Microbiological quality of drinking water cooling system (water supplies) in some trains solid in Egypt

Abstract

Numerous microorganisms, including bacteria, fungi and algae, are present in water,forming a complex ecosystem. Among these organisms, bacteria and fungi are responsible for most of the contamination in drinking water and dieses that are intrinsic to the health public. On the bases of morphological and biochemical and serological we identified different bacterial and fungal isolates. Sixty-four fungal isolates (13 genus) were detected in a total 100 drinking water cooling system samples in some trains in Egypt. Suggested names including, Acremonium strictum (4%), Aspergillus flavus (2%), Aspergillus niger (2%), Aureobasidium (2%), Cladosporium (14%), Pseudallescheria boydii (12%), Fusarium cacasicum (8%), Fusarium moniliform (4%), Fusarium oxysporum (4%), Penicillium chrysogenum (8%), Penicillium corylophilum (4%), Phialophora bubakii (2%) and Phoma exigua (2%). Twenty-four bacterial isolates represent six genus were identified to species level, this including the following suggested names: Staphylococcus epidermidis (3%), Bacillus subtilis (3%), Pseudomonas aeruginos (2%), Pseudomonas pseudomallei (1%), Pseudomonas, mallei (1%), E. coli O157:H7 (2%), E. coli (type strain, 4%) Salmonella sp. (6%), (1%), and Enterobacter coloacae (2%). In addition to that seven heavy metals, Zn++, Cu++, Co++, Fe++, Pb++, and Cd++ were detected for hundred water samples under investigation. Antimicrobial susceptibility of the bacterial isolates was examined. All bacterial isolates were sensitive to Polymxin B, Tetracycline, Chloramphenicol, Amoxycillin clavulanic acid (augmentin) 2:1, Gentamycin, Kanamycin, and Sulphamethoxazole/ trimethoprim 19:1 respectively. On the other hand, four isolates were resistant to Bacitracin, one isolates was resistance to Ampicillin, four isolates were resistance to Penicillin G and two isolates were resistance to Nitrofurantion. The most effective microbial growth inhibitors were sodium azide, ZnCl2, CdCl2, NiCl2, CuC12 and FeCl2 (at 500, 200, 100, 50 􀈝/ml) respectively. On the other hand, EDTA and Urea, exhibited no effect at all on growth of bacterial isolates. Genus Bacillus and pseudomonas has ability to produce all extra-cellular enzymes with high productivity, genus E. coli weakly produced lipases and celluloses and do not produces either proteases or amylases, Genus Salmonella very weakly produces proteases and lipases and no produces neither cellulose nor amylases, Enterobacter, exhibited weakly producing to proteases, lipases, amylases, and not produce cellulases and genus Staphylococcus has no ability to produce extra-cellular enzyme at all. Data emphasized the fact that the train water cooling system has many microbial environmental problems, which may lead to series health problems for traveling peoples.