Abstract:

Under different conditions, effects of mineral powder containing potassium on  the exo-polysaccharides  (EPS) secreted
by Bacillus mucilaginosus were studied  to  further explain  the reciprocity between bacteria and potassium-baring minerals. In  the
research, B. mucilaginosus was cultured  in  four kinds of media  to analyze and compare  their EPS production. Results showed  that
bacteria secreted the highest output of both proteins and EPS in the culture with potassium-bearing minerals, but without potassium
ion. While  in  the medium with potassium  ion,  the yielded EPS were  lower. However,  in  the medium without potassium beaing
mineral powder and with or without potassium  ion,  the production of both proteins and EPS was proved  to be  the  lowest. List of
monosaccharide components of EPS secreted by B. mucilaginosus varied obviously in relation with different culture conditions. The
results demonstrated that extracellular secretion of the bacteria is closely related to the mechanism of potassium releasing.

Key words:  Bacillus mucilaginosus, exo-polysaccharides, potassium releasing mechanism, monosaccharide component