Phenacyl aryl sulfones as synthons for 1,2,3-selenadiazoles and thiadiazoles

1062-106

Sulfonyl pyrazoles and isoxazoles: Cycloaddition of nitrile imines and nitrile oxides to aryl styryl sulfones

1286-128

Nanoencapsulation of Pesticides: Sustainable Perspective in Agriculture

The concern towards the increasing challenges of sustainable agriculture made the researchers towards significant technological development and innovations in recent years. In particular, Nanotechnology offers potential solutions to improve agricultural production assuring sustainability. The incorporation of nanotechnology as a means of nano pesticides delivers the pesticides appropriately i.e., targeted delivery of pesticides by lowering the indiscriminate use of conventional pesticides. The assets of a nanoencapsulated pesticide formulation are controlled releasing properties with enhanced solubility, specificity, permeability and stability. They provide in-built switches to control the release and subsequent availability of pesticides to be used effectively over a given period of time and their design enables them to resist the severe environmental processes such as leaching, evaporation, photolytic hydrolytic and microbial degradation over conventional pesticides. This review provides fundamental information to critically assess the significant role of nanotechnology for the encapsulation of pesticides. © 2020 Author(s)

Phytochemistry and pharmacological activities of the genus Rhynchosia: a comprehensive review

Main conclusion: The genus Rhynchosia is a rich source of natural compounds especially flavonoids and prenylated isoflavonoids. Further experimental studies on Rhynchosia members may be result new and novel secondary metabolites with potent biological activities. Abstract: Traditionally, medicinal plants have played a significant role on human life since ancient days. At present, natural compounds are the major source for the modern drug discovery owing to their therapeutic selectivity, minutest of side effects, inexpensive source and serve as lead molecules for the discovery of new drugs. Rhynchosia species (Fabaceae) are extensively circulated throughout the tropical and subtropical areas around the world. A few plants of this genus were used in traditional medicine for the treatment of various ailments such as antibacterial, antidiabetic, abortifacients, healing of wounds, hepatoprotective, remedial of boils, rheumatic pains and skin infections. The present review compiles traditional uses, isolated chemical compounds and pharmacological activities of Rhynchosia species. So far, in total, seventy-seven compounds were isolated from the genus Rhynchosia, including flavonoids, isoflavonoids, flavan-3-ols, xanthones, biphenyls, simple polyphenols and sterols. It is interesting to note that the genus Rhynchosia is a rich source of C-glycosylflavonoids and prenylated isoflavonoids. Further, phytochemical and pharmacological studies on this genus are required since only few species have been investigated so far. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature

Optimization of medium for the production of subtilisin from Bacillus subtilis MTCC 441

Subtilisins (E.C.3.4.21.62) are alkaline proteases that are secreted by members of the genus Bacillus. They are serine proteases that exhibit high specific activity on proteinaceous substrates, function optimally at moderate temperatures, and are stable under alkaline conditions. Thus the use of subtilisin as an enzyme additive could help in development of quality laundry detergents. In this work the subtilisin production from Bacillus subtilis (MTCC 441) was improved by altering and optimizing the media components. This alteration was brought up by process development strategy. The effect of yeast extract, casein, peptone and sodium chloride on subtilisin production was studied and were optimized using Box Behnken Design. The optimal growth conditions for B. subtilis MTCC 441 were found to 37oC, and pH 7.5. The optimal media composition for subtilisin production was found to beyeast extract at 6.75 g/L, peptone at 4.41 g/L, sodium chloride at 6.08 g/L, casein at 10.75 g/L with glucose at 5 g/L. The predicted and observed response were 181.00 U/mg (with desirability =0.87) and 185.70 U/mg, respectively

Structure-based virtual screening of pseudomonas aeruginosa lpxa inhibitors using pharmacophore-based approach

Multidrug resistance in Pseudomonas aeruginosa is a noticeable and ongoing major obstacle for inhibitor design. In P. aeruginosa, uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) acetyltransferase (PaLpxA) is an essential enzyme of lipid A biosynthesis and an attractive drug target. PaLpxA is a homotrimer, and the binding pocket for its substrate, UDP-GlcNAc, is positioned between the monomer A–monomer B interface. The uracil moiety binds at one monomer A, the GlcNAc moiety binds at another monomer B, and a diphosphate form bonds with both monomers. The catalytic residues are conserved and display a similar catalytic mechanism across orthologs, but some distinctions exist between pocket sizes, residue differences, substrate positioning and specificity. The analysis of diversified pockets, volumes, and ligand positions was determined between orthologues that could aid in selective inhibitor development. Thenceforth, a complex-based pharmacophore model was generated and subjected to virtual screening to identify compounds with similar pharmacophoric properties. Docking and general Born-volume integral (GBVI) studies demonstrated 10 best lead compounds with selective inhibition properties with essential residues in the pocket. For biological access, these scaffolds complied with the Lipinski rule, no toxicity and drug likeness properties, and were considered as lead compounds. Hence, these scaffolds could be helpful for the development of potential selective PaLpxA inhibitors. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.National Natural Science Foundation of China, NSFC: 31171209, 31071152Funding: This research was funded by the National Natural Science Foundation of China (grant numbers: 31071152 and 31171209) to WG

Real-Gas Effects and Phase Separation in Underexpanded Jets at Engine-Relevant Conditions

A numerical framework implemented in the open-source tool OpenFOAM is presented in this work combining a hybrid, pressure-based solver with a vapor-liquid equilibrium model based on the cubic equation of state. This framework is used in the present work to investigate underexpanded jets at engine-relevant conditions where real-gas effects and mixture induced phase separation are probable to occur. A thorough validation and discussion of the applied vapor-liquid equilibrium model is conducted by means of general thermodynamic relations and measurement data available in the literature. Engine-relevant simulation cases for two different fuels were defined. Analyses of the flow field show that the used fuel has a first order effect on the occurrence of phase separation. In the case of phase separation two different effects could be revealed causing the single-phase instability, namely the strong expansion and the mixing of the fuel with the chamber gas. A comparison of single-phase and two-phase jets disclosed that the phase separation leads to a completely different penetration depth in contrast to single-phase injection and therefore commonly used analytical approaches fail to predict the penetration depth.Comment: Preprint submitted to AIAA Scitech 2018, Kissimmee, Florid