title: Immobilization and characterization of tannase from a metagenomic library and its use for removal of tannins from green tea infusion.
abstract: Tannase (Tan410) from a soil metagenomic library was immobilized on different supports, including mesoporous silica SBA-15, chitosan, calcium alginate, and amberlite IRC 50. Entrapment in calcium alginate beads was comparatively found to be the best method and was further characterized. The optimum pH of the immobilized Tan410 was shifted toward neutrality compared with the free enzyme (from pH 6.4 to pH 7.0). The optimum temperature was determined to be 45°C for the immobilized enzyme and 30°C for the free enzyme, respectively. The immobilized enzyme had no loss of activity after 10 cycles, and retained more than 90% of its original activity after storage for 30 days. After immobilization, the enzyme activity was only slightly affected by Hg(2+), which completely inhibited the activity of the free enzyme. The immobilized tannase was used to remove 80% of tannins from a green tea infusion on the first treatment. The beads were used for six successive runs resulting in overall hydrolysis of 56% of the tannins.
authors.affiliation: Institute of Agricultural Applied Microbiology, Jiangxi Academy of Agricultural Sciences, Nanchang, 330200, P. R. China, School of life science, Sun Yat-sen University, Guangzhou, 510275, P. R. China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yao
authors.forename: Qinglong
authors.initials: Q
authors.lastname: Chen
authors.forename: Guoxiang
authors.initials: G
authors.lastname: Zhong
authors.forename: Wen
authors.initials: W
authors.lastname: Cao
authors.forename: An
authors.initials: A
authors.lastname: Yu
authors.forename: Yuhuan
authors.initials: Y
authors.lastname: Liu
mesh_terms: D001711:Biotransformation; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D015723:Gene Library; D006863:Hydrogen-Ion Concentration; D008628:Mercury / Q000378:metabolism; D054892:Metagenome; D008863:Microspheres; D012988:Soil Microbiology; D013634:Tannins / Q000378:metabolism*; D013662:Tea / Q000737:chemistry*; D013696:Temperature
chemical_list: D004791:Enzyme Inhibitors; D004800:Enzymes, Immobilized; D013634:Tannins; D013662:Tea; D002265:Carboxylic Ester Hydrolases; C022711:tannase; D008628:Mercury