Introduction. We have developed a soft dosage forms (emulsion, cream-mask) with Saw Palmetto extract and Sophora Japonica tincture for androgenic alopecia (АА) local application. To ensure microbiological stability during storage pеriod preservatives were administered to the composition of these drugs. When selecting preservatives it was taken into account not only their effectiveness to wide range of microorganisms, but their ability to provide additional technological and pharmacological parameters of the emulsion and the cream-mask. That is why, potassium sorbate (thickener of carbopol gel), salicylic acid (has keratolytic properties) and their combination were chosen for investigation. Thus, the purpose of the study was the preservative choice and confirmation of its effectiveness in the medicinal cosmetic remedies intended for AA topical treatment.
Materials and methods. The effectiveness of antimicrobial preservatives was determined in vitro method according to the Ukrainian State Pharmacopoeia methodology. As the test strains there were used the following microorganisms: Staphylococcus aureus АТСС 6538Р, Escherichia coli АТСС 8739, Pseudomonas aeruginosa “Terakov”, Candida albicans АТСС 10231, Aspergillus brasiliensis АТСС 16404. Determination of the microorganisms quantity was performed every 2, 7, 14 and 28 days after contamination by the way of counting the colonies number in each Petri dish.
Results and discussion. The conducted research showed that the remedies active substances did not possess antimicrobial properties and even at a minimal level supporting their life activity. Samples with preservative potassium sorbate were resistant to fungi and to a lesser extent to the strains of S. aureus and P. aeruginosa.
Preservatives combination of potassium sorbate (0.1%) and salicylic acid (0.1%) provide stronger antibacterial and antifungal effect. After 7 days of storage, in any samples of contaminated drugs there were not revealed bacteria and fungi.
Conclusions. The experimental studies have shown that to undertake the microbiological stability of the emulsion and cream-mask it is necessary to use the antimicrobial preservative.
Potassium sorbate in concentrations of 0.2% provides the necessary preservative effect bud on the limit level. Preservative combinations of potassium sorbate and salicylic acid (1:1) — 0.2% have stronger antimicrobial properties and meets the criteria A of antimicrobial effectiveness in remedies for cutaneous application, specified in the Ukrainian State Pharmacopoeia.