Aim: To evaluation the effect of Lactobacillus acidophilus on Enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 with detection of some virulence factors. Methods: Two hundred and fifty specimens (stool) from children under five years for both sexes were collected from some hospitals. All isolates were diagnosed according to morphological characteristics, biochemical tests. Monoplex pattern of PCR was used also for detection different genes in (7) Escherichia coli )O157:H7 (isolates; include 16SrRNA, eae, lifA, Stx1,Stx2 that encoded for ribosomal RNA, intimin, lymphocyte inhibitory factor, shiga toxins. Three types of probiotics strains were obtained, Lactobacillus fermentum, Lactobacillus plantarum and Lactobacillus acidophilus (ATCC4356). Minimum inhibitory concentration (MIC) of cell free supernatants of Lactobacillus acidophilus was determined by employing different dilutions (1/2, 1/4, 1/8, 1/16, 1/32), to detect the concentration of probiotic that will inhibit E.coli (O157:H7) growth. Results: Results showed, 210 (84%) samples were identified as E.coli from 250 samples. The result showed (7) isolates were identified as Enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 and showed all isolates of O157:H7 were positive for 16SrRNA gene with (213bp) and eae with (741bp), lifA with (712bp), only Stx1 gene appeared in all isolates with (446bp) and no bands with Stx2. Current result showed only cell free culture supernatant of Lactobacillus acidophilus has inhibitory activity against all E.coli (O157:H7) isolates with different dilutions (1/2, 1/4, 1/8, 1/16, 1/32), while Lactobacillus fermentum, Lactobacillus plantarum have no effect against E.coli (O157:H7). The result showed the bacteriocin has inhibitory effect against E.coli (O157:H7), while organic acids and hydrogen peroxide haven’t any role in inhibition. The (MIC) value was (1/8) which inhibits the bacterial growth of isolates.
Two simple methods for the determination of eugenol were developed. The first depends on the oxidative coupling of eugenol with p-amino-N,N-dimethylaniline (PADA) in the presence of K3[Fe(CN)6]. A linear regression calibration plot for eugenol was constructed at 600 nm, within a concentration range of 0.25-2.50 μg.mL–1 and a correlation coefficient (r) value of 0.9988. The limits of detection (LOD) and quantitation (LOQ) were 0.086 and 0.284 μg.mL–1, respectively. The second method is based on the dispersive liquid-liquid microextraction of the derivatized oxidative coupling product of eugenol with PADA. Under the optimized extraction procedure, the extracted colored product was determined spectrophotometrically at 618 nm. A l
... Show MoreOur research comes to shed light on Iraqi literature as literature that arose in special circumstances alongside foreign literature. Using comparative research methods, we chose to highlight two distinguished writers, who have their mark in the world of literature. The first is the Iraqi writer Maysaloun Hadi, who is considered an icon of Iraqi feminist literature, and the second is the French writer Le Clézieu, who won the Nobel in 2008. We will see through the research how the two authors expressed their views of modernity and urbanism. And how each of them separately portrayed the psychological and moral projections that formed the essence of man today.
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Notre recherche abord un des points inc
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