of bean in Zanjan province and two fungal pathogens، Rhizoctonia solani and Fusarium solani are the major causal agents of this disease in the region. In this research، the inhibitory effect of N-hexane، di-ethyl-ether، chloroform and ethanol extracts of five plant species، hermel (Peganum harmala)، thyme (Thymus kotschyanus)، yarrow (Achillea wilhelmsii)، pennyroyal (Mentha pulegium) and garlic (Allium sativum) on mycelial growth of R. solani and F. solani was studied using poisoned food technique at four levels of 100، 250، 500 and 1000 ppm with three replications. After laboratory experiments، the most effective extracts، were applied against bean root rot under green house conditions. According to the results from in vitro studies، N- hexane extract of thyme and pennyroyal (both at the level of 1000 ppm) had the most inhibitory effect against both pathogens and also caused cytoplasm granulation and leakage of intracellular compounds of hypha of both fungi. At greenhouse experiments، hexane extract of thyme and menthe not only significantly reduced the root rot percentage، but also had significant increasing effect on most plant growth parameters (P = 0. 05).