Novel Aspects on Chemistry and Biochemistry Vol. 2

This study aimed to improve the Peukert equation so that it can be used for the nickel–metal hydride batteries at any temperature and discharge current. Batteries of various electrochemical systems are used in many technical devices, vehicles and airplanes. For the operation of any technical object containing batteries, it is very important to know the residual capacity of the batteries because the operation du-ration of the whole technical object depends on the residual capacity of the batteries. In this paper, it is experimentally proven that the generalized Peukert equation C(i,T) = C_m(T)/(1 + (i/i₀(T))^n(T)) is applicable to nickel–metal hydride batteries at any discharge currents, while the classical Peukert equation can be used only in a limited range of the discharge currents (approximately from 0.3 C_n to 3 C_n). In addition, the classical Peikert equation does not take into account the influence of the temperature of a battery on its released capacity. It is also proven that for the nickel–metal hydride batteries, the generalized Peukert equation heavily depends on battery temperature (via the parameters C_m(T), i₀(T) and n(T)).The physical significance of the generalised Peukert equation's parameters' temperature dependencies is also established. Any discharge current and battery temperature can be used with the obtained generalised Peukert equation, which takes the batteries' temperature into account. For standby power of communication systems in photovoltaic systems, electric vehicles, etc., nickel-metal hydride batteries are frequently used. Because they are thought to be more environmentally friendly than nickel-cadmium batteries, nickel-metal hydride batteries require accurate calculation models. Many battery models employ the Peukert equation.

In this work, the interaction of 4^'-hydroxychalcone (4^' HC) with bovine serum albumin (BSA) and human serum albumin (HSA) was compared by using steady state absorption and fluorescence spectroscopy, FTIR, circular dichroism and molecular docking. The most abundant protein found in blood plasma is serum albumins having many physiological functions. They are mainly responsible for the absorption, distribution and metabolism of endogenous and exogenous ligands. Bimolecular quenching constants and Stern-Volmer analysis show that BSA exhibits static quenching. However, both static and dynamic quenching mechanisms are responsible for the fluorescence quenching of HSA. Absorption spectroscopy provides additional evidence of the formation of the ground state complex.  The interaction of 4'HC with BSA is stronger than with HSA. FRET study shows the possible energy transfer between 4'HC with BSA and HSA. The binding site of the protein was identified by molecular docking study. Stern-Völmer analysis of the quenching data indicates that the mechanism of quenching for BSA is static quenching and in case of HSA is dynamic quenching. Both of the serum albumins have undergone conformational change, according to the FTIR and CD analyses. According to the thermodynamic analysis, the association of BSA and HSA with 4'HC is spontaneous, enthalpy driving, and involves electrostatic force of interaction.

The environment, both aquatic and terrestrial, is highly polluted with microplastics which are found everywhere across the ecosystem. Microplastics, particles of plastic with a diameter lesser than 5 mm, have become of global environmental concern because they can be transported to far distances and end up in the ecosystems and cause harms to marine life as well as a range of other living things including algae, zooplankton, fish, crabs, sea turtles, birds and human health. The increasing concentration and negative impacts of microplastics on environment and health are further exacerbated by their non-biodegradable nature and has made microplastics to attract attention. In this review, we highlight the sources and fate of microplastics in the environment as well as their transport and methods (destructive and non-destructive) of identification.

The harmful impacts of groundwater pollutants, specifically fluoride and nitrate, on human and animal health are widely recognised on a global scale. The rural regions possess a significant amount of agricultural waste biomass, which can be utilised to generate porous biochar through uncomplicated, eco-friendly, and economical techniques. The current investigation was proposed  for the  utilisation of Peanut shell biomass to produce active carbons through a uncomplicated pyrolytic process. The active carbons were then evaluated for their efficacy in adsorbing fluoride ions from groundwater samples obtained from the Shekhawati region of Rajasthan, India. The production of amorphous porous activated carbon, or PSAC, was carried out through a pyrolytic process with alkaline stimulation and nitrogen flow, reaching a maximum temperature of 550°C. The resulting material exhibited a specific surface area of 479.569 m2/g and a micropore volume of 0.124 cm³/g. A range of spectrometric instruments, such as XRD, FTIR, SEM, EDX, BET, and pH_zpc, were utilised to analyse and characterise the synthesised material. A study was conducted to investigate various adsorption parameters, adsorption isotherms, and kinetic studies through a batch experiment. The study on adsorption indicates that the PSAC demonstrated efficient elimination of fluoride from a solution containing water, exhibiting a sorption capacity of 7.75 mg/gm and 80% effectiveness in removal. The findings of the study on adsorption isotherms indicate that the Freundlich isotherm was the most suitable model for the equilibrium study, as evidenced by a linear regression value of 0.993. The kinetic data were analysed to assess the applicability of the pseudo-first and pseudo-second-order models, as well as the intra-particle diffusion concept. The kinetics investigation revealed that the process of adsorption was consistent with a pseudo-second order reaction. Consequently, it was anticipated that the investigation would enhance and augment the economic exploitation of peanut shell biomass for the purpose of water purification.

Being key structural units for various natural products and privileged scaffolds in medicinal chemistry, functionalized (tetrahydro) quinoline molecules, especially 2,4-diaryl (tetrahydro)quinoline derivatives reveal a wide spectrum of potent, interesting pharmacological activities, and unique physicochemical properties. Their synthetic method is based on the three-component Povarov reaction, in which commercially available substituted anilines and benzaldehydes are involved. The third component, trans (E)-methyl-isoeugenol, an activated dienophile, comes from the essential oil of P. pseudocaryophyllus- (E)-methyl-isoeugenol chemotype- plant, or from eugenol, another phenolic metabolite of the clove oils. In this chapter, we discuss the synthesis of some 4-(3,4-dimethoxyphenyl)-3-methyl-2-phenyl-1,2,3,4-tetrahydroquinolines that have been prepared through the Povarov reaction, and their transformations (N-furoylation reaction and oxidative dehydrogenation aromatization reaction) which led to the formation of new (tetrahydro)quinoline derivatives with alkaloid structure. Intermediate and final products interesting biological models for pharmacological agent research, especially regarding anticancer and antibacterial or antifungal drug design.

The healthy growth of Zea mays (maize) requires nitrogenous fertilizer (NF) as NH₄NO₃. The aim of this research to analyze the effect of consortium: Pichia norvegensis, Saccharomyces cerevisiae, Schizosaccharomyces pombe and Xanthobacter autotrophicus on Zea mays at 70% NH₄NO₃. In that sense experiment with randomized block design, and response variables: germination percentage and days of emergence; phenology: plant height (HP)/root length (RL) and biomass: aerial and root fresh weight (AFW)/(RFW) as well as aerial and root dry weight (ADW/RDW). Experimental data were analyzed by ANOVA/Tukey HSD (P<0.05).The results showed a positive effect of S. cerevisiae and X. autotrophicus on the germination of Z. mays with NH₄NO₃ at 70% with 100%; on phenology and seedling biomass with S. cerevisiae and X. autotrophicus registered 32.83 cm HP, 15.86 cm RL,1.84 g AFW, 1.48 g RFW, 0.27 g ADW and 0.28 g RDW, statistically different numerical values compared to 75% germination, 14.44 cm HP, 9.33 cm RL, 0.42 g AFW, 0.71 g of RFW, 0.04 g of ADW and 0.10 g of RDW of Z. mays without the microbial consortium and the NH₄NO₃ at 100%. The foregoing demonstrates the use of different types of endophytic yeast with X. autotrophicus as a natural option to reduce and  optimize the NF that avoid soil deterioration under agriculture in sustainability scheme.

The present study examined the anti-oxidation and anti-proliferation activity of the two new flavonoids compounds in cancer cells. Cinnamomum species have been used as important sources of traditional medicine, timber, edible fruits, spices, and perfumes in China for a long history. Cinnamoum reticulatum  Hayata (Lauraceae) is an indigenous tree species in Taiwan. We further isolated the two flavonoids compounds kaempferol-3-O-(2",4"-di-E-p-coumaroyl)-\(\alpha\)-L-rhamnopyranoside (1) and kaempferol-3-O-(3",4"-di-E-p-coumaroyl)-\(\alpha\)-L-rhamnopyranoside (2) from the leaves and stems of C. reticulatum Hayate. The phytochemical characteristics, antioxidant and cytotoxic activities of the two compounds were evaluated. Kaempferol-3-O-(2",4"-di-E-p-coumaroyl)-\(\alpha\)-L-rhamnopyranoside (1) and kaempferol-3-O-(3",4"-di-E-p-coumaroyl)-\(\alpha\)-L-rhamnopyranoside (2) have antiproliferation activity in lung cancer cell line (A549 and NCI-H460) and breast cancer cell line (MCF-7 and MDA-MB-231). However, (1) displays better antioxidant activity than (2). Our results showed that the two flavonoids from C. reticulatum might have good potential for further development as chemoprevention or antioxidant remedies. Flavonoids possess anti-oxidative effects as free radical scavengers and metal ion cheaters properties associated with the phenolic hydroxyl groups attached to ring structures. Intensity of the antioxidant activity of a flavonoid strongly depends on its chemical structure.

Pyrazoles are most explored and very important structural analogues of chalcones and have very special place in synthetic medicinal due to its pharmacological importance. Presence of pyrazole ring system in large number of naturally occurring molecules is one of the peculiar characteristics of this heterocyclic system. Inspired by excellent biological activity and structural complexity of pyrazole analogues we are working in area of chalcone and pyrazole synthesis.  By reacting chalcone derivatives with phenylhydrazine, a library of novel dihydropyrazole compounds was created from well-designed Curcumin analogues. All the synthesized compounds were characterized by spectroscopic (¹H and ¹³C NMR, IR spectra), spectrometric (Mass spectra) data and elemental analysis. Due to the presence of optically active carbon in the pyrazole ring, dihydropyrazoles exhibited the characteristic dd (double doublet). All of the synthesized compounds were tested for antifungal activity against six distinct fungal starins.  With MIC (Minimum Inhibitory Concentration) values up to 3.12µg/ml., evaluated heterocyles exhibited strong inhibitory properties against the tested fungal strains.  Antifungal activity was greatest in heterocyles containing nitro and methoxy modifications. SAR has been created between the numerous substitutions at the phenyl ring of produced heterocycles among 20 distinct derivatives assessed for biological activity.

The purpose of this study is to investigate the effectiveness of Pyrolyzed leaves of Custard Apple at 800^oC (OPA) in air and in the presence of inert gas (IGPA) as adsorbent materials for removing fluoride from aqueous solutions. The study examines the impact of various parameters, such as particle size, agitation speed, pH, contact time, adsorbent dosage, initial fluoride concentration, and temperature on the adsorption of fluoride onto Annona squamosa. The results indicate that the highest fluoride removal efficiency was achieved at a pH of 7, a contact period of 30 minutes, an agitation speed of 500 rpm, and an adsorbent dosage of 1.5g per 50 mL of fluoride water. The OPA and IGPA achieved fluoride removal efficiencies of 93% and 96%, respectively. The adsorption isotherm modeling studies revealed that the adsorption onto OPA followed the Dubinin-Raudskevitch isotherm model, while IGPA followed the Langmuir isotherm model. The thermodynamic parameters showed that the reaction is endothermic. The kinetics study revealed that the Pseudo second order model best fit both OPA and IGPA. The SEM, FTIR, and XRD patterns of the adsorbent were analyzed to gain a better understanding of the adsorption mechanism. Overall, the study demonstrates the potential of OPA and IGPA as effective adsorbents for removing fluoride from aqueous solutions.

To solve the water issue, novel wastewater treatment methods are required. The goal of scientists is to create a cheap, simple, and eco-friendly substance to remove pollutants. The use of biochar made from biowaste might perhaps solve the issue of water contamination. The main aim of this chapter is to discuss numerous facets of biochar, such as its sources, characteristics, adsorption mechanism, and uses, particularly in the context of wastewater treatment. Given its unique chemical composition, high porosity, and long-lasting stability, biochar has a lot of potential as a wastewater treatment material. Biochar has grown in importance as environmental degradation persists to worsen and scientists struggle to address contaminants.

The purpose of the research was to determine the mechanism of activation of microbial communities as a result of exposure to a constant electrostatic field. The complex of studies carried out on Biosystems at different values of the field strength and the time spent by cells in the physical field proved that it is possible to obtain both the activation of biochemical processes and the inhibition of the rate of endogenous respiration. The studies were carried out at electrostatic field strengths from 4.0 to 20.0 kV /m and the time the cells were in the physical field from 3.0 to 30.0 seconds. Further, within 2 hours, changes in the medium were recorded in terms of the total volume (output) of the antibiotic concentration and the enzymatic activity of the biocenosis for the case of activation or inhibition observed in the aquatic environment. The processing of the suspension was carried out in an electrostatic unit, which was installed outside the bioreactor. Next, the mixture was again returned to the bioreactor, which made it possible to maintain continuous circulation of the suspension. In parallel, the control system worked, but without a block with an electrostatic field. It was determined that 50% recirculation allows to obtain an acceleration of the oxidation of the intracellular substrate up to 40%, depending on the cellular mycelium. Based on the experimental results obtained, it is proposed to use electrostatic fields to accelerate the second stage of antibiotic biosynthesis, as well as to optimize the processes of oxidation of organic compounds in bioreactors during the biochemical purification of water systems.

The present study report that chiral salicyloxazoline metal complexes can be produced using 1.0 equiv. of copper, cobalt, nickel, manganese, palladium and platinum salts as the third component. The general strategy for creating metal complexes starts with the synthesis of ligands, which is then followed by ligand reactions with metal salts to produce organometallic complexes. Our research group first reported a one-pot mul-ticomponent synthesis of chiral oxazolinyl-zinc complexes, in the presence of a large amount of ZnCl₂ (0.4-2.6 equiv.), with the yields of some products reaching 90%.

The prior strategy was extended to use copper, cobalt, nickel, manganese, palladium or platinum salts as the third component. The one-step method used 1.0 equivalent of a metal salt, such as M(OAc)2·nH2O or MCl2·nH2O 2-cyanophenol with different D-and L-amino alcohols. The proposed mechanism indicates that the excess metal salts can activate the reaction of 2-hydroxybenzo-nitrile with d-phenylglycinol in chlorobenzene to form the ligand intermediates and then directly afford the corresponding organometallic complexes via a one-step procedure.

Complexes 1-8 were obtained using a one-pot method with a sequential strategy. The reaction out-come was demonstrated for three-component reactions between metal salts, amino alcohols and 2-hydroxybenzoni-trile to afford organometallic complexes in good yields (65-95%). Investigations of the catalytic properties of these complexes as chiral ligands are currently ongoing. These complexes have exhibited bioactivities as anticancer rea-gents, and their future use in medical fields are currently under development.