title: Immobilization of cellulase from newly isolated strain Bacillus subtilis TD6 using calcium alginate as a support material.
abstract: Bacillus subtilis TD6 was isolated from Takifugu rubripes, also known as puffer fish. Cellulase from this strain was partially purified by ammonium sulphate precipitation up to 80% saturation, entrapped in calcium alginate beads, and finally characterized using CMC as the substrate. For optimization, various parameters were observed, including pH maximum, temperature maximum, sodium alginate, and calcium chloride concentration. pH maximum of the enzyme showed no changes before and after immobilization and remained stable at 6.0. The temperature maximum showed a slight increase to 60 °C. Two percent sodium alginate and a 0.15 M calcium chloride solution were the optimum conditions for acquisition of enzyme with greater stability. K (m) and V (max) values for the immobilized enzyme were slightly increased, compared with those of free enzyme, 2.9 mg/ml and 32.1 μmol/min/mL, respectively. As the purpose of immobilization, reusability and storage stability of the enzyme were also observed. Immobilized enzyme retained its activity for a longer period of time and can be reused up to four times. The storage stability of entrapped cellulase at 4 °C was found to be up to 12 days, while at 30 °C, the enzyme lost its activity within 3 days.
authors.affiliation: Interdisciplinary Program of Graduate School for Bioenergy and Biomaterials, Chonnam National University, Gwangju, 500-757, South Korea.
authors.forename: Dian
authors.initials: D
authors.lastname: Andriani
authors.forename: Changshin
authors.initials: C
authors.lastname: Sunwoo
authors.forename: Hwa-Won
authors.initials: HW
authors.lastname: Ryu
authors.forename: Bambang
authors.initials: B
authors.lastname: Prasetya
authors.forename: Don-Hee
authors.initials: DH
authors.lastname: Park
mesh_terms: D000464:Alginates / Q000737:chemistry*; D001412:Bacillus subtilis / Q000145:classification / Q000201:enzymology*; D002480:Cellulase / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D011485:Protein Binding
chemical_list: D000464:Alginates; D004800:Enzymes, Immobilized; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D002480:Cellulase