A comparative study of the enzymatic hydrolysis of batch organosolv-pretreated birch and spruce biomass

Abstract

A shift towards a sustainable and green society is vital to reduce the negative effects of climate change associated with increased CO2 emissions. Lignocellulosic biomass is both renewable and abundant, but is recalcitrant to deconstruction. Among the methods of pretreatment available, organosolv (OS) delignifies cellulose efficiently, significantly improving its digestibility by enzymes. We have assessed the hydrolysability of the cellulose-rich solid fractions from OS-pretreated spruce and birch at 2% w/v loading (dry matter). Almost complete saccharification of birch was possible with 80 mg enzyme preparation/gsolids (12 FPU/gsolids), while the saccharification yield for spruce was only 70%, even when applying 60 FPU/gsolids. As the cellulose content is enriched by OS, the yield of glucose was higher than in their steam-exploded counterparts. The hydrolysate was a transparent liquid due to the absence of phenolics and was also free from inhibitors. OS pretreatment holds potential for use in a large-scale, closed-loop biorefinery producing fuels from the cellulose fraction and platform chemicals from the hemicellulose and lignin fractions respectively.Electronic supplementary materialThe online version of this article (10.1186/s13568-018-0643-y) contains supplementary material, which is available to authorized users.

Effect of lignin fractions isolated from different biomass sources on cellulose oxidation by fungal lytic polysaccharide monooxygenases

“…In the absence of acid, spruce was treated with 52% v/v ethanol and birch with 60% ethanol and pretreatment took place at 200 °C for 30 min [ 34 ]. Steam explosion pretreatment was performed for 5 min, at 225 °C with H 2 SO 4 0.5% w/w biomass for spruce and at 200 °C with H 2 SO 4 0.14% w/w biomass for birch [ 35 ]. The cellulose, hemicellulose and lignin content of each material are listed in Table 1 .…”

Tailoring Celluclast® Cocktail’s Performance towards the Production of Prebiotic Cello-Oligosaccharides from Waste Forest Biomass

“…Consequently, the response of the different materials to the pretreatment method that is being used is also distinctive. It has been reported that after the organosolv pretreatment of both birch and spruce biomass the lignin removal is more significant for birch than for spruce and therefore, the enzymatic digestibility showed higher improvement in the case of birch than in the case of spruce [33,34], as it can also be observed by the composition of the OS pretreated substrates that were used for this study.…”

Oligosaccharides production by enzymatic hydrolysis of banana pseudostem pulp

“…In this case, the reaction was evaluated until 48 h. Due to the very low enzyme dosage, the hydrolysis rate was lower, and the maximum TY achieved was below that the one obtained with 10 FPU/g DB (49% in contrast with 61%); however, if the analysis is made per unit of enzyme used, we obtained 49% against 6.1% when using 1 or 10 FPU, respectively. Also, OS selectivity decreases slowly in comparison to enzyme hydrolysis with 10 FPU/g DB, reaching 0.5 at 48 h. The differences between TY are not as big as the ones obtained by other authors when increasing the enzyme dosage, for example, [31] tripled the saccharification yield when doubling the enzyme dosage (3 FPU/g) working with pre-treated birch. This very low dosage of ).…”