عزل وتشـخيص بعض انواع البكتريا المسـببة لإصابات المسالك التنفسـية وتقـيـيم كفـاءة تثبيطها بأسـتخـدام المضادين أزيثرومايسين وسبروفلوكساسين المحضرين نانوياً

Isolation and Identification of some bacterial species causing respiratory tract infections and evaluation their inhibitory efficiency using nanoprepared azithromycin and ciprofloxacin

Abstract

This study included the isolation and identification of the most important types of bacteria that cause respiratory tract infections. The isolated bacteria were identified by conventional and molecular methods. It also included the preparation and identification of two hybrid nanocomposites of the antibiotic azithromycin and ciprofloxacin. The inhibitory effect of the two nanoparticles prepared above against the isolated bacteria was evaluated in this study, and the results were shown as follows:
From a total of 60 samples taken from respiratory tract infections patients attended to AL-Hussein Medical City in the Holy Karbala Governorate , 48 isolates and four yeasts isolates were obtained , which included 12 isolates (23%) of Klebsiella Pneumoniae and 14 isolates 26.9 % Of Streptococcus that divided into 4 (7.7%) of Streptococcus agalactiae and Streptococcus pneumoniae, 3 (5.7%) Streptococcus pyogenes, 2 (3.8%) of Streptococcus salivereus and one of them (1.9%) of Streptococcus viridans and 7% (of 13.4 isolates) Sphingomonas sp., 4 isolates (7.7%) of Staphylococcus aureus, E.coli and Candida albicans, 3 isolates (5.7%) of Pseudomonas aeruginosa, and two isolates (3.8%) each of Entreococcus faecium and Enterobacter aerogenes.
The antibiotic azithromycin was used in the preparation of a hybrid nanocomposite after loading the antibiotic with zinc oxide. The results of characterization by infrared spectroscopy (FT-IR) showed that the frequencies of some chemical groups were shifted towards high and low frequencies. X-ray diffraction (XRD) also revealed the appearance of new diffraction planes in the spectrum of the Azi-Zno hybrid antibiotic compared to the spectrum of the zinc oxide carrier, indicating that the prepared antibiotic under study was a nanohybrid antibiotic . The results of Atomic Force Microscope (AFM) revealed that the average dimensions of the Azi-Zno nano hybrid antibiotic were 51.58 nanometers. Results of scanning electron microscope (SEM), revealed the appearance of regular geometric shapes as well as the formation of structures with high porosity when the Azi-ZnO nano hybrid antibiotic was formed by the direct intercalation of the zinc oxide layers with the free Azithromycin antibiotic , which indicates the success of the antibiotic insertion into layers of Zinc oxide. The analysis by (EDS) spectroscopy confirmed the presence of zinc, oxygen and carbon elements in the composition of the Azi-ZnO nano hybrid antibiotic , which indicates the success of the free antibiotic intercalation between the zinc oxide layers and thus the formation of a new nano hybrid antibiotic .
Ciprofloxacin was also used in the preparation of a hybrid nanocomposite after loading the antibiotic with magnesium oxide. Results of infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) indicated that the prepared antibiotic under study was a nanohybrid antibiotic. Results of atomic force microscope (AFM) revealed that the average dimensions of the Cip-MgO nano hybrid antibiotic reached 77.35 nanometers.
Scanning electron microscope (SEM) image revealed the appearance of shapes similar to thin sponge pieces as well as the formation of structures with high porosity when the Cip-MgO nano hybrid antibiotic was formed by the direct intercalation of magnesium oxide layers with the free Ciprofloxacin antibiotic, indicating the success of the antibiotic intercalation into layers of magnesium oxide. As for the analysis with EDS spectroscopy, the presence of magnesium, oxygen and carbon elements in the composition of the Cip-MgO nano hybrid antibiotic indicates the success of the free insertion of the free antibiotic between the magnesium oxide layers and thus the formation of a new nano hybrid antibiotic.
The inhibitory activity of nanohybrid antibiotic prepared in this study was evaluated against K.pneumonia isolates. The results showed the following:
The Azi-ZnO nano hybrid antibiotic had the highest inhibitory activity against K.p5 and K.p11 isolates with rates of inhibition diameters of (29.25 and 28.25) mm, while the isolates K.p 4, K.p7, K.p10, K.p11 and K.p12 were the most affected by the inhibitory effect of Azi-Free antibiotic with inhibition diameters (31.5, 31.5, 32, 32.5 and 31.5) mm, respectively.
The nano hybrid antibiotic Cip-MgO showed the highest inhibitory activity against isolates K.p 3, K.p 7, K.p 9, K.p 10, K.p 11 and K.p 12 with inhibition diameters of (32.5, 32.5, 32.5, 33, 33.25 and 34 mm), respectively. , While the highest inhibitory activity of the free ciprofloxacin was against the bacterial isolates (K.p10, K.p11 and K.p12) with inhibition diameters (34.5, 35 and 35) mm, respectively.
The inhibitory activity of the two nano hybrid antibiotics prepared in this study was also evaluated against some Gram positive bacterial isolates .
The results showed the following:
Azi-ZnO nano hybrid antibiotic showed the highest inhibitory activity against S.pneumonia 1 bacterial isolate with an inhibition diameter of 29.75 mm, while the highest activity of free antibiotic against bacterial isolates E .faecium 1, S .pneumonia 1 and S .pneumonia 4 with inhibition diameters of (30.5, 31.5, and 30.5) mm, respectively. Whereas, the free and nano hybrid ciprofloxacin antibiotic showed the highest inhibitory efficacy against S. agalactia 4 bacterial isolate with inhibition diameter (30 and 29) mm, respectively.