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•Multistage SFE and ASE extraction yields are comparable.•Subcritical CO2 yields 41% of the extractable bark: 32% are unsaturated fatty acids.•Increasing density at constant ...temperature rises recovery of wax and sterol esters.•Increasing temperature at constant pressure enhances resin acids solubility.•Using ethanol as co-solvent obtains 50% of extract composed by phenolics.
Multistage fractionation of pine bark was performed using subcritical and supercritical CO2 at increasing pressures and temperatures. In total, seven fractions were collected, which demonstrated different enrichments of families of compounds. In particular, subcritical CO2 yielded 41% of the total extract in which unsaturated fatty acids represented the most abundant family. The subsequent five supercritical steps increased the recovery of sterol esters, wax esters and resin acids at higher temperatures and pressures, reaching 80% of the total extractable mass. In the last step, using ethanol as a co-solvent, an additional 20% of extract was recovered, which was enriched with phenolics and glycerol. A full characterisation of the extracts was accomplished by high-temperature GC–MS/FID using four internal standards, which were representative of the main classes of compounds contained in the pine bark extract.
Background.
The technology of deep grain processing is based on the use of operations that ensure separation of raw materials into various components and sequential processing of these components ...into products of high consumer value. The annual volume of deep grain processing products is over 100 million tons. Starch, as the most valuable component of processed grain, is used in the food industry, pharmacy, and in significant amounts for technical purposes. Studying the potential of domestic maize hybrids to provide raw materials for deep grain processing enterprises is a relevant task.
Materials and methods.
The material for field and laboratory studies included 17 commercial maize hybrids developed at the P.P. Lukyanenko National Grain Center. The content of starch, protein and oil in grain was measured with infrared spectroscopy on an Infratec 1241 Grain Analyzer. Actual extraction of native starch was implemented using the “plant-on-the-table” method developed at the All-Russian Research Institute of Starch Products, and breeding trials of maize hybrids were carried out in the steppe zone of Kabardino-Balkaria in 2020/2021.
Results.
As a result of the research, 13 hybrids with a mass fraction of starch in the range of 70.0–73.2% DM were identified: KR210MV, KR270MV, KR377AMV, KR385MV, KR415MV, ROSS198MV, KR433MV, KR514MV, KR575MV, LYUDMILA, ROSS190MV, and ROSS195MV. Of these, the grain yield in the range of 10–14 t/ha was shown by the hybrids KR270MV, KR315MV, KR377AMV, KR415MV, KR514MV, and KR575MV. In accordance with the results obtained, a number of hybrids can be recommended as source material for breeding and promising raw material for deep grain processing: KR415MV, KR393MV, and ROSS198MV, yielding 90.0–94.4% DW of starch when processed, and KR315MV, with a mass fraction of amylose in starch up to 38.6% DW.
•The losses of condensed tannins remained low with temperatures not exceeding 50 °C.•Total dissolved solids decreased by 10–24 % during 26–34 -h drying schemes.•Stilbene losses up to 60 % were found; ...most of them occurred in the first 10 h.
Norway spruce (Picea abies (L.) Karst.) bark contains marked amounts of polyphenolic compounds. Condensed tannins (CTs) and stilbenes show commercial potential as antioxidants, antimicrobials, preservatives in food and cosmetic applications, technochemical products, and pharmaceuticals. Storing of bark before the conversion process leads to substantial losses of extractives compounds. In the present study, the potential of thermal drying for maintaining extractives content was assessed based on an experiment in which bark samples were dried in convection kilns at 40, 50, 60, and 70 °C temperatures. The development of CTs and stilbene contents and CT degradation were followed for 28–34 h. CTs were analysed from bark samples with thiolysis. Quantities of stilbene glycosides and stilbene aglycones in water-acetone extracts were analysed applying gas chromatography with flame-ionization detection (GC-FID). Multilevel regression analysis was used to analyse the statistical differences in moisture content and extractives composition between the drying schemes.
The initial CT content of 35–36 mg g−1 in dry bark material declined to 25–31 mg g-1 in 28–34 h. The average degree of polymerisation (DP) decreased slightly, and the relative proportion of prodelphinidins in CTs increased significantly in the 60 and 70 °C schemes. The proportion of A-type linkages slightly increased with the increase in drying temperature. The initial mean stilbene contents varied from 19 mg g−1 to 22 mg g−1 in dry bark mass. Isorhapontin was the major stilbene constituent, with a proportion of 45–49 % of the total stilbenes. Stilbene losses of up to 60 % were detected during the drying processes. In 10 h, for example, 36–43 % of total stilbenes were lost. Degradation activities by enzymes released from the bark and oxidative reactions after crushing at the debarking phase were concluded to be the primary mode of degradation. The results indicate that bark CT content can be preserved at a moderate temperature not exceeding 50 °C, but the degradation of CTs may affect their suitability for various applications. Sufficient stilbene content for industrial processes is unlikely to be maintainable through thermal drying. The permanence of the post-drying extractives content should be assessed based on a practical-scale storage experiment using bark dried to varying moisture contents.
Se realizó un análisis para determinar los principales componentes químicos de la madera de tres cabezas de vigas de pino procedentes del área de archivo del edificio histórico conocido como La ...Mitra, de la ciudad de Morelia, en Michoacán, México. Este análisis es complementario a uno previamente realizado, por medio de ultrasonido y con fines de conservación y restauración de estructuras de carácter histórico. Las vigas que aquí se analizaron forman parte del grupo que se estudió en esa primera fase; seleccionadas de forma aleatoria de un grupo de 40 y con dimensiones de 25 cm × 17 cm × 60 cm. Se tomaron muestras de albura y de duramen en dos secciones distintas (zona de empotramiento deteriorada y sana). Para cada viga se determinaron valores de pH, cenizas, análisis de las cenizas, sustancias extraíbles, holocelulosa y lignina. Los resultados encontrados fueron: pH de 3.20 a 4.67, cenizas 0.25% a 1.36%, con mayor concentración de oxígeno (3.36% a 6.64%), calcio (1.80% a 3.46%), carbono (1.18% a 3.45%), potasio (0.20% a 0.84%), aluminio (0.17 % a 0.31%), silicio (0.15% a 0.59%) y magnesio (0.15% a 0.56%); solubilidad en sosa de (9.83% a 27.78%), extraíbles totales, en la extracción secuencial, la mayor solubilidad se obtuvo con acetona, (2.92% a 6.96%), seguido de agua caliente (0.25% a 7.49%), metanol (2.03% a 6.22%) y ciclohexano (0.98% a 2.66%); holocelulosa (68.22% a 84.01%) y lignina (24.19% a 31.83%). El pH, la solubilidad en sosa, la holocelulosa y la lignina presentaron una variación estadística significativa (P < 0,05) entre albura y duramen de las zonas sanas y deterioradas.
The studies carried out on biomass pyrolysis indicate that cellulose, hemicellulose, and lignin are solely responsible for the chemical composition of bio-oil. However, few studies refer to ...extractives as a relatively significant biomass fraction in bio-oil composition. This work aims to study the influence of hydrophilic extractives on the quality of bio-oil using sugar cane bagasse, sisal, and eucalyptus bark residue. The extractives were separated from the biomasses, using ethanol and water as solvents due to their polarity and efficiency in extracting hydrophilic compounds. Three materials were obtained: biomass before and after extraction and extractives. GC-MS was used to identify the species that compose the extractives and the micro-pyrolysis products at 550°C of the three materials. As expected, the results showed that the bio-oils had different compositions. While bio-oils derived from sugarcane bagasse and eucalyptus bark residue exhibited higher levels of aldehydes (23%), bio-oil from sisal residue contained approximately 47% hydrocarbons. Finally, extractives also influenced CO2 production, as evidenced by notable variations in the range of 52.6–75.3% of this compound during the pyrolysis of biomass extractives. These differences are especially notable in biomasses with higher extractive contents, such as sisal (69.3%) and eucalyptus bark (21.9%) residues.
•Study of extractives in bio-oils from sugarcane bagasse, sisal, and eucalyptus bark.•Sisal stands out in its likely applicability for vehicle fuel.•Sugarcane and eucalyptus bark residues have uses in the chemical and pharmaceutical industry.•The bio-oil derived from sisal residue exhibited 47% hydrocarbons.
Herein, we report a multistep synthesis of novel (meth)acrylate monomers based on gallic acid (GA), a biosourced phenolic acid. The objective of this work was to obtain bio-based polymers exhibiting ...antioxidant properties provided by monomers derived from gallic acid. The phenolic groups of GA, which are responsible for antioxidant properties, need to be protected for two reasons. On the one hand, functionalization to transform GA into polymerizable monomers must not take place at the phenolic groups because they must remain free to maintain the maximum antioxidant activity in the final polymers. On the other hand, their protection is necessary to prevent radical scavenging during the radical polymerization. After synthesis of such monomers, protected GA-based polymers were thus produced through a photo-mediated RAFT polymerization at room temperature by evaluating two trithiocarbonate-type chain transfer agents (CTAs). The kinetics and molecular weight distributions were studied depending on the monomers and the CTAs. Protected polymers were then deprotected to afford polymeric chains carrying one free gallic acid moiety on each monomer unit. The antioxidant activity of these free GA-based polymers was demonstrated either through the DPPH free radical scavenging property or through the inhibition of methyl linoleate oxidation.
This article investigates the intersection of three interrelated trends: first, the positioning of sport as a contributor to sustainable development, particularly in regard to the increasing ...corporatization of sport for development (SFD); second, the trend toward sustainable development in the extractives industry, as taken up within a corporate social responsibility (CSR) approach; and third, the intersection of SFD and CSR when mobilized in pursuit of sustainable development in Indigenous communities in Canada. To do so, we examined the sustainability documents of Rio Tinto, the largest mining and metals company in Canada, with a focus on its operations in the Canadian North that are near Indigenous communities. Based on our results, we argue that SFD programming and the CSR approaches of Rio Tinto promote forms of sustainable development that capitalize on broadened (and emptied) definitions of sustainability, which may ultimately contribute to greater forms of unsustainability.
This paper discusses the research activities done at Politecnico di Milano in the field of the detailed kinetic modeling of pyrolysis and combustion of biomass and bio-oil formation. Different ...critical steps are involved in this multicomponent, multiphase and multiscale problem. The first complexity relies on biomass characterization with the selection of reference species: cellulose, hemicellulose, lignins, and extractives. Fast pyrolysis involves kinetic mechanisms, first in the solid phase for biomass pyrolysis, then in gas-phase for secondary reactions of released products. These mechanisms involve large number of species and reactions, which make computations expensive. They need to be simplified, while still maintaining their description capability. Lumping procedures are extensively applied to allow the development of the overall model. Multistep pyrolysis mechanisms of reference species are discussed in this Note, with several comparisons with experimental data. A peculiarity of the model is its ability to provide detailed compositions of pyrolysis products and solid residue. Catalytic effect of ash on pyrolysis products is also discussed. A companion paper will discuss the successive or secondary gas phase reactions of pyrolysis products, together with the heterogeneous reactions of residual char. Finally, the modeling of bio-oil formation requires a comprehensive description of the coupling of kinetic and transport processes, both at the particle and the reactor scale.
The objective of this study was to investigate the effects of waxy extract of Spilanthes acmella and essential oil (EO) of Nectandra grandiflora on secondary stress responses of tambaqui Colossoma ...macropomum transported for up to 10 h. Fish were packed in plastic bags and shipped for 2, 6 and 10 h with or without anaesthetics added to the transport water. Whole blood was collected from the caudal vasculature before and after transport and several haematological variables were measured. No mortalities were observed after transport. Attenuation of secondary stress responses was observed with the use of N. grandiflora EO after 6 h transport based on lower glycaemia and no alteration of blood Na+ concentrations after transport compared to reference values of non-transported fish. Furthermore, dissolved oxygen levels were still maintained in the water after transport for 10 h with N. grandiflora EO compared to water of non-transported fish. While no clear advantages were observed with the use of S. acmella extract at 2 mg L−1 after transport, the use of N. grandiflora EO at 30 μL L−1 should be considered for the transport of C. macropomum for it seems to provide a sparing effect on the water dissolved oxygen levels and an improved physiological condition after transport.
•Essential oil of Nectandra grandiflora attenuated secondary stress responses in Colossoma macropomum after 6 h transport.•Essential oil of N. grandiflora provided a sparing effect on dissolved oxygen levels in the transport bags of C. macropomum.•Spilanthesacmella extract did not imply advantages to alleviate secondary stress responses in C. macropomum post-transport.
•Modified method of lignocellulose content determination was elaborated.•Difficult lignin quantification with calibration curve usage was eliminated.•New cellulose determination method was ...proposed.•The developed procedure was checked on selected herbs.
Determination of extractives, lignin, hemicellulose, cellulose and mineral substance is a complex procedure. Lignin and hemicellulose are both alkali soluble and their mutual determination is disturbed. Moreover, the lignin occurs in two fractions - soluble and insoluble in acids, which make its determination difficult. In this paper a new, modified method of all the above components determination was described. The inaccuracies in methods reported in the literature so far were solved. There was applied not sophisticated equipment aimed at the costs reduction. The complicated, multistep lignin content determination was replaced by easier procedure of cellulose evaluation. Moreover the hemicellulose determination was improved (the error related with lignin dissolution in alkaline solution was eliminated).
The presented method was used for the nettle, sage, lemon balm and mint herbs analyses. The herbs contain a small percentage of mineral substance and are very suitable for the activated carbons preparation. It has been shown that the content of hemicellulose affects the activated carbons surface area development, whereas the lignin content has influence on the concentration of total surface functional groups. Activated carbons with the best surface properties were obtained from the herbs containing high concentrations of hemicellulose and lignin.
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