Abstract
The production of extracellular polysaccharide, EPS WN9, fromPaenibacillus sp. and its suitability as a viscosity modifying admixture for cement mortar mixing were investigated. After 48 h culture in an optimized medium, cell growth and EPS production were 1,2 g/L and 4.0 g/L, respectively. By adding EPS WN9 to mortar, it was possible to prepare a homogeneous mortar without material segregation and excess air entrapment. The optimal amount of EPS addition to mortar was found to be 0.02 to 0.05%(w/w) of the cement used. Increasing the dosage of EPS WN9 from 0 to 0.05%(w/w) resulted in a setting retardation of 0.14 h to 0.8 h and an increase in the compressive strength of mortar of 10 to 20%.
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Kahng, GG., Lim, SH., Yun, HD. et al. Production of extracellular polysaccharide, EPS WN9, fromPaenibacillus sp. WN9 KCTC 8951P and its usefulness as a cement mortar admixture. Biotechnol. Bioprocess Eng. 6, 112–116 (2001). https://doi.org/10.1007/BF02931956
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DOI: https://doi.org/10.1007/BF02931956