cellulase and sodium-carbonate

Mesona chinensis has been used as a Chinese folk medicine and main ingredient used to make "black bean jelly" in Asia for hundreds of years. In this study, two polysaccharides (MCP-C and MCP-S) from Mesona chinensis were extracted by using cellulase assisted extraction (CAE) and sodium carbonate assisted extraction (SAE), separately. Then the different physicochemical characteristics, rheological and thermal properties of two polysaccharides were analyzed by ion chromatography, high-performance gel permeation chromatography (HPGPC), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), rheological and thermogravimetric analysis. Results indicated that the contents of total sugar and uronic acid of MCP-C were higher than MCP-S, while the protein content and molecular weight was lower than that of MCP-S. MCP-S and MCP-C had differences in the surface morphology by SEM, while they all had the typical IR spectra characteristic and amorphous morphology of polysaccharides. The rheological experiments showed that MCP-C and MCP-S exhibited typical pseudoplasticity fluids behavior. The apparent viscosity (η), storage modulus (G') and complex viscosity (η*) of MCP-S were higher than MCP-C. The three-stage decomposition patterns were observed in MCP-C and MCP-S. MCP-S was more stable and had higher initial decomposition temperature (Ti) than MCP-C.

Topics: Carbonates; Cellulase; Lamiaceae; Molecular Weight; Monosaccharides; Polysaccharides; Rheology; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared; Temperature; X-Ray Diffraction

Mechanical refining has been shown to improve biomass enzymatic digestibility. In this study industrial high-yield sodium carbonate hardwood pulp was subjected to lab, pilot and industrial refining to determine if the mechanical refining improves the enzymatic hydrolysis sugar conversion efficiency differently at different refining scales. Lab, pilot and industrial refining increased the biomass digestibility for lignocellulosic biomass relative to the unrefined material. The sugar conversion was increased from 36% to 65% at 5 FPU/g of biomass with industrial refining at 67.0 kWh/t, which was more energy efficient than lab and pilot scale refining. There is a maximum in the sugar conversion with respect to the amount of refining energy. Water retention value is a good predictor of improvements in sugar conversion for a given fiber source and composition. Improvements in biomass digestibility with refining due to lab, pilot plant and industrial refining were similar with respect to water retention value.

Topics: Biotechnology; Carbohydrates; Carbonates; Cellulase; Hydrolysis; Industry; Paper; Pilot Projects; Thermodynamics; Wood

Process simulation and lab trials were carried out to demonstrate and confirm the efficiency of the concept that recycling hydrolysate at low total solid enzymatic hydrolysis is one of the options to increase the sugar concentration without mixing problems. Higher sugar concentration can reduce the capital cost for fermentation and distillation because of smaller retention volume. Meanwhile, operation cost will also decrease for less operating volume and less energy required for distillation. With the computer simulation, time and efforts can be saved to achieve the steady state of recycling process, which is the scenario for industrial production. This paper, to the best of our knowledge, is the first paper discussing steady-state saccharification with recycling of the filtrate form enzymatic hydrolysis to increase sugar concentration. Recycled enzymes in the filtrate (15-30% of the original enzyme loading) resulted in 5-10% higher carbohydrate conversion compared to the case in which recycled enzymes were denatured. The recycled hydrolysate yielded 10% higher carbohydrate conversion compared to pure sugar simulated hydrolysate at the same enzyme loading, which indicated hydrolysis by-products could boost enzymatic hydrolysis. The high sugar concentration (pure sugar simulated) showed inhibition effect, since about 15% decrease in carbohydrate conversion was observed compared with the case with no sugar added. The overall effect of hydrolysate recycling at WinGEMS simulated steady-state conditions with 5% total solids was increasing the sugar concentration from 35 to 141 g/l, while the carbohydrate conversion was 2% higher for recycling at steady state (87%) compared with no recycling strategy (85%). Ten percent and 15% total solid processes were also evaluated in this study.

Topics: Biomass; Carbohydrates; Carbonates; Cellulase; Cellulose; Chromatography, High Pressure Liquid; Computer Simulation; Endo-1,4-beta Xylanases; Ethanol; Fermentation; Hydrolysis; Lignin; Recycling; Sulfides; Sulfuric Acids; Wood; Xylans

In this study, a strategy to reduce enzyme dosage is evaluated by applying two post-treatments, oxygen delignification and mechanical refining. The sugar conversion for GL12 substrates was increased from 51.5% to 77.9% with post-treatments at the enzyme dosage of 10 FPU. When the amount of enzyme was reduced to 5 FPU with post-treatments, the conversion of 71.8% was obtained, which was significant higher than the conversion without any post-treatment using 10 FPU (51.5%). This clearly demonstrates the benefit of post-treatments that allows more than 50% of enzyme reduction at the same level of enzymatic conversion. Enzyme-accessible surface area and pore volume were evaluated by Simons' staining and DSC thermoporometry methods, and strong correlations were found with the sugar conversion.

Topics: beta-Glucosidase; Biofuels; Biomass; Bioreactors; Carbonates; Cellulase; Endo-1,4-beta Xylanases; Ethanol; Fermentation; Hydrolysis; Industrial Microbiology; Lignin; Monosaccharides; Oxygen; Porosity; Sulfides; Temperature; Wood