Johannesört – effektiv behandling vid infektioner? : Medicinalväxten Hypericum perforatum L. och dess antibakteriella aktivitet mot multiresistenta Staphylococcus aureus 

Sammanfattning: Antibiotic resistance is a rapidly increasing and serious global problem, with infectious diseases currently being the second leading cause of death worldwide. The World Health Organization (WHO) has estimated that 700,000 people worldwide die each year as a result of antibiotic resistance, and this number is projected to rise to 10 million per year by 2050 if no action is taken. This makes it vital to find new antibacterial agents to treat infectious diseases. Staphylococcus aureus (S. aureus) is a commonly occurring gram-positive bacterium from the genus Staphylococcus. The bacterium can cause several diverse types of infectious diseases, ranging from mild to life-threatening. Hypericum perforatum L. (H. perforatum) is a plant that has been used as a medicine in various preparations for thousands of years to treat different conditions, such as e.g., wound healing. Recent investigations have shown an antibacterial effect of the plant against the bacterium S. aureus, this suggested that H. perforatum may have a possible antimicrobial effect and could potentially be used in the treatment of certain infections. The purpose of this literature review was to investigate the in vitro antibacterial effect of H. perforatum against S. aureus. For this work, database searches were conducted in PubMed and SciFinder, and four studies were finally selected that examined the in vitro effect of H. perforatum against S. aureus. Common for all the studies was that they used the broth dilution method in their analyses to obtain MIC values. The results of the literature reviews showed that H. perforatum inhibited non-resistant isolates of S. aureus with MIC values between 0.01 – 950 µg/ml. For the resistant isolates evaluated, MIC values were between 0.01 – 0.02 µg/ml. The MIC-value against the multidrug resistant strain MDR-BAA 44 was 0.01 µg/ml. The other studies had higher MIC values and less activity compared to the results reported in the first study. The first study also showed that H. perforatum had better activity against all isolates than the positive controls tetracycline and penicillin. Further studies are needed to ensure and validate the results shown in study one. Also, research should focus on further studying the effect in vivo in larger studies than previously conducted. In addition, evaluation whether a synergistic effect against resistant S. aureus can be achieved through the combination of H. perforatum together with another plant species or with an antibiotic that could provide an alternative treatment of serious infections.