In the present study five PGPR were isolated from Casuarina rhizosphere, coastal Odisha, India and were identified as B. acidiceler, Sphingomonas paucimobilis, Kocuria kristinae, B. subtilis and B. megaterium by 16SrDNA sequencing. The production of IAA by five PGPR ranges from 1.34 µg/ml to 2.509 µg/ml in absence of tryptophan whereas 3.103 µg/ml to 7.929 µg/ml in presence of tryptophan by using Salkowski’s reagent. The optimum activity of five PGPR was recorded at 2 mg/ml of tryptophan concentration. The optimum temperature and pH for IAA production by five PGPR were recorded at 30oC and 7.0. Partial purification of tryptophan was also done by TLC with Rf value 0.9. It is also found that the five PGPR have potential in the elongation of root length of rice plant grown in saline soil.

Background and Objective: Currently, many valuable drugs have lost their impact on Escherichia coli, and Escherichia coli drug resistance is the major reason for the treatment failure of nosocomial infections caused by this bacterium. This study aims to investigate the effect of silver nanoparticles using yogurt Lactobacillus flora on Escherichia coli with multiple drug resistance. Materials and Methods: This cross-sectional-experimental study was conducted in 2019 on Escherichia coli strain from some clinical centers in Ardabil, Iran. The isolates were performed based on approved biochemical tests to identify Escherichia coli bacteria. Antibiotic susceptibility testing was carried out by diffusion method. Then, its physical and chemical properties were determined by spectrophotometry (UV), SEM microscopy, and FESEM. Then, the synergistic effect of silver nitrate growth inhibitor was investigated using yogurt Lactobacillus flora by disk diffusion method according to standard (CLSI). Findings: In the present study, out of 100 samples, 37 strains of Escherichia coli were positive. The highest resistance of Escherichia coli isolates was to ciprofloxacin with 87% and the highest susceptibility was to nitrofurantoin with 76%. The size of silver nanoparticles according to the image of TEM and FESEM was both shown to be 16 nm in diameter. Silver nitrate using yogurt lactobacilli flora was able to reduce the combination of Escherichia coli strains with antibiotics, especially ciprofloxacin. Conclusion: The results of the present study showed that silver nanoparticles synthesized using yogurt lactobacilli flora with a diameter of 16 nm have antimicrobial activity against Escherichia coli. Considering the effectiveness of silver nanoparticles using yogurt Lactobacillus flora on ciprofloxacin-positive Escherichia coli, it can be used as a candidate drug against Escherichia coli in the future.

Acinetobacter sp bacteria especially Acinetobacter baumannii has emerged as a problematic multidrug-resistant (MDR) pathogen worldwide. Acinetobacter baumannii are important healthcare-associated pathogens, widely distributed in soil, water, and commonly found in the hospital environment as opportunistic pathogens from a neonatal intensive care unit and an intensive care unit (NICUs and ICUs) these bacteria formed as major nosocomial infections in hospitals environment all over the world and in the Middle East. The aim of this study was to characterize clinical isolates of A. baumannii from Qasim Area, Saudi Arabia that has an in this study, 217 nonrepetitive clinical isolates of A. baumannii were identified through MALDI-TOF and susceptibility was determined with VITEK-2 systems . Genotypic characterization of the isolates was performed by using index1,2 primers typing and polymerase chain reaction screening was performed for carbapenemase genes, insertion sequences, metallo-β-lactamases, and cephalosporinase genes. The isolates were recovered from heterogeneous clinical specimens, and the majority of the cases of A. baumannii infection were acquired in the hospital and predominantly involved patients who were older than 50 years. Total, 57.7% of the isolates were MDR, and 56.8% isolates were resistant to carbapenem antibiotics. Approximately half of the isolates were resistant to cefepime, and ceftazidime among the β-lactam antibiotics and ciprofloxacin from the quinolone group. The blaOXA-23-like gene and ISAba1 upstream of blaOXA-23-like were detected in 93% of the carbapenem-resistant isolates, while all carbapenem-resistant isolates were found to carry blaOXA-51-like, and blaADC-type cephalosporinase gene. Data demonstrate the coexistence of multiple carbapenem resistance determinants in A. baumannii from the Qssim region of Saudi Arabia.