Process Evaluation of Enzymatic Hydrolysis with Filtrate Recycle for the Production of High Concentration Sugars

Abstract Background Hydrogen peroxide–acetic acid (HPAA) is widely used in pretreatment of lignocellulose because it has a good capability in selective delignification. However, high concentration (more than 60%) of HPAA increases the cost of pretreatment and the risk of explosion. In this work, alkaline post-incubation was employed to decrease the HPAA loading and improve the saccharification of poplar. Results Pretreatment with 100% HPAA removed 91.0% lignin and retained 89.9% glucan in poplar. After poplar was pretreated by 100% HPAA at 60 °C for 2 h, the glucan conversion in enzymatic hydrolysis by cellulase increased to 90.1%. Alkaline incubation reduced the total lignin, surface lignin, and acetyl group of HPAA-pretreated poplar. More than 92% acetyl groups of HPAA-pretreated poplar were removed by alkaline incubation with 1.0% NaOH at 50 °C for 1 h. After incubation of 60% HPAA-pretreated poplar with 1.0% NaOH, the glucan conversion enhanced to 95.0%. About 40% HPAA loading in pretreatment was reduced by alkaline incubation without the decrease of glucose yield. Conclusions Alkaline post-incubation had strong ability on the deacetylation and delignification of HPAA-pretreated poplar, exhibiting a strong promotion on the enzymatic hydrolysis yield. This report represented alkaline incubation reduced the HPAA loading, improved pretreatment safety, exhibiting excellent potential application in saccharification of poplar.

Download Full-text

High yield and high concentration glucose production from corncob residues after tetrahydrofuran + H2O co-solvent pretreatment and followed by enzymatic hydrolysis

Renewable and Sustainable Energy Reviews ◽

10.1016/j.rser.2020.110107 ◽

2020 ◽

Vol 132 ◽

pp. 110107

Author(s):

Fengpei Yao ◽

Fei Shen ◽

Xue Wan ◽

Changwei Hu

Keyword(s):

Enzymatic Hydrolysis ◽

Glucose Production ◽

High Yield ◽

High Concentration

Download Full-text

High concentration and yield production of mannose from açaí (Euterpe oleracea) seeds via diluted-acid and mannanase-catalyzed hydrolysis

10.1101/513168 ◽

2019 ◽

Author(s):

Alvaro Ferreira Monteiro ◽

Ingrid Santos Miguez ◽

João Pedro R. Barros Silva ◽

Ayla Santana Silva

Keyword(s):

Enzymatic Hydrolysis ◽

Dry Weight ◽

List Type ◽

Euterpe Oleracea ◽

High Concentration ◽

Limited Effect ◽

Yield Production ◽

Total Carbohydrates ◽

High Concentrations ◽

Mature Seeds

AbstractThe açaí berry’s seed corresponds to 85–95% of the fruit’s weight and represents ~1.1 million tons of residue yearly accumulated in the Amazon region. This study confirmed that mannan is the major component of mature seeds, corresponding to 80% of the seed’s total carbohydrates and about 50% of its dry weight. To convert this high mannan content into mannose, a sequential process of diluted acid and enzymatic hydrolysis was evaluated. Diluted-H2SO4 hydrolysis (3%-acid, 60-min, 121°C) resulted in a 30% mannan hydrolysis yield and 41.7 g/L of mannose. Because ~70% mannan remained in the seed, a mannanase-catalyzed hydrolysis was sequentially performed with 2–20% seed concentration, reaching 146.3 g/L of mannose and a 96.8% yield with 20% solids. As far as we know, this is the highest reported concentration of mannose produced from a residue. Thus, this work provides fundamental data for achieving high concentrations and yields of mannose from açaí seeds.HighlightsMannan was confirmed as the major component (~50%) of açaí seeds.Diluted-H2SO4 hydrolysis had a limited effect on mannan conversion into mannose.Enzymatic hydrolysis was sequentially performed with a high seed concentration.Mannan was efficiently hydrolyzed by mannanases, producing a 96.8% yield.Mannose production of 146.3 g/L was obtained with mannanase-catalyzed hydrolysis.Graphical abstract

Download Full-text