Synergy between cellulases and pectinases in the hydrolysis of hemp
- a College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
- b Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
Abstract
The impact of pectinases in the hydrolysis of fresh, steam-exploded and ensiled hemp was investigated and the synergy between cellulases, pectinases and xylanase in the hydrolysis was evaluated. About half; 59.3% and 46.1% of pectin in the steam-exploded and ensiled hemp, respectively, could be removed by a low dosage of pectinases used. Pectinases were more efficient than xylanase in the hydrolysis of fresh and ensiled hemp whereas xylanase showed higher hydrolytic efficiency than the pectinase preparation used in the hydrolysis of steam-exploded hemp. Clear synergistic action between cellulases and xylanase could be observed in the hydrolysis of steam-exploded hemp. Supplementation of pectinase resulted in clear synergism with cellulases in the hydrolysis of all hemp substrates. Highest hydrolysis yield of steam-exploded hemp was obtained in the hydrolysis with cellulases and xylanase. In the hydrolysis of ensiled hemp, the synergistic action between cellulases and pectinases was more obvious for efficient hydrolysis.
Highlights
Abbreviations
- βG, glucosidase;
- CBH, cellobiohydrolases;
- CEL, cellulase;
- DM, dry matter;
- EG, endoglucanase;
- HPAEC-PAD, high-performance anion exchange chromatography coupled with pulsed amperometric detection;
- PEC, pectinase;
- SE hemp, steam-exploded hemp;
- XYL, xylanase
Keywords
- Hemp;
- Cellulases;
- Pectinase;
- Synergy;
- Enzymatic hydrolysis
Figures and tables from this article:
- Fig. 1. Hydrolysis of fresh, steam-exploded (SE) and ensiled hemp (20 g/l) by varying the ratio of xylanase and pectinases, with a total amount of 2 mg protein per gram DM for 48 h at pH 5.0 and 50 °C.
- Fig. 2. Reducing sugars (A) and galacturonic acid (B) released from fresh, steam-exploded (SE) and ensiled hemp (20 g/l) by pectinases (PEC) alone (1 mg/g DM), xylanase (XYL) alone (0.2, 1.0 and 5 mg/g DM) and the combination of PEC (1 mg/g DM) and XYL (0.2, 1.0 and 5 mg/g DM). Hydrolysis for 48 h at pH 5.0 and 50 °C. Error bars represent the standard errors.
- Fig. 3. Hydrolysis of fresh, SE and ensiled hemp (20 g/l) after 48 h hydrolysis by CEL alone (EGII 2 mg, CBHI 8 mg and βG 1 mg/g DM of substrate), CEL with PEC (1 mg/g DM), CEL with XYL (1 mg/g DM), or CEL with both PEC and XYL at pH 5.0 and 50 °C. Error bars represent the standard errors.
- Fig. 4. Hydrolysis of SE (filled symbols) and ensiled hemp (closed symbols) (20 g/l) after 48 h hydrolysis by CEL (EGII 2 mg, CBHI 8 mg and βG 1 mg/g DM of substrate) with accessory enzymes at pH 5.0 and 50 °C. PEC (circles) and XYL (squares) were dosage at 0, 0.2, 1, 2.5, and 5 mg/g DM, respectively. Error bars represent the standard errors.
- Table 1. Chemical composition (% of dry matter) of the hemp substrates (Pakarinen et al., 2012).
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- Table 2. Monosaccharides (g/l) and reducing sugars (g/l) released from fresh, SE and ensiled hemp (20 g/l) by pectinase (1, 5 or 20 mg protein per gram DM)¸ hydrolysis 48 h at pH 5.0 and 50 °C.
- The errors were calculated as the standard errors of the means.bdl: Below detection limit.
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- Table 3. Hydrolysis of fresh, SE and ensiled hemp (20 g/l) by various enzyme dosages (mg/g of DM) after 48 h by CEL alone (11 mg), CEL (11 mg) and PEC (1 mg), CEL (11 mg) and XYL (1 mg), CEL (11 mg), XYL (1 mg) and PEC (1 mg), at pH 5.0 and 50 °C.
- The errors were calculated as the standard errors of the means.bdl: Below detection limit.
- View Within Article
- Table 4. Synergy factor for formation of glucose by CEL with different accessory enzyme preparations: PEC (1 mg/g DM); XYL (1 mg/g DM); PEC and XYL (each 1 mg/g DM) in the hydrolysis of fresh, SE and ensiled hemp after 48 h hydrolysis at pH 5.0 and 50 °C.
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Copyright © 2012 Elsevier Ltd. All rights reserved.
