Synthesis, Antioxidant, and Antifungal Activities of ß-Ionone Thiazolylhydrazone Derivatives and Their Application in Anti-Browning of Freshly Cut Potato.

In order to develop a new type of antioxidants with high efficiency, a series of ß-ionone thiazolylhydrazone derivatives were designed and synthesized from ß-ionone, and their structures were characterized by 1H-NMR, 13C-NMR, FT-IR, and HR-MS. The antioxidant test in vitro indicated that most of the target compounds had high biological activity. Among them, compound 1k exhibited very strong DPPH (1,1-diphenyl-2-picrylhydrazyl radical)-scavenging activity with a half-maximal effective concentration (IC50) of 86.525 µM. Furthermore, in the ABTS (2,2-azinobis (3-ethylbenzothiazoline-6-sulfonate) diammonium salt)-scavenging experiment, compound 1m exhibited excellent activity with an IC50 of 65.408 µM. Their biological activities were significantly better than those of the positive control Trolox. These two compounds, which have good free-radical-scavenging activity in vitro, were used as representative compounds in the anti-browning experiment of fresh-cut potatoes. The results showed that 1k and 1m had the same anti-browning ability as kojic acid, and they were effective browning inhibitors. In addition, it is well known that microbial infection is one of the reasons for food oxidation. Therefore, we investigated the antifungal activity of 25 target compounds against eight plant fungi at a concentration of 125 mg/L. The results indicated that these compounds all have some antifungal activity and may become new potential fungicides. Notably, compound 1u showed the best inhibitory effect against Poria vaporaria, with an inhibition rate as high as 77.71%; it is expected to become the dominant structure for the development of new antifungal agents.

Rejecters overestimate the negative consequences they will face from refusal.

People often find it difficult to refuse requests from others partially because they are concern about the negative consequences they will face from saying "no." However, are these concerns well founded? The results from seven studies (N = 2,132) and four supplementary studies (N = 1,470) showed that rejecters overestimated these negative consequences. This overestimation persisted in hypothetical (Studies 1 and 3), real-life (Study 2), and incentivized (Study 4) settings. We also found that this overestimation resulted from a desire to avoid negative consequences. As the cost was sometimes larger for underestimation than for overestimation in refusal, exaggerating the negative outcomes of refusal faced by rejecters may help prepare for or even eliminate them, and eventually satisfy people's desire to avoid negative consequences. If the desire to avoid negative consequences weakened, this overestimation reduced or disappeared (Studies 5-7). (PsycInfo Database Record (c) 2023 APA, all rights reserved).

A CuO-CeO2 composite prepared by calcination of a bimetallic metal-organic framework for use in an enzyme-free electrochemical inhibition assay for malathion.

An enzyme-free electrochemical method is described for the determination of trace levels of malathion. It is based on a nanostructured copper-cerium oxide (CuO-CeO2) composite prepared by calcination of a Cu(II)/Ce(III) metal-organic framework. The morphology, crystal structure and elemental composition of composite was studied by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The principle for malathion determination is based on the fact that the redox signal of CuO (best measured at around -0.1 V vs. SCE) (at 100 mV/s) is inhibited by malathion due to affinity between CuO and the sulfur groups of malathion. The introduction of CeO2 into the composite system further improves the analytical performance. This is attributed to the unique microstructure and the synergistic effect between CuO and CeO2. Experimental parameters like solution pH value, Cu/Ce molar ratio, accumulation potential, accumulation time, and CuO-CeO2 volume on the electrode were optimized. The assay has a linear range of 10 fM to 100 nM and a 3.3 fM detection limit (at S/N = 3). The electrode is selectively inhibited by malathion even in the presence of potentially interfering substances. Graphical abstract A sensitive and effective enzyme-free electrochemical sensor has been developed for the detection of malathion based on CuO-CeO2 composite derived from bimetallic metal-organic frameworks.

High-performance voltammetric sensor for dichlorophenol based on ß-cyclodextrin functionalized boron-doped graphene composite aerogels.

2, 2-methylenebis (4-chlorophenol) (dichlorophenol, Dcp) is a priority pollutant that poses a serious health threat to the public. Thus, the sensitive analysis of Dcp is of great significance. Heteroatom-doped carbon nanomaterials modified electrodes have been proven to be good electrocatalysts for electrochemical sensing application. ß-cyclodextrin (ß-CD) as a signal amplifier has also been utilized in biosensors. Inspired by these, in this study, a new composite of ß-CD and three-dimensional (3D) boron-doped graphene aerogels (BGAs/ß-CD) has been designed as a high-performance electrochemical sensing platform for Dcp determination. Graphene aerogels possess high specific surface area, large pore volume and good conductivity, which ensure rapid mass transfer and accelerated electron transfer. Besides, boron doping causes uneven charge distribution on the graphene lattice surface, producing a large amount of flowing π electrons, which provide abundant active sites for the catalytic oxidation reaction of Dcp. In addition, Dcp molecules could be captured into ß-CD through host-guest recognition, which can effectively amplify the detection signal. Combining the merits of BGAs and ß-CD, the BGAs/ß-CD based sensor achieved sensitive detection of Dcp. Under optimized experimental conditions, the oxidation currents and the concentration of Dcp had a good linear relationship within 1.0 nM âˆ¼ 21 µM. The detection limit was estimated as 0.33 nM (S/N = 3). This study might provide a new basis for the fabrication of 3D BG-based aerogel architectural material and its application in Dcp detection.