  Antibiotic resistance is a topical problem for both humans and animals and
has been the subject of special monitoring for two decades. Several recent
studies, including ours, have shown that this phenomenon is accentuated by the
transfer of certain genetic elements and cross resistance acquisition, the
latter or both resulting from the misuse of these antimicrobial drugs. A more
careful use of antimicrobials, the search for new antibacterial compounds
(including probiotics and phages) are the most recommended alternatives to
overcome this situation. However, tests for modulations of antimicrobial
activity can also play a major role. The main goal of synergy studies is to
assess whether substances with antibacterial properties can improve the
effectiveness of existing antimicrobials or give them a second life against
resistant germs. Moreover, recent studies have demonstrated the ability of
silver nanoparticles and extracts of certain plants to boost the effectiveness
of certain antibiotics. such as ampicillin, benzylpenicillin, cefazolin,
ciprofloxacin, nitrofurantoin, and kanamycin. Yet, from these studies we found
that there was a serious problem with the interpretation of the results when
using the disk method with determination of the increase in fold area. Indeed,
the use of this method firstly requires the determination of the diameter of
inhibition of the antibiotic alone; follow by the determination of the
combination of antibiotic + modulating substance (MS) or extract.....
