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501.
Surekha Kumari Shudh Kirti Dolma Anmol Upendra Sharma S. G. Eswara Reddy 《Molecules (Basel, Switzerland)》2022,27(3)
Aphis craccivora Koch is a polyphagous and major pest of leguminous crops causing significant damage by reducing the yield. Repeated application of synthetic insecticides for the control of aphids has led to development of resistance. Therefore, the present study aimed to screen the insecticidal activity of root/stem extracts/fractions, and pure molecules from Cissampelos pareira Linnaeus against A. craccivora for identification of lead(s). Among root extract/fractions, the n-hexane fraction was found most effective (LC50 = 1828.19 mg/L) against A. craccivora, followed by parent extract (LC50 = 2211.54 mg/L). Among stem extract/fractions, the n-hexane fraction (LC50 = 1246.92 mg/L) was more effective than the water and n-butanol fractions. Based on GC and GC-MS analysis, among different compounds identified in the n-hexane fraction of root and stem, ethyl palmitate (known to possess insecticidal activity) was present in the highest concentration (24.94 to 52.95%) in both the fractions. Among pure molecules, pareirarineformate was found most effective (LC50 = 1491.93 mg/L) against A. craccivora, followed by cissamine (LC50 = 1556.31 mg/L). Parent extract and fractions of C. pareira possess promising activity against aphid. Further, field bio-efficacy studies are necessary to validate the current findings for the development of botanical formulation. 相似文献
502.
Improved graphitic carbon nitride (g-C3N4) was synthesized through a unique one-step cost-effective technique involving a dynamic gas bubbling phenomenon using ammonium chloride (NH4Cl) as a bubbling agent. An extensive investigation was carried out to optimize the weight ratio of NH4Cl and melamine during the thermal pyrolysis process. Here, we report an improved form of g-C3N4 namely “expanded g-C3N4” with increased interlayer distance and remarkable volume expansion. The surface area of this improved version has notably increased leading to higher photocatalytic efficiency as compared with its counterpart, an synthesized without adding NH4Cl. Synthesized photocatalyst materials were further used to study the Rhodamine B photodegradation under visible light. It was observed that the expanded g-C3N4 showed a 2.4 times higher photodegradation rate than its counterpart and degraded 94% of the dye in just 30 min. 相似文献
503.
Deepak Kumar Sharma Athira Suresh Rachana Kumari Sidhikh Kumar Divya Bajpai Tripathy 《Macromolecular Symposia》2024,413(1):2200205
Most people utilize cosmetics to enhance or improve their physical appearance, regardless of their gender, race, or age. Heavy metals (HMs) are impurities or ingredients in many cosmetic products. According to recent studies, these metals can result in a variety of skin and health issues. Numerous studies demonstrate that the mismanaged formulation of such products without sufficient standardization of toxic metals throughout the production process is the primary reason for the high level of HM contamination in the samples. In order to prevent human exposure to such dangerous HMs, it is vital to monitor and manage the fate of HMs in cosmetic items, especially unbranded ones. Due to the wasteful interest of producers in making extra profit, the standards are not being imposed. Moreover, consumers are also ready to compromise with the product due to their unawareness of its hazardous impact on their skin and bodies. Short-term results on their looks may cause fatal effects on their health. Another significant issue that requires attention is the lack of safety regulations in the country for evaluating HMs in cosmetic products. Additionally, there is an urgent need to establish acceptable limits for potential impurities in cosmetic products that must be enforced at local levels. This review provides a comprehensive insight into the content of HMs in cosmetics and their effects on several organs and the site of application. 相似文献
504.
In the present study, poly(N-Isopropylacrylacrylamide-co-N-tertiarybutylacrylamide-co-hydroxyethylcrylamide) (NIPAM-co-NTBA-co-HEAAm) hydrogels are prepared with variation of molar ratio of hydrophilic HEAAm and hydrophobic NTBA. The prepared hydrogels are characterized with elemental analysis and Fourier transform infrared (FTIR) spectroscopy. The thermodynamics of swelling properties of poly(NIPAM-co-NTBA-co-HEAAm) hydrogels have also been discussed. The experimental C/N ratios are comparable with the theoretical value. The enthalpy change of mixing ∆Hmix, entropy change of mixing ∆Smix, free energy change of mixing ∆Gmix are determined for swelling of hydrogels at 25 °C. The value of total free energy of hydrogel swelling is found to be negative which confirms the lower critical solution temperature (LCST) exhibited in all hydrogels and the volume change transition shows the thermoresponsive behavior. The values of ∆Smix increase and ∆Gmix decrease with increasing amount of hydrophobic NTBA content in the hydrogels. The values of free energy change of elasticity (∆Gel) are found to be increased with increasing the hydrophobic NTBA content followed by decrease in swelling percentage. Also, the transition temperature of the hydrogel is found to be decreased with increasing the hydrophobic NTBA. 相似文献
505.
Avnesh Kumari Sudesh Kumar Yadav Yogesh B. Pakade Vineet Kumar Bikram Singh Abha Chaudhary Subhash Chandra Yadav 《Colloids and surfaces. B, Biointerfaces》2011,82(1):224-232
The plant isolated antioxidant quercitrin has been encapsulated on poly-d,l-lactide (PLA) nanoparticles by solvent evaporation method to improve the solubility, permeability and stability of this molecule. The size of quercitrin-PLA nanoparticles is 250 ± 68 nm whereas that PLA nanoparticles is 195 ± 55 nm. The encapsulation efficiency of nanoencapsulated quercitrin evaluated by HPLC and antioxidant assay is 40%. The in vitro release kinetics of quercitrin under physiological condition reveals initial burst release followed by sustained release. Less fluorescence quenching is observed with equimolar concentration of PLA encapsulated quercitrin than free quercitrin. The presence of quercitrin specific peaks on FTIR of five times washed quercitrin loaded PLA nanoparticles provides an extra evidence for the encapsulation of quercitrin into PLA nanoparticles. These properties of quercitrin nanomedicine provide a new potential for the use of such less useful highly active antioxidant molecule towards the development of better therapeutic for intestinal anti-inflammatory effect and nutraceutical compounds. 相似文献
506.
Dr. Soumen Dutta Akshay Gurumoorthi Shinbi Lee Sun Woo Jang Dr. Nitee Kumari Yu-Rim Hong Prof. Dr. Wonyong Choi Prof. Dr. Chang Yun Son Prof. Dr. In Su Lee 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303890
Herein, by choosing few-nm-thin two-dimensional (2D) nanocrystals of MOF-5 containing in-planner square lattices as a modular platform, a crystal lattice-guided wet-chemical etching has been rationally accomplished. As a result, two attractive pore patterns carrying Euclidean curvatures; precisely, plus(+)-shaped and fractal-patterned pores via ⟨100⟩ and ⟨110⟩ directional etching, respectively, are regulated in contrast to habitually formed spherical-shaped random etches on MOF surface. In agreement with the theoretical calculations, a diffusion-limited etching process has been optimized to devise high-yield of size-tunable fractal-pores on the MOF surface that tenders for a compatibly high payload of catalytic ReI-complexes using the existing large edge area once modified into a free amine-group-exposed inner pore surface. Finally, on benefiting from the long-range fractal opening in 2D MOF support structure, while loaded on an electrode surface, a facilitated cross-interface charge-transportation and well-exposure of immobilized ReI-catalysts are anticipated, thus realizing enhanced activity and stability of the supported catalyst in photoelectrochemical CO2-to-CO reduction. 相似文献
507.
Varaprasad Bodala Rajitha Lakshmi Podugu Kumari Yettula Dr. Padmarao Gollamudi Dr. Siddaiah Vidavalur Dr. Shyamala Pulipaka 《化学:亚洲杂志》2023,18(1):e202201004
A direct access to unsymmetrical and symmetrical multi-substituted pyridines has been accomplished via iron-catalysed [3+3] annulation of oxime acetates with enaminones. This protocol is featured by easily available starting materials, no requirement of expensive additives and ligands, operational simplicity, and good tolerance with diverse functional groups. 相似文献
508.
509.
A one‐pot four component condensation of isatin, sarcosine, 2‐[2‐oxo‐1‐(prop‐2‐ynyl)indolin‐3‐ylidene]malononitrile and aryl azides has been reported for the synthesis of novel dispirooxindole pyrrolidine linked 1,2,3‐triazole conjugates using Cu(I) as a catalyst in PEG‐400 by stereoselective [3 + 2] azide‐alkyne cycloaddition followed by [3 + 2] azomethine ylide and alkene cycloaddition. Structures have been confirmed by spectral and X‐ray studies. Crystal packing of 5a has also been reported. Rapid reaction, easy work‐up and high yields are the salient features of the present protocol. 相似文献