Some determinant factors of antimicrobial susceptibility pattern of plant extracts

Abstract

Plants are major active ingredients used for the treatment of several human diseases by traditional medicine practitioners in many regions of the world especially in developing countries. Plants are among the major feedstocks that have been researched upon for development of new antibiotics. Plants are known to contain several bioactive/ phytochemical constituents they may be responsible for their medicinal properties. Studies have shown that plant extract that are susceptible to a specific microbe may not be the same in another related study. Hence, this study reviews the factors that determine the susceptibility pattern of plant extracts. The study found that environmental factors (pH of the medium, temperature, water activity, oxygen and nutrient availability), choice of solvent, source of the organisms, biochemistry, physiology, metabolism and adaptation strategies of the microbes, plant species, biochemistry, age and parts, concentration of the plant extract and period of extraction. Hence there is the need for research to consider these determinant factors during antimicrobial susceptibility studies.