نوفل حسين خضير الدجيلي

Metals that contain nanomaterials have the potential to be employed in controlling different kinds of infection, however, very limited information is known about their antibacterial properties. This study has been done to investigate the nanosynthesis titanium nanoparticles (TiNPs) using Streptococcus thermophilus and weighing their biological actions as antibacterial. The bacterial isolates identified using universal primers 16S rRNA; then The 16S rRNA gene nucleotide sequences were aligned with the nucleotide sequences of strains obtained from the GeneBank through the software CLUSTAL X (version 1.82). Titanium nanoparticles were nanosynthesized by adding 0.025M titanium dioxide (TiO2) into cell-free supernatant for Streptococcus thermophilus. TiO2 was used as a precursor for nanobiosynthesis TiNPs. The formation of TiNPs was indicated by the color alteration of the solution from the light brown into dark brown indicates for the production of TiNPs. The Characterization of nanobiosynthesis was accomplished with UV-Visible (absorbance at 377nm), Scanning Electron Microscope, X-ray diffraction, Atomic Force Microscope, Energy-dispersive X-ray spectroscopy was used to distinguish the dimension, form (spherical) by SEM, dispersal (homogenous) and elemental analysis of nanoparticles. Biogenic TiNPs have displayed antibacterial and antibiofilm activity against both Multidrugresistant Klebseilla pneumonia and Staphylococcus aureus. As an antibacterial activity, the TiNPs inhibited significantly K.pneumoniae (20mm) with concentration (500μg/ml), and S. aureus (16mm) with the same concentration and increasing the concentration of TiNPs the inhibition zone increased. While as antibiofilm activity of TiNPs using the tube method, the tubes containing bacterial suspension K.pneumoniae and S.aureus with TiNPs, the results showed biofilm formation was prevented and removed by the effect of TiNPs.

Background: There are many studies highlight the association between Helicobacter pylori seropositivity with typhoid fever in human populations and there is no study in Iraq. Aim: Our study designed to estimate the correlation between seroprevelace of H. pylori and Typhoid fever in clinically examined patients as dyspeptic and typhoid fever infected. Methods: From May (2016) to February (2018), a total of 213 patients (134 females and 79 male) attending an enterology outpatient clinic in AL-Najaf province, Iraq. The patients with age range from 10 to 90 years and with symptoms of dyspepsia and typhoid fever (as fever, diarrhea, headache), were referred to serologic diagnosis of antibodies against H. pylori (IgG) and Typhoid (IgG and/or IgM), using the Rapid Tests Cassette. Results: Of a total of 213 clinically examined as dyspeptic and typhoid fever infected patients, 134 (63.0%) were females and 79 (37.0%) were males .In this study, 82 (38.5%) of 213 patients were seropositive for typhoid fever and 131 patients were seronegative. Moreover, 128 (60.1%) of 213 patients were seropositive for H.pylori IgG (51 case ,39.8%, typhoid seropositive, and 77 case, 60.2%, typhoid seronegative) and 82 were seronegative. The serologic co-infection diagnosed in 51 (24.0%) patients. The seropositivity of typhoid fever was higher in H. pylori seropositive patients, co-infections (62.2%), than H. pylori seronegative patients (37.8%). The co-infection was more in female (64.7%) than male (35.3%). In respect of age H. pylori seropositivity was more prevelance (25.8%) in 30s age group where as co-infection was more prevalence in 40s age group (29.4%). But the statistical analysis showed insignificant association of H. pylori with typhoid fever (P value = 0.6203), gender (P value = 0.4770) and age groups (P value = 0.0745). Conclusion: Our study indicates that H. pylori seropositive dyspepsia more susceptiple to typhoid fever particularly in female and 40s ages and suggest there was insignificant relationship amongst seropositivity of H. pylori and typhoid fever within dyspepsia patient.

Aim: The use of beneficial bacteria in conjunction with antibiotics may decrease the effects of dysbiosis initiated by the antibiotics, and maximize the assistance of probiotics in the gut in terms of exclusion and immune stimulation. Samples of Alcaligenes faecalis from burns were nominated for detection and identification according to morphological and biochemical tests, the VITEK-2 Compact System, and molecular sequencing by 16S rRNA. Materials and Methods: Antibiotic susceptibility was ascertained by determining the inhibition length of A. faecalis against three antibiotics from varied classes (based on the VITEK 2), which consequently showed resistance to ceftriaxone (10 mm), high resistance to trimethoprim– sulfamethoxazole (SXT) (8 mm), and sensitivity to imipenem (20 mm). The sensitivity of A. faecalis to Enterococcus faecium, Streptococcus thermophilus, and Bacillus subtilis was determined using Mueller-Hinton agar (MHA) with wells of diffused agar. Results: B. subtilis performed best against A. faecalis isolates compared to E. faecium and S. thermophilus, where the area of inhibition was 28 mm. This study dealt with the enhancement of the inhibition zone of antibiotics (imipenem, SXT, and ceftriaxone) by B. subtilis against A. faecalis. Conclusion: The potentiation of antimicrobial activity was observed by imipenem in combination with B. subtilis (32 mm) and B. subtilis with ceftriaxone antibiotics (20 mm). The inhibition action was not affected by SXT (8 mm).

ABSTRACT : Silver rich soil samples were screened for the potent bacteria for AgNPs biosynthesis. Silver resistant bacteria are the potent for AgNPs biosynthesis. K. pneumoniae strain HHHS1 was isolated and characterized using 16sRNA gene sequencing and VITEK-II and used for extracellular synthesis of AgNPs by cell free supernatant of BHI culture media. Conditions of synthesis were optimized and biogenic AgNPs were characterized physically using SEM, EDS, AFM and XRD and biologically by examining for antibacterial, antibiofilm and antioxidant activity. Sequencing of 16sRNA gene and distance tree analysis revealed that the isolated K. pneumoniae is a new strain submitted to the NCBI as HHHS1. SEM, EDS, AFM and XRD analysis for biogenic AgNPs fabricated by this strain revealed spherical, monodispersed NPs with average size 21.9 nm. Optimum conditions of the synthesis environment were found: pH 8, 370C, 8h, substrate concentration was found proportional to AgNPs characteristic.

Objective: The objective of the present study is the biosynthesis of silver nanoparticles using probiotic, Saccharomyces boulardii and evaluating their biomedical activity. The biological method of nanoparticles synthesis acquires very important area due to their cost-effective and eco-friendly benefits over chemical and physical methods of synthesis. Methods: AgNPs were biosynthesized by adding silver nitrate (AgNO3) into cell free supernatant of S.boulardii at concentration (10 mM). Results: The PCR was accomplished to molecular identification of S.boulardii using specific primers for (CAG) microsatellite repeat at locus YLR177w, foreword primer (Boul 3) and reverse primer (Boul 4). Biosynthesis of AgNPs was firstly indicated by the colour alteration of reaction mixture from yellow into reddish brown. The characterization completed by XRD, SEM, EDS and AFM. The XRD presented the size of AgNPs was 19nm.The SEM was offered the shape was spherical and homogenous and the size was ranged between 63-100nm. The occurrence of elemental silver was analysed by EDS. The AFM displayed the three dimensional structure of silver nanoparticles and the average diameter was 97.44 nm. Biosynthesized AgNPs showed antibacterial activity against multidrug resistant bacteria(MDR) of both gram positive and gram negative bacteria (S.aureus, S.pyogenes, E.coli, K.pneumoniae, E.aerogens, S.typhi, A.baumannii, P.auroginosa and P.mirabilis). All tested bacterial isolates revealed their ability to form biofilm in the form of biofilm using tube and Congo red method without treated by the nanoparticles except P.mirabils, A.boumanii and E.aerogenes,but when treated with AgNPs this ability was prevented and removed in K.pneumoniae, Ps.auroginosa and C.neoformans. The AgNPs at two concentration 1mg/ml and 2mg/ml bared their antioxidant capacity in vitro by scavenging DPPH free radicles, the largest inhibition titer found in the mixture of DPPH with biogenic AgNPs and supernatant of S.boulardii at concentration 2mg/ml (87.43).

تمت مناقشة طالب الدكتوراه في يوم 19/7/2020