A comparative evaluation of Juniperus species with antimicrobial magistrals

Abstract

The objective of this study was to evaluate the in vitro bioactivity of the active ingredient in selected antimicrobial magistral drug formulations and plant extracts used in folk medicine, comparatively. The active ingredients of magistrals such as; boric acid, balsam of Peru, zinc oxide, Calendula tincture, thymol, resorcinol, crystal violet were used as well as fruit or leaf extracts of Juniperus excelsa (Je), J. sabina (Js), J. foetidissima (Jf), J. communis ssp. nana (Jcsn), and J. oxycedrus spp. oxycedrus ripe (Joso) to determine the antimicrobial activity against gram positive bacteria (S. pyogenes, S. aureus, S. epidermidis, E. faecalis), gram negative bacteria (K. pneumoniae, H. influenza, P. aeruginosa, A. baumannii, E. coli), and fungi (Candida. albicans, C. tropicalis, C. parapsilosis, C. krusei) by using microdilution method. The inhibition end point of the minimum inhibition concentrations (MICs) were determined as µg mL-1. The active ingredient and plant extracts have shown antibacterial and antifungal activities with a MIC values of 1>128µgmL-1. The active ingredient crystal violet (MIC; 1 µg mL-1) as well as Je- fruit ethanol, Jf-leaf and fruit ethanol, Joso-leaf and fruit ethanol extracts (MIC; 16µg mL-1) have exhibited the highest antimicrobial activities (MIC; 16µg mL1 ). Although ingredients of magistrals seem to exert similar antifungal activity against C. albicans, C. tropicalis, and C. parapsilosis (MIC; 32µgmL-1), thymol and resorcinol were observed to be more active against C. krusei (MIC; 16µg mL1 ). Extracts were more pronounced against P. aeruginosa, A. baumannii, and S. epidermidis (MIC ranging from 16 to 32). In the mine time, the extracts showed equal antifungal activity against C. albicans and C. parapsilosis (MIC; 16µg mL-1). In our study, antimicrobial activity of the natural compounds and ingredients of selected magistrals have found to be promising with MIC values of 16-32µg mL-1. According to the results of our antimicrobial activity studies, utilization of Juniperus extracts in antimicrobial magistral formulations can be suggested.