Tannases are a family of esterases that catalyze the hydrolysis of ester and depside bonds of hydrolyzable tannins to release small compounds such as glucose.In this work,tannase production from Bacillus cereus strain...Tannases are a family of esterases that catalyze the hydrolysis of ester and depside bonds of hydrolyzable tannins to release small compounds such as glucose.In this work,tannase production from Bacillus cereus strain KMS3-1 was purified and characterized.The standard methods,such as ammonium sulfate precipitation followed by gel filtration chromatography,were used to purify the enzyme tannase from KMS3-1.With 40%enzyme recovery,the purification process yielded a 1.93-fold increase in specific activity.Analysis using SDS-PAGE confirmed a molecular weight of about 40 kDa.Circular dichroism analysis revealed the secondary structure compositionα-helix(12.03%),indicating a dominant role ofβ-turns(38.4%).A pH of 6.0 and a temperature between 50 and 60℃were ideal for enzyme activity.Tannic acid has an enzyme Km value of 3.0×10^(-3) M and a Vmax of 4.45 U/mL.Surfactants,metal ions,organic solvents,and inhibitors significantly influence the enzyme activity.Cyto-toxicity assays revealed the non-toxic nature of the purified enzyme on Vero cells and rat animal models.These results explore and contribute to a better understanding of tannase enzyme properties and their potential ap-plications in the food and beverage industries.展开更多
基金the Researchers Supporting Project(no.RSP2024R191),King Saud University,Riyadh,Saudi Arabia.
文摘Tannases are a family of esterases that catalyze the hydrolysis of ester and depside bonds of hydrolyzable tannins to release small compounds such as glucose.In this work,tannase production from Bacillus cereus strain KMS3-1 was purified and characterized.The standard methods,such as ammonium sulfate precipitation followed by gel filtration chromatography,were used to purify the enzyme tannase from KMS3-1.With 40%enzyme recovery,the purification process yielded a 1.93-fold increase in specific activity.Analysis using SDS-PAGE confirmed a molecular weight of about 40 kDa.Circular dichroism analysis revealed the secondary structure compositionα-helix(12.03%),indicating a dominant role ofβ-turns(38.4%).A pH of 6.0 and a temperature between 50 and 60℃were ideal for enzyme activity.Tannic acid has an enzyme Km value of 3.0×10^(-3) M and a Vmax of 4.45 U/mL.Surfactants,metal ions,organic solvents,and inhibitors significantly influence the enzyme activity.Cyto-toxicity assays revealed the non-toxic nature of the purified enzyme on Vero cells and rat animal models.These results explore and contribute to a better understanding of tannase enzyme properties and their potential ap-plications in the food and beverage industries.
