Search

In this work, the Pb adsorption and removal ability of biochar from simulated Pb(II)-contaminated wastewater, adsorption isotherms, kinetics, and thermodynamics were studied. Adsorption characteristics of biochar on Pb(II) were analyzed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscope with energy dispersive spectrometer (SEM-EDS). The influence of the pH of the solution, the contact time, and the biochar dose on the removal of Pb(II) were investigated by single-factor design and response surface analysis. With the increase in biochar dose from 2 g/L to 4 g/L in wastewater, the Pb(II) amount adsorbed on biochar reduced from 21.3 mg/g to 17.5 mg/g. A weakly acidic environment was more conducive to the ligand exchange between Pb(II) ions and biochar. Pb(II) adsorption kinetics of biochar showed that the Pseudo-first-order model was more suitable than other employed models to describe the adsorption process. During the isothermal adsorption process, Langmuir and Freundlich’s isotherms fitted the adsorption data very well (R2 > 96%). The Pb (II) adsorption onto biochar was spontaneous in the specified temperature range (298–318 K) and the process was exothermic. Simultaneously, the optimal conditions were a pH of 5, a contact time of 255 min, and a biochar dose of 3 g/L, under which the maximum predicted Pb(II) removal efficiency was 91.52%.

RNAi technology, known as a revolutionary technology in the history of pesticides, has been identified as a very promising novel approach for crop protection, which is of great significance for achieving the sustainable agricultural development of the United Nations Food and Agriculture Organization. Although many studies have shown that RNA biopesticides have strong application prospects, its stability seriously restricts the commercial use. As the core component of RNAi, double-stranded RNA (dsRNA) is unstable in its natural form. Therefore, how to ensure the stability of dsRNA is one of the most significant challenges in realizing the commercial use of RNA biopesticides. Nanomaterials such as cationic polymers and lipofectamine can improve the stability of dsRNA in the environment, which has been proved. This paper reviews the recent research progress of nanomaterials that can be used to improve the environmental stability of dsRNA, and discusses the advantages and limitations of different nanomaterials combined with dsRNA, which provides reference for the selection of dsRNA nanoformulations.

New auxinic herbicide derivatives with high-activity and low-volatility are required urgently to solve the growing problems of weed resistance and volatile drifting which severely limit the application of auxinic herbicides (2,4-D, MCPA and dicamba). In this study, a series of auxinic herbicide derivatives were prepared using 2,4-D, MCPA and dicamba as lead compounds by me-too method. The volatility, greenhouse herbicidal activity against four common weeds and field herbicidal activity were evaluated and a comparative analysis with the corresponding lead compound was made. Results of volatility test indicated that it was possible to get a low-volatile compound even when the reactants were both highly volatile and the compounds with intermolecular hydrogen bond showed the comparatively low volatility. In the greenhouse herbicidal activity test, the compounds with ester bond had faster and higher herbicidal activities and better inhibition phenotypes than the compounds with amide bond. The compounds (R)-ethyl 2-(4-(2-(2,4-dichlorophenoxy)acetoxy)phenoxy)propanoate (3a-9), (R)-ethyl 2-(4-(2-(4-chloro-2-methylphenoxy)acetoxy)phenoxy)propanoate (3a-18) and (R)-4-((1-ethoxy-1-oxopropan-2-yl)oxy)phenyl 3,6-dichloro-2-methoxybenzoate (3b-7) showed lower volatilities and faster and higher activities in the greenhouse and field test than the corresponding lead compound and could be potential herbicides for further development. Keywords: Auxinic herbicide derivative, Herbicidal activity, Volatility, Me-too method

In order to develop agents with superior chemopreventive and chemotherapeutic properties against hepatocellular carcinomas, mitochondria-targeted hydroxycinnamic acids (MitoHCAs) were synthesized by conjugation with a triphenylphosphonium cation. These synthetic compounds were evaluated for their antioxidant activities in hepatic mitochondria, including against OH∙− and ROO∙− induced lipid peroxidation. H2O2 production was decreased significantly by increasing glutathione peroxidase and catalase activities. In addition, cell proliferation data from three cell lines (HepG2, L02 and WI38) indicated that the MitoHCAs were selective for cancer cells. Interestingly, the MitoHCAs both with or without Ca2+ triggered mitochondrial dysfunction by inducing mitochondrial swelling, collapsing the mitochondrial membrane potential and causing cytochrome c release. In particular, an inhibitor of the mitochondrial permeability transition pore (mPTP), cyclosporin A, attenuated mitochondrial damage and cell apoptosis, indicating that mPTP may be involved in the antiproliferative activity of MitoHCAs. Further studies focused on structural optimization of these compounds are onging.

Trehalose is a non-reducing disaccharide composed of glucose molecules connected by α-glycosidic bond. this soluble substance plays an important role of protecting green algie and other lower plants from stress. It can help plants cope with extreme environments such as severe cold, drought and high salinity, regulate the stomalal conductance and water utilization rate of plants, and participate in the growth and metabolism regulation of plants as a signal molecule. As an impermeable eryoproteetant, trehalose is widely used in the refrigeration protection of various animal cells and tissues due to its non-toxicity and high efficiency. According to the research results at home and abroad in recent years, the protection, regulation and mechanism of trehalose on plant tissues and animal cells were summarized, so as to provide a theoretical basis for the further development and utilization of trehalose. [ABSTRACT FROM AUTHOR]