تأثير مستخلصات قشور بعض الثمار على ضراوة بعض انواع البكتريا الممرضة المعزولة من اصابات المجاري البولية في النساء الحوامل في كريلاء

Effect of some fruits peel extracts on the virulence of some pathogenic bacteria isolated from urinary tract infection in pregnant women in Karbala

The present study included the isolation and identification of pathogenic bacteria responsible for urinary tract infection in pregnant women, attending Maternity and Women’s Hospital in Karbala province during the period from December 2011 till March 2012.

A total of 100 morning mid-stream urine samples from pregnant aged from 16 to 40 years were streaked on general and selective media, then the growing bacteria were diagnosed biochemically and by used Api kits.

The results revealed the occurrence of 52 isolates of pathogenic bacteria which is divided to Gram– positive bacteria 43 (83%) which represented by coagulase positive Staphylococcus aureus 20 (39%); coagulase negative Staphylococcus spp. 15 (29%), Streptococcus spp.  8(15%) and Gram – negative bacteria 9 (17%) which is divided between Escherichia coli 6 (11%) and Klebsiella  spp. 3 (6%). Then the ability of S. aureus and E. coli bacteria which are responsible for the highest percentage of urinary tract infection to form biofilm were tested by using tube methods (TM), in order to select one isolate from S. aureus and other one from E. coli which had the higher ability to form the biofilm for continue the other steps of these study. Then the ability of these two isolates to form some virulence factors such as hemolysin; protease; β – lactamase and adherence are tested.

After screening 11types of the fruits peel extracts including (apple, banana, cucumber, lemon, muskmelon, peach, pummel, pomegranate, sour orange, sweet orange and watermelon) which had been extracted by three solvents (alcoholic 96%, aqueous and the acetone 70%), the results revealed that only the pomegranate had the ability to be as the antibacterial on the studied S. aureus and E. coli bacteria. The inhibition zones diameters of the pomegranate peel extracts against studied bacteria increase significantly with concentrations increase to reach for S. aureus to 1.88 cm in 0.1 g/ml from aqueous extract and 2.26 cm for alcohol extract, but the inhibition zone diameter for the acetone extract was 2.5 cm at the same concentration. While the 1.78 cm, 2.36 cm and 2.33 cm were considered the inhibition zones diameters against E. coli when used 0.1 g/ml from aqueous, acetone and alcohol extracts respectively.

The  three extracts of the pomegranate peel contain alkaloid, tannins, phenolic, glycosides and resins, while the flavonoids and saponins were absent in aqueous extract but ethanol extract did not have saponins only.

The MIC of the extracts was determined against studied bacteria which reached to 0.04 g/ml when used both the ethanol and the acetone extracts, while reached to 0.06 g/ml in the aqueous extract. The ability of two isolates to produce virulence factors were compared by using MIC before and after treated with extracts which revealed there is not effect of the extracts on the ability of bacteria to produce hemolysin and protease enzymes, while both S. aureus and E. coli bacteria loss its ability to produce β – lactamase enzyme after treated with MIC of the pomegranate peel extracts, in contrast with bacteria which were not treated with the extracts.

The ability of S. aureus and E. coli bacteria to form biofilm after treated with MIC of the extracts. The results were 0.76, 0.58 and 0.35 when E. coli treated with the aqueous, the acetone and the ethanol pomegranate peel extracts respectively (In comparison with E. coli without extracts which reach to 1.5). While S. aureus results were 1.7 without extracts, but reached to 0.86, 0.85 and 0.12 in the present of the aqueous, the acetone and the ethanol pomegranate peel extracts respectively.

The three extracts were vary largely in their effect on adherence activity for these bacteria, S. aureus adhered cell declined after treated with the extracts to be with the aqueous extract10 bacteria /cell only but reach to 3 and 1 bacteria /cell in the presence of the acetone and the alcohol extracts respectively, while S. aureus adhered cell was 40 bacteria/cell when the extracts did not find. The adherence of the E. coli bacteria reached to one bacteria /cell when the acetone extract added to bacterial suspension, but only three bacterial cell seen attached to epithelial cells after the bacterial suspension incubated with the alcohol extract, while only 5 bacteria / cell remain attached after the aqueous extract was added, in contrast with the control E. coli without extracts which was 20 bacteria /cell.

The used of the ethanol extract together with chloramphenicol and ciprofloxacin antibiotics against S. aureus was synergy, while in the studied of E .coli bacteria, found that the synergy appear only in the interaction between the Tetracycline and the acetone extracts, but at the case of the ethanol extracts and the chloramphenicol which was additivity.