Molecular self-organization of wood lignin-carbohydrate matrix.

MAIN CONCLUSION: The analysis of the state of research on the chemical composition, functional nature and structure of the main components of the lignin-carbohydrate matrix allows considering the wood substance as a thermodynamically self-organizing nanobiocomposite system. Features of biosynthesis of the wood matrix main biopolymers, the formation of their functional nature and structure determine the complex hierarchical organization of cell walls. The supramolecular level of biosynthesis considers the interaction of cell wall components. On the one hand, these are questions of dynamics of cell walls synthesis and processes of self-organization that control the formation of chaotic objects of biological origin; on the other hand, it is the question of thermodynamic compatibility of plant tissue components. Various models of structural organization are currently being considered, focusing on various features (biological, chemical, structural) of wood substance. At the same time, the lignin-carbohydrate matrix is a three-component system of natural polymers: lignin-hemicelluloses-cellulose, the state of which is described by specific values of thermodynamic parameters that characterize the degree of its stability. The new approach proposed in this paper allows considering the plant lignin-carbohydrate matrix from the standpoint of physical chemistry of polymer as quasi-equilibrium, thermodynamically limited ordered system of biopolymers. Thus, the biochemical processes of synthesis and self-organization lead to the formation of a complex multicomponent system of wood substance, considered as a nanobiocomposite. This determines the need to study the applicability of the fundamental cycle "structure-functional nature-properties" from the standpoint of physical chemistry of biopolymers both for the investigation of plant objects and for the development of modern technologies for complex processing based on the principles of "green chemistry".

Selective extraction of terpenoid compounds of Juniperus communis L. wood in the medium of a binary solvent (supercritical CO2 with modifier).

INTRODUCTION: Juniperus communis L. is a wood species used in folk medicine since it has a variety of wood extractives with a wide range of pharmacological properties. The morphological features of juniper wood structure leads to the necessity for the application of activation, which facilitates extraction of wood extractives. The methods of thermochemical activation can be used to improve the existing schemes of extraction. OBJECTIVE: This work aims to develop methods that increase the selectivity and efficiency of the extraction of pharmacological biologically active substances from the Juniperus communis wood. METHODOLOGY: The thermochemical activation of the juniper wood matrix involves treatment by steam explosion and the use of supercritical fluid extraction methods. Gas chromatography mass spectrometry analysis was used to identify the components of the obtained extracts. RESULTS: It is shown that the supercritical fluid extraction by a binary solvent facilitates the extraction of the maximum amount of sesquiterpene and diterpene alcohols, terpene oxides and ketones. Extracts obtained during the two-stage process with the traditional extraction in a Soxhlet apparatus at the first stage and the supercritical fluid extraction at the second, contain squalene as the main component. The two-stage treatment with steam explosion at the first stage facilitates the extraction of the maximum amount of diterpene alcohols having the widest range of biological activity. CONCLUSION: The research demonstrates the prospects of application of the methods of thermochemical activation of plant raw materials for the extraction of the wide spectrum of terpene components.

GWAS reveals genetic basis of a predisposition to severe COVID-19 through in silico modeling of the FYCO1 protein.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, is heavily reliant on its natural ability to "hack" the host's genetic and biological pathways. The genetic susceptibility of the host is a key factor underlying the severity of the disease. Polygenic risk scores are essential for risk assessment, risk stratification, and the prevention of adverse outcomes. In this study, we aimed to assess and analyze the genetic predisposition to severe COVID-19 in a large representative sample of the Russian population as well as to build a reliable but simple polygenic risk score model with a lower margin of error. Another important goal was to learn more about the pathogenesis of severe COVID-19. We examined the tertiary structure of the FYCO1 protein, the only gene with mutations in its coding region and discovered changes in the coiled-coil domain. Our findings suggest that FYCO1 may accelerate viral intracellular replication and excessive exocytosis and may contribute to an increased risk of severe COVID-19. We found significant associations between COVID-19 and LZTFL1, FYCO1, XCR1, CCR9, TMLHE-AS1, and SCYL2 at 3p21.31. Our findings further demonstrate the polymorphic nature of the severe COVID-19 phenotype.