Biomass Carbohydrate Research Articles

Synthesis of Biobased Polyols from Soybean Meal for Application in Rigid Polyurethane Foams

Soybean meal or soymeal is an inexpensive protein–carbohydrate biomass and a coproduct of soybean processing. The composition of soymeal was determined before using it for the polyol synthesis. The...

The morphological and chemical properties of fine roots respond to nitrogen addition in a temperate Schrenk\u2019s spruce (Picea schrenkiana) forest

Fine roots (< 2 mm in diameter) play an important role in belowground ecosystem processes, and their physiological ecology is easily altered by nitrogen deposition. To better understand the response of physiological and ecological processes of fine roots to nitrogen deposition, a manipulation experiment was conducted to investigate the effects of exogenous nitrogen addition (control (0 kg ha−1 a−1), low (5 kg ha−1 a−1), moderate (10 kg ha−1 a−1), and high nitrogen (20 kg ha−1 a−1)) on the biomass, morphological characteristics, chemical elements and nonstructural carbohydrates of fine roots in a Picea schrenkiana forest. We found that most fine roots were located in the 0–20 cm of soil layer across all nitrogen treatment groups (42.81–52.09% of the total biomass). Compared with the control, the biomass, specific root length and specific root area of the fine roots increased in the medium nitrogen treatment, whereas the fine roots biomass was lower in the high nitrogen treatment than in the other treatments. In fine roots, nitrogen addition promotes the absorption of nitrogen and phosphorus and their stoichiometric ratio, while reducing the content of nonstructural carbohydrates. The content of nonstructural carbohydrates in the small-diameter roots (< 1 mm in diamter) in each nitrogen treatment group was lower than that in the large-diameter roots. Correlation analysis showed that soil carbon and nitrogen were positively correlated with fine root biomass and specific root length and negatively correlated with the nonstructural carbohydrates. Our findings demonstrate that medium nitrogen addition is conducive to the development of fine root morphology, while excessive nitrogen can suppress the growth of root systems.

Intensification of Biomass Thermal Deoxygenation via a Two-Stage Process

Thermal deoxygenation (TDO) is a promising reaction scheme for producing low oxygen bio-oil from biomass carbohydrate. The primary step in bio-oil production involves pyrolysis of alkaline earth metal-neutralized biomass hydrolysates at 723 K yielding bio-oil, chars, carbonates, and light gases. Reactor scaling from bench to floor-scale, however, reduced carbon yields from 80% to 48% of theoretical, respectively. This paper details a two-stage process to intensify the TDO process, improving carbon yields to 79% of theoretical. The scheme involves a 523 K thermal pretreatment (stage I) to yield a polysalt and transition of a melt-phase. The resulting solid polysalt is reduced to powder to improve material handling and reaction rates during decomposition at 723 K (stage II). Resulting bio-oil yield is shown to improve from 0.082 to 0.16 kg-oil/kg-feed. A two-step reaction model is developed detailing the reaction rates and regimes which can guide continuous process design efforts.

Sorption of Methylene Blue for Studying the Specific Surface Properties of Biomass Carbohydrates

The surface area is an important parameter in setting any biorefining technology. The aim of this study was to investigate the applicability of sorption of methylene blue to characterize the surface of the main biomass carbohydrates: α-cellulose, sigmacell cellulose, natural gum, β-glucan, and starch. The morphology of particles of the model objects was studied by scanning electron microscopy. Nitrogen adsorption isotherms demonstrate that the selected carbohydrates are macroporous adsorbents. The monolayer capacities, the energy constants of the Brunauer–Emmett–Teller (BET) equation, and specific surface areas were calculated using the BET theory, the comparative method proposed by Gregg and Sing, and the Harkins–Jura method. The method of methylene blue sorption onto biomass carbohydrates was adapted and mastered. It was demonstrated that sorption of methylene blue proceeds successfully in ethanol, thus facilitating surface characterization for carbohydrates that are either soluble in water or regain water. It was found that the methylene blue sorption values correlate with specific surface area determined by nitrogen adsorption/desorption and calculated from the granulometric data. As a result of electrostatic attraction, the presence of ion-exchanged groups on the analyte surface has a stronger effect on binding of methylene blue than the surface area does. Sorption of methylene blue can be used in addition to gas adsorption/desorption to assess the accessibility of carbohydrate surface for binding large molecules.

Collaborative Conversion of Biomass Carbohydrates into Valuable Chemicals: Catalytic Strategy and Mechanism Research.

Levulinate is one of the high added-value biomass-derived chemicals that is primarily produced from hexoses in cellulose and hemicellulose. Producing levulinate from pentoses in hemicellulose that is extensively distributed in biomass is still highly challenging. In this study, biomass materials and carbohydrates (including cellulose, xylan, glucose, fructose, and xylose) were collaboratively converted into levulinates efficiently over various zeolites with ethanol/dimethoxymethane as cosolvents. The key process for converting pentoses into levulinates is the synthesis of intermediates (furfural) into alkoxy methyl furfural via electrophilic substitution or their conversion into furfuryl alcohol via in situ hydrogenation. The substitution was achieved by the synergic effect between bifunctional catalysts and cosolvents, which promotes conversion of furfural into alkoxy methyl furfural via the electrophilic addition of alkoxy methyl radicals. Hydrogenation of furfural into furfuryl alcohol was impelled by the cooperative process between in situ generated H-donor from alcohol solvents and zeolite catalysts. Moreover, a favorable yield of 21.05 mol % of levulinates was achieved by simultaneous and collaborative conversion of cellulose and hemicellulose with the one-pot process using ethanol/dimethoxymethane as a cosolvent and the zeolite with B and L acid sites as a catalyst.

Deep Delignification of Woody Biomass by Repeated Mild Alkaline Treatments with Pressurized O2.

Delignification is essential in effective utilization of carbohydrates of lignocellulosic biomass. Characteristics of the delignification are important for the yield and property of the resulting carbohydrates. Oxidation with O2 of biomass in alkaline water can potentially produce high-purity cellulose at high yield. The present authors chose a Japanese cedar and investigated its oxidative delignification at 90 °C. The delignification selectivity was determined mainly by the chemical structures of lignin and cellulose. Treatment conditions, except for temperature, hardly changed the relationship between delignification rate and cellulose retention. During the treatment, dissolved lignin underwent chemical condensation in the aqueous phase. This “unfavorable” condensation consumed O2-derived active species, slowing down further delignification. Repeated short-time oxidation with renewal of alkaline water suppressed the condensation, enhancing the delignification. Repetition of 2-h treatments four times achieved 96% delignification, which was 8% higher than a single 8-h treatment at 130 °C.

Recent advances in the production of γ-valerolactone with liquid hydrogen source

Gamma(γ)-valerolactone (GVL) which can be produced from carbohydrate biomass has been regarded as one of the most promising platform chemicals because it can be converted to liquid alkenes adapted for transportation fuels. In the producing process, GVL was synthesized via hydrogenation of levulinic acid, which was obtained from acidic hydrolysis of carbohydrate biomass. Generally, gaseous hydrogen was employed as hydrogen source in the hydrogenation reaction. However, highly pure and high-pressure gaseous hydrogen faces high risk of hydrogen storage, transportation and operation. Moreover, due to the need for activating the gaseous hydrogen, noble metal catalysts were commonly used, limited the large-scale application. Some liquids, such as formic acid, alcohol and water, can act as hydrogen donor under cerain conditions. Liquid hydrogen source possesses safe and high efficiency advantages in the hydrogenation process. This paper highlights the recent progress in the production of GVL with liquid hydrogen source.

Electrosynthesis of Biobased Chemicals Using Carbohydrates as a Feedstock.

The current climate awareness coupled with increased focus on renewable energy and biobased chemicals have led to an increased demand for such biomass derived products. Electrosynthesis is a relatively new approach that allows a shift from conventional fossil-based chemistry towards a new model of a real sustainable chemistry that allows to use the excess renewable electricity to convert biobased feedstock into base and commodity chemicals. The electrosynthesis approach is expected to increase the production efficiency and minimize negative health for the workers and environmental impact all along the value chain. In this review, we discuss the various electrosynthesis approaches that have been applied on carbohydrate biomass specifically to produce valuable chemicals. The studies on the electro-oxidation of saccharides have mostly targeted the oxidation of the primary alcohol groups to form the corresponding uronic acids, with Au or TEMPO as the active electrocatalysts. The investigations on electroreduction of saccharides focused on the reduction of the aldehyde groups to the corresponding alcohols, using a variety of metal electrodes. Both oxidation and reduction pathways are elaborated here with most recent examples. Further recommendations have been made about the research needs, choice of electrocatalyst and electrolyte as well as upscaling the technology.

Depolymerization of holocellulose from Chinese herb residues by the mixture of lignin-derived deep eutectic solvent with water

The depolymerization of biomass carbohydrate polymers usually happened in homogeneous medium, just a few in heterogeneous solution. Herein, holocellulose from two Chinese herb residues Cortex albiziae (HRCA) and Heteropogon contortus (HRHC) was prepared and characterized. Deep eutectic solvent (DES) of choline chloride/p-coumaric acid collaborating with water was employed for the dissociation of those two holocelluloses and selectively dissolved hemicellulose into xylose with maximal yields of 81.50 % and 72.47 %, respectively. Most cellulose remained as the polymer state with a maximum solubility of 9.38 %. The synergistic action of DES and water was investigated to unveil the depolymerization mechanism and the roles of each component in depolymerizing procedure. It was water that released hemicellulose polymers and dissolved polymers to soluble short oligosaccharides, and DES rapidly cleaved the latter to xylose. Contrarily, DES broke cellulose to only soluble cello-oligosaccharides, but water exhibited the ability to hydrolyze cellulose to glucose.

Spirulina sp. LEB 18 cultivation in seawater and reduced nutrients: Bioprocess strategy for increasing carbohydrates in biomass

This study aimed to evaluate the growth and production of biomolecules by Spirulina sp. LEB 18 cultivated in seawater. The seawater was used without nutrient addition (SW0) and supplemented with 100% (SW100), 50% (SW50), and 25% (SW25) nitrogen, phosphorus, iron, and EDTA concentrations that make up the Zarrouk culture medium. When grown in SW0, Spirulina sp. LEB 18 showed maximum biomass concentration (2.17 g L−1) on the 11th d of cultivation and an increase in the carbohydrate content and productivity by 203% and 52%, respectively, when compared to the control culture. This cultivation strategy demonstrated the feasibility of using seawater as an alternative to freshwater in cultures as well as reduced nutritional requirements for biomass and carbohydrate production.

The synthesis of non-structural carbohydrates under the network security model

In order to explore the pathway of non-structural carbohydrate synthesis, an analysis of the pathway of non-structural carbohydrate synthesis under the network security model was proposed. Taking non-structural carbohydrates as the research object, the experimental materials and equipment were selected under the network security model. Through the establishment of detection methods, the preparation of freeze-dried carbohydrates, the influence of synthesis pathway-specific inhibitors on the synthesis of non-structural carbohydrates, the influence of precursors and intermediates in the pathway on the synthesis of non-structural carbohydrates, the effect of multiple factors on the synthesis of non-structural carbohydrates, the influence of polysaccharide synthesis, the treatment of reaction solution for detection, the preparation of detection sample, the detection conditions of a liquid phase, the detection conditions of LC-MS and the determination of carbohydrate biomass were studied. The results showed that the synthesis of nonstructural carbohydrates requires the participation of the glycolysis, shikimic acid and phenylpropane pathways, but not the polyketone pathway.

Catalytic Conversion of Carbohydrate Biomass in Ionic Liquids to 5-Hydroxymethyl Furfural and Levulinic Acid: A Review

The projections of ionic liquids as green solvents in chemical processes have increased in recent years. Ionic liquid is a versatile chemical with various applications. The aim of this review is to present a comprehensive perspective of ionic liquid for processing carbohydrate biomass by considering the recent progress in this field. Special attention is given to the application of ionic liquids for the production of 5-hydroxymethyl furfural (5-HMF) and levulinic acid (LA). Factors affecting the catalytic conversion of carbohydrate biomass in ionic liquid and the mechanisms of 5-HMF and LA production are also presented. In addition, the recyclability of the ionic liquid for carbohydrate biomass processing is discussed. The viewpoint for the application of functionalized ionic liquid as potential green solvent and catalyst is also highlighted. Future studies pertinent to carbohydrate biomass conversion in ionic liquids to 5-HMF and LA could use this review for selecting the appropriate reaction conditions required to achieve their specific goals. Besides, combination of technologies from ionic liquids and biomass processing strategies for the production of various fuels and value-added chemicals can be comprehended for applications in a lignocellulosic biorefinery.

Bioethanol production using the SSF method (simultaneous saccharification and fermentation) of microalgae anabaena sp.

Bioethanol is one of the alternative energy sources that answer the current energy crisis problems. The advantage of bioethanol compared to the fuel oil (BBM) is biodegradable. It contains an octane and high oxygen so it is flammable and reducing global warming emissions. Recently, the main ingredient of bioethanol has entered the third generation which is using microalgae. Anabaena sp. is one of the microalgae types from cyanobacteria which has the advantage of being used as bioethanol because it has carbohydrate biomass of about 20-30%. This research is aimed to produce bioethanol from microalgae Anabaena sp. The bioethanol production method used SSF because the advantage showed the converted polysaccharides into monosaccharides did not return to polysaccharides. It was caused monosaccharides directly fermented into ethanol. The use of one reactor reduced the cost of the process in the equipment used. This research was conducted in several stages, namely the preparation of raw materials, acid hydrolysis using H2SO4 1 M, and fermentation with the help of Saccharomyces cerevisiae microorganisms anaerobically. The results showed that using the SSF method was able to produce ethanol levels of 7%.

Composition analysis and minimal treatments to solubilize polysaccharides from the brown seaweed Laminaria digitata for microbial growth of thermophiles

Brown macroalgae (Phaeophyta) hold high potential as feedstock for biorefineries due to high biomass productivity and carbohydrate content. They are, however, a challenging, unconventional feedstock for microbial refining and several processing problems need to be solved to make them a viable option. Pre-treatment is necessary to enhance accessibility and solubility of the biomass components but should be minimal and mild to assure sustainable and cost-effective processing. Here, two routes to pre-treatLaminaria digitata to release polysaccharides were investigated: hot water pre-treatment by autoclaving (121 °C, 20 min or 60 min) and a two-step extraction with mild acid (0.1 M HCl) followed by alkaline treatment. Hot water pre-treatment resulted in partial extraction of a mixture of polysaccharides consisting of alginate, fucoidan and laminarin. After mild acid pre-treatment, alginate was found in the remaining insoluble residues and was extracted in a second step via alkaline treatment using Na2CO3 (0.15 M) at 80 °C and CaCl2 (10%) for the precipitation. In addition to carbohydrates, a fraction of other components such as proteins, phenolic compounds, minerals and trace elements was detected in the extracts. Cultivation of the thermophilic bacterial strains Rhodothermus marinus DSM 16675 and Bacillus methanolicus MGA3 (ATCC 53907) in media supplemented with the respective extracts resulted in growth of both strains, indicating that they were able to utilize the available carbon source for growth. R. marinus displayed the highest cell density in the medium containing the extract from acid pre-treatment, whereas B. methanolicus growth was highest with the extract from hot water pre-treatment.

Catalytic isomerization of d-glucose to d-fructose over BEA base zeotypes using different energy supply methods

The isomerization of d-glucose (Glu) to d-fructose (Fru) is a key step in the selective conversion of carbohydrate biomass to renewable products and has long been of great importance in the food and beverage industry. Expansion of the Fru market (food, non-food) poses various challenges to enhance productivity, where energy efficiency and use of cheap, robust synthetic catalysts may play important roles. Here, Glu isomerization, using water as the sole solvent, was studied using (i) micro/mesoporous catalysts of different compositions prepared from commercial zeolite Beta, and (ii) different energy supply methods, namely conventional conductive heating, microwave irradiation and ultrasound waves, at 75 °C. The type of energy supply method influenced the initial turnover frequency. Besides catalytic activity, the stability is important, which depended on the catalytic material properties (e.g., composition, textural properties), type of energy supply method and reaction temperature. Favourable results were verified for Glu isomerization using a hierarchical potassium/magnesium-containing Beta catalyst and ultrasound waves, at 75 °C.

Direct Conversion of Biomass Carbohydrates to Platform Chemicals: 5-Hydroxymethylfurfural (HMF) and Furfural

5-hydroxymethylfurfural (HMF) and furfural are promising platform molecules which can be converted to fuel intermediates and hydrocarbon fuels. Herein, one-step, direct conversion of the carbohydra...

Selection and characterization yeast potential from pineapple for bioethanol production using some sugar sources

Bioethanol can be produced through fermentation process of sugars based on carbohydrate biomass such as lignosellulosa by microorganism such as yeast. Yeast changes sugar as a carbon source to produce ethanol and CO2 in anaerobic condition. Pineapple as a fruit commodity that is widely cultivated in Indonesia contain high sugar and carbohydrates so it might contain yeast which has the potential in bioethanol production. This research aims to select and characterize potential yeast from pineapple for bioethanol production from some sugars. The method included fermentation test, ethanol production (measurement of reduction sugar, dry cell biomass, and ethanol contain), and molecular identification. Yeast utilize substrates as carbon source for producing cell or ethanol. Ethanol production influenced by substrates, microorganism, and total cell. The results showed that NHC3 used as selected isolate based on the degree of coloration in Oxidative Fermentative Media. The largest ethanol production was 10,63 g/L obtained from mannose where the highest value of substrate utilization efficiency was 95%. The value of yield product is 0,27 g bioethanol/g substrate and yield biomass is 0,14 g biomass/g substrate. BLAST result shows NHC3 had homology >99% with Saccharomycetales and Kodamaea ohmeri.

Recent progress in conversion of carbohydrate biomass and their derivatives to γ-valerolactone

Biomass, the only renewable resources of fixed carbon, shows great potential to ease the pressure on fossil energy crisis. In recent years, conversion of carbohydrate biomass into value-added products has been vastly reported. Gamma (γ)-valerolactone (GVL), which is one of the platform chemicals, has been extensively used in industrial production. Recent trends proposed an eco-friendly processing using water and biomass-derived materials as hydrogen sources instead of high-pressure and high-purity gaseous hydrogen, avoiding storage, transportation and operation risk in the production. This review summarizes the progress in GVL production from carbohydrate biomass and highlights the novel green approach by using green reductants and non-noble-metal catalysts.

Nitrogen immobilization may reduce invasibility of nutrient enriched plant community invaded by Phragmites australis

Nutrient enrichment, particularly nitrogen, is an important determinant of plant community productivity, diversity and invasibility in a wetland ecosystem. It may contribute to increasing colonization and dominance of invasive species, such as Phragmites australis, especially during wetland restoration. Providing native species a competitive advantage over invasive species, manipulating soil nutrients (nitrogen) may be an effective strategy to control the invasive species and that management tool is essential to restore the degraded ecosystems. Therefore, we examined competition between Phragmites australis and Melaleuca ericifolia in a greenhouse setting with activated carbon (AC) treatments, followed by cutting of Phragmites shoots in nutrient-rich soils. Additionally, we evaluated the effect of AC on plant-free microcosms in the laboratory, to differentiate direct effects of AC on soil microbial functions from indirect effects. Overall, the objective was to test whether lowering nitrogen might be an effective approach for reducing Phragmites invasion in the wetland. The AC reduced Phragmites total biomass more significantly in repeated cut regime (57%) of Phragmites shoots compared to uncut regime (39%). Conversely, it increased Melaleuca total biomass by 41% and 68% in uncut and repeated cut regimes, respectively. Additionally, AC decreased more total nitrogen in above-ground biomass (41 to 55%) and non-structural carbohydrate in rhizome (21 to 65%) of Phragmites, and less total nitrogen reduction in above-ground biomass (25 to 24%) of Melaleuca in repeated cut compared to uncut regime. The significant negative correlation between Phragmites and Melaleuca total biomass was observed, and noticed that Phragmites acquired less biomass comparatively than Melaleuca in AC-untreated versus AC-treated pots across the cutting frequency. AC also caused significant changes to microbial community functions across Phragmites populations, namely nitrogen mineralization, nitrification, nitrogen microbial biomass and dehydrogenase activity (P ≤ 0.05) that may potentially explain changes in plant growth competition between Phragmites and Melaleuca. The overall effects on plant growth, however, may be partially microbially mediated, which was demonstrated through soil microbial functions. Results support the idea that reducing community vulnerability to invasion through nutrient (nitrogen) manipulations by AC with reducing biomass of invasive species may provide an effective strategy for invasive species management and ecosystem restoration.

Влияние углеводного субстрата из крахмалсодержащего сырья на состав глюканов биомассы микромицета Aspergillus niger ВКПМ F-171

The conditions for biocatalytic cleavage of corn starch and rye whole grain flour for the subsequent cultivation of the Asperillus niger strain VKPM F-171 are described. As a result of this procedure, the amount of water-soluble carbohydrates in the substrates increased by 5-6 times in comparison with the initial raw material, and the content of glucan p-form in the hydrolysate of rye whole grain flour grew by 2-3 times. The content of glucans in the biomass by the end of the cultivation of A. niger VKPM F-171 on corn starch hydrolysate was 28±2% of dry matter, while the proportion of glucans after fermentation on the rye whole grain flour hydrolysate was 21±1%, 96-97% of which were β-glucans. The hydrolysis with Trichoderma longibrachiatum β-glucanase and Trichoderma reesei xylanase resulted in a 1.1-1.2-fold increase in the proportion of soluble carbohydrates in microbial biomass. It was found via gas-liquid chromatography that the structural units of carbohydrates in microbial biomass are represented by glucose and its 2- and 6-deoxy derivatives, fructose, fucose, galactose, mannose, xylose, and, to the greatest extent, by the reserve saccharide sedoheptulose. It was established that β-glucans are products of hydrolysis of the chitin-glucan complex and glycopeptides. The molecular weight of the obtained microbial glucan-containing biopolymers ranges from 0.5 to 50 kDa. It was shown that the content of β-glucans in microbial biomass allows the latter to be considered as an alternative to plant sources. biosynthesis, Asperillus niger, biocatalysis, starch-containing raw materials, glucans