PRODUCTION OF TANNASE THROUGH SUBMERGED FERMENTATION OF TANNIN-CONTAINING CASHEW HUSK BY ASPERGILLUS ORYZAE

Tannins are water soluble polyphenolic compounds found in plants as secondary metabolites which can be grouped as hydrolysable and non-hydrolysable tannins. The presence of these substances in the husk of cashew was initially extracted and their crude extract was used separately as a substrate for the production of tannase through submerged fermentation by Aspergillus oryzae. Tannase production as well as the biodegradation of the substrate reached maximum within 24 to 36 h against crude tannin extract obtained from Anacardium occidentale. Tannse production was higher by almost two fold in the presence of crude tannin compared to pure tannic acid used as a substrate. It seems that the industrial production of tannase, using husk extract of Anacardium occidentale can be a very simple and suitable alternative to presently used procedures. This method appears to be much more accurate than those reported earlier.