scholarly journals The production of enantiomerically pure 1-phenylethanol by enzymatic kinetic resolution method using response surface methodology

2020 ◽  
Vol 44 (5) ◽  
pp. 1352-1365
Author(s):  
Ayşe BOZAN ◽  
Rahime SONGÜR ◽  
Ülkü MEHMETOĞLU
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Response Surface ◽  
High Performance ◽  
Kinetic Resolution ◽  
Enantiomeric Excess ◽  
Reaction Parameters ◽  
Enantiomerically Pure ◽  
Enzymatic Kinetic Resolution ◽  
Optimum Reaction

As the enantiomers of 1-phenylethanol are valuable intermediates in several industries, the lipase catalyzed kinetic resolution of (R,S) -1-phenylethanol is a relevant research topic. In this study, the goal was to determine the optimum reaction parameters to produce enantiomerically pure 1-phenylethanol by lipase (Novozyme 435) catalyzed kinetic resolution using response surface methodology (RSM). Reactions were performed with 40–400 mM (R,S)-1-phenylethanol, 120–1200 mM vinyl acetate and 2–22 mg/ mL biocatalyst concentrations (BCL), at 20–60 °C and with a stirring rate of 50–400 rpm for 5–120 min. The samples were analyzed using high performance liquid chromatography (HPLC) with a Chiralcel OB column. Optimum reaction parameters to reach 100% enantiomeric excess for the substrate (ees) were determined as follows: substrate concentration (Cs): 240 mM, BCL: 11 mg/mL, at 42 °C with a reaction time of 75 min. Model validation was performed using these conditions and ees was calculated as 100%, which indicates the predicted model was efficient and accurate. When compared to the literature, it was observed that the reaction time decreased significantly. This is an important result considering the industrial scale perspective.

scholarly journals Optimization of Synthesis of Seleno-Sargassum fusiforme(Harv.) Setch. Polysaccharide by Response Surface Methodology, Its Characterization, and Antioxidant Activity

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Yu-Bin Ji ◽  
Fang Dong ◽  
Miao Yu ◽  
Long Qin ◽  
Dan Liu
Keyword(s):  
Antioxidant Activity ◽  
Response Surface Methodology ◽  
Reaction Time ◽  
Response Surface ◽  
Reaction Temperature ◽  
Sargassum Fusiforme ◽  
Synthesis Conditions ◽  
Optimum Reaction ◽  
Series Of Experiments

The response surface methodology was employed to optimize the synthesis conditions of seleno-Sargassum fusiforme(Harv.) Setch. polysaccharide. Three independent variables (reaction time, reaction temperature, and ratio of Na2SeO3to SFPSI) were tested. Furthermore, the characterization and antioxidant activity of Se-SFPSIin vivowere investigated. The result showed that the actual experimental Se content of Se-SFPSI was 3.352 mg/g at the optimum reaction conditions of reaction time 8 h, reaction temperature 71°C, and ratio of Na2SeO3to SFPSIB 1.0 g/g. A series of experiments showed that the characterization of Se-SFPSIB was significantly different from that of SFPSIB. Additionally, antioxidant activity assay indicated that the Se-SFPSIB could increase catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activity of mice bearing tumor S180in blood, heart, and liver while decreasing malondialdehyde (MDA) levels. It can be concluded that selenylation is a feasible approach to obtain seleno-polysaccharide which was utilized as highly biological medicine or functional food.

scholarly journals Optimization of the asymmetric synthesis of (S)-1-phenylethanol using Ispir bean as whole-cell biocatalyst

2019 ◽  
Vol 8 (1) ◽  
pp. 525-532 ◽  
Author(s):  
Gunay Baydar Atak ◽  
Emine Bayraktar ◽  
Ülkü Mehmetoglu
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Enantiomeric Excess ◽  
Acetone Powder ◽  
Agitation Rate ◽  
Enantiomerically Pure ◽  
Whole Cells ◽  
Whole Cell Biocatalyst ◽  
Orbital Shaker ◽  
Asymmetric Bioreduction

Abstract In this study, enantiomerically pure (S)-1-phenylethanol was produced via asymmetric bioreduction of acetophenone. Ispir bean (Phaseolus vulgaris) was used as an alcohol dehydrogenase (ADH) source since whole cells are cheaper than isolated enzymes. Acetone powder methodology was applied for biocatalyst. Glucose was used as a cosubstrate in-order to regenerate cofactor (NADPH). The reactions were carried out in an orbital shaker whose temperature and agitation rate can be controlled. (S)-1-phenylethanol concentration was analyzed by HPLC using a Chiralcel OB column. Effects of the reaction time, substrate concentration, cosubstrate concentration and biocatalyst concentration on the (S)-1-phenylethanol production were investigated using Response Surface Methodology (RSM). 36 h bioreduction time, 6 mM acetophenone concentration, 25.15 mM glucose concentration, and 175 mg/mL biocatalyst concentration were determined as optimum values. In these conditions, 2.4 mM (S)-1-phenylethanol was obtained in phosphate buffer (pH=7.0) at 30°C with >99% enantiomeric excess.

Optimization of Magnesium Separation and Extraction from Boron Slurry Using Response Surface Methodology

2011 ◽  
Vol 366 ◽  
pp. 366-369
Author(s):  
Feng Gao ◽  
Rong Fu ◽  
Ming Yang Qian ◽  
Zhu Min Wang ◽  
Xiang Zhang
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Factorial Design ◽  
Response Surface ◽  
Reaction Temperature ◽  
Fractional Factorial Design ◽  
Design Criterion ◽  
Fractional Factorial ◽  
Effective Factors

Response surface methodology was used to optimize the soaking Mg leaching ratio from the boron slurry screened by 25 fractional factorial design. Five effective factors such as H2SO4 concentrations, reaction time, reaction temperature and stir velocity were tested by using 25 fractional factorial design criterion and three effective factors H2SO4 concentrations, reaction time and reaction temperature showed significant effect(P2SO4 concentrations of 0.29mol/l, reaction time of 90 min and reaction temperature of 50°C. Three runs of additional confirmation experiments were conducted. The mixture magnesium leaching value was 58.20%.

scholarly journals Optimization of Enzymatic Synthesis of Betulinic Acid Amide in Organic Solvent by Response Surface Methodology (RSM)

2019 ◽  
Vol 19 (4) ◽  
pp. 849
Author(s):  
Nurul Atikah Amin Yusof ◽  
Nursyamsyila Mat Hadzir ◽  
Siti Efliza Ashari ◽  
Nor Suhaila Mohamad Hanapi ◽  
Rossuriati Dol Hamid
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Response Surface ◽  
Reaction Temperature ◽  
Betulinic Acid ◽  
Enzymatic Synthesis ◽  
Acid Amide ◽  
Molar Ratio ◽  
Percentage Yield ◽  
Substrate Molar Ratio

Optimization of the lipase catalyzed enzymatic synthesis of betulinic acid amide in the presence of immobilized lipase, Novozym 435 from Candida antartica as a biocatalyst was studied. Response surface methodology (RSM) and 5-level-4-factor central-composite rotatable design (CCRD) were employed to evaluate the effects of the synthesis parameters, such as reaction time (20–36 h), reaction temperature (37–45 °C), substrate molar ratio of betulinic acid to butylamine (1:1–1:3), and enzyme amounts (80–120 mg) on the percentage yield of betulinic acid amide by direct amidation reaction. The optimum conditions for synthesis were: reaction time of 28 h 33 min, reaction temperature of 42.92 °C, substrate molar ratio of 1:2.21, and enzyme amount of 97.77 mg. The percentage yield of actual experimental values obtained 65.09% which compared well with the maximum predicted value of 67.23%. The obtained amide was characterized by GC, GCMS and 13C NMR. Betulinic acid amide (BAA) showed a better cytotoxicity compared to betulinic acid as the concentration inhibited 50% of the cell growth (IC50) against MDA-MB-231 cell line (IC50 < 30 µg/mL).

scholarly journals Optimization and Modeling of Microcystin-LR Degradation by TiO2 Photocatalyst Using Response Surface Methodology

2020 ◽  
Author(s):  
Negar Jafari ◽  
Afshin Ebrahimi ◽  
Karim Ebrahimpour ◽  
Ali Abdolahnejad
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Removal Efficiency ◽  
Contact Time ◽  
High Performance ◽  
Operating Variables ◽  
Effective Removal ◽  
Positive Effect ◽  
Harmful Effects ◽  
Maximum Removal

Introduction: Microcystin-leucine arginine (MC-LR) is a toxin with harmful effects on the liver, kidney, heart, and gastrointestinal tract. So, effective removal of MC-LR from water resources is of great importance. The aim of this study was to remove microcystin-LR (MC-LR) from aqueous solution by Titanium Dioxide (TiO2). Materials and Methods: In the present study, TiO2, as a semiconductor, was used for photodegradation of MC-LR under ultraviolet light (UV). The Response Surface Methodology was applied to investigate the effects of operating variables such as pH (A), contact time (B), and catalyst dose (B) on the removal of MC-LR. The MC-LR concentration was measured by high-performance liquid chromatography (HPLC). Results: The results showed that single variables such as A, B, and C had significant effects on MC-LR removal (pvalue < 0.05). In other words, increase of the contact time and catalyst dose had a positive effect on enhancing the removal efficiency of MC-LR, but the effect of pH was negative. The analysis of variance showed that BC, A2, and C2 variables had a significant effect on the MC-LR removal (pvalue < 0.05). Finally, the maximum removal efficiency of MC-LR was 95.1%, which occurred at pH = 5, contact time = 30 minutes, and catalyst dose = 1 g/l. Conclusion: According to the findings, TiO2, as a photocatalyst, had an appropriate effect on degradation of the MC-LR.

scholarly journals Synthesis of enantiomerically pure alcohols and amines via biocatalytic deracemisation methods

2019 ◽  
Vol 9 (20) ◽  
pp. 5487-5503 ◽  
Author(s):  
Musa M. Musa ◽  
Frank Hollmann ◽  
Francesco G. Mutti
Keyword(s):  
Kinetic Resolution ◽  
Enantiomeric Excess ◽  
Enantiomerically Pure ◽  
Theoretical Maximum

Deracemisation via chemo-enzymatic or multi-enzymatic approaches is the optimum substitute for kinetic resolution, which suffers from the limitation of a theoretical maximum 50% yield albeit high enantiomeric excess is attainable.

Optimization of Synthesis Technology of Acetylferrocene by Response Surface Methodology

2012 ◽  
Vol 622-623 ◽  
pp. 162-165
Author(s):  
Da Wei Yin ◽  
Gang Tao Liang ◽  
Xiao Ming Sun ◽  
Yu Ting Liu
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Response Surface ◽  
Acetyl Chloride ◽  
Raw Materials ◽  
Raw Material ◽  
Interactive Effects ◽  
Percentage Yield ◽  
Experimental Yield ◽  
Central Composite

Acetylferrocene was synthesized by acetyl chloride and ferrocene as raw materials, dichloromethane as the solvent, and ZnO as catalyst. Response surface methodology based on three-level, three-variable central composite rotable design was used to evaluate the interactive effects of the ratio of acetyl chloride and ferrocene(2-4), the amount of ZnO(1.0-1.3mol), reaction time(30-60 min)on the percentage yield of acylferrocene. The optimal raw material ratio, amount catalyst, and reaction time was 3:1, 1.19mol, 40min. Under the optimum conditions, the actual experimental yield can reach 86.72%.

scholarly journals Rhizomucor miehei Lipase Supported on Inorganic Solids, as Biocatalyst for the Synthesis of Biofuels: Improving the Experimental Conditions by Response Surface Methodology

Energies ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 831 ◽  
Author(s):  
Juan Calero ◽  
Diego Luna ◽  
Carlos Luna ◽  
Felipa Bautista ◽  
Beatriz Hurtado ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Silica Gel ◽  
Rhizomucor Miehei ◽  
Rhizomucor Miehei Lipase ◽  
Reaction Parameters ◽  
Experimental Conditions ◽  
Inorganic Solids ◽  
Lipozyme Rm Im ◽  
Miehei Lipase

Two inorganic solids have been evaluated as supports of Lipozyme RM IM, a Rhizomucor miehei lipase immobilized on a macroporous anion exchange resin, in order to improve its application as a biocatalyst in the synthesis of biofuels. The experimental conditions have been optimized to get the selective transesterification of sunflower oil, by using a multi-factorial design based on the response surface methodology (RSM). In this way, the effects of several reaction parameters on the selective ethanolysis of triglycerides to produce Ecodiesel, a biodiesel-like biofuel constitute by one mole of monoglyceride (MG) and two moles of fatty acid ethyl ester (FAEE), have been evaluated. Thus, it was obtained that a 6:1 oil/ethanol molar ratio, 0.215 g of biocatalyst supported in silica-gel (0.015 g Lipase/0.2 g silica-gel), 50 µL of 10 N NaOH, together with previous optimized reaction parameters, 35 °C reaction temperature and 120 min of reaction time, gave the best results (conversions around 70%; selectivity around 65%; kinematic viscosities about 9.3 mm2/s) in the reaction studied. Besides, Lipozyme RM IM, supported on silica-gel, biocatalyst exhibited a very good stability, remaining its activity even after 15 cycles.

Sign in / Sign up

Export Citation Format

Share Document