Biosynthesis of tannin acyl hydrolase from tannin-rich forest residue under different fermentation conditions

Caesalpinia digyna, a tannin-rich forest residue, was used as substrate for production of tannase and gallic acid. Media engineering was carried out u nder solid-state fermentation, submerged fermentation and modified solid st ate fermentation conditions for optimum synthesis of tannase and gallic aci d (based on 58% tannin content in the raw material). Tannase vis-a-vis gall ic acid recovery under modified solid-state fermentation condition was maxi mum. Conversions of tannin to gallic acid under solid-state fermentation, s ubmerged fermentation and modified solid-state fermentation conditions were 30.5%, 27.5% and 90.9%, respectively.