Evaluating the effect of Inula viscosa and Prunus dulcis leaf extracts on gram-negative multi-drug resistant microbes

Abstract

Antimicrobial resistance (AMR) is a global life-threatening health concern, and it is worsening progressively with the minimal resolutions developed to prevent its further dissemination. AMR is a consequence of multiple public health malpractices, starting with the random use of antimicrobials to the weakness of antimicrobial stewardship guidelines and reinforcement. Bacteria expressing antimicrobial resistance to several drugs are referred to as multi-drug resistant organisms (MDROs). One alternative therapeutic pathway is the use of diverse plant phytochemicals which reflect promising results in treating infections and limiting bacterial resistance. Inula viscosa and Prunus dulcis leaves were revealed to have potential antimicrobial and antiproliferation effects. In this study, the leaves of Inula viscosa and Prunus dulcis were extracted and fractionated. Their potential antimicrobial effects were evaluated by Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC). The MBC of Inula viscosa ethanol and ethyl acetate extracts was detected at 320µg/µl in 45 and 35 strains respectively. The MIC varied between 320 & 160 µg/µl in 57 strains for the ethanol extract and in 50 strains for the ethyl acetate extract. As for the Prunus Dulcis, the MBC of itsethanol extract varied between 80 & 320 µg/µl and the MIC varied between 40 & 160 µg/µl in 59 strains. The MBC of ethyl acetate extract ranged between 160 & 320 µg/µl whereas the MIC values were between 80 & 320 µg/µl in 54 strains. Moreover, the MIC of the dichloromethane and aqueous extracts of Prunus dulcis varied between 160 & 320 µg/µl in 52 and 46 strains respectively, whereas the MBC was detected at 320 µg/µl in 40 and 35 strains respectively.The outcomes of this study verified the efficacy of the two plants, Inula viscosa and Prunus dulcis, in combating the resistance of ESBL (Extended Spectrum Beta-Lactamases) and/or CRE (Carbapenem-Resistant Enterobacterales) bacteria strains including E. coli, K. pneumoniae, A. baumannii, P. mirabilis, P. aeruginosa, and E. cloacae.