As the society begin to realize the importance of combating antimicrobial resistance, going
back to silver might be the solution. Silver has been known for its potential antimicrobial
activity since ancient times and, the development of nanoparticles has increased its potential
into becoming an antimicrobial agent that can be applied in broad-spectrum. Antimicrobial
resistance has spread into an irrepressible manner which requires drastic action plan as a number
of pathogenic bacteria began to acquire resistance genes. Methicillin Resistant Staphylococcus
aureus (MRSA) is one of the earliest reported resistant clones which is the center of this study.
This study focused on the dissemination and evolution of MRSA on its resistance towards
antibiotics. Disc Diffusion Test was employed to create the antibiograms of MRSA isolates. All
isolates showed resistance towards amoxicillin, ampicillin, cefazolin, oxacillin and penicillin.
In contrast, all isolates were susceptible towards erythromycin. The findings also discovered
isolates that were vancomycin-resistant (66.7%) and vancomycin-intermediate (33.3%). As the
efficacy of antibiotic treatment is at a question, we also investigated on the antimicrobial activity
of colloidal silver in the hope as an alternative treatment. Shiga Toxin producing Escherichia
coli (STEC) and MRSA (ATCC 33591) was tested using modified Quantitative suspension
test for the evaluation of bactericidal activity for chemical disinfectants and antiseptics based
on BS EN 1276:2009. The outcome of this study indicated that the colloidal silver is working
effectively against STEC and MRSA (ATCC 33591), showing killing percentages well above
99.0% at 4 minutes and 8 minutes of contact. Vancomycin-resistant S. aureus (VRSA) and
Vancomycin-intermediate S. aureus (VISA) were also tested and the results indicated that
VISA had higher killing percentages at 4 minutes (99.83%) and 8 minutes (99.85%) compared
to VRSA at 4 minutes (96.72%) and 8 minutes (98.35%). This opens a solution to the rising
problem of antimicrobial resistance.
Salmonellosis is an important public health problem and causes large economic losses in the poultry industry. The emergence of molecular technology has opened various possibilities for constructing tailor-made proteins, particularly protein E from bacteriophage PhiX174 for the
production of bacterial ghosts (BGs) applied in vaccines purposes. In the present study, the plamdaPRcI-Elysis plasmid carrying the PhiX174 lysis gene E and thermo-sensitive lamda PR-cl857 regulatory system was constructed. Two Salmonella Enteritidis (SE-2 and SE- 4) and one Salmonella Typhimurium (ST-4) isolates were able to uptake the lysis plasmid via electrotransformation. Generation of ghosts was enhanced by increasing the incubation temperature up to 42˚C. Cell viability of SE-2, SE-4 and ST-4 decreased ranging in log 2.7 to log 4.1 cycles after lysis induction. Moreover, SE-2 and SE-4 exhibited the earliest reduction of CFU after 3 h of incubation. Our results may provide a promising avenue for the development of Salmonella BGs vaccines.