1.Application of pH-zone refining hydrostatic countercurrent chromatography (hCCC) for the recovery of antioxidant phenolics and the isolation of alkaloids from Siberian barberry herb.
Kukula-Koch W1, Koch W2, Angelis A3, Halabalaki M4, Aligiannis N5. Food Chem. 2016 Jul 15;203:394-401. doi: 10.1016/j.foodchem.2016.02.096. Epub 2016 Feb 15.
The development of a fast hCCC method tailored to recover phenolics of Siberian barberry (Berberis sibirica, Berberidaceae) responsible for the observed strong antioxidant activity was performed. Initially, the optimization of extraction procedure was evaluated based on the antiradical potential assessment (DPPH and Folin-Ciocalteu assays). 100°C methanol ASE extract exhibited the highest antiradical activity (IC50=60±4μg/mL), and a significant TPC (159±2mgGAE/g). Thorough determination of phenolic content by UHPLC-DAD-ESI(-)HRMS revealed the presence of 10 phenolics as major constituents, and several groups of alkaloids. pH-zone refining hCCC was chosen as the most promising method for the extract's fractionation due to the ionizable character of its constituents. For this purpose a MtBE-H2O (1:1) system with 10mM TEA and HCl was applied leading to a phenolic fraction, free of alkaloids, with higher antioxidant capacity (IC50=25μg/mL, TPC=178mgGAE/g).
2.Laboratory Investigation of Three Distinct Emissions Monitors for Hydrochloric Acid.
Dene CE1, Pisano JT2, Durbin TD2, Bumiller K2, Crabbe K3, Muzio LJ4. J Air Waste Manag Assoc. 2016 Mar 2. [Epub ahead of print]
The measurement of hydrochloric acid (HCl) on a continuous basis in coal-fired plants is expected to become more important if HCl standards become implemented as part of the Federal Mercury and Air Toxics Standards (MATS) standards that are under consideration. For this study, the operational performance of three methods/instruments, including tunable diode laser absorption spectroscopy (TDLAS), cavity ring down spectroscopy (CRDS), and Fourier transform infrared (FTIR) spectroscopy, were evaluated over a range of real-world operating environments. Evaluations were done over an HCl concentration range of 0 to 25 ppmV and temperatures of 25°C, 100°C, and 185°C. The average differences with respect to temperature were 3.0% for the TDL for values over 2.0 ppmV and 6.9% of all concentrations, 3.3% for the CRDS, and 4.5% for the FTIR. Interference tests for H2O, SO2, and CO, CO2, and NO for a range of concentrations typical of flue gases from coal-fired power plants did not show any strong interferences.
3.Rapid methods for extracting and quantifying phenolic compounds in citrus rinds.
Magwaza LS1, Opara UL2, Cronje PJ3, Landahl S4, Ortiz JO4, Terry LA4. Food Sci Nutr. 2015 Oct 1;4(1):4-10. doi: 10.1002/fsn3.210. eCollection 2016.
Conventional methods for extracting and quantifying phenolic compounds in citrus rinds are time consuming. Rapid methods for extracting and quantifying phenolic compounds were developed by comparing three extraction solvent combinations (80:20 v/v ethanol:H2O; 70:29.5:0.5 v/v/v methanol:H2O:HCl; and 50:50 v/v dimethyl sulfoxide (DMSO):methanol) for effectiveness. Freeze-dried, rind powder was extracted in an ultrasonic water bath at 35°C for 10, 20, and 30 min. Phenolic compound quantification was done with a high-performance liquid chromatography (HPLC) equipped with diode array detector. Extracting with methanol:H2O:HCl for 30 min resulted in the optimum yield of targeted phenolic acids. Seven phenolic acids and three flavanone glycosides (FGs) were quantified. The dominant phenolic compound was hesperidin, with concentrations ranging from 7500 to 32,000 μg/g DW. The highest yield of FGs was observed in samples extracted, using DMSO:methanol for 10 min.
4.Bipolar membrane electrodialysis for generation of hydrochloric acid and ammonia from simulated ammonium chloride wastewater.
Li Y1, Shi S2, Cao H3, Wu X4, Zhao Z3, Wang L5. Water Res. 2016 Feb 1;89:201-9. doi: 10.1016/j.watres.2015.11.038. Epub 2015 Nov 22.
Simulated ammonium chloride wastewater was treated by a lab-scale bipolar membrane electrodialysis for the generation of HCl and NH3·H2O and desalination. The influence of initial concentration of NH4Cl, current density, salt solution volume, initial concentration of acid and base and membrane stack structure on the yields of HCl and NH3·H2O was investigated. The current efficiency and energy consumption were also examined under different conditions. The results showed that, at the current density of 48 mA/cm(2), the highest concentration of HCl and NH3·H2O with initial concentration of 110 g/L NH4Cl was 57.67 g/L and 45.85 g/L, respectively. Higher initial concentration of NH4Cl was favor to reduce unit energy consumption and increase current efficiency of the BMED system. The membrane stack voltage of BMED increased quickly under constant current when the concentration of NH4Cl contained in the solution of salt compartment was depleted below the "inflection point concentration" about 8000 mg/L.
