Details

Autor(en) / Beteiligte

• Yang, J.‐K.
• Chen, Q.‐C.
• Zhou, B.
• Wang, X.‐J.
• Liu, S.‐Q.

Titel

Manno‐oligosaccharide preparation by the hydrolysis of konjac flour with a thermostable endo‐mannanase from Talaromyces cellulolyticus

Ist Teil von

• Journal of applied microbiology, 2019-08, Vol.127 (2), p.520-532

Ort / Verlag

England: Oxford University Press

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Aims A thermostable endo‐mannanase from the fungus Talaromyces cellulolyticus was identified to facilitate manno‐oligosaccharide preparation from Konjac (Amorphophallus konjac) flour. Methods and Results A putative endo‐1,4‐β‐mannanase from the T. cellulolyticus was obtained and efficiently expressed by improving its gene dosage in the genome of the host. After cultivation in a bench‐top bioreactor for about 120 h, the protein content and enzyme activity of mannanase increased to 3·4 g l−1 and 17 500 U ml−1 respectively. Enzymatic characterization showed that this enzyme has an optimal temperature of 80°C, optimal pH of 5·0. Under the optimized hydrolysis conditions of pH 5·0, 70°C, and an enzyme concentration of 200 U l−1 solution, this enzyme could efficiently hydrolyse 0·5% konjac flour into manno‐oligosaccharides (MOSs) with the degree of polymerization range from 3 to 7. The possible mechanism by which the enzyme produced MOSs was also discussed. Conclusion Talaromyces cellulolyticus endo‐mannanase is thermostable and has a broad pH range adaptability. Method of improving the dosage of mannanase gene in the genome could realized its high‐level impression. This enzyme could efficiently hydrolyse konjac flour into manno‐oligosaccharide products. Significance and Impact of the Study This study has enriched endo‐mannanase resources, facilitated its bulk production and provided a strong reference for its application in manno‐oligosaccharide preparation from the natural glucomannan of konjac flour.