SPE-HPLC Determination of Chlorogenic and Phenolic Acids in Coffee

A new solid phase extraction-high-performance liquid chromatography method with ultraviolet detection was developed and validated for the determination of three chlorogenic acids (5-O-caffeoylquinic, 3-O-caffeoylquinic and 4-O-caffeoylquinic acids) and six phenolic acids (caffeic, ferulic, sinapic, protocatechuic, p-hydroxybenzoic acid (PHBA) and vanillic acid (VA)) in coffee bean samples. Extraction was performed using hydrophilic-lipophilic balance cartridges. Separations were accomplished using a C-18 guard column (10 x 2.1 mm, 3 mu m) and a C18 analytical column (50 x 2.1 mm, 3 mu m). o-Phosphoric acid solution (0.08%) and methanol/water/acetonitrile (85: 10: 5) solution were used as mobile phase with a gradient system. A UV detector was used at 325 nm for 5-O-caffeoylquinic, caffeic, 3-O-caffeoylquinic, 4-O-caffeoylquinic, ferulic, sinapic acids, and 215 nm for protocatechuic, PHBA and VA. Calibration equations and coefficients of determination were determined by least-squares method with weighting factor. Limits of detection and quantification were in the range of 0.15-0.69 and 0.46-2.09 mg/L, respectively. Precision and accuracy of the proposed method were investigated with coffee sample spiked at low, medium and high concentrations. The developed and validated method was applied for the determination of nine phenolic compounds in seven coffee bean samples from different origins with high accuracy and repeatability

Coupling ion exchange with ultrafiltration for boron removal from geothermal water-investigation of process parameters and recycle tests

A hybrid process was established in a stirred vessel coupling ion exchange with ultrafiltration (UF). Boron selective chelating ion-exchange resins Dowex XUS-43594.00 with an average particle diameter of 20 mu m were used for boron separation from geothermal water and a submerged hollow fiber type UF membrane module (ZW-1, GE) was used for the filtration of the resin suspension and collecting permeate. Process variables such as the concentration of ion exchange resin in the suspension, replacement rates of fresh and saturated resins in the stirred vessel, and flow rate of permeate were evaluated in order to determine the efficiency of the hybrid process for boron removal from geothermal water. The recycle performance of the hybrid system was monitored following ten sorption-washing-elution-washing-regeneration-washing cycles. (C) 2013 Elsevier B.V. All rights reserved

Utilization of geothermal water as irrigation water after boron removal by monodisperse nanoporous polymers containing NMDG in sorption-ultrafiltration hybrid process

WOS: 000353094300007A relatively new method of polymerization, 'modified seeded polymerization' has been used for the synthesis of monodisperse nanoporous poly(glycidyl methacrylate-co-ethylene dimethacrylate) and poly(vinylbenzyl chloride-co-divinylbenzene) beads. The synthesized polymer beads were then functionalized with N-methyl-D-glucamine (NMDG) to obtain boron selective resins. The efficiency of these particles for boron removal from geothermal water was investigated by using the hybrid process coupling sorption with ultrafiltration (UF) method where a submerged hollow fiber type UF membrane module was employed for filtration. It was possible to reduce the boron concentration from 11.0 mg/L to <= 1 mg/L in 20 min with hybrid method using poly(glycidyl methacrylate-co-ethylene dimethactylate)-NMDG beads with 4 g-resin/L-geothermal water. The respective period for poly(vinylbenzyl chloride-co-divinylbenzene) beads with the same resin dosage was 30 min. In the case of commercially available boron selective ion exchange resin Dowex-XUS 43594.00 ground to an average particle size of 20 pm, the target boron concentration which is mg/L was reached in 20 mm by using 2 g-resin/L-geothermal water. (C) 2015 Elsevier B.V. All rights reserved.National Boron Research Institute, BORENMinistry of Energy & Natural Resources - Turkey [2008-G-0192]; TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK)This work was supported financially by the National Boron Research Institute, BOREN (Project Number: 2008-G-0192). We are grateful also to TUBITAK for the post-doc fellowship to Dr. S. Samatya. We thank E. Guler for the kind help to run hybrid tests. We thank Dow Chemical Co. for sending us boron selective resins Dowex-XUS-43594.00 as a gift

Utilization of geothermal water as irrigation water after boron removal by monodisperse nanoporous polymers containing NMDG in sorption-ultrafiltration hybrid process

A relatively new method of polymerization, 'modified seeded polymerization' has been used for the synthesis of monodisperse nanoporous poly(glycidyl methacrylate-co-ethylene dimethacrylate) and poly(vinylbenzyl chloride-co-divinylbenzene) beads. The synthesized polymer beads were then functionalized with N-methyl-D-glucamine (NMDG) to obtain boron selective resins. The efficiency of these particles for boron removal from geothermal water was investigated by using the hybrid process coupling sorption with ultrafiltration (UF) method where a submerged hollow fiber type UF membrane module was employed for filtration. It was possible to reduce the boron concentration from 11.0 mg/L to <= 1 mg/L in 20 min with hybrid method using poly(glycidyl methacrylate-co-ethylene dimethactylate)-NMDG beads with 4 g-resin/L-geothermal water. The respective period for poly(vinylbenzyl chloride-co-divinylbenzene) beads with the same resin dosage was 30 min. In the case of commercially available boron selective ion exchange resin Dowex-XUS 43594.00 ground to an average particle size of 20 pm, the target boron concentration which is mg/L was reached in 20 mm by using 2 g-resin/L-geothermal water. (C) 2015 Elsevier B.V. All rights reserved

An innovative integrated system for boron removal from geothermal water using RO process and ion exchange-ultrafiltration hybrid method

WOS: 000317945300001In this study, removal of boron from the geothermal water was investigated by an integrated process coupling reverse osmosis (RO) with ion exchange-ultrafiltration hybrid method. Desalination tests were performed by using a mini-pilot scale brackish water reverse osmosis (BWRO) system which was installed at Yenikale Geothermal Heating Center, Izmir. Boron selective chelating ion exchange resin Dowex (XUS 43594.00) with a particle size of 20 mu m was employed for removal of boron from BWRO permeate of geothermal water. A submerged hollow fiber type ultrafiltration membrane module (ZW-1) was used for filtration. Effect of such process variables as resin concentration in the suspension, flow rates of fresh and saturated ion exchange resins, and flow rate of permeate on the efficiency of the hybrid process for boron removal from RO permeate of geothermal water was studied. (C) 2013 Elsevier B.V. All rights reserved.National Boron Research Institute of Turkey, BORENMinistry of Energy & Natural Resources - Turkey [2008-G-0192]This study was supported by the National Boron Research Institute of Turkey, BOREN (Project no. 2008-G-0192). We thank Izmir Geothermal Energy Co. for the kind permission and support to perform RO tests in the geothermal heating center. We also acknowledge Dow Chem. for sending us boron selective ion exchange resin Dowex XUS-43594.00. We are grateful to Prof. M. Bryjak, Wroclaw University of Technology, Poland for his great encouragement on the subject research. We appreciate also reviewers for their kind comments and suggestions to improve this manuscript

Separation of Boron from Geothermal Water Using a Boron Selective Macroporous Weak Base Anion Exchange Resin

In this study, batch and column mode tests were performed to evaluate the efficiency of boron removal from geothermal water containing 10-11mgB/L using Lewatit MK 51 which is a macroporous weak base anion exchange resin with polyhydroxyl groups showing a very high selectivity and capacity for boron. The optimum resin amount for boron removal from geothermal water was determined as 4.0g resin/L-geothermal water. It was found that the sorption kinetics was influenced by particle size of the resin and temperature. The stirring rate had almost no effect on kinetic performance of the resin. According to the results of column-mode study performed, breakthrough and total capacities of the resin were obtained as 2.75 and 4.98mg/mL-resin, respectively

Characterization of the Chemical Profile of Euphorbia Species from Turkey by Gas Chromatography-Mass Spectrometry (GC-MS), Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS), and Liquid Chromatography-Ion Trap-Time-of-Flight-Mass Spectrometry (LC-IT-TOF-MS) and Chemometric Analysis

The Euphorbiaceae family comprises of about 300 genera and 5000 species primarily distributed in America and tropical Africa. The Euphorbia genus is represented by 105 species and locally named as "Sutlegen" and "Xasil" in Turkey. The present study aimed to determine the chemical constituents of E. aleppica, E. eriophora, E. macroclada, E. grisophylla, E. seguieriana subsp. seguieriana, E. craspedia, E. denticulata, E. falcata, and E. fistulosa, and classify them by utilizing the chemometric techniques of principal component analysis (PCA) and hierarchical cluster analysis (HCA). Linoleic acid, 17-tetratriacontane, palmitic acid, and hexatriacontane were the major fatty acids from the gas chromatography-mass spectrometry (GC/MS) analyses. Characterization of 268 constituents of the studied species was achieved by liquid chromatography-ion trap-time-of-flight-mass spectrometry (LC-IT-TOF-MS). Furthermore, a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous quantitative determination of 11 compounds (quinic acid, protocatechuic acid, rutin, hesperidin, eugenol, p-coumaric acid, piceatannol, scopoletin, dl-kavain, chrysophanic acid, and resiniferatoxin) in these species. The developed method was validated for the linearity, limit of detection, limit of quantification, repeatability, and recovery