The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Esra Isik - One of the best experts on this subject based on the ideXlab platform.

  • optimisation of ultrasonic assisted extraction of antioxidant compounds from artemisia absinthium using Response Surface Methodology
    Food Chemistry, 2013
    Co-Authors: Saliha şahin, Onder Aybastier, Esra Isik
    Abstract:

    Abstract Response Surface Methodology was used to optimise experimental conditions for ultrasonic-assisted extraction of phenolic compounds from Artemisia absinthium. The central composite design was employed, the extracts were characterised by the determination of total phenolic content and antioxidant capacity. The total phenolic contents of extracts were determined by Folin method and also total antioxidant capacities of extracts were determined by ABTS and CUPRAC methods. The phenolic compounds of A. absinthium at optimum extraction conditions were determined by HPLC-DAD. The optimum conditions were determined as HCl concentration between 0.41 and 0.44 mol/L, methanol volume between 55% and 59% (v/v), extraction temperature between 64 and 70 °C, extraction time between 101 and 107 min. The experimental values agreed with those predicted within a 95% confidence level, thus indicating the suitability of Response Surface Methodology in optimising the ultrasound-assisted extraction of phenolic compounds from A. absinthium.

  • optimization of ultrasonic assisted extraction of antioxidant compounds from blackberry leaves using Response Surface Methodology
    Industrial Crops and Products, 2013
    Co-Authors: Onder Aybastier, Saliha şahin, Esra Isik, Cevdet Demir
    Abstract:

    Abstract Response Surface Methodology was used to optimize experimental conditions for ultrasonic-assisted extraction of phenolic compounds from blackberry leaves. The Box-Behnken design (BBD) was employed for the optimization of extraction parameters in terms of total phenolics and antioxidant capacity. The optimal conditions for results of ABTS and CUPRAC were HCl concentration 0.41 and 0.45 M, methanol concentration 61 and 64% (v/v), extraction temperature 66 and 68 °C and extraction time 105 and 117 min, respectively. The experimental values agreed with those predicted values within a 95% confidence level, thus indicating the suitability of Response Surface Methodology in optimizing the ultrasound-assisted extraction of phenolic compounds from blackberry leaves. The results showed that phenolic compounds present in blackberry leaves exhibited significant antioxidant properties. Seven phenolic compounds such as ellagic acid, caffeic acid, chlorogenic acid, quercetin, myricetin, kaempferol and kaempferol 3-β- d -glucopyranoside were determined in blackberry leaves by HPLC-DAD after extraction at optimum conditions.

Onder Aybastier - One of the best experts on this subject based on the ideXlab platform.

  • optimisation of ultrasonic assisted extraction of antioxidant compounds from artemisia absinthium using Response Surface Methodology
    Food Chemistry, 2013
    Co-Authors: Saliha şahin, Onder Aybastier, Esra Isik
    Abstract:

    Abstract Response Surface Methodology was used to optimise experimental conditions for ultrasonic-assisted extraction of phenolic compounds from Artemisia absinthium. The central composite design was employed, the extracts were characterised by the determination of total phenolic content and antioxidant capacity. The total phenolic contents of extracts were determined by Folin method and also total antioxidant capacities of extracts were determined by ABTS and CUPRAC methods. The phenolic compounds of A. absinthium at optimum extraction conditions were determined by HPLC-DAD. The optimum conditions were determined as HCl concentration between 0.41 and 0.44 mol/L, methanol volume between 55% and 59% (v/v), extraction temperature between 64 and 70 °C, extraction time between 101 and 107 min. The experimental values agreed with those predicted within a 95% confidence level, thus indicating the suitability of Response Surface Methodology in optimising the ultrasound-assisted extraction of phenolic compounds from A. absinthium.

  • optimization of ultrasonic assisted extraction of antioxidant compounds from blackberry leaves using Response Surface Methodology
    Industrial Crops and Products, 2013
    Co-Authors: Onder Aybastier, Saliha şahin, Esra Isik, Cevdet Demir
    Abstract:

    Abstract Response Surface Methodology was used to optimize experimental conditions for ultrasonic-assisted extraction of phenolic compounds from blackberry leaves. The Box-Behnken design (BBD) was employed for the optimization of extraction parameters in terms of total phenolics and antioxidant capacity. The optimal conditions for results of ABTS and CUPRAC were HCl concentration 0.41 and 0.45 M, methanol concentration 61 and 64% (v/v), extraction temperature 66 and 68 °C and extraction time 105 and 117 min, respectively. The experimental values agreed with those predicted values within a 95% confidence level, thus indicating the suitability of Response Surface Methodology in optimizing the ultrasound-assisted extraction of phenolic compounds from blackberry leaves. The results showed that phenolic compounds present in blackberry leaves exhibited significant antioxidant properties. Seven phenolic compounds such as ellagic acid, caffeic acid, chlorogenic acid, quercetin, myricetin, kaempferol and kaempferol 3-β- d -glucopyranoside were determined in blackberry leaves by HPLC-DAD after extraction at optimum conditions.

Saliha şahin - One of the best experts on this subject based on the ideXlab platform.

  • optimisation of ultrasonic assisted extraction of antioxidant compounds from artemisia absinthium using Response Surface Methodology
    Food Chemistry, 2013
    Co-Authors: Saliha şahin, Onder Aybastier, Esra Isik
    Abstract:

    Abstract Response Surface Methodology was used to optimise experimental conditions for ultrasonic-assisted extraction of phenolic compounds from Artemisia absinthium. The central composite design was employed, the extracts were characterised by the determination of total phenolic content and antioxidant capacity. The total phenolic contents of extracts were determined by Folin method and also total antioxidant capacities of extracts were determined by ABTS and CUPRAC methods. The phenolic compounds of A. absinthium at optimum extraction conditions were determined by HPLC-DAD. The optimum conditions were determined as HCl concentration between 0.41 and 0.44 mol/L, methanol volume between 55% and 59% (v/v), extraction temperature between 64 and 70 °C, extraction time between 101 and 107 min. The experimental values agreed with those predicted within a 95% confidence level, thus indicating the suitability of Response Surface Methodology in optimising the ultrasound-assisted extraction of phenolic compounds from A. absinthium.

  • optimization of ultrasonic assisted extraction of antioxidant compounds from blackberry leaves using Response Surface Methodology
    Industrial Crops and Products, 2013
    Co-Authors: Onder Aybastier, Saliha şahin, Esra Isik, Cevdet Demir
    Abstract:

    Abstract Response Surface Methodology was used to optimize experimental conditions for ultrasonic-assisted extraction of phenolic compounds from blackberry leaves. The Box-Behnken design (BBD) was employed for the optimization of extraction parameters in terms of total phenolics and antioxidant capacity. The optimal conditions for results of ABTS and CUPRAC were HCl concentration 0.41 and 0.45 M, methanol concentration 61 and 64% (v/v), extraction temperature 66 and 68 °C and extraction time 105 and 117 min, respectively. The experimental values agreed with those predicted values within a 95% confidence level, thus indicating the suitability of Response Surface Methodology in optimizing the ultrasound-assisted extraction of phenolic compounds from blackberry leaves. The results showed that phenolic compounds present in blackberry leaves exhibited significant antioxidant properties. Seven phenolic compounds such as ellagic acid, caffeic acid, chlorogenic acid, quercetin, myricetin, kaempferol and kaempferol 3-β- d -glucopyranoside were determined in blackberry leaves by HPLC-DAD after extraction at optimum conditions.

Cevdet Demir - One of the best experts on this subject based on the ideXlab platform.

  • optimization of ultrasonic assisted extraction of antioxidant compounds from blackberry leaves using Response Surface Methodology
    Industrial Crops and Products, 2013
    Co-Authors: Onder Aybastier, Saliha şahin, Esra Isik, Cevdet Demir
    Abstract:

    Abstract Response Surface Methodology was used to optimize experimental conditions for ultrasonic-assisted extraction of phenolic compounds from blackberry leaves. The Box-Behnken design (BBD) was employed for the optimization of extraction parameters in terms of total phenolics and antioxidant capacity. The optimal conditions for results of ABTS and CUPRAC were HCl concentration 0.41 and 0.45 M, methanol concentration 61 and 64% (v/v), extraction temperature 66 and 68 °C and extraction time 105 and 117 min, respectively. The experimental values agreed with those predicted values within a 95% confidence level, thus indicating the suitability of Response Surface Methodology in optimizing the ultrasound-assisted extraction of phenolic compounds from blackberry leaves. The results showed that phenolic compounds present in blackberry leaves exhibited significant antioxidant properties. Seven phenolic compounds such as ellagic acid, caffeic acid, chlorogenic acid, quercetin, myricetin, kaempferol and kaempferol 3-β- d -glucopyranoside were determined in blackberry leaves by HPLC-DAD after extraction at optimum conditions.

Hyunsung Park - One of the best experts on this subject based on the ideXlab platform.

  • modelling and optimization of a gma welding process by genetic algorithm and Response Surface Methodology
    International Journal of Production Research, 2002
    Co-Authors: Dongcheol Kim, Sehun Rhee, Hyunsung Park
    Abstract:

    The welding process, due to its complexity, has relied on empirical and experimental data to determine its welding conditions. However, trial-and-error methods to determine optimal conditions incur considerable time and cost. In order to overcome these problems, a genetic algorithm and Response Surface Methodology have been suggested for determining optimal welding conditions. First, in a relatively broad region, near-optimal conditions were determined through a genetic algorithm. Then, the optimal conditions for welding were determined over a relatively small region around these near-optimal conditions by using Response Surface Methodology. In order to give different objective function values according to the positive or negative Response from the set target value in the optimization problem, a desirability function approach was used. Application of the method proposed in this paper revealed a good result for finding the optimal welding conditions in the gas metal arc (GMA) welding process.