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Highlights • A facile hydrothermal method was used for the synthesis of binary and ternary metal hydroxide. • The removal of oxytetracycline (OTC) antibiotic using prepared metal hydroxide was studied. • Electrostatic interaction and anion exchange were mainly responsible for the removal of the OTC. • The adsorption of OTC was endothermic in nature and maximum adsorption capacity was found to be 250.07 mg/g. Pharmaceuticals are emerging pollutants present mainly in industrial and municipal wastewater. Herein, structurally variable binary and ternary metal hydroxides based on copper, manganese, and aluminum were used for the adsorptive scavenging of the oxytetracycline (OTC) antibiotic. A facile hydrothermal method was used for the synthesis of binary CuAl-hydroxide, MnAl-hydroxide, and ternary CuMnAl-hydroxide. Structural and morphological characteristics of the metal hydroxides (MHs) were studied by X-ray diffraction (XRD), Fourier transformed infrared spectrum (FTIR), X-ray photoelectron spectroscopy (XPS) and Scanning electron microscopy (SEM) analysis. The adsorptive removal for OTC was found in the order CuMnAl-hydroxide > CuAl-hydroxide > MnAl-hydroxide. The highest removal of OTC by CuMnAl-hydroxide and CuAl-hydroxide was observed at pH 7 while MnAl-hydroxide showed the optimum adsorption at pH 9. All three materials showed different saturation time and equilibrium concentration for OTC adsorption. The mechanism investigation found that strong electrostatic attraction, hydrogen bonding, and anion exchange were mainly responsible for the removal of the OTC and adsorption process followed the pseudo-second-order kinetic model and equilibrium data was best fitted to the Langmuir isotherm model. The adsorption of OTC was influenced by the presence of Cu (II) and Cr (VI) ions in the aqueous solution due to the competitive adsorption of co-ions. Moreover, the adsorption of OTC was endothermic in nature, and maximum adsorption capacity was found to be 250.07 mg/g at 50 °C. [ABSTRACT FROM AUTHOR]

Berry quality, antioxidant compounds, antioxidant capacity and enzymes activity of ‘El-Bayadi’ table grapes cultivar at harvest as affected by preharvest spray of salicylic acid (SA, 4.0 mM) and gibberellic acid (GA 3 , 30 mg/L) were evaluated during 2014 and 2015 seasons. GA 3 spray increased berry weight, length and width compared to SA and control treatments. SA spray decreased berry length and width compared to control. Both cluster weight and length increased by SA and GA 3 compared to control. TSS content was not affected by treatments, but was higher in 2015 than 2014 season. Titratable acidity was higher at GA 3 and SA treatments than control and was higher in 2014 than 2015 season. TSS/acid ratio was lower at SA than GA 3 and control treatments. Berry firmness was lower at SA than GA 3 and control treatments and was higher in 2014 than 2015 season. Total phenols and flavonoids concentrations were higher at SA and GA 3 treatments than control. trans -resveratrol concentration increased, while trans -piceid decreased by SA spray compared to GA 3 and control treatments. Total phenols concentration was higher in 2015 than 2014 season, in contrast to total flavonoids and trans -resveratrol. Vitamin C concentration increased by GA 3 spray compared to SA and control and was higher in 2015 season than 2014. Peroxidase (POD) polyphenoloxidase (PPO), polygalacturonase (PG) and xylanase activities increased by GA 3 spray compared to SA and control. While, SA spray decreased both POD and PPO activities compared to control. Both SA and GA 3 spray lowered antioxidant capacity (higher DPPH IC 50 values) than control. Nitrogen, phosphorus and potassium, and protein concentrations were higher at SA and GA 3 treatments than control. In conclusion, preharvest spray of SA and GA 3 could be used to improve the overall quality ‘El-Bayadi’ table grapes. [ABSTRACT FROM AUTHOR]