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Looking Outwards: Isolation of Cyanobacterial Released Carbohydrate Polymers and Proteins
Published on: May 27, 2019
Sequestration of Reactive Blue 4 by free and immobilized Bacillus subtilis cells and its extracellular
Arthur Raj Binupriya1, Muthuswamy Sathishkumar, Chang Sub Ku
1Department of Food Science and Technology, College of Agriculture and Life Science, Chonbuk National University, Jeonju, Republic of Korea.
Abstract:
Bacillus subtilis a gram positive bacteria and its extracellular polysaccharide were used in free form as well as immobilized form as biosorbent for sequestration of an anionic dye, Reactive Blue 4 (RB) in aqueous phase. The dye uptake enhanced with decrease in pH. Extracellular polymeric substances (EPS) and free cells were found to be better adsorbents when compared to alginate immobilized cells (IC) and EPS (IEPS). The presence of functional groups in free cells and EPS was confirmed by FT-IR analysis. Immobilization resulted in poor adsorption performance due to increase in mass transfer resistance by the polymeric matrix. High Q(max) and b values were noted in the case of free cells and free EPS in contrast to IC and IEPS. From the kinetic experiments, the adsorption system was found to be a pseudo-first-order reaction at low dye concentration. Desorption of RB was found to be 100% in 1N NaOH. However, the alginate beads were found to be unstable under high alkaline conditions of NaOH.

