Title : Spirulina platensis enriched with Silver Nanoparticles: A Novel Bioalternative against Antibiotic Resistance in Tunisian Urogenital Mycoplasma Strains
Abstract:
The emergence of antibioresistance in bacteria has become increasingly widespread, making it one of the major health problems of the century. As with many bacteria, in mycoplasmas, particularly urogenital mycoplasmas, the emergence of resistant strains in the Tunisian population has been the subject of several studies. These latter revealed an alarming resistance and multiresistance among Mycoplasma hominis and Ureaplasma spp. strains. Hence the need to monitor the evolution of this threat and to explore potential alternatives for fighting and containing its spread. spirulina, a cyanobacterium rich in bioactive compounds, is gaining attention as a natural alternative to combat antibioresistance. Its ability to produce diverse metabolites and biosynthesize metal nanoparticles, such as silver nanoparticles, provides a promising antibacterial potential. In this context, as an alternative to conventional antibiotics, we intend to test the activity of Spirulina platensis on resistant urogenital mycoplasmas strains and to assess its enhancement following silver nanoparticles enrichment. Urogenital mycoplasmas clinical strains were isolated from Tunisian patients suffering from infertility and urogenital infections. After they were cultured, their antibacterial susceptibility was determined against tetracyclines, macrolides and fluoroquinolones. The activity of spirulina enriched with silver nanoparticles (SpAg) was assessed using the microdilution method and the minimal inhibitory concentration ascertainment. Two batches of spirulina with different concentrations of silver nanoparticles (5755 ppm and 22400 ppm) in addition of the unprocessed spirulina were tested. Among the tested isolates, M. hominis strains were resistant to moxifloxacin, ofloxacin and tetracycline with rates of 8%, 16% and 20%, respectively. As for Ureaplasma spp., a high rate of resistance was observed within the three antibiotic classes, revealing 46% of multidrug resistance cases. The treatment of mycoplasma strains with spirulina with or without silver nanoparticles showed promising results. The antimycoplasmic activity of the two SpAg batches exhibited higher levels of antibacterial activity than with the unprocessed spirulina. To date, our results highlight the efficiency of spirulina platensis combined to silver nanoparticles and support its use as an effective mean for combating antibioresistance in mycoplasmas.
