Use In Biorefineries Research Articles

Variability of the chemical composition of Dendrocalamus giganteus in relation to growth stage

Bamboo is a renewable bioresource with extensive applications, from construction to textiles, and is essential for bioenergy and eco-friendly practices. Despite its potential use in biorefineries, the utilization of abundant species like Dendrocalamus giganteus is hindered by a lack of comprehensive knowledge regarding its chemical composition at various growth stages. In this study, we addressed this gap by quantifying the holocellulose, lignin and extractive contents of D. giganteus from the tropical forests of Bangladesh. We examined the composition across different ages and heights, assessing the solubility of holocellulose, lignin and extractive contents, with a view to enhance the use of D. giganteus in biorefinery industries. We analyzed chemical composition and assessed the solubility using both hot and cold water, as well as conducting 1 % NaOH (caustic soda) solubility tests following the TAPPI (Technical Association of the Pulp and Paper Industry) standards. The holocellulose, lignin, and extractive content increased with the increase age of the bamboo. These components also increased with increasing height, regardless of age. The solubility in water and NaOH, on the other hand, decreased with the increasing age and height positions. The top of 4-year-old bamboo exhibited the highest levels of holocellulose (70.2 %), lignin (29.7 %), and extractive components (6.9 %), but the lowest solubilities in hot water (6.18 %), cold water (3.58 %) and caustic soda (22.48 %). These findings suggest that D. giganteus has potential applications in specific industries, such as pulp and paper, nanocellulose, bioethanol, biochemicals and bio-based composites.

Spondias tuberosa and Spondias mombin: Nutritional Composition, Bioactive Compounds, Biological Activity and Technological Applications

The genus Spondias has two species of native trees from Brazil that deserve to be highlighted: Spondias tuberosa (“umbu”) and Spondias mombin (“cajá”). Their fruit contain bioactive compounds which have been associated with several biological activities. However, they remain little exploited in the development of food and pharmaceutical products. In this perspective, the present review summarizes the literature data about the physicochemical and nutritional characteristics, bioactive compounds, potential health benefits, and industrial applications of these fruit, including their pulp, seed, and peel. The current scenery mapping for scientific articles was performed in the Scopus and Web of Science databases. The study also considered patent applications collected in the Derwent database. Results showed an increase in scientific publications in recent years for both species. Many applications are related to food technology; nevertheless, due to the composition of their non-edible fractions, they have the potential for use in biorefinery, being their use an opportunity for bioeconomy. Thus, this review provides a comprehensive overview of these Brazilian native fruit to offer a theoretical foundation and valuable data for future investigations and exploitation.

Design of an integrated biorefinery for bioethylene production from industrial forest byproducts

We identified the significant technical-economic factors, uncertainty, and risks in the pine sawdust biorefinery design for bioethylene and lignin production.

Catalytic hydrolysis of agar using magnetic nanoparticles: optimization and characterization

BackgroundAgar is used as a gelling agent that possesses a variety of biological properties; it consists of the polysaccharides agarose and porphyrin. In addition, the monomeric sugars generated after agar hydrolysis can be functionalized for use in biorefineries and biofuel production. The main objective of this study was to develop a sustainable agar hydrolysis process for bioethanol production using nanotechnology. Peroxidase-mimicking Fe3O4-MNPs were applied for agar degradation to generate agar hydrolysate-soluble fractions amenable to Saccharomyces cerevisiae and Escherichia coli during fermentation.ResultsFe3O4-MNP-treated (Fe3O4-MNPs, 1 g/L) agar exhibited 0.903 g/L of reducing sugar, which was 21-fold higher than that of the control (without Fe3O4-MNP-treated). Approximately 0.0181% and 0.0042% of ethanol from 1% of agar was achieved using Saccharomyces cerevisiae and Escherichia coli, respectively, after process optimization. Furthermore, different analytical techniques (FTIR, SEM, TEM, EDS, XRD, and TGA) were applied to validate the efficiency of Fe3O4-MNPs in agar degradation.ConclusionsTo the best of our knowledge, Fe3O4-MNP-treated agar degradation for bioethanol production through process optimization is a simpler, easier, and novel method for commercialization.

The National and Regional Impact of the EU Bioeconomy Strategies on the Agri-Food Sector: Insights from Germany

The bioeconomy strategy of the European Union aims to balance three distinct goals: food security, the sustainable use of renewable resources for industrial purposes, and environmental protection. This study uses an integrated computable general equilibrium model to simulate the impacts of selected elements of the EU bioeconomy strategy on German agriculture at national and regional level up to 2050. An improved productivity of the crop sector substantially increases production and export/import ratio of crop outputs and reduces crop prices, while only moderately expanding cropland. The improved crop productivity would help to reduce the competition for resources between non-food and food biomass use as well as between crop and livestock production. An increasing conversion efficiency of agricultural biomass for use in biorefineries alone is unlikely to have a significant impact on the German bioeconomy. Overall, the results suggest the need for further efforts to improve crop productivity and effective complementary measures supporting the development of transformative technologies and changes in consumer preferences to ensure a minimum level of biomass use in the chemical sector.

Analysis of Single-Step Pretreatments for Lignocellulosic Platform Isolation as the Basis of Biorefinery Design.

Biorefinery feasibility is highly influenced by the early design of the best feedstock transformation pathway to obtain value-added products. Pretreatment has been identified as the critical stage in biorefinery design since proper pretreatment influences subsequent reaction, separation, and purification processes. However, many pretreatment analyses have focused on preserving and valorizing six-carbon sugars for future use in bioconversion processes, leaving aside fractions such as hemicellulose and lignin. To date, there has been no pretreatment systematization for the removal of lignocellulosic fractions. This work defines pretreatment efficacy through operational, economic, environmental, and social indicators. Thus, using the data reported in the literature, as well as the results of the simulation schemes, a multi-criteria weighting of the best-performing schemes for the isolation or removal of cellulose, hemicellulose, and lignin was carried out. As a main result, it was concluded that dilute acid is the most effective for cellulose isolation and hemicellulose removal for producing platform products based on six- and five-carbon sugars, respectively. Additionally, the kraft process is the best methodology for lignin removal and its future use in biorefineries. The results of this work help to elucidate a methodological systematization of the pretreatment efficacy in the design of biorefineries as an early feasibility stage considering sustainability aspects.

Nepenthes mirabilis Fractionated Pitcher Fluid Use for Mixed Agro-Waste Pretreatment: Advocacy for Non-Chemical Use in Biorefineries

This study determined whether it is feasible to pretreat mixed agro-waste of different particle sizes using the pitcher fluid of Nepenthes mirabilis (N. mirabilis), which is known to digest leaf litter due to the enzyme cocktail contained in the fluid. This is due to the need for the holocellulolysis (a source of fermentable sugars) of mixed agro-waste to produce fermentable hydrolysates. The pitcher fluid was fractionated (<3 kDa, >3 kDa, <10 kDa, >10 kDa) and slurrified with the mixed agro-waste, i.e., 25% (w/w) for each waste—orange peels, apple peels, maize cobs, grape pomace, and oak plant leaf litter of various particle sizes, i.e., >75 µm x < 106 µm and >106 µm. The process of producing a high concentration of total reducible sugars (TRSs) with the lowest production of total phenolic compounds (TPCs) was determined to be a particle size of >106 µm, pretreatment for 72 h, and an enzyme fraction of <10 kDa, whereby 97 g/L of TRSs were produced with a significantly lower TPCs load (1 g/L). Furthermore, the <10 kDa showed preferable physico-chemical properties, with the highest reduction-oxidation potential including acidity. Several enzymes, i.e., β-1,3-Glucanase, Putative peroxidase 27, Thaumatin-like protein, among others, were identified in the <10 kDa fraction, i.e., enzymes known to perform various functions in plant-based waste. Therefore, there is a need for the renewable energy industry to consider solely using pitcher fluids to pretreat mixed agro-waste for fermentable hydrolysates’ production, which can be used as liquid feedstock for the bioenergy and/or biorefinery industries for environmental pollution reduction.

Growth of Methylobacterium organophilum in Methanol for the Simultaneous Production of Single-Cell Protein and Metabolites of Interest.

This study aims to monitor the growth of the methylotrophic bacteria Methylobacterium organophilum in a culture medium with methanol as a carbon source and to verify the production of unicellular proteins and other biomolecules, such as carotenoids, exopolysaccharides and polyhydroxyalkanoates, making them more attractive as animal feed. Bacterial growth was studied in shake flasks using different carbon/nitrogen (C:N) ratios to determine their best ratio for achieving the highest volumetric productivity of cells and substrate consumption rate. This optimal parameter was further used in a fed-batch operating bioreactor system to define the kinetic profile of cell growth. Methanol consumption was measured by HPLC analysis and the extracted pigments were analyzed by liquid chromatography/mass spectrometry. Chemical composition and rheological properties of the produced exopolysaccharides were also determined. The best experimental parameters were verified using an initial methanol concentration of 7 g/L in the culture medium. The same initial substrate concentration was used in the fed-batch operation and after 60 h of cultivation 5 g/L of biomass were obtained. The accumulation of carotenoids associated with cell growth was monitored, reaching a concentration of 1.6 mg/L at the end of the process. These pigments were then analyzed and characterized as a set of xanthophylls (oxidized carotenoids). In addition, two other product types were identified during the fed-batch operation: exopolysaccharides, which reached a concentration of 8.9 g/L at the end of the cultivation, and an intracellular granular structure that was detected by transmission electron microscopy (TEM), suggesting the accumulation of polyhydroxyalkanoate (PHA), most likely polyhydroxybutyrate. Methylobacterium organophilum demonstrated a unique ability to produce compounds of commercial interest. The distinct metabolic diversity of this bacterium makes room for its use in biorefineries.

Climate change affects cell‐wall structure and hydrolytic performance of a perennial grass as an energy crop

AbstractPerennial grasses, such as Panicum maximum, are important alternatives to dedicated energy crops for bioethanol production. This study investigates whether future climate conditions could influence P. maximum cell‐wall structure and hydrolytic performance. To analyze interactions with environmental factors in field conditions, a combined Free‐air Temperature and CO2 Controlled Enhancement (Trop‐T‐FACE) facility was used to investigate the isolated and combined effect of elevated atmospheric CO2 concentration (eC) (600 μmol.mol−1) and elevated temperature (eT) by 2 °C more than the ambient temperature, on cell‐wall composition, cellulose crystallinity, accessibility, and hydrolysis yields. The elevated temperature treatments (eT and eT + eC) exhibited the most pronounced effects on the P. maximum cell wall. Warming reduced the starch content and the crystallinity index (CI) of cellulose and increased the cellulose content. Fluorescent protein‐tagged carbohydrate‐binding modules analysis demonstrated that warming improved total cellulose surface exposure/accessibility in eT and eT + eC by 181% and 132%, respectively. Consequently, glucan conversion yields were improved by 7.07% and 5.37%, showing that warming led to lower recalcitrance in P. maximum biomass, which positively affects its use in biorefineries. This work therefore provides important information from an ecological and economic point of view, allowing us to understand the mitigation process applied by this forage grass under future climate conditions. It might assist in selecting tropical forage grasses that are efficiently adapted to climate change, with a positive effect on bioenergy production. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

Towards a Cardoon (Cynara cardunculus var. altilis)-Based Biorefinery: A Case Study of Improved Cell Cultures via Genetic Modulation of the Phenylpropanoid Pathway.

Cultivated cardoon (Cynara cardunculus var. altilis L.) is a promising candidate species for the development of plant cell cultures suitable for large-scale biomass production and recovery of nutraceuticals. We set up a protocol for Agrobacterium tumefaciens-mediated transformation, which can be used for the improvement of cardoon cell cultures in a frame of biorefinery. As high lignin content determines lower saccharification yields for the biomass, we opted for a biotechnological approach, with the purpose of reducing lignin content; we generated transgenic lines overexpressing the Arabidopsis thaliana MYB4 transcription factor, a known repressor of lignin/flavonoid biosynthesis. Here, we report a comprehensive characterization, including metabolic and transcriptomic analyses of AtMYB4 overexpression cardoon lines, in comparison to wild type, underlining favorable traits for their use in biorefinery. Among these, the improved accessibility of the lignocellulosic biomass to degrading enzymes due to depletion of lignin content, the unexpected increased growth rates, and the valuable nutraceutical profiles, in particular for hydroxycinnamic/caffeoylquinic and fatty acids profiles.

Evaluation of passiflora edulis flavicarpa and dioscorea spp. peelings as potential raw material for biorefineries

The use of agro-industrial residues in biorefinery processes has been increasing due to the negative environmental impact associated with the excessive use of fossil fuels. Several residues have been evaluated as precursors for carbohydrate production, which in turn can be converted into numerous high value-added products, such as the products of the furanic series, 5-hydroxymethylfurfural and furfural. Thus, this work aimed to determine the chemical composition of passion fruit and purple yam peels in order to analyze their potential for use as raw material for biorefineries. For the determination of sugars, the shells were submitted to acid hydrolysis according to two different methodologies: one by the National Renewable Energy Laboratory method and the other by the Dunning et al. (1949) methodology. The products obtained were analyzed by Fourier Transform Infrared Spectrophotometry and High-Performance Liquid Chromatography. The results show that passion fruit and purple yam peels presented high percentages of hemicellulose (30% and 15%, respectively) and mainly of cellulose (above 44% for both shells according to the two tested methodologies). Due to the significant amount of these polysaccharides present in the biomass, they have potential for use in biorefineries.

Tequila Still Distillation Fractioned Residual Streams for Use in Biorefinery

Tequila vinasses is a mixture made from up to six still distillation two-stage process residual effluents. First stage fractions: residual must (60%), heads (0.9%) and tails (20.0%); second stage fractions: non-evaporated (8.0%), heads (0.1%) and tails (1.0%); the result is a more complex effluent for its treatment or biorefining. The objectives of this study were to: (a) characterize the five still distillation volatile streams in the Tequila 100% Agave processing; compounds: methanol, ethanol, acetaldehyde, ethyl acetate, sec-butanol, n-propanol, iso-butanol, n-butanol, iso-amyl, n-amyl, and ethyl lactate were detected by gas chromatography; calculated chemical oxygen demand from chemical composition had very high values (53,760–1,239,220 mg/L); measurement of pH (3.24–4.80), color (38.6 UC Pt-Co max), turbidity (46.1 max), electrical conductivity (3.30–172.20 μS/cm), and solid content (0 mg/L) was also made; (b) report an energy analysis (2.02 × 109 KWh) and CO2 production (429 × 106 kg) in the Tequila industry during 2019; (c) up to date residues (365.2 × 106 kg agave bagasse, 1146.1 × 106 kg agave leaves and 3300.0 × 106 L agave vinasse) in 2019; (d) economic analysis, current tequila vinasses treatment price is 16.00 USD/m3 but could reach a considerable fraction value if is bio-refined, a break down component analysis reach for five volatile streams $51.23–$140.00 USD/m3.

Evaluation of residual biomass produced in Cerrado Tocantinense as potential raw biomass for biorefinery

Furanic compounds such as 5-hydroxymethylfurfural (HMF) and furfural (FF) obtained from biomass have emerged as important industrial chemical platforms. In this sense, the present study aimed to evaluate the economical use of crude biomass of rice husk (RH), cupuacu peel (CP), and pequi peel (PP) to obtain furanic compounds such as HMF and FF, using the ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]) and the catalyst chromium(III) chloride hexahydrate (CrCl3.6H2O). The results of the analysis showed that biomasses have potential for use in biorefineries; however, the most promising among those is the RH, due to the significant content of holocellulose. The optimization of hydrolysis through the methodology developed by Dunning and Dallas (1949) made it possible to obtain significant levels of glucose (14.28%), xylose (3.81%), and arabinose (0.93%). The obtained products were analyzed by Fourier transform infrared spectrophotometry (FT-IR) and high-performance liquid chromatography (HPLC). The best yields for RH obtained were 1.92% (HMF) and 2.89% (FF). From the results obtained, it can be concluded that the RH has a good capacity for producing value-added compounds in biorefineries.

JERUSALEM ARTICHOKE (HELIANTHUS TUBEROSUS L.) AS ENERGY RAW MATERIAL

Jerusalem artichoke is suitable for use in biorefineries due to the very high biomass production and low soil, climate and cultivation requirements. Tubers of this species can be used for the production of methane fermentation or bioethanol. The aboveground part can be used for the production of biomethane, as well as in the direct combustion process or for the production of briquettes and pellets. Of the cultivars tested, Albik and Violet de Rennes proved to be the most useful for energy purposes. An important advantage of Jerusalem artichoke is its resistance to adverse climatic conditions (drought, frost), resistance to diseases and pests and the possibility of self-renewal.

HTC of Wet Residues of the Brewing Process: Comprehensive Characterization of Produced Beer, Spent Grain and Valorized Residues

Steady consumption of beer results in a steady output of residues, i.e., brewer’s spent grain (BSG). Its valorization, using hydrothermal carbonization (HTC) seems sensible. However, a significant knowledge gap regarding the variability of this residue and its influence on the valorization process and its potential use in biorefineries exists. This study attempted to fill this gap by characterization of BSG in conjunction with the main product (beer), taking into accounts details of the brewing process. Moreover, different methods to assess the performance of HTC were investigated. Overall, the differences in terms of the fuel properties of both types of spent grain were much less stark, in comparison to the differences between the respective beers. The use of HTC as a pretreatment of BSG for subsequent use as a biorefinery feedstock can be considered beneficial. HTC was helpful in uniformization and improvement of the fuel properties. A significant decrease in the oxygen content and O/C ratio and improved grindability was achieved. The Weber method proved to be feasible for HTC productivity assessment for commercial installations, giving satisfactory results for most of the cases, contrary to traditional ash tracer method, which resulted in significant overestimations of the mass yield.

Breeding for dual-purpose wheat varieties using marker-trait associations for biomass yield and quality traits.

This study demonstrates that an active breeding nursery with rotation can be used to identify marker-trait associations for biomass yield and quality parameters that are important for biorefinery purposes. Wheat straw is a valuable feedstock for bioethanol production, but due to the recalcitrant nature of lignocellulose, its efficient use in biorefineries is limited by its low digestibility and difficult conversion of structural carbohydrates into free sugars. A genome-wide association study (GWAS) was conducted to search for significant SNP markers that could be used in a breeding programme to improve the value of wheat straw in a biorefinery setting. As part of a 3-year breeding programme (2013-2016), 190 winter wheat lines were phenotyped for traits that affect the yield and quality of the harvested biomass. These traits included straw yield, plant height, lodging at three growth stages and Septoria tritici blotch (STB) susceptibility. Release of glucose, xylose and arabinose was determined after hydrothermal pretreatment and enzymatic hydrolysis of the straw. The lines were genotyped using 15K SNP markers and 5552 SNP markers could be used after filtering. Heritability for all traits ranged from 0.02 to 0.74. GWASs were conducted using CMLM, SUPER and FarmCPU algorithms, to analyse which algorithm could detect the highest number of marker-trait associations (MTAs). Comparable tendencies were obtained from CMLM and FarmCPU, but FarmCPU produced the most significant results. MTAs were obtained for lodging, harvest index, plant height, STB, glucose, xylose and arabinose at a significance level of p < 9.01 × 10-6. MTAs in chromosome 6A were observed for glucose, xylose and arabinose, and could be of importance for increasing sugar release for bioethanol production.

Biorefinery review: Wide-reaching products through kraft lignin

This review details the structure of lignin and curates information on the characteristics that this polymer must have for each specific use. Lignin is a by-product of the pulp and paper industry and the second most abundant biopolymer after cellulose. Approximately 50 million tons of lignin are produced worldwide annually, of which 98% to 99% is incinerated to produce steam, process energy. Just 1% to 2% of the lignin, derived from the sulfite pulp industry, is used in chemical conversion to produce lignosulfonates. Biorefining is a promising approach to promote the wider use of kraft lignin. However, using kraft lignin to produce high value-added products is a great challenge, due to its complex structure, low reactivity, and low solubility, which are factors that limit the lignin’s large-scale use in biorefineries. Recent studies show that kraft lignin can be used as lignosulfonates and dispersants, technical carbons, transportation fuels, bioplastics, and adhesives, but some technological hurdles must be overcome and several industrial tests must be developed to make these uses viable.

Separation of BTX chemicals from biomass pyrolysis oils via continuous flash distillation

Partially deoxygenated pyrolysis oils, such as those produced by tail gas reactive pyrolysis (TGRP), show promise for use in biorefineries if they can integrate into standard refinery operations, one of which is distillation. A feasible method for modeling the process and for removing aqueous components will advance progress. This study investigated the potential of continuous flash distillation for fractionating partially deoxygenated bio-oil component chemicals benzene, toluene, and xylene (BTX), which are critical feedstocks for producing many refinery products. A model bio-oil mixture was used to evaluate process performance, and process conditions were investigated with respect to separation efficiency (temperature = 120, 130, and 140 °C; input flow rate = 2 or 3 mL min−1). Mean BTX yield (gout gin−1) for an oil flow rate of 2 mL min−1 ranged between 0.134 and 0.222 gout gin−1, while for 3 mL min−1 yields ranged from 0.135 to 0.400 gout gin−1. In all treatments, the measured amounts of BTX from model bio-oil were less than those from ASPEN simulations. From the distillates, aqueous fractions phase separated while sequestering acetic acid from the organics. Residence time within the drum was positively correlated with concentration of BTX in the distillates. At no point did solid residues form within the flash drum. When compared with analogous experiments at optimal conditions, BTX yields from real TGRP oil were comparable but less than the analogous model experiment. These results suggest that continuous, atmospheric pressure distillation of low-oxygen bio-oils can be used for separating commodity, refinery-grade chemicals such as BTX from biomass pyrolysis-derived bio-oils.

AA16, a new lytic polysaccharide monooxygenase family identified in fungal secretomes

BackgroundLignocellulosic biomass is considered as a promising alternative to fossil resources for the production of fuels, materials and chemicals. Efficient enzymatic systems are needed to degrade the plant cell wall and overcome its recalcitrance. A widely used producer of cellulolytic cocktails is the ascomycete Trichoderma reesei, but this organism secretes a limited set of enzymes. To improve the saccharification yields, one strategy is to upgrade the T. reesei enzyme cocktail with enzymes produced by other biomass-degrading filamentous fungi isolated from biodiversity.ResultsIn this study, the enzymatic cocktails secreted by five strains from the genus Aspergillus (Aspergillus japonicus strains BRFM 405, 1487, 1489, 1490 and Aspergillus niger strain BRFM 430) were tested for their ability to boost a T. reesei reference cocktail for the saccharification of pretreated biomass. Proteomic analysis of fungal secretomes that significantly improved biomass degradation showed that the presence of proteins belonging to a putative LPMO family previously identified by genome analysis and awaiting experimental demonstration of activity. Members of this novel LPMO family, named AA16, are encountered in fungi and oomycetes with life styles oriented toward interactions with plant biomass. One AA16 protein from Aspergillus aculeatus (AaAA16) was produced to high level in Pichia pastoris. LPMO-type enzyme activity was demonstrated on cellulose with oxidative cleavage at the C1 position of the glucose unit. AaAA16 LPMO was found to significantly improve the activity of T. reesei CBHI on cellulosic substrates.ConclusionsAlthough Aspergillus spp. has been investigated for decades for their CAZymes diversity, we identified members of a new fungal LPMO family using secretomics and functional assays. Properties of the founding member of the AA16 family characterized herein could be of interest for use in biorefineries.

Analysis of Animal Bedding Heterogeneity for Potential Use in Biorefineries Based on Farmyard Manure

PurposeAnimal bedding, a mixture of straw and manure, could be used as a feedstock for bioenergy production, but its heterogeneity poses new challenges in its use in biorefineries. We have investigated the origin of this heterogeneity and quantified it, and discuss its impact on bioenergy production.MethodsSamples were collected from the bedding at different points and depths and analysed by first separating the manure from the straw by means of washing with water, and then determining the chemical composition of the liquid and solid fractions.ResultsThe results supported our hypothesis that animal bedding behaves as a combination of several layers at different stages of degradation. Analysis revealed that the layers with higher organic content in the manure exhibited a poorer performance during the washing, since the residence time in the barn alters the washing profile of the organic fraction in the manure. It was also found that the variability in the composition of animal bedding was much greater than in other agricultural feedstocks: the manure content in animal bedding varied from 26 to 41%, and the content of fermentable carbohydrates varied by 20%. Total carbon and total nitrogen analyses showed that these changes in composition also affected the C/N ratio of the material, and thus its suitability as a feedstock for anaerobic digestion.ConclusionsThis implies that the residence time in the barn affects not only the heterogeneity of the properties of animal bedding, but also the best way to process it in a biorefinery.