Screening of antimicrobial properties of ethanolic extracts from some kinds of raw materials with quinone derivatives

Abstract

This paper presents data on screening of antimicrobial properties of extracts from some kinds of raw materials (18 plants) with hydroquinone, naphtoquinone or anthraquinone derivatives. Some technological parameters of extracts (density and concentration of extraneous substances) have been determined. The most appropriate microbiological method of studying antimicrobial properties of extracts, diffusion method of “well”, has been applied; special mathematic method of comparison of antimicrobial properties of extracts vector analysis has been applied in order to study and to compare antimicrobial properties of extracts.  Indexes of antimicrobial properties of extracts have been determined: a complex index of medicinal product antimicrobial activity for quantitative estimation of antimicrobial effect - A, and square of correlation coefficient - r², which demonstrates the spectrum of antimicrobial activity of the extracts (degree of similarity to the standard). The most active extracts have been selected; they have antimicrobial properties of medium strength: from the herb of chimaphila umbellata А=2.20; the fruits of rhamnus cathartica А=2.12; the root of rubia tinctorum А=2.11; the bark of frangula alnus А=2.05; the root of rumex confertus А=2.04; the leaf of pyrola rotundifolia А=2.00; and leaf of arctostaphylos uva-ursi А=2.08 (but extract from uva-ursi did not affected on 2 strains of microorganisms r²=0.64). Low levels of antimicrobial activity have been demonstrated by the extract obtained from the leaf of urtica dioica А=0.72, r²=0.34. The mean result of the complex index of antimicrobial activity for the most of extracts from plants containing quinonederivatives is A = 1.77 (on 70% vol. ethanol at a ratio of raw material : extracting agent – 1:7 wt. : vol.) and may range from 0.68 to 2.85. The mean result of the correlation coefficient is r = 0.93 and may range from 0.59 to 0.99. The mean result of the concentration of extractives in extracts is C = 0.0386 g/g extract and may range from 0.0017 to 0.0755 g/g extract. The mean result of the extract density is ρ = 0.897 g/cm³ and may range from 0.877 to 0.917 g/cm³. It is noted antimicrobial properties of the solution of alizarin 0.1% m / m in 70% vol. ethanol, which in studies showed moderate strength antimicrobial properties: A = 1.60 and inhibited the growth of all tested strains of microorganisms r=0.99. This potentially allows to predict the antimicrobial properties of extracts from plants containing derivatives of alizarin on its concentration in them. Study data show significant antimicrobial properties of numerous kinds of raw materials that contain of hydroquinones, naphtoquinones, anthraquinones and high possibility of their use in complex phytochemical medicinal products as antimicrobial component.