Approche théorique sur l’activité antimicrobienne des actinobactéries isolés de différents écosystèmes

Abstract

Historically, actinomycetes have received much attention due to their ability to produce a variety of secondary metabolites of significant biotechnological value. On the other hand, the purpose of this work was part of the research and investigation of actinomycetes capable of synthesizing antibacterial substances , Our choice fell on the bibliographic study of actinobacteria, because they constitute a natural and attractive source of various bioactive molecules such as antibiotics, antifungal and antioxidants. 15 scientific articles were analyzed which relate to the isolation of actinomycetes in different environmental settings. We have spoken in this work of several essential points, starting with the nature of the samples, and the selective isolation approaches of actinobacteria (selective inhibition and nutritional selection), the methods of screening the antimicrobial activities of actinobacteria and ending with a discussion of the most commonly used fermentation and extraction techniques. It has been found that casein agar medium with starch is the most used in the isolation of actinobacteria. Of which starch represents the most used carbon source in selective isolation media with 23%, the same for casein which occupies 29% of the nitrogen sources used. The NaCl concentrations used vary depending on the physicochemical conditions of the sample and the genus isolated. The cross-streak technique gave a higher percentage of active isolates for the evaluation of antimicrobial activity