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Fluoride, a naturally occurring chemical element, is largely insoluble in soils. More than 90% of the fluoride in soil is bound to soil particles and is unable to be dissolved. As part of the soil, fluoride is predominantly located in the colloid or clay fraction of the soil, and the movement of fluoride is strongly affected by the sorption capacity of the soil, which is affected by pH, the type of soil sorbent present, and the salinity. The Canadian Council of Ministers of the Environment soil quality guideline for fluoride in soils under a residential/parkland land use scenario is 400 mg/kg. In this review, we focus on fluoride contamination in soil and subsurface environments, and the various sources of fluorides are discussed in detail. The average fluoride concentration in soil in different countries and their regulations for soil and water are comprehensively reviewed. In this article, the latest advances in defluoridation methods are highlighted and the importance of further research addressing efficient and cost-effective methods to remediate fluoride contamination in soil is critically discussed. Methods used to mitigate fluoride risks by removing fluoride from the soil are presented. We strongly recommend that regulators and soil chemists in all countries explore opportunities to improve defluoridation methods and consider adopting more stringent regulations for fluoride in soil depending on geologic conditions. [Display omitted] • Fluoride in soil and subsurface environments are discussed. • Sources of fluoride in soil/water and their effects are overviewed. • Soil quality parameters for residential land use in various countries are summarized. • Recent advances in defluoridation methods in soil are highlighted. • Globally organized various mitigation programs are presented. [ABSTRACT FROM AUTHOR]

Abstract: Steroidal thiazolidinone derivatives were prepared by the multi-step reactions of steroid. It is prepared from steroidal thiosemicarbazones with ethyl bromoacetate in dioxane. Steroidal thiosemicarbazones were prepared by the reaction of thiosemicarbazide with steroidal ketones. The structures of these compounds were elucidated by IR, 1H NMR, Fab mass spectrometries and their purities were confirmed by elemental analyses. The antibacterial activity of these compounds was evaluated by the disk diffusion assay against two Gram-positive and two Gram-negative bacteria and then the minimum inhibitory concentration (MIC) of compounds was determined. The results showed that steroidal thiazolidinone derivatives are better in inhibiting the growth as compared to steroidal thiosemicarbazone derivatives of both types of the bacteria (Gram-positive and Gram-negative). Compounds 7 and 8 are better antibacterial agents as compared to standard drug Amoxicillin. [Copyright &y& Elsevier]

• GO was synthesized, reduced to GN by ascorbic acid. • The removal of Congo red (CR) and Acid green 25 (AG25) using GN-MnO 2 was studied for the first time. • The whole adsorption process was investigated systematically. • The adsorption mechanism were revealed and elucidate in detail. • CR and AG25 have high adsorption capacities and rapid kinetics on GN-MnO 2. Graphene nanosheet-manganese dioxide (GN-MnO 2) composite was synthesized by a microwave-assisted method. The physico-chemical properties of modified graphene (GN) were characterized by different techniques, such as scanning electron microscopes (SEM), Fourier-transform infrared spectrometers (FTIR), X-ray diffraction (XRD) and Raman spectroscopy. The effects of contact time, pH, concentration, temperature, and the dose of adsorbent on the adsorption attributes of Congo red (CR) and Acid green 25 (AG25) on GN-MnO 2 composite was studied. The experimental facts of the isotherm were found to be more fitted with the Langmuir isotherm rather than the Freundlich one, while the pseudo-second-order kinetic model/curve was found to be fitted with experimental data, giving an indication that the experiment was controlled by chemical processes. The maximum adsorption capacities is derived from the Langmuir model equation at 303 K were 270.06 and 324.26 mg/g for CR and AG25, respectively. The thermodynamic study revealed that the adsorption of CR and AG25 dyes onto the GN-MnO 2 was pretty much spontaneous in nature and showed that the GN-MnO 2 was a decent adsorbent for the elimination of CR and AG25 ions in aqueous conditions. The column studies were conducted in varying flowrates (4−12 mL/min), and bed heights (0.5–1.5 cm), with a concentration of 100 mg/L, while at pH of 3 and 4 for CR and AG25, respectively. The adsorption capability increased with the increasing influent level and column depth while it was reduced by upturn in flow-rate. The results obtained were fitted well with the Bed Depth Service Time BDST and Thomas models. [ABSTRACT FROM AUTHOR]

Abstract: The incretin based therapies are emerging class of antidiabetic drugs having two categories one is glucagone like peptide-1 (GLP-1) agonists and another one is dipeptidyl peptidase (CD26; DPP-IV) inhibitors. However, in DPP-IV inhibitors category only few compounds are commercially available and also having some undesirable effects. Therefore, in the present work we tried to explore a naturally occurring compound naringin for its potential DPP-IV inhibition and antidiabetic potential. It is noteworthy that this compound is abundantly present in the peels of Orange and thus may provide cost effective treatment for diabetes especially type 2 diabetes mellitus. In the present study we have conducted virtual docking study and observed tight binding of naringin, as shown by higher negative values of H Bond lengths, while in vitro DPP-IV inhibition assay has also shown better inhibition by naringin. In vivo study, in response to 10days administration of 40mg/kg of naringin twice daily to Wistar albino rats, inhibited the serum levels of DPP-IV activity, random glucose concentration with concomitant increase in insulin levels. All the comparisons were made with the standard commercially available drug sitagliptin. [Copyright &y& Elsevier]