Fractionation and Characterization of Tannin Acyl Hydrolase from Aspergillus niger
AbstractWe previously produced tannin acyl hydrolase (tannase) from Aspergillus niger isolated from cacao pod. In the present study the enzyme was subjected to fractionation by ammonium sulphate followed by dialysis process. The saturation level of ammonium sulphate used was 30-80% where the best enzyme activity was obtained at the saturation level of 60%. Compared to that of crude enzyme, specific activity of tannase after dialysis was four folds. Characterization results showed that optimum activity was at 35-50 oC and pH 6. Tannase was activated by K+ and Na+ at concentration of 0.01 and 0.05 M respectively. Mg2+ was found activate tannase only at 0.01 M. Addition of metal ions like Zn2+, Cu2+, Ca2+, Mn2+ and Fe2+ inhibited the enzyme activity. Kinetics analysis of various substrates tested showed that the Km value of tannic acid and gallotannin was 0.401 and 6.611 mM respectively. Vmax value of tannic acid was 10.804 U/ml and of gallotannin was 12.406 U/ml. Based on Michaelis-Menten constant (Km), the tannase obtained in the present study was more active in hydrolysing depside bonds rather than ester bonds.
Key words: tannase, fermentation, fractionation, characterization, Aspergillus niger
HAYATI J Biosci article's license is CC-BY-NC. This license lets others distribute, remix, tweak, and build upon author's work, as long as they credit the original creation.
Authors who submit and publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal/publisher non exclusive publishing rights with the work simultaneously licensed under a https://creativecommons.org/
licenses/by-nc/4.0/Attributi on — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
- Authors can still use their work commercially
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).