title: Preparation of chitooligosaccharides from fungal waste mycelium by recombinant chitinase.
abstract: This study aimed to develop an enzymatic method for conversion of chitin from fungal waste mycelia to chitooligosaccharides. The recombinant chitinase LlChi18A from Lactococcus lactis was over-expressed by Escherichia coli BL21 (DE3) and purified by affinity chromatography. The enzymatic properties of the purified enzyme were studied by chitin oligosaccharides. Waste mycelium was pre-treated by alkaline. The optimal conditions for hydrolysis of fungal chitin by recombinant chitinase were determined by Schales method. HPLC/ESI-MS was used to determine the content of N-acetylglucosamine and chitooligosaccharides after hydrolysis. The level of reducing sugar released from pretreated mycelium by chitinase increased with the reaction time during 6 days. The main product in the hydrolysates was N,N'-diacetylchitobiose. After hydrolysis by chitinase for 5 d, the yield of N,N'-diacetylchitobiose from waste mycelium was around 10% with estimated purity of around 70%. Combination of chitinase and snailase remarkably increased the yield to 24% with purity of 78%. Fungal mycelium which contains chitin is a new potential source for obtaining food grade chitooligosaccharides.
authors.affiliation: College of Bioengineering, Faculty of Light Industry, Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Hubei University of Technology, Wuhan, Hubei 430068, China.
authors.forename: Mengyuan
authors.initials: M
authors.lastname: Lv
authors.affiliation: College of Bioengineering, Faculty of Light Industry, Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Hubei University of Technology, Wuhan, Hubei 430068, China; Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-10 Agriculture/Forestry Centre, Edmonton, Alberta T6E 2P5, Canada. Electronic address: huying@mail.hbut.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-10 Agriculture/Forestry Centre, Edmonton, Alberta T6E 2P5, Canada; School of Food and Pharmaceutical Engineering, Hubei University of Technology, Wuhan 430068, China.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Gänzle
authors.affiliation: College of Bioengineering, Faculty of Light Industry, Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Hubei University of Technology, Wuhan, Hubei 430068, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Lin
authors.affiliation: College of Bioengineering, Faculty of Light Industry, Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Hubei University of Technology, Wuhan, Hubei 430068, China.
authors.forename: Changgao
authors.initials: C
authors.lastname: Wang
authors.affiliation: College of Bioengineering, Faculty of Light Industry, Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Hubei University of Technology, Wuhan, Hubei 430068, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Cai
mesh_terms: D001234:Aspergillus niger / Q000737:chemistry*; D002686:Chitin / Q000031:analogs & derivatives* / Q000378:metabolism; D002688:Chitinases / Q000378:metabolism*; D048271:Chitosan; D006868:Hydrolysis; D013294:Lactococcus lactis / Q000201:enzymology; D025282:Mycelium / Q000737:chemistry*; D009844:Oligosaccharides; D011994:Recombinant Proteins / Q000378:metabolism*; D014866:Waste Products
chemical_list: D009844:Oligosaccharides; D011994:Recombinant Proteins; D014866:Waste Products; C493484:oligochitosan; D002686:Chitin; D048271:Chitosan; D002688:Chitinases
keywords: Chitin; Chitinase; Hydrolysis; N,N′-diacetylchitobiose; Waste mycelium