Evaluation of a bio-engineered honey and its synthetic equivalent as novel Staphylococcus aureus biofilm-targeted topical therapies in chronic rhinosinusitis

Background - Chronic rhinosinusitis (CRS) is a common condition which affects the quality of life of millions of patients worldwide and has a significant impact on healthcare resources. Whilst Staphylococcus aureus bacterial biofilms play an important role in this disease, antimicrobial therapy is rarely effective and may promote antibiotic resistance. Thus, development of novel biofilm-targeting and antibiotic-sparing therapies is highly desirable and urgently required.

Objective - This in vitro study evaluated the antimicrobial activity of a novel synthetic honey-equivalent product which was designed to have the same reactive oxygen release profile as the engineered honey SurgihoneyRO™.

Methods - Treatment efficacy was investigated by assessment of planktonic growth, biofilm viability, thickness and biomass, using 12 CRS-related S. aureus mucosal bacterial strains.

Results - Both SurgihoneyRO™ and the synthetic honey-equivalent product inhibited growth of planktonic methicillin-resistant and -sensitive S. aureus strains, with the synthetic honey-equivalent product exhibiting a lower minimum inhibitory concentration. Treatment of established S. aureus biofilms reduced biofilm viability with 24 hour treatment resulting in a 2-log reduction in viability of biofilms formed by methicillin-resistant strains, and a 1-log reduction in biofilms formed by methicillin-sensitive strains.

Conclusions - This preliminary study shows that the synthetic honey-equivalent product provides marked antimicrobial activity against S. aureus biofilms, with the potential for development in the clinical setting as an adjunctive biofilm-targeted therapy in CRS. The ultimate aim of such a product would be to reduce the need for antibiotics, steroids and invasive surgical procedures in CRS patients, as well as improving clinical outcomes following endoscopic sinus surgery.