Optimization of production conditions, isolation, purification, and characterization of tannase from filamentous fungi.

Abstract

Tannase-producing filamentous fungi residing alongside tannin-rich ambient in the Northwest Himalayas were isolated at laboratory conditions and further identified by 18S ribosomal RNA gene sequencing. Five most potent tannase producing strains (EI ≥ 2.0), designated Aspergillus fumigatus AN1, Fusarium redolens AN2, Penicillium crustosum AN3, Penicillium restrictum AN4, and Penicillium commune AN5, were characterized. The strain Penicillium crustosum AN3 exhibited a maximum zone dia (25.66mm ± 0.38). During solid-state fermentation, a maximal amount of tannase was attained withPenicillium crustosum AN3 usingpine needles (substrate) by adopting response surface methodology for culture parameter optimization. Gel filtration chromatography yielded 46.48% of the partially purified enzyme with 3.94-fold of tannase purification. We found two subunits in enzyme-117.76 KDa and 88.51 KDa, respectively, in the SDS-PAGE. Furthermore, the characterization of partially purified tannase revealed a maximum enzyme activity of 8.36 U/mL at 30°C using a substrate concentration (methyl gallate) of 10mM. To broaden the knowledge of crude enzyme application, dye degradation studies were subjected to extracellular crude tannase fromPenicillium crustosum AN3 where the maximumdegradation achievedat a low enzyme concentration (5ppm).