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.

Biochemical characterization of immobilized tannase from Aspergillus awamori

“…This may be due to the possible reason that the adsorbed enzymes were rather susceptible to desorption from the carrier (Chhokar et al, 2008). (Yao et al, 2014). The immobilized enzyme prepared by ionic binding to amberlite showed highest enzyme efficiency (2.22 U g -1 carrier) and immobilization yield.…”

“…Tannase immobilization has been studied using various supports including chitosan beads (Abdel-Naby et al, 1999), polyacrylamide, calcium alginate (Yao et al, 2014), concanavalin ASepharose (Sharma et al, 2002), coacervate calcium alginate membrane , Amberlite IR 1204 (Sharma et al, 2008). However, entrapment into semi-permeable membrane capsule using sodium alginate is a cost effective common method that shows good performance in industrial applications (El-Tanash et al, 2011).…”

“…However, entrapment into semi-permeable membrane capsule using sodium alginate is a cost effective common method that shows good performance in industrial applications (El-Tanash et al, 2011). Recently Yao et al (2014) studied different supports for tannase immobilization and found that entrapment in calcium alginate beads was the best method. Therefore, in the present study, tannase from A. awamori was immobilized on various supports and the properties of immobilized tannase were compared with free enzyme.…”

“…They reported that immobilized enzyme prepared by covalent binding to chitosan showed highest activity and Yield. Previous supports for tannase immobilization includes chitosan beads(Abdel-Naby et al, 1999), polyacrylamide, calcium alginate(Yao et al, 2014), concanavalin ASepharose(Sharma et al, 2002), Amberlite IR 1204(Sharma et al, 2008), sodium alginate(El- Tanash et al, 2011) and calcium alginate…”

Tannase from Aspergillus melleus improves the antioxidant activity of green tea: purification and biochemical characterisation

“…Tannase (tannin acyl hydrolase EC 3.1.1.20) is an inducible enzyme that catalyses the hydrolysis of ester and depside bonds present in hydrolysable tannins, and the reaction's final products are glucose and galic acid (Yao et al, 2014a). Tannins are secondary metabolites found in many plants.…”