A novel cellulase free alkaliphilic xylanase from alkali tolerant Penicillium citrinum: production, purification and characterization

Abstract

Aims: The enzymatic hydrolysis of xylan has potential economic and environment‐friendly applications. Therefore, attention is focused here on the discovery of new extremophilic xylanase in order to meet the requirements of industry. Methods and Results: An extracellular xylanase was purified from the culture filtrate of P. citrinum grown on wheat bran bed in solid substrate fermentation. Single step purification was achieved using hydrophobic interaction chromatography. The purified enzyme showed a single band on SDS‐PAGE with an apparent molecular weight of c. 25 kDa and pI of 3·6. Stimulation of the activity by β mercaptoethanol, dithiotheritol (DTT) and cysteine was observed. Moderately thermostable xylanase showed optimum activity at 50°C at pH 8·5. Conclusion: Xylanase purified from P. citrinum was alkaliphilic and moderately thermostable in nature. Significance and Impact of the Study: The present work reports for the first time the purification and characterization of a novel endoglucanase free alkaliphilic xylanase from the alkali tolerant fungus Penicillium citrinum. The alkaliphilicity and moderate thermostability of this xylanase may have potential implications in paper and pulp industries.

Fungal Biodegradation of Agro-Industrial Waste

“…The peaks were used for subsequent characterization and properties of enzymes. These purification techniques are comparable to those reported by [108,109,110,111] using sephadex G-100; sephadex G-150; sephadex G -50 and G -200 and superdex-200 HR respectively. …”

Novel cellulases from an extremophilic filamentous fungi Penicillium citrinum: production and characterization

“…So to obtain high-titre extremophilic cellulase, alkali tolerant Penicillium citrinum MTCC 6489 was isolated from soil. Previous reports showed that P. citrinum MTCC 6489 produce high extent of alkaliphilic xylanase [10,11]. This paper reports for the first time about the production and properties of cellulases from the same P. citrinum.…”

Newly isolated Penicillium oxalicum A592-4B secretes enzymes that degrade milled rice straw with high efficiency

“…P. janthinellum produces cellulase at an ideal rate, 28,29) and P. citrinum produces cellulase and xylanase for which neutral pH is optimum. 30,31) P. pinophilum produces 1.9 U/mL of EG in a cellulose-supplemented synthetic culture medium, and P. purpurogenum produces 24 U/mL of EG in a peptone-containing culture medium. 32) The secreted enzyme of the present strain, P. oxalicum A592-4B, is efficient in productivity and produces approximately 5 U/mL of EG in a semi-synthetic culture medium supplemented with rice straw and yeast extract.…”