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Tag: actinobacteria

Isolation of Antimicrobial Producing Actinobacteria from Soil Samples

Actinobacteria is a gram-positive that mostly found in both aquatic and terrestrial environment. This kind of bacteria  reveals a great economic importance because of its contributions in agriculture and forest soil systems. Actinobacteria is much like fungi aiding in the decomposition of organic matter from the dead organisms. Because of these, the emergence of multidrug resistant bacteria made into a novel research for bioactive compound. This particular research study investigates the antimicrobial activity of Actinobacteria isolated from the soil in Egypt.

Antimicrobial Activity of Actinobacteria

One hundred samples were collected and analyzed from the farming soil of Egypt wherein 12 isolates produces activity against tested organisms. The soil sample was grown on Actinomycetes isolation agar for identification of Actinobacteria. Using ethyl acetate extraction method the culture isolates tested against indicator organisms. Such as S. aureusBacillus cereusE. coliK. pneumoniaeP. aeruginosaS. Typhi, C. albicansA. niger and A. flavus. It is then screened for their antibacterial activity on Mueller Hinton agar using streak plate technique.


The 12 isolates exhibited broad spectrum of antimicrobial activity against the test organisms. In which the zone of inhibition ranges from 2.5-10.2 mm wherein all strain of Actinobacteria could not inhibit E.coli. But the rest exhibited zone of inhibition among the test organisms. There were four isolates also showed activity to Candida albicans, two against A.niger and two against A.flavus.


Therefore, soil samples are rich in Actinobacteria that reveals a wide spectrum as an antimicrobial agent. It is also recognized as producers of various bioactive metabolites that are vital to human and medicine. These includes as an antifungal, antitumor drugs, immunomodifiers and enzymes inhibitors. On the other hand Actinobacteria also gives importance in agriculture as an insecticides, fungicides, herbicides and growth enhancement substances. Indeed, this study indicates that Actinobacteria isolated from Egypt farms could be sources of antimicrobial bioactive substances.


Sources: Prepared by Joan Tura from Saudi Journal of Biological Sciences

Volume 25, Issue 1, January 2018, Pages 44-46