Anti-microbial potential of medical plant extracts (Sinupret®) regarding sinusitis

Introduction Sinusitis is a common disease in public. About 85–90% of anti-microbial drugs are used in the community; up to 80% are used to treat respiratory tract infections. Antibiotics are getting limited in the case of bacterial resistance. Plants are known to be active against many infectious microbials and are widely used, with high evidence of safety and efficacy due to clinical day-to-day experience. Therefore it seems very interesting to study which effects phytomedical extracts induce in respiratory cells and which effects they demonstrate against relevant bacterials. Therefore it is interesting whether or not plant extracts induce activity in the first- and second-line defense of nasal mucosa. We addressed our interest to the capabilities of these substances in influencing in either human anti-microbial activity in nasal mucosa or direct anti-microbial activity in vitro. The anti-microbial activities of plant extracts were determined by in vitro bioassays using agar diffusion method. The minimal bactericidal concentration (MBC) and lethal dose, LD90/50, were calculated for gram-positive and -negative bacterial standard strains. Bacteria strains were selected according to their relevance on upper airway infection. We could find out that Sinupret ® either induces human anti-microbial peptides or has direct anti-microbial activity against some of the bacteria. This has been shown concerning MBC, LD90, and LD50. Conclusion Phytomedical extracts revealed distinct anti-bacterial activities. The astonishing, hitherto unknown, anti-bacterial activities of the commercially phytochemical and its extracts gave some promising clues on the anti-infective efficacy of the drug observed in clinical experience and this encourages us to elucidate the anti-microbial efficacy of phytochemical drugs.