Enhancement of A Cationic Surfactant by Capping Nanoparticles: Synthesis, Characterization and Multiple Applications.

There is scarce information on cationic surfactants' biocidal and corrosion inhbibition effects on Slime-Forming Bacteria (SFB) isolated from oil field formation water. Therefore, this work focused on the the synthesis of a cationic surfactant (CS) to increase its features by capping different metal nanoparticles (zinc, ZnNPs-C-CS; manganese, MnNPs-C-CS and tin, SnNPs-C-CS) and used them as biocides and corrosion inhibitors. The cationic surfactant was synthesized and characterized by Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. Afterwards, different nanoparticles were synthesized, characterized, and exploited to cap by the CS. The CS and the different nanoparticles capped by the CS were tested for their antimicrobial susceptibility against standard bacterial and yeast strains. The synthesized compounds were further evaluated as anti-biofilms agents against positively-developed bacterial biofilms. Moreover, the CS and the ZnNPs-C-CS, MnNPs-C-CS, and SnNPs-C-CS were assessed as potential biocides against SFB, particularly Pseudomonas sp. (isolated from contaminated formation water), and as corrosion inhibitors against cultivated salinity. The results revealed the great effect of the different CS-capped NPs as broad-spectrum antimicrobial and anti-biofilm agents at lower Minimum Inhibitory Concentrations (MICs), Minimum Bactericidal Concentrations (MBCs), Minimum Fungicidal Concentrations (MFCs) and Minimum Biofilm Inhibitory Concentrations (MBICs), and the activities were reported in order of SnNPs-C-CS > MnNPs-C-CS > ZnNPs-C-CS > CS. Furthermore, the ZnNPs-C-CS, MnNPs-C-CS, and SnNPs-C-CS demonstrated biocidal and corrosion inhibition effects against Pseudomonas sp. at a salinity of 3.5% NaCl, with metal corrosion inhibition efficiencies of 88.6, 94.0 and 96.9%, in comparison to a CS efficiency of 85.7%. In conclusion, the present work provides a newly synthesized cationic surfactant and has enhanced its antimicrobial and its metal corrosion inhibition effects by capping different nanoparticles, and it has been successfully applied against slime-forming bacteria at a salinity of 3.5% NaCl.

Genetic diversity within and among sinai populations of three Ballota species (Lamiaceae).

Ballota undulata, Ballota kaiseri, and Ballota saxatilis are very rare (and endemic--B. kaiseri), threatened species growing in St. Catherine Protectorate, southern Sinai, Egypt. They are subjected to a number of threats that have caused populations to decline in both number and size. For the long-term survival of these species, an appropriate conservation strategy for the maintenance of their genetic variation should be developed. This study measures genetic diversity within and among populations of these Ballota species and determines the conservation implications of the results. The genetic analyses demonstrated that the three Ballota species maintain relatively high levels of genetic diversity (He = 0.195-0.317) and that most of the their genetic diversity was found within populations (GST = 0.045-0.099). Indirect estimates of historical gene flow for B. undulata and B. saxatilis were relatively high (Nm(W) = 5.25 and 3.37, respectively) but suggest that there is somewhat less gene movement among B. kaiseri populations (Nm(W) = 2.29). The levels of genetic diversity maintained within populations of the three Ballota species indicate that an appropriate sampling design for ex situ safeguarding should capture the majority of the genetic diversity found within these taxa.