Reaction: punicalagin = punicalin + ellagic acid (overall reaction)
(1a) punicalagin + 2 H2O = punicalin + 4,4′,5,5′,6,6′-hexahydroxydiphenic acid
(1b) 4,4′,5,5′,6,6′-hexahydroxydiphenic acid = ellagic acid + 2 H2O (spontaneous)
For diagram of reaction click here
Other name(s): ellagitannase; ellagitannin acyl esterase; EAH
Systematic name: punicalagin acyl hydrolase
Comments: The enzyme, which has been studied from the fungus Aspergillus niger, catalyses a step in the degradation of ellagitannins such as punicalagin, which are phenolic compounds occurring in pomegranates and some tropical trees. It hydrolyses ester bonds between the D-glucose core and the hexahydroxydiphenic acid groups of ellagitannins, releasing hexahydroxydiphenic acid that undergoes spontaneous lactonization to form ellagic acid. Unlike EC 3.1.1.20, tannase, it does not act on gallotannins. More recent studies suggest that the activity may be catalysed by EC 3.1.4.3, phospholipase C [5].
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Ascacio-Valdes, J.A., Buenrostro, J.J., De la Cruz, R., Sepulveda, L., Aguilera, A.F., Prado, A., Contreras, J.C., Rodriguez, R. and Aguilar, C.N. Fungal biodegradation of pomegranate ellagitannins. J. Basic Microbiol. 54 (2014) 28-34. [PMID: 23564673]
2. de la Cruz, R., Ascacio, J.A., Buenrostro, J., Sepulveda, L., Rodriguez, R., Prado-Barragan, A., Contreras, J.C., Aguilera, A. and Aguilar, C.N. Optimization of ellagitannase production by Aspergillus niger GH1 by solid-state fermentation. Prep Biochem Biotechnol 45 (2015) 617-631. [PMID: 25085574]
3. Ascacio-Valdes, J.A., Aguilera-Carbo, A.F., Buenrostro, J.J., Prado-Barragan, A., Rodriguez-Herrera, R. and Aguilar, C.N. The complete biodegradation pathway of ellagitannins by Aspergillus niger in solid-state fermentation. J. Basic Microbiol. 56 (2016) 329-336. [PMID: 26915983]
4. Buenrostro-Figueroa, J., Mireles, M., Ascacio-Valdes, J.A., Aguilera-Carbo, A., Sepulveda, L., Contreras-Esquivel, J., Rodriguez-Herrera, R. and, N. Aguilar, C. Enzymatic biotransformation of pomegranate ellagitannins: initial approach to reaction conditions. Iran. J. Biotechnol. 18 (2020) e2305. [PMID: 33542933]
5. Buenrostro-Figueroa, J., Gutierrez-Sanchez, G., Prado-Barragan, L.A., Rodriguez-Herrera, R., Aguilar-Zarate, P., Sepulveda, L., Ascacio-Valdes, J.A., Tafolla-Arellano, J.C. and Aguilar, C.N. Influence of culture conditions on ellagitannase expression and fungal ellagitannin degradation. Bioresour. Technol. 337 (2021) 125462. [PMID: 34320742]