Bioprocess development for β-and γ-rubromycin production: a human telomerase inhibitors, by Streptomyces sp. ADR1

Abstract

Rubromycins are important group of antibiotic produced by actinomycetes. For many years this telomerase inhibitor anticancer bioactivc compound was mainly produced by either microbes belongs to actinomycetes or by mean of chemical synthesis. In this work, we used a new thermotolerant rubromycins producer strain (Streptomyces sp. ADR!) isolated from Algerian desert. This strain was able to produce a mixture of rubromycins (β and γ), at relatively high concentrations. At first, the most suitable medium composition for production process was selected through screening of different medium used for secondary metabolites production by actinomycetes followed by complete studies on growth and production kinetics in shake flask level. At this stage, the maximal rubromycins production were 24.58 mg/L and 356 mg/L, for β-rubromycins and γ-rubromycins, respectively. After this step, cultivations were conducted in 16-L stirred tank bioreactor for further study the industrial potential of this process. The results showed that transferring the process from shake flask to bioreactor level and cultivation under non-oxygen limitation increased the volumetric production up to 27.41 mg/L, and 580.35 mg/L for β-rubromycins and γ-rubromycins, respectively.