Abstract. In recent years, microbial biofilm resistance has increased, posing significant challenges for the medical community in terms of disease treatment and for the food industry in terms of contamination and loss of shelf life. The purpose of this work is to test the antimicrobial efficacy against Gram-positive bacteria represented by the following reference strains: Streptococcus pyogenes (ATCC 19615), Staphylococcus aureus (ATCC 25923), Listeria monocytogenes (ATCC 19114), Bacillus cereus (ATCC 10876) and Clostridium perfringens (ATCC 13124), as well as the MIC evaluation of three Thuja occidentalis (TO) extracts. In accordance with ISO 20776-1:2019, the evaluation was conducted by measuring the loss of microbial mass using spectrophotometry to determine the optical density (OD). As a result of our research, we can say that to extracts, especially at the first concentration tested cause an inhibiting effect on Gram-positive bacteria. The inhibitory effect on the Gram-positive bacteria is increasing: Cl.perfringens< S. pyogenes< S. aureus < B. cereus < L. monocitogenes. The demonstrated effect of TO2 recommends it as a potential future candidate in natural products with antimicrobial activity. Our findings could allow TO2 blends in many areas, such as products for bacterial dermatological treatments and the food industry, both areas being strongly affected by the increase in antibacterial resistance to standard, commercial antimicrobial products.

Thuja occidentalis, bacteria, Gram-positive, antimicrobial.

agronomy

Presentation: poster