In vitro evaluation of the antimicrobial activity of Theranekron® alone and in combination with antibiotics

Antibiotic resistance continues to be one of the reasons that necessitates the development of new drugs. As a result of a lack of attention to rational antibiotic use, bacteria constantly develop new mechanisms and defense systems to survive. Nowadays, rather than developing new antibiotics, we are testing supplements to overcome potential resistance to existing drugs. In our study, we investigated the antibacterial activity of Theranekron®, an alcoholic extract of Tarantula cubensis, against standard bacterial strains, both alone and in combination with various antibiotics. We used the disk diffusion method for this evaluation. Theranekron® was tested alone and in combination with antibiotics against strains of S. aureus (ATCC 29213), E. faecalis (ATCC 29212), E. coli (ATCC 25922), and P. aeruginosa (ATCC 27853). According to the analysis results, Theranekron® showed no significant difference when used alone or with antibiotics. There were no differences in zone diameters in either application. No synergistic effects (≥2 mm) or inhibition were observed with any antibiotic-Theranekron® combination. The results obtained indicated that Theranekron® neither enhanced nor inhibited antibiotic efficacy. However, because it did not interfere with antibiotic activity, it can be considered a safe supplementary biological agent. Given Theranekron®'s anti-inflammatory and immunomodulatory effects, it may be used as a complementary agent rather than an antibacterial compound. Further studies using MIC, MBC, and synergy analyses are needed to more comprehensively elucidate antimicrobial effects.