الفهرس 
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Abstract
The activity of 2 different paint samples to inhibit microbial growth was demonstrated against 12 clinical isolates isolated from patients suffering from serious illness. Both paints inhibited growth and colonization (biofilm formation) of both Gram positive (Staphylococcus aureus) and Gram negative (Pseudomonas aeruginosa) bacteria with different extents. All methicillin and vancomycin resistant strains of Staphylococcus aureus were susceptible to both paint samples (Tables 13, 14, Fig. 21 and 24). Paint IIc was more effective compared with Paint Vb. However, only one strain (Sa1) the opposite was true. Since, Paint IIc did not contain toxic material compared with paint Vb, paint IIc was preferable to be used compared with paint Vb. In addition, the two paint samples were able to inhibit the growth and colonization of 2 multi-drug resistant strains of Pseudomonas aeruginosa. Sensitivity of Pseudomonas aeruginosa strains was lower than Staphylococcus aureus. Antagonistic effect was detected after mixing all the additives with the other ingredients of both paints. This showed that after paint casting, the active additives were chelated in the epoxy paint thus reduce their activity. The activity of paint samples did not change after 3 months of preparation with the same efficiency. The results agreed with [87] that aliphatic amines (ingredient of IIc) were more efficient against the Gram positive bacteria.
Quaternary ammonium compounds (QACs) of C16 hyDROPhobic tail length affected the outer membrane of Gram-negative bacteria more extensively than shorter chain compounds, possibly due to the C16 chain interact strongly with the fatty acid portion of lipid A. It was also reported that monoalkyl QACs bind by ionic and hyDROPhobic interaction to microbial membrane surfaces, with the cationic head group facing outwards and the hyDROPhobic tails inserted into the lipid bilayer causing rearrangement of the membrane and subsequent leakage of intracellular constituents. [88] Reported that a common feature of QACs is their ability to cause cell leakage and membrane damage, primarily due to their adsorption in large amounts to the bacterial membrane [89].
Surface-active agents, including non-ionic surfactants, are known to disrupt cell membranes because they dissolve in both extracellular fluid and the lipid membrane. This lowers the surface tension of the membrane, allowing water to flow into the cell and ultimately resulting in lysis and bactericidal action. The balance between the hyDROPhilic and lipophilic sections of the molecules is essential for these processes. The irritating properties of cationic surfactants have been one of the major limitations to a widespread use of this type of surfactants with known bactericidal activity, in personal care products. In personal hygiene as well as in the cosmetic industry, the association of a low antibacterial activity with emulsifying potential is desirable in order to clean and simultaneously cause the least disturbance in the normal skin flora and moisture balance. Therefore, the antimicrobial activity of the new surface-active glycosides was also evaluated, using the paper disk diffusion method [90].