پديد آورندگان :
سوسني غريبوند، زهره دانشگاه علوم كشاورزي و منابع طبيعي خوزستان - دانشكده علوم دامي و صنايع غذايي - گروه علوم و مهندسي صنايع غذايي، ملاثاني، ايران , عليزاده بهبهاني، بهروز دانشگاه علوم كشاورزي و منابع طبيعي خوزستان - دانشكده علوم دامي و صنايع غذايي - گروه علوم و مهندسي صنايع غذايي، ملاثاني، ايران , نوشاد، محمد دانشگاه علوم كشاورزي و منابع طبيعي خوزستان - دانشكده علوم دامي و صنايع غذايي - گروه علوم و مهندسي صنايع غذايي، ملاثاني، ايران , جوينده، حسين دانشگاه علوم كشاورزي و منابع طبيعي خوزستان - دانشكده علوم دامي و صنايع غذايي - گروه علوم و مهندسي صنايع غذايي، ملاثاني، ايران
كليدواژه :
عصاره آبي , برگ شيشه شور , نانو ذرات نقره , باكتري هاي گرم مثبت , باكتري هاي گرم منفي
چكيده لاتين :
Introduction: Nowadays, production and utilization of Nano materials have increased due to their unique and interesting properties. So far, different physical and chemical methods have been used to synthesize silver nanoparticles.
Chemical synthesis is not compatible due to the hazardous chemicals residues on the surface of the nanoparticles (NP) as
well as production of by products with high impact on the environment. Physical routes for synthesis of NPs have some
drawbacks, too. These methods require high energy and space, and are expensive. Therefore, biological methods for the
synthesis of silver nanoparticles are considered emerging technologies as economic choices in the green chemistry field.
Among these methods, plant-mediated synthesis of AgNPs is a rapid, simple, non-toxic and eco-friendly technique. Silver
nanoparticles exhibit high bactericidal activity at their utilized concentrations with no toxic effect on human cells, and
they also strongly enhance the antibacterial activity of conventional antibiotics even against multi-resistant bacteria
through their synergistic effects. Callistemon citrinus belongs to the family Myrtaceae and includes more than 30 species.
The plant is widespread in wet tropics, notably Australia, South America and tropical Asia, but presently can be found all
over the world. Callistemon citrinus is a potential medicinal plant used to treat gastrointestinal distress, pain, and
infectious diseases caused by bacteria, fungi, viruses, and parasites. In this study Callistemon citrinus aqueous extract
was used to reduce silver ions in silver nitrate solution. In the following, the antimicrobial activity of nanoparticles
synthesized by various qualitative and quantitative methods on Escherichia coli, Staphylococcus aureus, Pseudomonas
aeruginosa, Salmonella typhi and Listeria innocua was investigated. Materials and Methods: For the synthesis of silver nanoparticles, 25 mL of silver nitrate solution was added to 5 mL
of leaf extract with a concentration of 100 mg/mL and maintained for 24 h at 20 °C. Change the color of the solution to
Red represents the production of silver nanoparticles in the solution. To stabilize the presence of silver nanoparticles, the
absorption spectrum of silver nanoparticles produced by spectrophotometer was prepared. Antimicrobial activity of silver
nanoparticles synthesized using Callistemon citrinus leaf aqueous extract was examined by disc diffusion agar, well
diffusion agar, minimum inhibitory concentration (microdilution broth) and minimum bactericidal concentration on
Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi and Listeria innocua.
Results and Discussion: The results showed that in disc diffusion agar method, the diameter inhibition zone increased
with increasing the concentration of silver nanoparticles. The maximum effect of silver nanoparticles synthesized using
Callistemon citrinus leaf aqueous extract at a concentration of 150 mg / ml was observed for Pseudomonas aeruginosa.
An inhibition zone was observed for all examined pathogenic microorganisms at all concentrations. The results showed
that in the well diffusion agar method, nanosilver particles at a concentration of 18.75 mg/ml did not show any inhibitory
effect on all the pathogenic microorganisms. The results of statistical analysis showed that there was no significant
difference between all the concentrations of silver nanoparticles synthesized for Escherichia coli, Salmonella typhi and
Staphylococcus aureus (P˂ 0.05(. The MIC for Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhimurium and Listeria innocua was 128, 256, 256, 256 and 512 mg/mm, respectively. The MBC for all
the pathogenic strains was 512 mg/mm. The results of this study showed that the Callistemon citrinus leaf extract has a
good ability to synthesize silver nanoparticles. Nanoparticles synthesized from Callistemon citrinus leaf extract had good
antimicrobial activity against examined pathogenic bacteria, especially Gram-negative bacteria. Green-synthesized
nanoparticles can be used as antimicrobial agent to fight infectious diseases caused by various microbial strains, although more research is needed in vitro, animal models and in vivo.
