scholarly journals Modeling, Simulation, and Kinetic Studies of Solvent-Free Biosynthesis of Benzyl Acetate

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Vijay Kumar Garlapati ◽  
Annapurna Kumari ◽  
Paramita Mahapatra ◽  
Rintu Banerjee

Solvent-free biosynthesis of benzyl acetate through immobilized lipase-mediated transesterification has been modeled and optimized through statistical integrated artificial intelligence approach. A nonlinear response surface model has been successfully developed based on central composite design with transesterification variables, namely, molarity of alcohol, reaction time, temperature, and immobilized lipase amount as input variables and molar conversion (%) as an output variable. Statistical integrated genetic algorithm optimization approach results in an optimized molar conversion of 96.32% with the predicted transesterification variables of 0.47 M alcohol molarity in a reaction time of 13.1 h, at 37.5°C using 13.31 U of immobilized lipase. Immobilized lipase withstands more than 98% relative activity up to 6 recycles and maintains 50% relative activity until 12 recycles. The kinetic constants of benzyl acetate, namely,KmandVmaxwere found to be 310 mM and 0.10 mmol h−1 g−1, respectively.

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Vijay Kumar Garlapati ◽  
Rintu Banerjee

The synthesis of methyl butyrate and octyl acetate through immobilized Rhizopus oryzae NRRL 3562 lipase mediated transesterification was studied under solvent-free conditions. The effect of different transesterification variables, namely, molarity of alcohol, reaction time, temperature, agitation, addition of water, and enzyme amount on molar conversion (%) was investigated. A maximum molar conversion of 70.42% and 92.35% was obtained in a reaction time of 14 and 12 h with the transesterification variables of 0.6 M methanol in vinyl butyrate and 2 M octanol in vinyl acetate using 80 U and 60 U immobilized lipase with the agitation speed of 200 rpm and 0.2% water addition at 32°C and 36°C for methyl butyrate and octyl acetate, respectively. The immobilized enzyme has retained good relative activity (more than 95%) up to five and six recycles for methyl butyrate and octyl acetate, respectively. Hence, the present investigation makes a great impingement in natural flavour industry by introducing products synthesized under solvent-free conditions to the flavour market.


Author(s):  
Syamsul Kamar Muhamad ◽  
Salina Mat Radzi ◽  
Siti Salhah Othman ◽  
Mohd Basyaruddin Abdul Rahman ◽  
Hanina Mohd Noor

The effects of important reaction parameters for enhancing flavour esters formation through lipase-catalyzed reaction were investigated in this study.Various commercial immobilized lipases were used to catalyze the esterification reaction between short-chain fatty acids and alcohols to produce flavour esters which are nonyl caprylate and ethyl valerate which differ in chain length of esters. These synthetic flavour esters with fruity notes are widely used in food, cosmetic and pharmaceutical industries. The effect of various reaction parameters was optimized to obtain a high yield of flavour esters. A maximum percentage for nonyl caprylate with conversion of flavour esters more than 90 % in a solvent-free system was successfully obtained under the following conditions: reaction time (RT), 5 hours; reaction temperature, 40 °C; amount of immobilized lipase, 25 % w/w of total substrate and shaking speed 200 rpm. Compared to ethyl valerate, a maximum percentage conversion of flavour ester more than 80 % in solvent free system was successfully obtained under following conditions: reaction time (RT), 45 minutes; reaction temperature, 40 °C; amount of immobilized lipase, 15 % w/w of total substrate and shaking speed 200 rpm. Comparison between these two ester showed that the chain length give an effect to optimize the reaction condition in esterification reaction.


2020 ◽  
Vol 17 (6) ◽  
pp. 438-442
Author(s):  
Xiaofang Ma ◽  
Shunxi Li ◽  
Samrat Devaramani ◽  
Guohu Zhao ◽  
Daqian Xu

The elimination of volatile organic solvents in organic synthesis is the most important goal in “Green” chemistry. We report a simple, efficient and facile method for the addition of progargyl bromide to carbonyl compounds using Mg metal as a mediator under solvent-free conditions which could regioselectively generate homopropargyl alcohols efficiently in good to excellent yields. The procedure has advantages such as short reaction time, operationally simple, excellent product yields, high regioselectivity and organic solvent-free.


2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Hsiao-Ching Chen ◽  
Hen-Yi Ju ◽  
Tsung-Ta Wu ◽  
Yung-Chuan Liu ◽  
Chih-Chen Lee ◽  
...  

An optimal continuous production of biodiesel by methanolysis of soybean oil in a packed-bed reactor was developed using immobilized lipase (Novozym 435) as a catalyst in atert-butanol solvent system. Response surface methodology (RSM) and Box-Behnken design were employed to evaluate the effects of reaction temperature, flow rate, and substrate molar ratio on the molar conversion of biodiesel. The results showed that flow rate and temperature have significant effects on the percentage of molar conversion. On the basis of ridge max analysis, the optimum conditions were as follows: flow rate 0.1 mL/min, temperature52.1∘C, and substrate molar ratio 1 : 4. The predicted and experimental values of molar conversion were83.31±2.07% and82.81±.98%, respectively. Furthermore, the continuous process over 30 days showed no appreciable decrease in the molar conversion. The paper demonstrates the applicability of using immobilized lipase and a packed-bed reactor for continuous biodiesel synthesis.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Xiao-chuan Jia ◽  
Jing Li ◽  
Yu Ding ◽  
Bin Zhang ◽  
Na Wang ◽  
...  

A robust, facile, and solvent-free route for the three-component synthesis of 2H-indazolo[2,1-b]phthalazine-triones in the presence of a catalytic amount ofp-toluene sulfonic acid utilizing grinding has been developed. Short reaction time, simple operation, and high yields are the advantages of this protocol.


Fuel ◽  
2010 ◽  
Vol 89 (12) ◽  
pp. 3960-3965 ◽  
Author(s):  
Liping Zhang ◽  
Shuzhen Sun ◽  
Zhong Xin ◽  
Boyang Sheng ◽  
Qun Liu

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1357
Author(s):  
Ronaldo Rodrigues de Sousa ◽  
Ayla Sant’Ana da Silva ◽  
Roberto Fernandez-Lafuente ◽  
Viridiana Santana Ferreira-Leitão

The adoption of biocatalysis in solvent-free systems is an alternative to establish a greener esters production. An interesting correlation between the acid:alcohol molar ratio and biocatalyst (immobilized lipase) loading in the optimization of ester syntheses in solvent-free systems had been observed and explored. A simple mathematical tool named Substrate-Enzyme Relation (SER) has been developed, indicating a range of reaction conditions that resulted in high conversions. Here, SER utility has been validated using data from the literature and experimental assays, totalizing 39 different examples of solvent-free enzymatic esterifications. We found a good correlation between the SER trends and reaction conditions that promoted high conversions on the syntheses of short, mid, or long-chain esters. Moreover, the predictions obtained with SER are coherent with thermodynamic and kinetics aspects of enzymatic esterification in solvent-free systems. SER is an easy-to-handle tool to predict the reaction behavior, allowing obtaining optimum reaction conditions with a reduced number of experiments, including the adoption of reduced biocatalysts loadings.


Catalysts ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 338 ◽  
Author(s):  
Shang-Ming Huang ◽  
Ping-Yu Wu ◽  
Jiann-Hwa Chen ◽  
Chia-Hung Kuo ◽  
Chwen-Jen Shieh

Ferulic acid esters have been suggested as a group of natural chemicals that have the function of sunscreen. The study aimed to utilize an environmentally-friendly enzymatic method through the esterification of ferulic acid with octanol, producing octyl ferulate. The Box-Behnken experimental design for response surface methodology (RSM) was performed to determine the synthesis effects of variables, including enzyme amount (1000–2000 propyl laurate units (PLU)), reaction temperature (70–90 °C), and stir speed (50–150 rpm) on the molar conversion of octyl ferulate. According to the joint test, both the enzyme amount and reaction temperature had great impacts on the molar conversion. An RSM-developed second-order polynomial equation further showed a data-fitting ability. Using ridge max analysis, the optimal parameters of the biocatalyzed reaction were: 72 h reaction time, 92.2 °C reaction temperature, 1831 PLU enzyme amount, and 92.4 rpm stir speed, respectively. Finally, the molar conversion of octyl ferulate under optimum conditions was verified to be 93.2 ± 1.5%. In conclusion, it has been suggested that a high yield of octyl ferulate should be synthesized under elevated temperature conditions with a commercial immobilized lipase. Our findings could broaden the utilization of the lipase and provide a biocatalytic approach, instead of the chemical method, for ferulic acid ester synthesis.


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