Screening for bioactive secondary metabolites in Actinomycetes isolated from soils around old buckthorn and palm trees

Abstract

Antibiotic resistance is one of the biggest public health threats increased globally in this century. This study is aimed to determine the compounds with antimicrobial activity exhibited in Actinobacteria as a source for new antibiotic to treat highly-resistant bacteria. The Actinobacteria isolated from the soil around buckthorn and palm old trees using IPS4 agar media for first screening. ISP2 agar and broth media were used for Actinobacteria identification and fermentation and secondary metabolites production respectively. Secondary metabolites screening was done using extracellular crude extract against extended spectrum beta-lactamases (ESBLs) producing Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa and beta lactam resistant Staphylococcus aureus by well diffusion method. The total number of Actinobacterial isolates was 10, most of them showed good antimicrobial activity appeared by a particularly good zone of inhibition around resistant bacteria. This finding gives a promise that Streptomyces in soil around buckthorn and palm old trees considered as a source for new antibiotics.

Keywords

• streptomyces
• esbls
• multidrug resistance
• bioactive compounds