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Improving the tailorability of hydrochar synthesis is an effective way to enhance its performance and utilization efficiency. In this study, the growth rate, morphology, and molecular structure of hydrochar were controlled by regulating the pH and temperature of the hydrothermal carbonization process. Growth process analysis indicates that hydrochar has three growth periods: induction, rapid, and stable growth periods. It is mainly controlled by 5-hydroxymethylfurfural (HMF), which is formed by converting glucose and its transformation products. The regulation of acid can significantly shorten the induction period of hydrochar, even under low-temperature conditions (<180℃), and increase the growth rate of hydrochar. However, the degree of hydrochar adhesion varies: the lower the temperature, the greater the degree of its adhesion. Molecular structural analysis demonstrates that hydrochar mainly consists of furan structural domains and aromatic clusters, and its surface is rich in oxygen-containing functional groups. The degree at which hydrochar was aromatized was improved by increasing the reaction temperature (160-220℃); whereas the regulation of acid reduced it and increased the content of oxygen-containing functional groups on the hydrochar surface. Based on these results, it is proposed that hydrochar formation has five stages and three growth periods with or without acid regulation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Ethnopharmacological Relevance: Senkyunolide H (SNH) is a bioactive phthalide isolated from Ligusticum chuanxiong Hort rhizome and was reported to have multiple pharmacological effects., Aim of the Study: The study was performed to verify the potency of SNH protecting PC12 cells from oxygen glucose deprivation/reperfusion (OGD/R)-induced injury and to elucidate the underlying mechanisms., Materials and Methods: OGD/R model was established in PC12 cells and the cell viability was measured by MTT assay. The cell morphology was observed using scanning electron microscope (SEM). The potential targets of SNH and related targets of OGD/R were screened, and a merged protein-protein interaction (PPI) network of SNH and OGD/R was constructed based on the network pharmacology analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) database was used for pathway analysis. Intracellular cAMP level and the protein expression levels were measured to elucidate the underlying mechanisms., Results: SNH pretreatment protected PC12 cells against OGD/R-induced cell death. SNH also significantly protected the cell protrusion. A merged PPI network was constructed and the shared candidate targets significantly enriched in cAMP signaling pathway. The level of intracellular cAMP and the protein level of p-CREB, p-AKT, p-PDK1 and PKA protein were up-regulated after the treatment of SNH compared with OGD/R modeling., Conclusions: The present study indicated that SNH protected PC12 cells from OGD/R-induced injury via cAMP-PI3K/AKT signaling pathway., (Copyright © 2021 Elsevier B.V. All rights reserved.)

A pretreatment method combining ball-milling, ultrasound, and hydrothermal treatment was developed to produce xylooligosaccharides (XOS) and glucose with a high yield from corn stover. Under optimal conditions, the yield of XOS reached 80.40%, and the functional XOS (X2-X4) took up to 26.97%. Small amount of inhibitors were formed during the hydrothermal process. Enzymatic hydrolysis of the hydrothermally pretreated residue gave 92.60% yield of glucose, leaving lignin as the final residue which accounted for 66.82% of native lignin. The correlations between the yield of glucose and the physio-chemical properties of corn stover, such as crystalline index, particle size, and the removal of xylan, were established to understand the recalcitrance removal during the pretreatment process. Results demonstrate that this combined pretreatment method is a green and effective process to selectively separate the hemicellulose fractions and improve both production of XOS and glucose yield., (Copyright © 2021. Published by Elsevier Ltd.)

A challenge of today's industry is to transform low-value side products into more value-added materials. The acid-catalyzed conversion of hemi(cellulose) to platform chemicals in green chemical/fuel production and biorefinery yields large formation of insoluble byproduct called humin. Herein, humin obtained from dehydration of glucose was transformed into a novel class of effective carbonaceous solid acid catalyst for the first time via low-temperature pyrolysis followed by sulfonation. A range of preparation conditions were investigated, and the structure-function relationships of the resulting catalysts were also discussed based on the analysis of structure and composition. Comparing with the glucose-derived carbon catalyst, the humin-derived catalyst has substantially larger surface area and higher SO 3 H density, which enable it to display higher catalytic activity and efficiency not only in esterification of levulinic acid and n-butanol (yield = 95.0%, 373 K), but also in hydroxyalkylation/alkylation of 2-methylfuran and furfural (yield = 64.2%, 323 K). Additionally, the catalyst could be repeatedly employed for at least four cycles without obvious deactivation, exhibiting good reusability. This work provides a green method to convert humin byproduct into economic and eco-friendly solid acid catalyst and may contribute to a holistic approach for biomass utilization., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Glucose phosphorylation by glucokinase exhibits a sigmoidal dependency on substrate concentration regardless of its simple structure. Dimorph mechanism suggested the existence of two enzymatic states with different catalytic properties, which has been shown to be plausible by structural analysis. However, the dimorph mechanism gives rise to a complicated or non-explicit non-closed mathematical form. It is neither feasible to apply the dimorph mechanism in effector characterizations. To improve the area of glucokinase study with stronger theoretical support and less complication in computation, we proposed the investigation of the enzyme from a pseudo-dimeric angle. The proposed mechanism started from the idealization of two monomeric glucokinase as a dimeric complex, which significantly simplified the glucose phosphorylation kinetics, while the differences in enzyme reconfiguration caused by variable substrates and effectors have been successfully characterized. The study presented a simpler and more reliable way in studying the properties of glucokinase and its effectors, providing guidelines of effector developments for hyperglycemia and hypoglycemia treatment.

Curcuminoids (cus) have attracted increasing attention because of the antioxidant, anticancer, and antitumor activities while their production is limited because of its main source, turmeric plant, demonstrates extensive seasonal variation. In this study, we constructed Escherichia coli co-culture system for the rapid production of curcuminoids from glucose. Firstly, the overexpression of curcuminoid synthase and four different strategies related to increasing the intracellular malonyl-CoA pool were conducted in engineered E. coli. We found that bisdemethoxycurcumin (BDMC) is the main product and that high level of malonyl-CoA pool is essential for BDMC production. We also obtained the maximum titer (13.8 mg L -1 ) of BDMC within 4 h by fast preparation directly from p-coumaric acid. Secondly, we developed a process for BDMC synthesis from glucose using a co-culture system where an E. coli strain is used to produce p-coumaric acid from glucose and another E. coli strain converted p-coumaric acid into the final product. Compared to the mono-culture system, the co-culture is more potent and resulted in 6.28 mg L -1 of BDMC from glucose within 22 h of fermentation in a 3-L bioreactor. This is the first time a co-culture method is employed for the production of curcuminoids from glucose in a lab scale bioreactor. This system provides a new method transforming inexpensive substrate into value-added products., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

To enhance the cellulose digestibility of energy grass hybrid Pennisetum (P. americanum×P. purpureum, HP) with low energy-consumption and high efficiency, a novel combinatorial pretreatment of oxygen-aqueous alkaline ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([Emim]Ac) media (OEA) was developed in this work. The combinatorial pretreatment was performed under the relatively low temperature (120°C), short retention time (30min), and 12bar oxygen pressure. The combinatorial pretreatment of OEA was demonstrated effectively for pretreatment of hybrid Pennisetum, which evidenced by the removal of lignin, degradation of carbohydrate, and porosity property of the regenerated biomass. Subsequently, a higher glucose recovery (96.9%) at a low enzyme loading (20FPU/g substrate) was obtained by the OEA pretreatment, and it was 9.1 times as much as the untreated samples. Overall, the novel OEA combinatorial pretreatment has the advantages of low thermal energy input and enzyme usage, and short retention time., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

This work investigates an automated technique for rapid detecting the glucose content in glucose injection by reaction headspace gas chromatography (HS-GC). This method is based on the oxidation reaction of glucose in glucose injection with potassium dichromate. The carbon dioxide (CO 2 ) formed from the oxidation reaction can be quantitatively detected by GC. The results show that the relative standard deviation (RSD) of the present method was within 2.91%, and the measured glucose contents in glucose injection closely match those quantified by the reference method (relative differences <6.45%). The new HS-GC technique is rapid, practical and can be used to the batch detection of the glucose content in glucose injection related applications., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Co-production of glucose, furfural and other green materials based on a lignocellulosic biorefinery is a promising way to realize the commercial application of corncob residues. An effective process was developed for glucose production using low temperature bisulfite pretreatment and high-solids enzymatic hydrolysis. Corncob residues from furfural production (FRs) were pretreated with 0.1g NaHSO 3 /g dry substrate at 100°C for 3h. Lignin was sulfonated and sulfonic groups were produced during pretreatment, which resulted in decreasing the zeta potential of the samples. Compared with raw material, bisulfite pretreatment of FRs increased the glucose yield from 18.6 to 99.45% after 72h hydrolysis at a solids loading of 12.5%. The hydrolysis residues showed a relatively high thermal stability and concentrated high derivatives. Direct pretreatment followed by enzymatic hydrolysis is an environmentally-friendly and economically-feasible method for the production of glucose and high-purity lignin, which could be further converted into high-value products., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The principal goal of this work was to reuse the carbohydrates and recycle sulfuric acid in the waste liquid of acid hydrolysis nanocrystalline cellulose (NCC). Therefore, in this work, the optimizations of further hydrolysis of waste liquid of acid hydrolysis NCC and catalytic conversion of L4 to 5-hydroxymethylfurfural (5-HMF) were studied. Sulfuric acid was separated by spiral wound diffusion dialysis (SWDD). The results revealed that cellulose can be hydrolyze to glucose absolutely under the condition of temperature 35 °C, 3 h, and sulfuric acid's concentration 62 wt%. And 78.3% sulfuric acid was recovered by SWDD. The yield of 5-HMF was highest in aqueous solution under the optimal condition was as follows, temperature 160 °C, 3 h, and sulfuric acid's concentration 12 wt%. Then the effect of biphasic solvent systems catalytic conversion and inorganic salt as additives were still examined. The results showed that both of them contributed to prepare 5-HMF. The yield and selectivity of 5-HMF was up to 21.0% and 31.4%, respectively., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This study reports four schemes to pretreat wet furfural residues (FRs) with sodium bisulfite for production of fermentable sugar. The results showed that non-detoxified FRs (pH 2-3) had great potential to lower the cost of bioconversion. The optimal process was that unwashed FRs were first pretreated with bisulfite, and the whole slurry was then directly used for enzymatic hydrolysis. A maximum glucose yield of 99.4% was achieved from substrates pretreated with 0.1 g NaHSO3/g dry substrate (DS), at a relatively low temperature of 100 °C for 3 h. Compared with raw material, enzymatic hydrolysis at a high-solid of 16.5% (w/w) specifically showed more excellent performance with bisulfite treated FRs. Direct bisulfite pretreatment improved the accessibility of substrates and the total glucose recovery. Lignosulfonate in the non-detoxified slurry decreased the non-productive adsorption of cellulase on the substrate, thus improving enzymatic hydrolysis., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Integrating polypyrrole-cellulose nanocrystal-based composites with glucose oxidase (GOx) as a new sensing regime was investigated. Polypyrrole-cellulose nanocrystal (PPy-CNC)-based composite as a novel immobilization membrane with unique physicochemical properties was found to enhance biosensor performance. Field emission scanning electron microscopy (FESEM) images showed that fibers were nanosized and porous, which is appropriate for accommodating enzymes and increasing electron transfer kinetics. The voltammetric results showed that the native structure and biocatalytic activity of GOx immobilized on the PPy-CNC nanocomposite remained and exhibited a high sensitivity (ca. 0.73 μA·mM(-1)), with a high dynamic response ranging from 1.0 to 20 mM glucose. The modified glucose biosensor exhibits a limit of detection (LOD) of (50 ± 10) µM and also excludes interfering species, such as ascorbic acid, uric acid, and cholesterol, which makes this sensor suitable for glucose determination in real samples. This sensor displays an acceptable reproducibility and stability over time. The current response was maintained over 95% of the initial value after 17 days, and the current difference measurement obtained using different electrodes provided a relative standard deviation (RSD) of 4.47%.

Hydrothermal conversion (HTC) is an important thermochemical process to upgrade low-cost biomass into valuable chemicals or fuels. As compared with non-catalytic HTC, catalytic HTC shows high energy efficiency on biomass upgradation. In this work, the catalytic performances of various transition metal sulfates (Mn(2+), Fe(2+), Fe(3+), Co(2+), Ni(2+), Cu(2+), and Zn(2+)) in the HTCs of xylose, glucose, and cellulose under different conditions were explored. Among these catalysts, Zn(2+) and Ni(2+) showed obvious effects on the conversions of xylose, glucose, and cellulose into lactic acid, while Cu(2+) and Fe(3+), which could significantly accelerate the hydrolysis of cellulose into glucose at 200°C, displayed high efficiency on converting glucose and cellulose into levulinic acid and formic acid at high temperature. Additionally, significant positive correlative relationships among xylose, glucose, and cellulose degradations were observed. This study is helpful for screening appropriate catalysts for biomass upgradation through catalytic HTC of monosaccharide., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

In this work, the effects of carbon sources and culture media on the production and structural properties of bacterial cellulose (BC) have been studied. BC nanofibers were synthesized using Gluconacetobacter xylinus strain PTCC 1734. Media used were Hestrin-Schramm (H), Yamanaka (Y), and Zhou (Z). Five different carbon sources, namely date syrup, glucose, mannitol, sucrose, and food-grade sucrose were used in these media. All the produced BC pellicles were characterized in terms of dry weight production, biomass yield, thermal stability, crystallinity and morphology by thermogravimetric analysis (TGA), x-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM). The obtained results showed that mannitol lead to the highest yield, followed by sucrose. The highest production efficiency of mannitol might be due to the nitrogen source, which plays an important role. The maximum improvement on the thermal stability of the composites was achieved when mannitol was used in H medium. In addition, the crystallinity was higher in BC formed in H medium compared to other media. FE-SEM micrographs illustrated that the BC pellicles, synthesized in the culture media H and Z, were stable, unlike those in medium Y that were unstable. The micrographs of BC produced in media containing mannitol and sucrose provided evidence of the strong interfacial adhesion between the BC fibers without noticeable aggregates., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Three different pre-extraction methods (i.e., acetic acid, sulfuric acid and sodium hydroxide) were used for the pretreatment followed by chemi-thermomechanical treatments and then enzymatic hydrolysis of wheat straw to produce fermentable sugars. The performance of enzymatic hydrolysis by the synergistic effect of pre-extractions and chemi-thermomechanical treatments was remarkable. Results showed that the pre-extraction combining with the chemi-thermomechanical treatments shorten the enzymatic hydrolysis time and improved the glucose yield at the same enzyme loadings. The chemical components, swelling ability, and crystallinity, as well as the surface morphology of the substrates were changed obviously. All of these changes can affect the accessibility of enzymes to cellulose in the substrates to a certain extent., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Cellulosic sludge from paper mills making bleached products can be enzymatically converted to glucose. A kinetic model that accounts for product inhibition was used to estimate the cost:benefits of the process. In the proposed scheme, the sludge is enzymatically hydrolyzed in a sequence of CSTRs, the ash separated, and the product glucose concentrated through reverse osmosis. The water recovered is mostly recycled. By far, the most important economic variable is the value of the glucose. However, even if the glucose is assumed to be of no value the avoided cost of sludge disposal approximately offsets the process costs. The approach should generate significant revenue if the glucose is valued at market.

Combination of liquid hot water pretreatment (LHWP) and wet disk milling (WDM) was investigated in this study to enhance the sugar recovery yield both in prehydrolyzate and enzymatic hydrolyzate. The results show that WDM with LHWP at 180 °C for 20 min produced maximum xylose and glucose yields of 91.62% and 88.12%, respectively, which are higher than that of dilute acid pretreatment or individual LHWP. Corresponding concentration of fermentation inhibitors such as acetic acid, HMF, and furfural in the prehydrolyzate are about 0.98, 0.07 and 0.78 g/L, respectively, which indicated that the detoxification may be not required in the next fermentation step. The acid-insoluble lignin recovery in the insoluble solid resulting from enzymatic hydrolysis, was 25.67/100g raw material, representing 90.7% of acid-insoluble lignin in the eucalyptus biomass. It can be concluded that liquid hot water pretreatment combined with wet disk milling can be successfully applied to eucalyptus., (Copyright © 2012. Published by Elsevier Ltd.)

The structure-function relationships of plant oligomeric globulins are still not fully recognized. The present work investigated the influence of glycation with glucose (at 1:50 and 1:100 protein/sugar molar ratios; incubation periods of 2.5, 5.0, and 10.0 h) on the physicochemical and conformational properties of kidney bean vicilin (phaseolin), with the aim of understanding the structure-function relationships of legume vicilins. Protein solubility (PS), surface charge (isoelectric point) and hydrophobicity (H0), and secondary, tertiary, and/or quaternary conformations, as well as the emulsifying activities (emulsifying activity and emulsion stability indices, EAI and ESI) were evaluated. The 2.5 h incubation period of glycation led to least PS and highest H0, and after that, the PS and H0, on the contrary, gradually changed with increasing incubation period. The glycation increased the α-helix content and highly ordered secondary structures (α-helix+β-strand), as evidenced by far-UV circular dichroism (CD) spectroscopy. Combined analyses of differential scanning calorimetry, intrinsic emission fluorescence, and near-UV CD spectroscopy indicated that phaseolin underwent a tertiary conformation unfolding and subsequent rearrangement process (to form a new tertiary conformation), whereas the quaternary conformational flexibility progressively increased upon increasing degree of glycation. The conformation rearrangement was more distinct at the 1:100 molar ratio than at the 1:50 counterpart. The glycation at 5.0 and 10.0 h periods considerably increased the EAI, but only at the 1:50 molar ratio was the ESI progressively increased with the incubation period. These results confirmed that besides surface properties (e.g., PS and H0), the flexibility in tertiary and/or quaternary conformations played a major role in the emulsifying properties of glycated vicilins. The findings would have important implications for understanding the structure-function relationships of legume oligomeric globulins, thus providing a direction to further improve the surface-related functional properties of these proteins.

Ru/MCM-41 catalyst prepared by an impregnation-formaldehyde reduction method showed higher catalytic activity and sorbitol selectivity than other catalysts in the hydrogenation of glucose. SEM and XRD indicated the partial surface properties of Ru/MCM-41. Moreover, Ru dispersion and Ru surface area of Ru/MCM-41 were determined by pulse chemisorption, and the result further proved that Ru/MCM-41 had higher catalytic activity. A catalyst recycling experiment demonstrated that Ru/MCM-41 was a better catalyst and it could be reused three or four times. A speculated mechanism was proposed to illustrate the detailed process of d-glucose hydrogenation to produce sorbitol., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Buddleja davidii is a unique biomass that has many attractive agroenergy features, especially its wide range of growth habitat. The anatomical characteristics of B. davidii were investigated before and after ethanol organosolv pretreatment (one of the leading pretreatment technologies) in order to further understand the alterations that occur to the cellular structure of the biomass which can then be correlated with its enzymatic digestibility. Results showed that the ethanol organosolv pretreatment of B. davidii selectively removes lignin from the middle lamella (ML), which does not significantly disrupt the crystalline structure of cellulose. The removal of ML lignin is a major factor in enhancing enzymatic cellulose-to-glucose hydrolysis. The pretreatment also causes cell deformation, resulting in cracks and breaks in the cell wall. These observations, together with characterization analysis of the cell wall polymer material, lend support to the hypothesis that the physical distribution of lignin in the biomass matrix is an important structural feature affecting biomass enzymatic digestibility., (© 2010 Wiley Periodicals, Inc.)

Three different pretreatment methods for switchgrass were studied. Aqueous sodium hydroxide (0.5-10% w/v, 90 degrees C, 1h), dilute H(2)SO(4) (0.5-6.0% v/v, 121 degrees C, 1h) and hot water (100 degrees C, 1h) were employed in this study to determine how each method affected the digestibility of switchgrass during enzymatic hydrolysis. Switchgrass pre-treated with 0.5% w/v sodium hydroxide generally produced glucose in higher concentrations than sulfuric acid and hot water pre-treated samples. SEM studies on the pre-treated samples revealed a great deal of pore formation in the NaOH pre-treated samples and little or no physical changes on the acid and hot water pre-treated samples. Lignin analysis carried out on the pre-treated samples showed a considerable decrease in lignin content in the NaOH pre-treated samples and only a slight decrease in lignin content for the other pretreatment methods studied., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

We studied the process of conversion of microcrystalline-cellulose into fermentable glucose in the formic acid reaction system using cross polarization/magic angle spinning (13)C-nuclear magnetic resonance, X-ray diffraction and Fourier transform infrared spectroscopy. The results indicated that formic acid as an active agent was able to effectively penetrate into the interior space of the cellulose molecules, thus collapsing the rigid crystalline structure and allowing hydrolysis to occur easily in the amorphous zone as well as in the crystalline zone. The microcrystalline-cellulose was hydrolyzed using formic acid and 4% hydrochloric acid under mild conditions. The effects of hydrochloric acid concentration, the ratio of solid to liquid, temperature (55-75 degrees C) and retention time (0-9 h), and the concentration of glucose were analyzed. The hydrolysis velocities of microcrystalline-cellulose were 6.14 x 10(-3) h(-1) at 55 degrees C, 2.94 x 10(-2) h(-1) at 65 degrees C, and 6.84x10(-2) h(-1) at 75 degrees C. The degradation velocities of glucose were 0.01 h(-1) at 55 degrees C, 0.14 h(-1) at 65 degrees C, 0.34 h(-1) at 75 degrees C. The activation energy of microcrystalline-cellulose hydrolysis was 105.61 kJ/mol, and the activation energy of glucose degradation was 131.37 kJ/mol.

This work introduces, for the first time worldwide, the means to preserve and protect the natural nanoporous structure of the never-dried plant cell wall, against the irreversible collapse, which occurs due to drying. Simultaneously, these means, used for the above-mentioned aim, provide a gateway to novel nanocomposite materials, which retain the super reactive and super absorbent properties of the never-dried biological cellulose fibers. The present work showed, for the first time worldwide, that glucose can be vaccinated into the cell wall micropores or nanostructure of the never-dried biological cellulose fibers, by simple new techniques, to create a reactive novel nanocomposite material possessing surprising super absorbent properties. Inoculation of the never dried biological cellulose fibers, with glucose, prevented the collapse of the cell wall nanostructure, which normally occurs due to drying. The nanocomposite, produced after drying of the glucose inoculated biological cellulose, retained the super absorbent properties of the never dried biological cellulose fibers. It was found that glucose under certain circumstances grafts to the never dried biological cellulose fibers to form a novel natural nanocomposite material. About 3-8% (w/w) glucose remained grafted in the novel nanocomposite.