Chemostat production of pediocin SM-1 by Pediococcus pentosaceus Mees 1934.

Abstract

Production of the bacteriocin pediocin SM-1 by Pediococcus pentosaceus Mees 1934 was investigated in pH-controlled batch and chemostat cultures using a complex medium containing glucose, sucrose or fructose. In chemostat cultures operated at 150 rpm, 30°C, 60% dissolved oxygen tension, pH 6.5, and D = 0.148 h(-1) , the pediocin titer reached 185 AU/mL representing an increase of 32% compared with batch cultures in which glucose was used as the carbon source. Pediocin biosynthesis was markedly affected by the growth rate of the producer microorganism. For all carbon sources tested, pediocin production appeared to take place only at dilution rates lower than μmax . However, only glucose supported production at the very low dilution rate of 0.05 h(-1) indicating a direct regulation of pediocin biosynthesis by the carbon source. Glucose supported higher biomass productivity and higher pediocin titers and yields compared with the other sugars used.