Study of the relationship between geometric isomerism and biologically active properties of compounds

The results of the research in the field of studying the relationship of the geometric structure of organic compounds with their biological activity are presented. It has been shown that the stereospecific structure of organic and inorganic molecules can have a direct effect on the biologically active properties of substances. Among the known types of stereoisomerism (geometric and optical), this work summarizes the effect of various types of geometric isomerism on the bioactivity of compounds. In addition, the results of the authors’ own research are presented. In particular, the results of studying the antimicrobial and antifungal activity of hydroxyalkyl monoesters of norbornedicarboxylic acid depending on their stereoisomeric forms in relation to various pathogenic microorganisms are shown. The studies were carried out by the serial dilution method. As nutrient media, we used MPA pH 7,2–7,4 for bacteria and Sabouraud’s medium for fungi. The incubation time in a thermostat for bacteria was 18–24 hours at 37ºC, for fungi 1–10 days at 28ºC. It has been noted that the endo-isomers of the synthesized compounds have a higher antimicrobial and antifungal activity against grampositive (Staphylococcus aureus), gramnegative (Escherichia coli, Pseudomonas aeruginosa) bacteria, as well as yeast-like fungi of the genus Candida. Based on the obtained test reports, the synthesized compounds have been recommended for use as local antiseptic preparations.

The Evolution of Leaf Function during Development Is Reflected in Profound Changes in the Metabolic Composition of the Vacuole

During its development, the leaf undergoes profound metabolic changes to ensure, among other things, its growth. The subcellular metabolome of tomato leaves was studied at four stages of leaf development, with a particular emphasis on the composition of the vacuole, a major actor of cell growth. For this, leaves were collected at different positions of the plant, corresponding to different developmental stages. Coupling cytology approaches to non-aqueous cell fractionation allowed to estimate the subcellular concentrations of major compounds in the leaves. The results showed major changes in the composition of the vacuole across leaf development. Thus, sucrose underwent a strong allocation, being mostly located in the vacuole at the beginning of development and in the cytosol at maturity. Furthermore, these analyses revealed that the vacuole, rather rich in secondary metabolites and sugars in the growth phases, accumulated organic acids thereafter. This result suggests that the maintenance of the osmolarity of the vacuole of mature leaves would largely involve inorganic molecules.

Simple Ion–Gas Mixtures as a Source of Key Molecules Relevant to Prebiotic Chemistry

Very simple chemistry can result in the rapid and high-yield production of key prebiotic inorganic molecules. The two reactions investigated here involve such simple systems, (a) carbon disulfide (CS2) and acetate (CH3COO¯) and (b) sulfur dioxide (SO2) and formate (HCOO¯). They have been carried out under non-aqueous conditions, either in an organic solvent or with a powdered salt exposed to the requisite gas. Under such dry conditions the first reaction generated the thioacetate anion [CH3COS]¯ while the second produced the radical [SO2·]¯anion. Anhydrous conditions are not rare and may have arisen on the early earth at sites where an interface between different phases (liquid/gas or solid/gas) could be generated. This is one way to rationalize the formation of molecules and ions (such as we have produced) necessary in the prebiotic world. Interpretation of our results provides insight into scenarios consistent with the more prominent theories of abiogenesis.

Salt and Water Stress Responses in Plants

Climate change-driven ecological disturbances have a great impact on freshwater availability which hampers agricultural production. Currently, drought and salinity are the two major abiotic stress factors responsible for the reduction of crop yields worldwide. Increasing soil salt concentration decreases plant water uptake leading to an apparent water limitation and later to the accumulation of toxic ions in various plant organs which negatively affect plant growth. Plants are autotrophic organisms that function with simple inorganic molecules, but the underlying pathways of defense mechanisms are much more complex and harder to unravel. However, the most promising strategy to achieve sustainable agriculture and to meet the future global food demand, is the enhancement of crop stress tolerance through traditional breeding techniques and genetic engineering. Therefore, it is very important to better understand the tolerance mechanisms of the plants, including signaling pathways, biochemical and physiological responses. Although, these mechanisms are based on a well-defined set of basic responses, they can vary among different plant species.

Physical Characteristics and Compressive Strength of Na-Geopolymer Paste Designed by a Taguchi Method

Geopolymer paste is a revolutionary building material that the chemical activity of inorganic molecules will create. It is an alternative to traditional Portland cement and is more Eco-friendly. This analysis aimed to classify the mixtures and their process parameters suitable for the development of Geo-polymer paste with one of the ultimate compressive powers, the highest-lowest porosity, and the lowest-lowest final and initial setting time. In the experimental design of the Geo-polymer-based-metakaolin, a Taguchi methodology has been utilized. Five variables parameters were chosen that are mostly to influence the properties of the geopolymer. These are the quantity of Si, alkali, the proportion of alkali reagents, duration of blending, and water amount. These variables’ influence has been calculated at 7 and 28 days on compressive strengths, porosity, density, and setting time. The analysis indicates that the strong compressive strength (115MPa) of Geopolymer paste could be achieved with the formula (1Na2O. Al2O3. 3.8SiO2.xH2O) utilizing suitable processing conditions under which the molar ratio of alkali silicate to alkali hydroxide must be held within the range of 3.25-3.02.

Carbamoyl phosphate and its substitutes for the uracil synthesis in origins of life scenarios

The first step of pyrimidine synthesis along the orotate pathway is studied to test the hypothesis of geochemical continuity of protometabolic pathways at the origins of life. Carbamoyl phosphate (CP) is the first high-energy building block that intervenes in the in vivo synthesis of the uracil ring of UMP. Thus, the likelihood of its occurrence in prebiotic conditions is investigated herein. The evolution of carbamoyl phosphate in water and in ammonia aqueous solutions without enzymes was characterised using ATR-IR, 31P and 13C spectroscopies. Carbamoyl phosphate initially appears stable in water at ambient conditions before transforming to cyanate and carbamate/hydrogenocarbonate species within a matter of hours. Cyanate, less labile than CP, remains a potential carbamoylating agent. In the presence of ammonia, CP decomposition occurs more rapidly and generates urea. We conclude that CP is not a likely prebiotic reagent by itself. Alternatively, cyanate and urea may be more promising substitutes for CP, because they are both “energy-rich” (high free enthalpy molecules in aqueous solutions) and kinetically inert regarding hydrolysis. Energy-rich inorganic molecules such as trimetaphosphate or phosphoramidates were also explored for their suitability as sources of carbamoyl phosphate. Although these species did not generate CP or other carbamoylating agents, they exhibited energy transduction, specifically the formation of high-energy P–N bonds. Future efforts should aim to evaluate the role of carbamoylating agents in aspartate carbamoylation, which is the following reaction in the orotate pathway.

IMPORTANCE OF HUMIC SUBSTANCES FOR STABILIZING SOIL AGGREGATES AND CENTRAL REACTIONS EXPLANATION IN SOIL: A REVIEW

Humic substances have an essential function in soil fertility and are viewed as being of prime importance for soil aggregation stability. Humic substances as part of humus-soil organic matter are chemicals generated from the biomolecules physically, chemical and microbiologically (humifying). It is essential since it is the most pervasive biological material source, which nature knows. Roughly 80 percent of total carbon is produced with terrestrial humic compounds and 60 percent of the water dissolved carbon. During the last three decades there have been challenges in two major approaches, the concept of soil humic substances. Much of the organic aromatic soil originates from the carbon that is frequently known as black carbon (black carbon). However, the detection of benzene polycarboxylic acid markers and the UV technique in soil with two commonly used methods is not trustworthy. Polymerisation of phenolic compounds produced from the breakdown and synthesis of lignin microorganisms may result in a wide number of humic chemicals and components including organic molecules and inorganic molecules. The addition of e.g., triazines or tensile compounds that cause to bound residues in the humic matrix demonstrates that humic substances are crucial for clarifying critical soil processes. Plant nutrients, comprising p, fe and cu, are available in soil this is equally essential to understand and can directly influence the growth of higher plants in the soil.

Nanoscale Cerium Oxide: Synthesis, Biocatalytic Mechanism, and Applications

Nanoscale cerium oxide has excellent catalytic performance due to its unique surface properties and has very important applications in various fields. In this paper, the synthesis methods, catalytic mechanism and activity regulation of nanoscale cerium oxide in recent years are reviewed. Secondly, the application of cerium oxide in the detection of organic and inorganic molecules is summarized, and its latest progress and applications in antibacterial, antioxidant and anticancer are discussed. Finally, the future development prospect of nanoscale cerium oxide is summarized and prospected.