Use of Cross-Streak Method to Determine Antimicrobial Activity

Abstract

Antimicrobial susceptibility testing can be used for prediction of therapeutic results, epidemiology and drug discovery. Microbial infections are an important problem which have developed resistance towards antimicrobial agents. Otherwise, efficacy of these agents is considerable with treatment failures associated with multidrug-resistant bacteria and it has become a global concern to public health. Therefore, explore the new antimicrobial agents and widely use of antimicrobial susceptibility need to be developed. There are many techniques for the determination of antimicrobial activity. Many of these techniques, which are applied to inhibit sensitive microorganisms, are based on diffusion-related methods in the solid or semi-solid production environment. Cross-streak among these techniques is an easy technique that allows for relatively rapid screening of cultures in research for the discovery of the new antibiotics. However, the biggest disadvantage of the Cross-streak test is the difficulty in obtaining quantitative data. Because the edges of the inhibition zone are usually very fuzzy and unclear. Some antimicrobial susceptibility testing techniques were standardized by Clinical Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) to determine the striking steps in this area. This testing procedure requires the use of specific test conditions and methods. In addition, the medium, incubation conditions and time are among these requirements. It is important to understand and develop the Cross-streak method from the currently used activity determination methods.