Evaluation of the antimicrobial ac- tivity of the extracts of oregano and marsh cinquefoil against gram-positive and gram-negative bacteria

Abstract

One of the most critical problems in animal husbandry and public health is antibiotic resistance, associated with the widespread use of antibiotic drugs. As a result, pathogenic microorganisms develop antibiotic resistance, which creates the need to either increase their dosage or replace them with other medications. Phytobiotics are a promising alternative to antibiotic drugs. Phytobiotics are active substances of medicinal plants that exhibit antimicrobial properties against pathogenic microorganisms. The primary sources of antimicrobial activity of phytobiotics are phenolic and polyphenolic compounds. The research aimed to study the antimicrobial activity of oregano (O) extracts and marsh cinquefoil (MC). Alcohol extracts (AE) were prepared from dry raw materials by water-alcohol extraction, and then alcohol-free extracts (AFE) were obtained using vacuum distillation. The content of polyphenolic compounds was studied in the obtained extracts, and the hole method against pathogens such as Staphylococcus aureus, Escherichia coli and Salmonella enterica evaluated their antimicrobial properties. The results showed that in O AFE, the content of polyphenolic compounds was 1.487 mg/ml, in O AE 1.166 mg/ml, in MC AFE 1.349 mg/ml, and MC AE 1.074 mg/ml. All studied extracts showed antimicrobial activity against Staphylococcus aureus. The most significant zones of suppression (1.86 cm) were formed around the wells with O AFE, which were significantly (P<0.01) larger than in the samples with O AE. About gram-negative cultures, zones of suppression were found only in alcoholic extracts, which is most likely a demonstration of the antibacterial activity of ethanol.