## 1 Introduction  
_Staphylococcus aureus_ is responsible for many different infections of varying severity, including skin and soft tissue infection, bacteremia, endocarditis and pleurisy [1]. It is worth emphasizing that more and more scientific reports reveal increasing resistance of bacteria (including _S. aureus_) not only to antibiotics and chemotherapeutics, but also to currently available antiseptics [2]. The observed increase in bacterial resistance to known antibacterial substances poses a huge challenge to scientists and has led them them seek new solutions. An interesting way to fight against resistant strains of _S. aureus_ (e.g., in the treatment and care of infected postoperative wounds or in the eradication of bacterial carriage) may involve using an antiseptic in combination with natural products, including essential oils (EOs) and their main compounds, which, according to the available literature, are characterized by antimicrobial properties [3]. These substances often act synergistically with antiseptics and reduce doses or concentrations to effective levels which are necessary to achieve therapeutic effects [4]. The carriage of methicillin-resistant _S. aureus_ (MRSA) strains may determine the subsequent occurrence of infection (so-called autoinfection), which mainly affects patients after surgeries, including cardiac and orthopedic ones. Therefore, their eradication with the use of antibiotics (e.g., intranasal muiprocin) or antiseptics (e.g., washing the entire body with chlorhexidine) is a crucial method of preventing staphylococcal self-infections in such patients [5]. It is worth emphasizing that infections caused by the same strain whose carriage was detected before the occurrence of _S. aureus_ in the blood constitute the vast majority of staphylococcal bacteremia in carriers of this pathogen [6]. Infections of _S. aureus_ etiology also include those occurring in postoperative patients, in whom the focus of infection depends on the surgical site (so-called surgical site infection--SSI). Interestingly, the nasopharyngeal carriage of _S. aureus_ has been shown to be a significant risk factor for SSI. _S. aureus_ is considered the most common etiological factor of postoperative mediastinitis [7]. Antiseptics are widely used in medicine to prevent the transmission of microorganisms and SSI and limit the colonization of patients and medical staff. They are available in various preparations, such as liquids with atomizers, gels for topical use, body washes or irrigation fluids. To ensure safety, these preparations should be highly effective and have low toxicity. A number of different preparations bear specific indications for use [8]. Povidone-iodine (PVP-I) is an aqueous solution of free iodine and polyvinylpyrrolidone [9]. PVP-I exhibits killing properties against Gram-positive (including MRSA strains) and Gram-negative bacteria, fungi, spores and viruses [10]. The bactericidal effect of PVP-I is achieved by adding free iodine to the amino group in amino acid and nucleic acid compounds. The thiol group in cysteine, which is an important sulfur amino acid, is also modified. Changes are also observed in the phenolic groups of amino acids and structures of fatty acids. In consequence, key enzymes are inhibited and structural proteins of the bacteria are destroyed, which, in turn, leads to the death of the microorganism. So far, no increasing resistance to PVP-I has been reported [11]. This compound is considered safe and is routinely used as an antiseptic in medical facilities (e.g., in the preparation called Braunol). Chlorhexidine digluconate (CHG) is a mixture of chlorhexidine and D-gluconic acid. Chlorhexidine, demonstrating antiseptic properties, is the main substance contained in the preparation. However, D-gluconic acid, which acts as a buffer, also exhibits antiseptic properties [12]. CHG is a positively charged molecule.