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The reaction between 6-methyl-4-phenylamino-pyran-2-one and aroyl chlorides with potassium thiocyanate in the presence of catalytic amounts of N-methylimidazole under solvent-free conditions provided a simple and efficient one-pot route for the synthesis of 2-aryl-7-methyl-1-phenyl-4-thioxo-1,4-dihydro-pyrano[4,3-d]pyrimidin-5-one. This new protocol offers advantages such as mild reaction conditions, short reaction time, easy work-up, high yields of biological active products and does not involve any hazardous solvent. [ABSTRACT FROM AUTHOR]

A significant range of intriguing nanomaterials includes photocatalytic and antibacterial nanocomposites, which exhibit great efficacy in water treatment. In this work, Euphorbia hebecarpa extract was used as a novel natural reducing agent to investigate the environmentally friendly production of ZnO@β-cyclodextrin (CD) nanoparticles (NPs). In the following, polyacrylonitrile, ZnO@β-CD and chitosan nanofibers were electrospun concurrently using a dual-electrospinning process to create a unique nano-biosorbent made of polyacrylonitrile (PAN)--ZnO@β-CD--chitosan (CS) nanofibrous nanocomposite. Additionally, this nanocomposite's effectiveness as a novel photocatalyst and antibacterial agent for eliminating organic dyes like methylene blue was evaluated. Field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) analysis, Fourier-transform infrared (FTIR) spectroscopy and Raman spectroscopy (RS) were used to analyze the structure of the nanocomposite. The outcomes verified the production of ZnO@β-CD, which had evenly shaped particles with an average size of 45 nm on the nanofibrous matrix. This nanocomposite exhibited removal efficiency of methylene blue of ~90% after 105 min at pH 7 and 2.5 g L-1 nanocomposite concentration. Furthermore, an antibacterial test revealed that PAN--ZnO@β-CD--CS nanofibrous nanocomposite with 6% ZnO showed over 80% reduction in colony-forming units per millilitre against Bacillus cereus, Staphylococcus epidermidis and Streptococcus iniae. [ABSTRACT FROM AUTHOR]

We studied the lethal and sublethal effects of essential oils (EOs) of Allium sativum L. and Vitex pseudo-negundo (Hausskn) on Tetranychus urticae Koch. Based on LC50 concentrations, A. sativum (19.2 µL/L air) was more toxic than V. pseudo-negundo (51.9 µL/L air). To assess the sublethal effects, adult mites were exposed to the LC10 and LC30 of each EO. Exposure to LC30 of A. sativum and V. pseudo-negundo negatively affected the development, survival, fecundity, and fertility of T. urticae F1 generation, as well as general esterase and MFO enzymes activity. These concentrations affected the detoxification enzyme activity of treated mites. [ABSTRACT FROM AUTHOR]

1,3-Oxazine derivatives have found versatile applications as antibacterial and cancer-screening agents.[1] They have antifungal action and are used as herbicides.[2],[3] The thio derivatives of pyrano-1,3-benzoxazine have shown anti-inflammatory and antipyretic properties.[4] Multi-component reactions (MCRs) are now frequently used by synthetic organic chemists as a facile means to generate molecular diversity from bifunctional substrates that react sequentially in an intramolecular fashion,[5] and this approach may be used for the preparation of oxazines. Thus, under reaction conditions similar to those previously described,[18] an acyl chloride B 2 b was reacted with potassium selenocyanate B 3 b under solvent-free conditions at ambient temperature and then warmed at 90 °C for 5 min prior to the addition of 7-hydroxy-3-coumaranone B 1 b . The mass spectra of compounds B 4a-f b are fairly similar and display molecular ion peaks. For example, the mass spectrum of compound B 4a b showed a molecular ion peak at I m/z i 387 confirming that compound B 4a b is a condensation product of 7-hydroxy-3-coumaranone, 4-nitrobenzoyl chloride and potassium selenocyanate. [Extracted from the article]

A non-enzymatic electrochemical sensor (modified carbon paste electrode (CPE) using La2O3–Co3O4 nanocomposite and ionic liquid) was made for sensitive quantification of hydrazine. The scanning electron microscopic (SEM), X-ray powder diffraction (XRD) as well as Fourier transform infrared spectroscopy (FT-IR) were employed for finding the nanocomposite characteristics. The electrochemical measurements revealed that combination of La2O3–Co3O4 nanocomposite and ionic liquid and carbon paste showed very good voltammetric responses toward hydrazine oxidation with the broad linear ranges between 0.1 and 120.0 μM and low detection limit (DL) of 0.01 μM, and 203.6 μA mM−1 cm−2 sensitivity. Then, hydrazine in different water samples was determined by the standard addition procedure. We observed reasonable findings with relative standard deviation (RSD) of less than 3.4% and 96.0–103.0% recovery for 5 parallel measurements. Hence, La2O3–Co3O4/CPE can be considered as one of the novel platforms for hydrazine to be electrochemically detected. [ABSTRACT FROM AUTHOR]

This study aimed at pre-concentrating Allura Red as a food additive dye and determining it in the environmental samples following its extraction. Dispersive solid-phase extraction was followed by UV-Vis spectroscopy to provide a simple and efficient method with low cost by using silver- zirconium oxide nanoparticles loaded on an activated carbon as the adsorbent. The proposed adsorbent was simply prepared and characterized by different techniques, such as Fourier-transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. Evaluation and optimization of the effective parameters on the extraction recovery, including eluent volume (mL), pH, adsorbent dosage (mg), and ultrasound time (min), and their interactions were investigated using a response surface methodology based on a central composite design as an efficient mathematical and statistical tool. The selected model's precision and accuracy were assessed through the analysis of variance, while the optimum conditions were obtained as follows: eluent volume = 0.3 mL, pH = 3, adsorbent dosage = 10 mg, and ultrasound time = 4.5 min. Under the optimum operational conditions, the limit of quantification of 75.0 ng mL-1, limit of detection of 26.0 ng mL-1, and linear range of 80.0-5,000 ng mL-1 were achieved. A high correlation coefficient was obtained via the Langmuir isotherm as best model, from which the maximum adsorption capacity of 52.40 mg g-1 was resulted. [ABSTRACT FROM AUTHOR]

The present studywas designed to synthesize lanthanum doped feathers-typeZnOnano-flower (feathers-type La3+-ZnO nano-flower), that are specified via Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). To simultaneously determine codeine and diclofenac using feather-type La3+-ZnO nano-flower modified carbon paste electrode (La3+-ZnO/CPE), an original cost-efficient and simple methodology is presented. Evidently, La3+-ZnO/CPE proved to be a prospective, stable, sensitive and chemically reliable electrochemical sensor to determine diclofenac and codeine simultaneously with no intervention or overlapping of voltammetric peaks or signals. Codeine electroanalytical sensing was examined via La3+-ZnO/CPE across an extensive concentration range at a relatively low detection limit of 0.01µM, (3S/N). La3+-ZnO/CPE of nanoscale feathers-type La3+-ZnO structure displays favorable practicality in analytical terms to accurately and simultaneously determine diclofenac and codeine within real specimens with exceptional recoveries. The outcomes prove exceptional La3+-ZnO/CPE performance in regard to facile, reliability and sensing capabilities which may favorably decrease the relevant processing expenses for routine analysis and scalable production. [ABSTRACT FROM AUTHOR]

Background: Organophosphate pesticides are one of the most extensively applied insecticides in agriculture. These insecticides persist in the environs and thereby cause severe pollution problems. Iron oxide polymer nanocomposites are wastewater remediation agents synthesized by various methods. When compared to chemical processes, green synthesis using plant extract is thought to be more cost- and environmentally-friendly., Objectives: This study aimed to evaluate the green synthesis of Fe 3 O 4 @β-Cyclodextrin (Fe 3 O 4 @β-CD) nanoparticles using Ferulago angulata ( F. angulata ) methanol extract. These nanoparticles are loaded on polylactic acid (PLA) nanofibrous nanocomposite along with Ferulago angulata extract (2, 4, and, 6wt %) to produce PLA/Fe 3 O 4 @β-CD/ F. angulata extract nanofibrous nanocomposite as a new nano biosorbent. Furthermore, the antibacterial properties of this compound and its activity in diazinon removal have been evaluated., Materials and Methods: Fe 3 O 4 @β-CD nanoparticles synthesis was performed via co-precipitation method using FeCl 3 .6H 2 O and FeCl 2 .4H 2 O and β-cyclodextrin, and Ferulago angulata extract. Then polylactic acid/ Fe 3 O 4 @β-CD / F. angulate.extract nanofibrous nanocomposite was prepared by the electrospinning method. Energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), vibrating sample magnetometer (VSM), and Fourier transform infrared spectroscopy (FTIR) were used to analyze the structure of the nanocomposite. The antibacterial activity of this nanocomposite against several fish and human bacterial pathogens, as well as its effectiveness in diazinon elimination, have been evaluated in the sections that follow., Results: The nanocomposite structure demonstrated that Fe 3 O 4 nanoparticles were produced and put into the polylactic acid matrix with an average particle size of 40 nm. Furthermore, the results showed that this nanocomposite exhibited removal efficiency of diazinon over 80% after 120 minutes under pH=7 and 2.5 gr.L -1 nanocomposite concentration. Also, this structure showed above 70% antibacterial ability against Bacillus cereus, Staphylococcus epidermidis and 60% antibacterial ability against Streptococcus iniae and Yersinia ruckeri ., Conclusion: Fe 3 O 4 nanocomposite synthesis may be accomplished in a delicate and efficient manner by using Ferulago angulata to produce Fe 3 O 4 @-CD nanoparticles. The stability of the nanoparticles was enhanced by combining Ferulago angulata extract with polylactic acid nanofibers to create an antibacterial homocomposition nanocomposite. This device may be used to remove and disinfect diazinon from aqueous media in an environmentally friendly manner., (Copyright: © 2021 The Author(s); Published by Iranian Journal of Biotechnology.)