Red pigmented undecylprodigiosin produced by Streptomyces coelicolor (A3)2 is a
promising drug owing to its characteristics of antibacterial, antifungal,
immunosuppressive and anticancer activities. The culture of S. coelicolor in liquid
medium produces mainly the blue pigmented actinorhodin and only low quantities of
undecylprodigiosin. From an industrial point of view, it is necessary to find a strategy to
improve undecylprodigiosin production. The present study provides evidence that
cultivation of S. coelicolor on solid substrate resulted in a reversal in this pattern of
antibiotic production as the production of undecylprodigiosin was significantly increased
and actinorhodin was completely suppressed. Four different solid substrate (wheat bran,
soya bean ground, rice husk and ground corn) were tested for their ability to support the
maximal production of undecylprodigiosin in solid state fermentation. Wheat bran
showed the highest production of undecylprodigiosin, starting from the first day of
incubation at a moisture level of (1:1 weight: volume) and reaching its maximum of 16
mg/gds on the fourth day. In addition, we report the exploitation of the interspecies
interaction in order to enhance undecylprodigiosin production by introducing live or
dead cells of E. coli, Bacillus subtilis and Saccharomyces cerevisiae, separately, to
Streptomyces coelicolor solid substrate fermentation. Our results revealed a significant
increase in the production of undecylprodigiosin in the elicited cultures compared with
control. The maximum enhancement occurred in the culture elicited with the live cells of
B. subtilis with an increase of 2-fold compared with control.