Production and immobilization of β-glucanase from Aspergillus niger with its applications in bioethanol production and biocontrol of phytopathogenic fungi

• Published in: Scientific reports 2021-10, Vol.11 (1), p.21000-21000, Article 21000
• Main Authors: El-Shora, Hamed M., El-Sharkawy, Reyad M., Khateb, Aiah M., Darwish, Doaa B.
• Format: Article
• Language: English
• Subjects: 631/326; 631/61; Ammonium; Ammonium nitrate; Ammonium sulfate; Antifungal Agents; Aspergillus niger; Aspergillus niger - classification; Aspergillus niger - enzymology; Aspergillus niger - genetics; Biofuels; Biological control; Biological Control Agents; Biotechnology; Carbon sources; Catalysis; Cellulose; Chitosan; Enzymes; Enzymes, Immobilized; Ethanol; Ethanol - metabolism; Fermentation; Glycoside Hydrolases - biosynthesis; Glycoside Hydrolases - chemistry; Glycoside Hydrolases - genetics; Glycoside Hydrolases - isolation & purification; Humanities and Social Sciences; Immobilization; Lignocellulose; Microbial Sensitivity Tests; multidisciplinary; Phylogeny; Phytopathogenic fungi; Protein folding; Science; Science (multidisciplinary); Thermal stability
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-00237-2

β-Glucanase has received great attention in recent years regarding their potential biotechnological applications and antifungal activities. Herein, the specific objectives of the present study were to purify, characterize and immobilize β-glucanase from Aspergillus niger using covalent binding and cross linking techniques. The evaluation of β-glucanase in hydrolysis of different lignocellulosic wastes with subsequent bioethanol production and its capability in biocontrol of pathogenic fungi was investigated. Upon nutritional bioprocessing, β-glucanase production from A. niger EG-RE (MW390925.1) preferred ammonium nitrate and CMC as the best nitrogen and carbon sources, respectively. The soluble enzyme was purified by (NH 4 ) 2 SO 4 , DEAE-Cellulose and Sephadex G 200 with 10.33-fold and specific activity of 379.1 U/mg protein. Tyrosyl, sulfhydryl, tryptophanyl and arginyl were essential residues for enzyme catalysis. The purified β-glucanase was immobilized on carrageenan and chitosan with appreciable yield. However, the cross-linked enzyme exhibited superior activity along with remarkable improved thermostability and operational stability. Remarkably, the application of the above biocatalyst proved to be a promising candidate in liberating the associate lignocellulosic reducing sugars, which was utilized for ethanol production by Saccharomyces cerevisiae . The purified β-glucanase revealed an inhibitory effect on the growth of two tested phytopathogens Fusarium oxysporum and Penicillium digitatum .