In vitro antibacterial activity of a crude extract of Eugenia species against mollicute strains

Abstract

The need for new antimicrobials against mollicutes is constantly increasing, mainly because mollicutes are responsible for the development of several prominent diseases, including Mycoplasma arginini, M. hominis and Ureaplasma urealyticum. The last two are involved in urogenital tract infections that can lead to infertility and gestational complications. Meanwhile, M. arginini is an animal pathogen, isolated from sheep, that causes a serious respiratory disease, known as "coughing syndrome", and possibly zoonoses. The Eugenia genus belongs to the Myrtaceae family, which includes around 500 plant species with therapeutic potential. In this study, crude extracts from the leaves of E. beaurepaireana, E. brasiliensis and E. umbelliflora were obtained and tested by broth microdilution against mollicute strains. The minimal inhibitory concentration determined for the plant extracts was 1.25 mg/mL for E. beaurepaireana, 2.5 mg/mL for E. brasiliensis and 5.0 mg/mL for E. umbelliflora against three species of mollicutes. E. beaurepaireana in particular stands out as having good antimicrobial potential. Due to the serious diseases caused by these pathogens, as well as growing antibiotic resistance to conventional treatment, it is important research new antibiotic candidates derived from the Brazilian ecosystem. There exist very few studies of the pharmacological properties of the Eugenia plant genus and our report is the first to describe its antimicrobial properties against mollicutes.