Journal of Pure and Applied MicrobiologyVol. 2 No. 1

Characterization of Extracellular Tannin Acyl Hydrolase and Gallic Acid Produced on Pomegranate Rind (Punica granatum) under Submerged Fermentation by an Aspergillus niger Isolate

Anita Srivastava and Rita Kar*

Department of Biochemical Engineering and Food Technology, Harcourt Butler Technological Institute, Kanpur - 208 002, India.

Received on 12 February 2008 and accepted on 20 March 2008

 

ABSTRACT

An isolated Aspergillus niger strain (ITCC 6514.07) was found to utilize pomegranate rind (PR) as substrate in submerged fermentation (SmF) most efficiently compared to other tannin rich agro residues tested for the production of extracellular tannin acyl hydrolase (E.C.3.1.1.20) and gallic acid. Maximum enzyme production took place at 37C, pH 5.0 with 4% (w/v) PR and mineral salt solution (MSS) after 72 h. The enzyme production was stimulated 3.3 fold by the addition of 1% tannic acid. The optimum temperature and pH of the partially purified enzyme were found to be 35C and 6.2 respectively. The Km value of the enzyme produced on PR as substrate were found to be 0.012 mM. The nature of the experimental data permitted excellent polynomial fit on the basis of which, a master equation corresponding to the isolated strain was derived for estimation of enzyme activity for any set of values of incubation time, substrate concentration, inoculum size, temperature and pH within the indicated range.

Keywords : Extracellular, Tannase, Gallic acid, Pomegranate rind, Aspergillus niger, Submerged fermentation.