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Four chitosan‐poly(vinyl chloride), Cs‐PVC, conjugates were synthesized by primarily reacting amino‐PVC with chloroacetyl chloride to give 2‐chloro‐N‐(2‐aminoethyl) acetamide‐functionalized PVC (PVC‐AcCl) followed by conjugation with chitosan to yield a derivative of acetamide‐functionalized PVC chitosan (Cs‐AcPVC). On the other hand, a one‐pot reaction between PVC‐chloroacetyl chloride, benzimodazole, and chitosan produced benzimodazole‐functionalized PVC conjugates (PVC1). The above one‐pot reaction was repeated with incorporating silver nanoparticles, AgNPs, via in situ reduction of Ag salt to give PVC2 whereas silver treated titanium dioxide (Ag/TiO2)NPs was simply mixed with PVC1 to afford PVC3. Fourier‐transform infrared spectroscopy FTIR spectroscopic analyses of all the synthesized materials were studied. Morphological investigation such as scanning and transmission electron microscopy, and thermal gravimetric analysis were also carried out. The antibacterial activities of the synthesized conjugates were investigated against two Gram‐negative (Escherichia coli, and Salmonella typhimurium) and two Gram‐positive (Staphylococcus aureus, and Listeria monocytogenes) bacterial strains. The antibacterial assay showed that all PVC‐Cs conjugates exhibited excellent bacterial inhibition (five‐log10 reduction) at a concentration of 500 mg/L after 30 min and almost complete inhibition after 120 min. Minimum inhibition concentration investigation showed that conjugates PVC‐chloroacetyl chitosan and PVC3 were more potent than PVC1 and PVC2 against both Gram‐negative and Gram‐positive strains at 250 mg/L. These results suggested that all four polymeric conjugates might afford a revolutionary antibacterial polymeric material that can be useful in many applications such as water sanitization, food packaging, and biomedical devices. [ABSTRACT FROM AUTHOR]

Since knowledge and understanding of waterborne pathogens and their diseases are well illuminated, a few research publications on the prevalence of pathogenic microorganisms in various household sink drain pipes are often not extensively examined. Therefore, this study aims to (a) assess and monitor the densities of the bacterial community in the different natural biofilm that grow on plastic pipelines, (b) to detect Escherichia coli, Salmonella, and Listeria spp. from natural biofilm samples that are collected from the kitchen (n = 30), bathroom (n = 10), laboratories (n = 13), and hospital (n = 8) sink drainage pipes. Three bacterial species selected were assessed using a culture‐dependent approach followed by verification of isolates using both BIOLOG GEN III and polymerase chain reaction. The estimated number of each bacterium was 122 isolates, while 60, 20, 26, and 16 isolates were obtained from the natural biofilm samples, kitchen, bathroom, laboratories, and hospital, respectively. As for the tests, in all types of biofilm samples, the overall bacterial counts at low temperature (22°C) were higher than those at high temperature (37°C). Meanwhile, E. coli had the most significant number of bacterial microorganisms compared to the other two pathogens. Additionally, the most massive cell densities of E. coli, Salmonella, and Listeria species were discovered in the biofilm collected from the kitchen, then the hospital. Statistically, the results reveal that there is a positive correlation (p ≥.0001) with significance between the sources of biofilm. This work certainly makes the potential of household sink drain pipes for reservoir contagious pathogens more explicitly noticeable. Such knowledge would also be beneficial for prospective consideration of the threat to human public health and the environment. [ABSTRACT FROM AUTHOR]