Tannin Acyl Hydrolase (E.C. 3.1.1.20) is commonly referred to as tannase. Teighem
accidentally discovered this unique enzyme in 1867 (Teighem, 1867). He reported the
formation of gallic acid when two fungal species were exposed to an aqueous solution
of tannins. The fungal species were later identified as Penicillium glaucum and
Aspergillus niger (Lekha & Lonsane, 1997).
Tannase is responsible for the hydrolysis of ester and depside linkages in tannins to
liberate gallic acid and glucose. This was a very interesting observation due to the
usual complexation of proteins with tannic acid and naturally occurring tannins to
form water insoluble complexes that inactivates enzymes (Haworth et al., 1985).
Tannins have since been shown to be the natural substrate for the tannase enzyme.
The enzyme also attacks gallic acid methyl esters, but it possesses high specificity
towards the acyl moiety of the substrate.
It has been known that certain moulds and fungi belonging to the species Aspergillus
and Penicillium produce the enzyme (Rajakumar & Nandy, 1983). According to the
work done by Yamada et al., (1968) the enzyme was mainly found intracellularly
although the culture broth also contained the enzyme. Aspergillus niger, A. flavus and
A. oryzae were found to be the best tannase producers on tannic acid as a sole source
of carbon. From these growth studies it became evident that the tannase enzyme was
an inducible enzyme (Gupta et al., 1997, Jean et al., 1981 and Mattiason & Kaul,
1994).
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ufs/oai:etd.uovs.ac.za:etd-09202002-074620 |
| Date | 20 September 2002 |
| Creators | Albertse, Ewald Hendrik |
| Contributors | Dr E van Heerden, Dr. J Albertyn, Prof. D Litthauer |
| Publisher | University of the Free State |
| Source Sets | South African National ETD Portal |
| Language | en-uk |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://lourie.uovs.ac.za//theses/available/etd-09202002-074620/restricted/ |
| Rights | mixed, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to University Free State or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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