Development of herbal and vegan oral spray and its antimicrobial activities against pathogenic bacteria, fungi and viruses

<strong>Background and Aims:</strong> Because the mouth and throat are the most important entrances of the body for several pathogens, using the nasal and oral antisepsis would be beneficial to fight with upper respiratory tract infections. In this study, a completely natural and vegan/herbal oral spray was developed and formulated, and its antimicrobial activities were tested against important mouth and upper respiratory tract pathogens. <strong>Methods: </strong>The minimum inhibitory concentrations (MIC), time-kill curves (TKC), antiviral activities, and cytotoxic activities (against A549 and VERO cell lines), of the formulated oral spray, the active ingredient mixture, and/or the active substances individually, were determined against group-A beta haemolytic Streptococcus (GABHS), Streptococcus pyogenes ATCC 19615, Staphylococcus aureus ATCC 29213, Klebsiella pneumoniae ATCC 4352, the yeast Candida albicans ATCC 10231, and Parainfluenza virus type-2. <strong>Results:</strong> The MIC values of the studied active herbal substances individually ranged from 0.4%-25%, while those for the spray formulation were 0.4-3%. TKC analysis showed that the oral spray has strong microbiocidal activities (≥3-Log₁₀) against all studied bacteria and yeast. Against parainfluenza virus type-2, the oral spray and the active ingredient mixture had strong antiviral activity (78% and 68%, respectively), without any cytotoxic effect. <strong>Conclusion:</strong> According to our findings, the formulated and developed oral spray has several advantages such as having antiviral, antibacterial, and antifungal activities, being completely natural and vegan, free of chemical antiseptics, creating a moisturising and soothing protective layer with its barrier effect, and the ease of use of the spray form.