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This study explores the application of chemotaxonomic methods to trace the geographic origin of wood used in paper production. Utilizing thermal desorption gas chromatography-mass spectrometry (TD-GC-MS) and principal component analysis (PCA), distinct chemical profiles were identified in both hydrophobic and hydrophilic extracts. Residual wood extractives, that are capable of origin differentiation, were found in acetone extracts of the CITES-protected genus ramin (Gonystylus Teijsm. et Binn. spp.), petroleum ether extracts of red meranti (Rubroshorea (Meijer) P.S.Ashton et J.Heck. spp.) and n-hexane extracts of teak (Tectona grandis L.f.) pulp. The PCA results demonstrate the potential of these chemical fingerprints to serve as reliable indicators of wood provenance, which could potentially be crucial for the practical execution of the European Deforestation Regulation (EUDR) and the US Lacey Act in the paper industry. Despite the promising findings for ramin and teak, the effectiveness of the method to distinguish the origin of red meranti pulps was limited in some cases. [ABSTRACT FROM AUTHOR]

The commercial value of teak wood is associated with its heartwood, which has a naturally darker color than sapwood. To reduce this color disparity, thermal modification can be used to homogenize the color between sapwood and heartwood by minimizing color differences. This research aimed to assess the effectiveness of thermal modification in making the color of teak sapwood similar to that of heartwood. Thermal modification was carried out at 160, 180, 200, and 220 °C for 150 min. Thermal modification of teak sapwood at 180 °C ensured greater color similarity to the heartwood of a fast-growing 16-year-old plantation. The material darkened with increasing process temperature. There was a change in the content of soluble substances, and hot water extraction had greater correlations with hue angle, lightness, and yellowness. Thermal modification also reduced the number of hydroxyl groups and improved the wood's thermal stability. [ABSTRACT FROM AUTHOR]

The commercial value of teak wood is associated with its heartwood, which has a naturally darker color than sapwood. To reduce this color disparity, thermal modification can be used to homogenize the color between sapwood and heartwood by minimizing color differences. This research aimed to assess the effectiveness of thermal modification in making the color of teak sapwood similar to that of heartwood. Thermal modification was carried out at 160, 180, 200, and 220 °C for 150 min. Thermal modification of teak sapwood at 180 °C ensured greater color similarity to the heartwood of a fast-growing 16-year-old plantation. The material darkened with increasing process temperature. There was a change in the content of soluble substances, and hot water extraction had greater correlations with hue angle, lightness, and yellowness. Thermal modification also reduced the number of hydroxyl groups and improved the wood’s thermal stability.

Medicinal plants have always arised an interest because they usually have pharmacological effects, low toxicity and high safety. Herbal preparations can be used both for the prevention of certain diseases and for the treatment of chronic and slowly developing ones. At the same time, practically healthy people can also use them to improve their quality of life. The experience of using medicinal plants in traditional medicine in the North-West Caucasus (in particular, in the Republic of Adygea) contributed to their active study with the aim of introducing official scientific medicine into clinical practice.For the treatment, prevention and diagnosis of many diseases, the medications are widely used that have a sedative effect in various neurotic conditions and have a regulatory effect on the central nervous system, reducing excitatory processes, enhancing inhibitory processes or eliminating the consequences of stressful situations. In this regard, there is a need to expand the local raw material base of medicinal plants, which accumulate biologically active substances in high concentrations.The article provides data on the study of wild North Caucasian populations of medicinal plants (valerian officinalis, common hop, motherwort and peppermint), which are promising producers of biologically active compounds. The results obtained indicate the safety of the raw material, allow us to evaluate its quality and prove the promise of ongoing scientific research, which has not only theoretical but also practical significance for the purpose of creating drugs that have a sedative effect, as well as for processing without restrictions.

Political spending—funds that elite actors use to buy and sell political power—is the lifeblood of Nigerian politics. It fuels backroom deals, forges political coalitions, and is the means to incite or end violence. To date, political spending in Nigeria has largely been financed by its immense oil revenues flowing through the government. It is natural to assume that political budgets should rise and fall with oil's boom-and-bust cycles, but the reality is not so straightforward. Based on an analysis of the 2020 oil crash in Nigeria, this paper examines how traumatic decarbonization—the sudden, unplanned loss of oil revenues—did not lead to a reduction in political budgets but did force a change in how they were funded and channeled. Despite the loss in oil revenues, patronage and the "contractocracy," government contracts used to funnel rents to the elite, were protected and expanded massively in 2021 with funding from domestic and international loans. The 2020 oil crash demonstrated the resilience and rising cost of transactional politics in Nigeria, even when it came at the expense of the Nigerian people. Through this analysis, the paper further examines systemically corrupt political systems and how political actors adapt to changes in available political finance. [ABSTRACT FROM AUTHOR]

The green transition and slowdown of global fossil fuel demand present an intriguing question for the future of oil-rich developing countries where less democracy, unstable and inequitable economics, and conflict have long been prevalent. Sudan offers an ex-ante look at the consequences of this transition to a post-oil world. In 2011, Sudan lost three-quarters of its oil resources after South Sudan's separation. This article explores the impact of decarbonization on Sudan's political economy and the role of natural resources in shaping its elite politics and foreign relations. It argues that in the short term and mid-term, the Sudanese state was able to weather the loss of most of its oil, with incumbent political elites demonstrating staying power beyond the expiry date of high oil rents. In the long term, however, rather than a diversified economy and democratic alternative emerging, both Sudan's longstanding predatory political economy and its external exploitative links endured the decline of oil. The rising economic importance of gold, and its political ecology as a dispersed and lootable resource, coupled with opportunities for regional extraversion facilitated the violent rise of new political elites and shaped a shift in Sudan's main foreign economic partners from China to the Gulf states. [ABSTRACT FROM AUTHOR]

Iraq is a compelling example of a state highly dependent on a singular source of rent, namely oil revenue. Since 2003, Iraq has also been characterized by a fractured, rivalrous elite without central control over organized violence. This formula represents a "rentier political marketplace" in which state funds for salaries and contracts are the essential lubricant of the political system. During 2014–2021, successive shocks to national oil revenues represented a partial and temporary, but traumatic, decarbonization of Iraq's government and political finance. In turn, this triggered a series of governance and political reconfigurations including a nominal decentralization process and fracturing of sectarian power, followed by a nationwide civic movement demanding transformational change. This paper traces these changes and the abrupt return to business as usual when oil prices rebounded. In doing so, the paper further investigates the nexus between oil and democracy in Iraq and addresses the unanswered question of how Iraq can decarbonize and democratize in the future. [ABSTRACT FROM AUTHOR]

A global energy transition from carbon-based fuels to renewable energy will have major political and economic ramifications around the world, especially for fragile fossil fuel-producing states, but these impacts are not yet well understood let alone prepared for. In many fragile fossil fuel-producing countries, an energy transition is not simply a transformation of the energy sector, but also a fundamental challenge to the political economy of the state and the way politics is practiced. This challenge is likely to be destabilizing, politically fraught, and perhaps even violent, yet the "new climate economy" literature does not fully consider the implications of what the loss of these revenues will mean, and the solutions offered do not speak to the realities of how these states operate. This article examines the different risks and opportunities of an energy transition for these states and outlines a research agenda to better understand and prepare for these outcomes. [ABSTRACT FROM AUTHOR]

The article, titled "Progress, politics and the place of elite black African women in Kenya’s extractive sector," explores the experiences of elite black African women working in Kenya's extractive sector. The dissertation challenges mainstream feminist theories and methods, arguing that they fail to effectively engage with the experiences of black African women in this traditionally masculine sector. The study adopts African feminisms as an alternative lens for understanding the intersection of race, gender, and elitism in the extractive sector. It also examines the role of place-making and the construction of the ideal worker body in shaping the experiences of black African women in the sector. [Extracted from the article]

Wood extractives have proven strong anti-oxidative properties which may be used to mitigate surface deterioration caused by photolytic effects and free radical formations. An interesting challenge regarding wood extractives is understanding how they behave in terms of treating natural wood surfaces to reduce anti-oxidative processes that arise from exposure to the main environmental factors. In this study, the possible efficacy of chestnut (Castanea sativa Mill.) extractives derived from native (CH) and thermally modified wood (TMT CH), as a means of protecting against UV exposure in poplar (Populus spp.) and spruce (Picea abies Karst.) wood, was evaluated. Chestnut wood was first thermally modified at 180 °C for 3 h, and the extractives were obtained by the accelerated solvent extraction technique (ASE) and subsequently used to treat wood surfaces. Samples were immersed in extractive solutions and exposed to artificial UV-weathering exposure, then contact angle and colour stability were monitored during the process. An FTIR analysis of the photo-degradation process of poplar and spruce surfaces was also executed. Extractives of TMT chestnut changed the total colour variation in both poplar and spruce wood. A much darker colour compared to the extractives of native wood was observed and an increase in ∆E* from 9.75 to 30.76 and 6.24 to 22.97 in poplar and spruce was calculated. The stability of the colour depended both on the surface wood and the type of extractive. The initial contact angle remained almost unchanged in the poplar wood surface and only slightly increased in spruce regardless of whether they were treated with extractives from native or TMT chestnut wood. A strong reduction in contact angle after the accelerated UV exposure test was observed, especially in spruce treated with CH extractives. FTIR analysis confirmed the lower levels of chemical degradation of surfaces observed by colorimetry, where TMT CH extractives formed more stable chemical bonds than native extractives. The comparative analysis in this study clarified the complex relationships between the effects of high-temperature modification of wood and the potential protective role of TMT extractives on some wood surfaces. [ABSTRACT FROM AUTHOR]

This study aimed to determine the influence of increased temperature on the mass loss, chemical composition, and colour of pine wood because of the lack of such information. The colour was measured on samples of wood, extracted sawdust, holocellulose, and lignin isolated from the extracted sawdust of pine heartwood and sapwood. A wood sample labelled 20 °C was considered as wood with the original composition. Subsequently, we verified the measured values with the proposed mixing colour model. Pine heartwood and sapwood samples were thermally treated at temperatures of 100, 150, 200, 220, 240, and 260 °C for 1, 3, and 5 h. It was found that sapwood degraded faster than heartwood. The thermal treatment of wood increases lignin content and decreases holocellulose content, especially at 260 °C. The maximum extractive content of 3.60% was at 1 h and a temperature of 260 °C for both parts of the wood. Lightness values decreased with increasing temperature and time of treatment. The coordinate a* of heartwood showed a positive slope until one hour of treatment duration and a temperature of 240 °C. Then, it decreased for the subsequent duration of treatment. The same course was shown for the coordinate b* of sapwood at a temperature of 200 °C. The proposed model of mixing colours proved that changes in both parts of a wood-extracted substance, holocellulose, and lignin content, were responsible for the changing colour of extracted wood. [ABSTRACT FROM AUTHOR]

Wood durability is vital for its long-term performance in outdoor applications, influenced by various factors. This study investigates the impact of leaching biologically active substances due to weathering on wood durability. The research covers multiple wood species and treated wood subjected to natural and accelerated weathering. Chemical analysis includes extraction, spectrophotometry (UV-Vis), chromatography (HPLC), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray fluorescence spectroscopy (XRF). Additionally, fungal and wetting ability tests were conducted. Results indicate significant extractive leaching during weathering. However, the part of the extractives with the highest biological activity, i.e. the phenolic compounds, were slightly less susceptible to leaching than other extractives. While FTIR analysis suggests minimal degradation of other wood compounds, accelerated weathering induced notable extractive loss. Weathering adversely affected inherent durability and wetting ability, leading to reduced relative resistance dose according to the Meyer-Veltrup model. Black locust exhibited the least reduction, while pine heartwood showed the highest decrease in resistance dose. Paste tests revealed fungicidal components' contribution to wood durability, indicating its multifaceted nature. This comprehensive study sheds light on the intricate dynamics between weathering, extractive leaching, and wood durability, offering insights crucial for optimizing wood treatment and preservation methods in outdoor environments.

Studies on wood durability have highlighted the use of new environmentally friendly substances. In this sense, research carried out with Amazonian forest species is extremely important for the discovery of new bioactive substances from durable wood and its residues. The aim of this study was to evaluate the antitermitic and antifungal potential of extracts obtained from industrial processing residues of wood species from Central Amazonia, Brazil. The sawdust of seven Amazonian wood species were collected to obtain extracts and quantify the extractive content. The extracts produced were tested for inhibition of fungal growth of Rhodonia placenta and Trametes versicolor and impregnated in low natural durability wood known as Simarouba amara (marupa) to verify the effect on wood natural durability against Nasutitermes sp. termites and Gloeophyllum trabeum fungus. Simarouba amara (marupa) wood was easily impregnated and showed satisfactory retention values. The species Buchenavia sp., Dinizia excelsa (red angelim), Hymenolobium flavum (angelim pedra) and Manilkara elata (maçaranduba) exhibited high contents of secondary metabolites. It was observed that the extracts of Roupala montana (louro faia) and Hymenolobium flavum (angelim pedra) exhibited the best performance in inhibiting fungal growth. In the accelerated decay test, marupa wood impregnated with Buchenavia sp. (tanimbuca) extract showed the lowest weight loss after exposure to the fungus Gloeophyllum trabeum. In the termite choice feeding test, wood impregnated with Dinizia excelsa (red angelim) and Buchenavia sp. (tanimbuca) extracts were most consumed and the extracts of Roupala montana (louro faia), Cordia sp., Hymenolobium flavum (angelim pedra) and Manilkara elata (maçaranduba) provided greater inhibition of termite attack. The combination of extracts must be tested in future studies to verify the synergistic effect, in addition to the chemical analyses of the selected extracts.

Abstract Termites of the genus Nasutitermes sp. (Blattodea: Termitidae), which feed on cellulose, may cause wood to become brittle and fragile. This study aimed to evaluate the natural resistance of three native wood species: Magonia pubescens (Sapindaceae), Dalbergia nigra and Machaerium amplum (Fabaceae) to attack by Nasutitermes sp. termites and to investigate the relationship between resistance, extractive content, and oven-dry density. Samples of each wood species were subjected to a forced feeding process with Nasutitermes sp. termites for 30 days. Following the exposure, the oven-dry density, extractive content, percentage of wood loss, and termite mortality were determined for each sample. Dalbergia nigra exhibited resistance to termite attack and had the highest extractive content at 13.14%. Conversely, M. amplum had the highest wood loss at 5.37% and the lowest extractive content at 1.94%. Both species showed a negative correlation between wood loss and extractive content, but no correlation with wood density. Magonia pubescens had the highest density at 0.90 g/cm3. Macherium amplum and M. pubescens caused 100% termite mortality, while D. nigra caused 40% mortality.

Cost-effective, non-destructive means of estimating wood properties of eucalypts grown in Guangxi, China, were evaluated using near infrared (NIR) spectroscopy and resistance drilling. For this evaluation, wood samples for NIR analysis and resistance drill measurements were collected from 581 trees, representing eight plantation Eucalyptus taxa across five sites. The near infra-red (NIR) spectra collected from the 581 wood samples were analysed using existing calibrations for kraft pulp yield, cellulose content, hot water extractives and Klason lignin. These spectra and calibrations were effective in predicting over 60% of the variance in total carbohydrates and over 80% of the extractives and lignin values from independent laboratory analysis of a subset of 100 samples. Resistance drilling combined with software developed for processing the drill data proved to be a quick, low cost and effective means of quantifying wood density (as amplitude of the drill torque), stem diameter and bark thickness. [ABSTRACT FROM AUTHOR]

Cordia elaeagnoides A. DC. is an endemic species of Mexico valued for its timber. Renowned for its durability, resistance, and versatile applications in medicine, this tree holds significant commercial importance. Tetrahydrofuran (THF) extract from the heartwood of C. elaeagnoides was studied. Through chromatographic column purification, the compound 8-(2,5-Dihydroxyphenyl)-2,6-dimethylocta-2,6-dienal, also known as alliodorin, was successfully isolated. Identification of alliodorin was confirmed through comprehensive analysis utilizing NMR, IR, and mass spectrometry techniques. Inhibition tests were conducted using both the THF extract and alliodorin against the rotting fungus Trametes versicolor (L.) Lloyd, employing the agar well diffusion assay. Remarkably, alliodorin exhibited 100% inhibition with a median lethal concentration of 0.079 mg/mL and a total lethal concentration of 0.127 mg/mL, in comparison to the commercial fungicide benomyl, which requires a concentration of 1 mg/mL. In silico analysis through molecular docking on the laccase enzyme was proposed in order to explain the inhibitory activity against the fungus T. versicolor, as this enzyme is one of the main sources of nutrients and development for the fungus. Based on these findings, we deduced that alliodorin holds promise as a potent antifungal agent, potentially applicable in a wide array of technological and environmentally friendly initiatives. [ABSTRACT FROM AUTHOR]

Amazon offers several lignocellulosic biomasses with unknown technological properties contrasting with a growing demand for activated charcoal for water decontamination. Thus, this work investigated the chemical features of the murumuru (MS) and patauá (PS) palm seeds and their thermal behavior during pyrolysis up to 600 °C to verify their suitability for the future production of chemically activated carbon. The biomasses showed similar H(%)/C(%) ratios (≈ 0.13) and lignin contents (≈ 24%), both features closely related to increased activated carbon yield. Regarding the possibility of providing highly porous adsorbents, PS depicted more cellulose and hemicelluloses favorably. On the other hand, MS showed an outstandingly high level of total extractives (31%) compared to PS and most lignocellulosic biomasses of literature. Ultimately, the proximate analysis revealed that PS's volatile material (%)/fixed carbon (%) was 2.4, much lower than MS's one of 3.8. As a drawback for pyrolysis yield, both palm wastes showed ash levels (≈2%) above many other previously studied lignocellulosic biomasses. However, near-infrared spectroscopy analysis revealed some oxygenized chemical groups able to raise the acidity of derived activated carbons, promising to adsorb cations. Murumuru (23.7%) showed a lower pyrolysis yield than patauá (30.7%) at 600 °C. Temperatures below 400 °C are more suitable for the pyrolysis of murumuru seeds, while patauá seeds stand higher temperatures without compromising the charcoal yield. Therefore, high extractive content surpassed other chemical traits in influencing pyrolysis yield. Statement of novelty This thermo-chemical and thermal characterization study makes it possible to trace the potential of understudied palm seeds, such as murumuru and patauá, for producing activated carbon. [ABSTRACT FROM AUTHOR]

Key message Wood_db-chemistry gathers information on oak, beech and Douglas fir extractives studied between 1950 and 2020. The data can be used by researchers, stakeholders in the forest-wood sector and the chemical industry to make the most of the extractives and their bioactive properties through knowledge of their diversity in the forest resource. Dataset access is at https://doi.org/10.57745/QZYPUA . Associated metadata are available at https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/4f8c07d2-c0f6-4958-8f74-936054a9870a .

The valorisation of lignocellulosic resources, such as oat husks, as components in cementitious composites presents challenges regarding their compatibility with the matrix due to the solubilisation of their surface components and products from alterations induced by the alkaline environment of lime-based matrices. These negatively affect the matrix. This study aims to fill the knowledge gap regarding the compatibility and effects of the extractives found in oat husks with the cement matrix. It intends to characterise oat husks’ structural composition, evaluate the extractive removal efficiency, assess their influence on cement matrix hydration using thermogravimetric techniques, and analyse mechanical strength development between 3 and 28 days. The study concludes that hot water is more efficient for extractive removal, and the immersion duration is more relevant than the number of washing cycles. Furthermore, it confirms that husks’ extractives inhibit cement matrix hydration products and mechanical strength development, especially in the presence of degradation products. These findings are essential for determining more efficient approaches to enhance compatibility between oat husks and cementitious matrices.

Resin production in wood tissues is a regular feature of pine wood species, including southern pine. High resin contents of southern pine wood may increase wood resistance against decay fungi. The current study investigated the effect of resin contents in southern pine wood on decay resistance by exposing non-extracted heartwood, mixed wood (sapwood + heartwood), and sapwood blocks with varying resin content to brown rot, Fomitopsis ostreiformis in a laboratory decay test. Matching blocks of each wood type were successively extracted in a Soxhlet using three solvents to determine resin content and were exposed to decay fungus in parallel. Results showed that mass losses in non-extracted heartwood and mixed wood depended on resin content levels, and very shallow or no mass losses were observed in blocks containing more than 31 % resin content. Sapwood experienced high mass losses, but the presence of resinous extractives significantly increased the decay resistance. All solvent-extracted blocks experienced high mass loss (53–55 %). Scanning electron microscopy showed that penetration of brown rot hyphae and cell damage depended on the resin contents of blocks. Most of the identified compounds through GC-MS belonged to oleoresins, among which monoterpene hydrocarbons, oxygenated monoterpenoids, and sesquiterpenes were more abundant in heartwood than sapwood. [ABSTRACT FROM AUTHOR]

The valorisation of lignocellulosic resources, such as oat husks, as components in cementitious composites presents challenges regarding their compatibility with the matrix due to the solubilisation of their surface components and products from alterations induced by the alkaline environment of lime-based matrices. These negatively affect the matrix. This study aims to fill the knowledge gap regarding the compatibility and effects of the extractives found in oat husks with the cement matrix. It intends to characterise oat husks' structural composition, evaluate the extractive removal efficiency, assess their influence on cement matrix hydration using thermogravimetric techniques, and analyse mechanical strength development between 3 and 28 days. The study concludes that hot water is more efficient for extractive removal, and the immersion duration is more relevant than the number of washing cycles. Furthermore, it confirms that husks' extractives inhibit cement matrix hydration products and mechanical strength development, especially in the presence of degradation products. These findings are essential for determining more efficient approaches to enhance compatibility between oat husks and cementitious matrices. [ABSTRACT FROM AUTHOR]

Background and Objectives: Plant extractives show unique properties. They impart colors and change the color of wood and generates attractive appearance. Since early days, societies have been utilizing plant extractives in industrial, medical and even as fungicides and biocides. In early times this application was based on the professional experiences, but as the sciences were advanced, then the technical and experimental identification and utilization was employed. In general, people look at walnut tree wood and fruit as its economic values. However, scientific research has proved the values of walnut tree extractives. In this study the chemical composition of walnut tree extractives and its variation in two periods of spring and summer as well as the impact of the drying on quantity and quality of the extractive components are investigated. Methodology: Walnut tree leaves from a selected location of an old walnut tree (100 years old) in mountain region of Karaj were collected in spring and summer. One part of the samples was air dried and another portion was used at green moisture condition. Totally four samples were obtained. Ethanol-acetone extraction was according to Tappi T204-05 procedure. The extractive was analyzed using GC-MASS spectroscopy and the chemical components in the extractives were identified and tabulated. Results: The results revealed that the dried leaves contain fewer chemical compounds compared to green samples which can be an indication that some of the compounds in green sample are volatile and vaporize upon drying. Furthermore, the extractives chemical composition and content varies between spring and summer samples. The major chemical compounds identified were 2-methylneptaline, tri-decan, tetradecan, 2,3-dimethyl naptaline and methylcyclobenzen. Conclusion: The results indicated the seasonal variation of walnut tree extractives. These is also considerable variation in wet and dry samples which can be attributed to the presence of volatile compounds. The odor of walnut leaves is the consequence of the presence of such volatile compounds. The absence of some of the compounds in summer samples indicate the seasonal changes of the extractives. [ABSTRACT FROM AUTHOR]

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Simple Summary: Extractives, the non-structural component of woody biomass, are frequently targeted for their biocidal potential due to their evolutionary success in deterring pests in both standing trees and downed woody debris. Effective extractive utilization also offers an alternative product stream, where extractives are removed from the woody biomass that can further be used as feedstock for downstream processes (i.e., pulping, nanocellulose production, and biochar) once the extractives are removed. This review aims to provide details on prior studies using wood extractives as wood protectants, highlight the limitations to this approach, and discuss the research opportunities. Naturally durable wood pre-dates preservative-treated wood and has been demonstrated to offer a suitable service life for certain applications where preservative-treated wood is not feasible. Heartwood extractives have been demonstrated to impart bio-deteriorative resistance to naturally durable wood species. These extractives are typically found in the heartwood of living trees and are produced either by the death of parenchyma cells or as the result of external stimuli. The mechanisms of natural durability are not well understood, as heartwood extractives can be extremely variable in their distribution, composition, and efficacy in both living and harvested trees. The underlying complexity of heartwood extractives has hindered their standardization in residential building codes for use as wood preservatives. The use of naturally durable lumber is not always feasible, as woods with exceptionally durable heartwood do not typically yield lumber with acceptable machining properties. A potential approach to overcome the inherent difficulty in establishing guidelines for the appropriate use of naturally durable wood is to focus solely on the extractives as a source of bioactive protectants based on the strategies used on living and dead wood to repel the agents of biodeterioration. This critical review summarizes the relevant literature on naturally durable woods, their extractives, and their potential use as bio-inspired wood protectants. An additional discussion will be aimed at underscoring the past difficulties in adopting this approach and how to overcome the future hurdles. [ABSTRACT FROM AUTHOR]

Ghana’s forest is fast depleting as a result of over-dependency on the traditionally known timber species and high demand for wood products for structural works. This study seeks to determine the chemical properties and basic density of Terminalia catappa wood and its potential for structural application. Three mature trees of Terminalia catappa were acquired based on the diameter at the breast height (dbh) greater than 40 cm. In this study 160 samples of wood were used for the chemical properties and density tests. Chemical analyses were performed by using the TAPPI standards. The study revealed that there were higher cellulose and hemicellulose contents in the sapwood than in heartwood, and in the branchwood than in stemwood. Lignin and extractives content were higher in the heartwood than in sapwood, and in the stemwood than in branchwood. The basic density of the sapwood ranged from 473 to 649 kg/m³ and in the heartwood from 444 to 579 kg/m³ being the highest in the base portion and the lowest in the branches. The difference in wood density, which is greater in the base area than the branches, emphasizes how crucial it is to take wood quality into account for the best possible use across various tree portions. The study also clarifies the wood's suitability for structural and non-structural uses. These findings have the potential to influence sustainable forest management strategies and encourage the use of alternative timber to supplement the resource base.

The content of phenolic compounds in the fruits of various plant species of the family Ericaceae, collected on the territory of the Republic of Sakha (Yakutia) during the fruiting period in July–August, was studied. The study confirms that plants growing in permafrost conditions accumulate large amounts of phenolic compounds. As a result of phytochemical analysis, it was found that the most valuable plant raw material in terms of content of phenolic compounds is Vaccinium uliginosum.

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 objective of this research was to establish comparatively some relevant features of Turkey oak and sessile oak wood, in order to better understand the drying behavior of these species. The analyzed samples were obtained from freshly harvested trees of the same age, originating from the Southern Sub-Carpathians. The microscopic analysis revealed that Turkey oak has larger earlywood pores than sessile oak. In heartwood, they are partly filled with tyloses for both species. The macroscopic analysis showed that Turkey oak wood has a much lower proportion of heartwood (only 50%) compared to sessile oak (90%). The comparative FTIR analysis of the two species showed similar qualitative chemical composition, but also some differences between sapwood and heartwood regarding the relative proportion of the main constituents, and very likely in the structure of lignin. High amounts of extractives were found in Turkey oak sapwood (5.34% in cold water, 7.77% in hot water, and 21.60% in NaOH 1%), close to the values obtained in sessile oak heartwood. The research also revealed that the Turkey oak sapwood and heartwood have statistically similar values of oven-dry density, shrinkage coefficient, fiber saturation point, while in sessile oak, the values are clearly higher in the heartwood.

Sustainable materials are becoming increasingly important due to environmental concerns and the energy crisis. Non-wood resources such as bamboo are being explored as alternatives to wood-based materials to reduce deforestation. However, the chemical properties of these resources determine their usability. This study analyzed the chemical composition and solubility of Bambusa bambos (L.) Voss, a type of bamboo. The effects of age and height position (top, middle, and bottom) on the chemical composition and solubility were also considered. The study followed the standards of TAPPI (Technical Association of the Pulp and Paper Industry) to analyze holocellulose, lignin, and extractive content, and water (hot and cold) and caustic soda (1% NaOH) solubility. The results showed that the chemical composition, i.e., holocellulose, lignin, and extractive, increased while solubility, i.e., cold water, hot water, and NaOH, decreased with the ageing of B. bambos. The average holocellulose, lignin, and extractive contents of three-year-old B. bambos were 70.49%, 27.55%, and 4.54%, respectively. These values were within the range of previous studies, indicating that B. bambos has potential applications in various purposes.

Understanding the durability of emerging plantation hardwood resources is important for optimising their production and use. This study compared timber density, extractives content and decay resistance in 12–13-year-old plantation and native forest regrowth Gympie messmate (Eucalyptus cloeziana) trees. Density increased from pith to bark for both plantation and native forest trees. Inner heartwood density of the plantation timber was significantly lower than that of the native forest regrowth timber. While the total extractives content of the outer heartwood was comparable in the plantation and native forest regrowth trees, the inner heartwood of the latter contained significantly greater extractives levels. Laboratory decay tests showed that all heartwood zones of plantation and native forest regrowth Gympie messmate were resistant to decay by the white rot Pycnoporus coccineus. The inner heartwood of the plantation timber was, however, susceptible to decay by the brown rot Fomitopsis ostreiformis. The results illustrate the potential variations in wood quality parameters to be considered when moving from native forest to plantation resources that are harvested at a younger age and managed for more rapid wood production. [ABSTRACT FROM AUTHOR]

The European Deforestation Regulation 2023/1115 (EUDR) prohibits trading of wood and wood products obtained from illegal logging on the EU market. While the identification of solid wood via anatomy, chemistry and genetics has already been established, there is a lack of identification methods for pulp and paper that complement anatomy. This publication presents a newly developed chemotaxonomic method for identifying mixed tropical hardwood (MTH) species in pulp and paper products based on their extractives analyzed with thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). The measured data was processed and compared to identify marker substances and was then merged into a fingerprint database for identifying MTH species in paper of unknown composition. As database references, fully bleached kraft pulps were produced from 38 anatomically identified wood samples and then cryo-ball milled and extracted successively with n-hexane and acetone. The results show that the remaining wood extractives generated from bleached pulps are specific enough to find chemical relevant marker substances to detect MTH species. As chemical composition and anatomy are independent characteristics of wood, this paper makes a completely independent method available, which potentially improves the screening for Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) protected species. [ABSTRACT FROM AUTHOR]

Maritime pine, scientifically known as Pinus pinaster, holds a vital role in Iberian Peninsula forests, primarily as a source of wood for panels, paper, and cellulose production. Recently, there has been a growing interest in utilising agroforestry by-products to yield valuable chemicals for applications in various sectors, including the food, pharmaceutical, and bioenergy industries. This study aimed to assess the value of the primary by-product of Pinus pinaster from the Minho region of northwestern Portugal, i.e., the bark. The research extensively examined the bark's chemical and thermal characteristics, including ash content, extractives, lignin, cellulose, hemicellulose, fatty acids, and mineral composition. Additionally, various analytical techniques like FTIR, SEM, DSC, DTG, and XRD were used to observe chemical structure differences. The results reveal that the Pinus pinaster bark primarily consists of lignin (51.15%) and holocellulose (46.09%), with extractives mainly soluble in toluene–ethanol, followed by water, and a small amount of them are soluble in ethanol. The bark contained around 0.44% ash, and heavy metals such as Cd and Pb were not found. During degradation, Pinus pinaster experienced a 10% mass loss at 140 °C. In terms of crystallinity, holocellulose and cellulose showed similar percentages at approximately 25.5%, while α-cellulose displayed the highest crystallinity index at 41%. [ABSTRACT FROM AUTHOR]

This work examines the effect of thermal modification temperature (180, 200, and 220 °C) in comparison with reference (untreated) samples on selected optical properties of six tropical wood species—Sp. cedar (Cedrala odorata), iroko (Chlorophora excelsa), merbau (Intsia spp.), meranti (Shorea spp.), padouk (Pterocarpus soyauxii), and teak (Tectona grandis). The main goal is to expand the existing knowledge in the field of wood thermal modification by understanding the related degradation mechanisms associated with the formation of chromophoric structures and, above all, to focus on the change in the content of extractive substances. For solid wood, the CIELAB color space parameters (L*, a*, b*, and ΔE*), yellowness (Y), ISO brightness, and UV-Vis diffuse reflectance spectra were obtained. Subsequently, these wood samples were extracted into three individual solvents (acetone, ethanol, and ethanol-toluene). The yields of the extracted compounds, their absorption spectra, and again L*, a*, b*, ΔE*, and Yi parameters were determined. With increasing temperatures, the samples lose brightness and darken, while their total color difference grows (except merbau). The highest yield of extractives (mainly phenolic compounds, glycosides, and dyes) from thermally modified samples was usually obtained using ethanol. New types of extractives (e.g., 2-furaldehyde, lactones, formic acid, some monomer derivatives of phenols, etc.) are already created around a temperature of 180 °C and may undergo condensation reactions at higher temperatures. For padouk, merbau, teak, and partially iroko modified at temperatures of 200 and 220 °C, there was a detected similarity in the intensities of their UV-Vis DR spectra at the wavelength regions corresponding to phenolic aldehydes, unsaturated ketones, quinones, stilbenes, and other conjugated carbonyl structures. Overall, a statistical assessment using PCA sorted the samples into five clusters. Cluster 3 consists of almost all samples modified at 200 and 220 °C, and in the other four, the reference and thermally modified samples at 180 °C were distributed. The yellowness of wood (Y) has a very high dependence (r = 0.972) on its brightness (L*) and the yellowness index of the extractives in acetone Yi(Ac), whose relationship was described by the equation Y = −0.0951 × Y(Ac) + 23.3485. [ABSTRACT FROM AUTHOR]

Natural durability is one of the most rated features in wood end-use applications. In fact, several precious native tropical wood species produce timber of high natural durability, which is also related to long service life even for the highest hazard classes. However, selective logging is driving the existing volume of this group of species to near extinction. The remainder of the alternative species produces perishable timbers, which require synthetic chemical protection to prolong their service life but with detrimental effects on humans and the environment. Therefore, transferable durability has emerged as an alternative to gradually substitute traditional wood preservatives. From this approach, extractives from naturally durable wood species are removed and transferred to the non-durable wood species as an alternative environmental-friendly option for wood protection. Indeed, extractives from durable wood species have proven to have a deterrent effect on fungi, bacteria and termites and could be used to protect perishable wood species. Thus, this review aims to assess the prospects of developing environmentally friendly wood preservatives based on extractives sourced from highly natural, durable wood species to treat and add value to the group of perishable timbers. A step-wise analysis offers insights and challenges on (i) potential sources of extractives; (ii) effective extraction methods; (iii) extractive-based preservative formulation; and (iv) effective treatment methods for better preservative fixation for better wood protection. Accounts about the way forward for the development of extractive-based wood preservatives are also presented. [ABSTRACT FROM AUTHOR]

Plasma‐enhanced chemical vapor deposition is a highly promising tool for coating deposition due to its versatility, tunability, low chemical consumption, and cost‐effectiveness, with an increasing scope of deposition methods at both low and atmospheric pressure. Adhering to green chemistry principles, biobased precursors have recently shifted into the focus of research interests. This review gives an overview of the main biogenic substance classes that have been used for the deposition of plasma polymer coatings, including natural oils, terpenes, enzymes, and lactic acid‐based precursors. The common feature of these precursors is not only their biogenic origin, but additionally the manifold properties of the resulting plasma‐deposited thin films, ranging from antimicrobial properties to tunable surface‐wetting characteristics, electrical conductivity, or biodegradability. This combination of unique features makes plasma‐derived polymers based on natural precursors immensely attractive for manifold applications. [ABSTRACT FROM AUTHOR]

Secondary metabolites were isolated using chromatographic techniques after being extracted sequentially from the roots of Artemisia afra using organic solvents such as ethanol, ethyl acetate, dichloromethane, and n-hexane. The isolated compounds were evaluated for anti-fungal, anti-bacterial, and cytotoxicity activities. Spectroscopic techniques, including Nuclear Magnetic Resonance (NMR), Fourier transform infrared (FTIR), and liquid chromatography–mass spectrometry (LC-MS), were used to elucidate the structures of the isolated compounds. The phytochemical investigation of A. afra led to the isolation of eight (A–H) compounds which were identified as 3β-taraxerol (A), 3β-taraxerol acetate (B), dodecyl-p-coumarate (C), ferulic acid (D), scopoletin (E), sitosterol-3-O-β-D-glucopyranoside (F), 3,5-di-O-feruloylquinic acid (G) and Isofraxidin-7-O-β-D-glucopyranoside (H) based on spectroscopic data. Compounds A, B, C, F, G, and H are known but were isolated for the first time from the roots of A. afra. The isolated compounds and extracts from A. afra exhibited good anti-fungal and anti-bacterial activity with dichloromethane and ethyl acetate crude extracts (0.078 mg/mL) and compound E (62.5 µg/mL) showed good activities against Escherichia coli. Compounds C and F also showed good activity against Enterococcus faecalis with minimum inhibitory concentration (MIC) values of 62.5 and 31.25 µg/mL, respectively. Extracts and compounds (A–H) exhibited anti-fungal and anti-bacterial properties and showed no toxicity when tested on Vero monkey kidney (Vero) cells. [ABSTRACT FROM AUTHOR]

Effects of thermal modification were determined relative to chemical parameters of Pinus roxburghii. Thermal modification of wood was carried out at 80, 120, 160, and 200 °C for 2, 4, and 6 h. The chemical properties were different for different temperatures and different heating time. All parameters were similar except for cold water soluble extractives. Among the chemical properties studied, the maximum mean value of cold water extractives (8.20%), hot water soluble extractives (12.7%), holocellulose content (71.8%), and ash content (1.46%) were recorded at 120 °C, whereas the maximum mean values of alcohol benzene soluble extractives (13.9%) and lignin content (33.7%) were observed at 200 °C. The minimum mean value of cold water soluble extractives (5.82%), hot water soluble extractives (9.27%), holocellulose content (65.8%), and ash content (1.03%) were found to be at 200 °C, while the highest value of alcohol benzene soluble extractives 12.2% (control) and lignin content (28.0%) were found to be at 80 °C.

Cordia elaeagnoides A. DC. is an endemic species of Mexico valued for its timber. Renowned for its durability, resistance, and versatile applications in medicine, this tree holds significant commercial importance. Tetrahydrofuran (THF) extract from the heartwood of C. elaeagnoides was studied. Through chromatographic column purification, the compound 8-(2,5-Dihydroxyphenyl)-2,6-dimethylocta-2,6-dienal, also known as alliodorin, was successfully isolated. Identification of alliodorin was confirmed through comprehensive analysis utilizing NMR, IR, and mass spectrometry techniques. Inhibition tests were conducted using both the THF extract and alliodorin against the rotting fungus Trametes versicolor (L.) Lloyd, employing the agar well diffusion assay. Remarkably, alliodorin exhibited 100% inhibition with a median lethal concentration of 0.079 mg/mL and a total lethal concentration of 0.127 mg/mL, in comparison to the commercial fungicide benomyl, which requires a concentration of 1 mg/mL. In silico analysis through molecular docking on the laccase enzyme was proposed in order to explain the inhibitory activity against the fungus T. versicolor, as this enzyme is one of the main sources of nutrients and development for the fungus. Based on these findings, we deduced that alliodorin holds promise as a potent antifungal agent, potentially applicable in a wide array of technological and environmentally friendly initiatives.