scholarly journals Novozym® 435 and Lipozyme® RM IM as Biocatalysts for Benzyl Benzoate Synthesis

2021 ◽  
Vol 12 (6) ◽  
pp. 8271-8284
Keyword(s):  
Industrial Sector ◽  
Enzyme Concentration ◽  
Chemical Processes ◽  
Molar Ratio ◽  
Benzyl Benzoate ◽  
Immobilized Lipases ◽  
Benzoic Anhydride ◽  
Maximum Conversion ◽  
Increasing Demand ◽  
Full Factorial

With the ever-increasing demand for clean technology in the industrial sector, natural methods, such as enzyme-catalyzed, represent a sustainable alternative to industrial chemical processes. In this context, the synthesis of benzyl benzoate ester using commercial immobilized lipases was evaluated. For this, a kinetic study was carried out to determine the reaction time (24 h) and enzyme concentration (10 wt%). Then, a 22 full factorial design was proposed to evaluate the effect of molar ratio (benzyl alcohol to benzoic anhydride) and temperature on conversion of benzyl benzoate in the presence of tert-butanol as solvent. For the Novozym® 435, maximum conversion (32%) was achieved at 60 ºC, using a molar ratio of 1:5 (alcohol to anhydride). A maximum conversion of 51% was obtained for Lipozyme® RM IM at 40 ºC and the molar ratio of 1:5. The benzyl benzoate showed moderate antimicrobial action against S. aureus (MIC = 0.05 mg μL-1). With the results, the conclusion was that the methodology of design of experiments was adequate for the proposed system and allowed the optimization of the production of benzyl benzoate.

scholarly journals Novel and Efficient Synthesis of Phenethyl Formate via Enzymatic Esterification of Formic Acid

Biomolecules ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 70 ◽  
Author(s):  
Minguk Shin ◽  
Jeongbae Seo ◽  
Yesol Baek ◽  
Taek Lee ◽  
Min Jang ◽  
...  
Keyword(s):  
Formic Acid ◽  
Enzymatic Synthesis ◽  
Value Added ◽  
Enzyme Concentration ◽  
Molar Ratio ◽  
Enzymatic Esterification ◽  
Efficient Synthesis ◽  
Conversion Yield ◽  
Synthesis Conditions ◽  
Immobilized Lipases

Current methods for the production of esters, including chemical synthesis and extraction from natural sources, are hindered by low yields and environmental pollution. The enzymatic synthesis of these compounds could help overcome these problems. In this study, phenethyl formate, a commercially valuable formate ester, was synthesized using commercial immobilized lipases. The effects of specific enzymes, enzyme concentration, formic acid:phenethyl alcohol molar ratio, temperature, and solvent were studied in order to optimize the synthesis conditions, which were identified as 15 g/L of Novozym 435 enzyme, a 1:5 formic acid:phenethyl alcohol molar ratio, a 40 °C reaction temperature, and 1,2-dichloroethane as the solvent. Under these conditions, phenethyl formate was obtained in a conversion yield of 95.92%. In addition, when 1,2-dichloroethane was replaced with toluene as the solvent, the enzyme could be recycled for at least 20 reactions with a steady conversion yield above 92%, testifying to the economic aspects of the process. The enzymatic synthesis of phenethyl formate using the proposed method is more environmentally friendly than methods currently employed in academic and laboratory settings. Moreover, the method has the potential to enhance the value-added properties of formic acid owing to its downstream use in the production of commercially essential esters.

scholarly journals Current perspective on production and applications of microbial cellulases: a review

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Nisha Bhardwaj ◽  
Bikash Kumar ◽  
Komal Agrawal ◽  
Pradeep Verma
Keyword(s):  
Critical Factor ◽  
Industrial Sector ◽  
Industrial Applications ◽  
Cellulolytic Enzymes ◽  
Promising Tool ◽  
The Status ◽  
Key Enzyme ◽  
Increasing Demand ◽  
Immobilization Techniques ◽  
Insight Into

AbstractThe potential of cellulolytic enzymes has been widely studied and explored for bioconversion processes and plays a key role in various industrial applications. Cellulase, a key enzyme for cellulose-rich waste feedstock-based biorefinery, has increasing demand in various industries, e.g., paper and pulp, juice clarification, etc. Also, there has been constant progress in developing new strategies to enhance its production, such as the application of waste feedstock as the substrate for the production of individual or enzyme cocktails, process parameters control, and genetic manipulations for enzyme production with enhanced yield, efficiency, and specificity. Further, an insight into immobilization techniques has also been presented for improved reusability of cellulase, a critical factor that controls the cost of the enzyme at an industrial scale. In addition, the review also gives an insight into the status of the significant application of cellulase in the industrial sector, with its techno-economic analysis for future applications. The present review gives a complete overview of current perspectives on the production of microbial cellulases as a promising tool to develop a sustainable and greener concept for industrial applications.

Readiness in Systems Implementation

2011 ◽  
pp. 15-51
Author(s):  
Eric Lou ◽  
Hafez Salleh
Keyword(s):  
Higher Education ◽  
International Students ◽  
Industrial Sector ◽  
Business Law ◽  
Systems Implementation ◽  
Education Organization ◽  
Health Related ◽  
Student Information ◽  
Increasing Demand

Higher education sector is notorious for lagging behind the industrial sector in the application of IT/IS systems and infrastructure. This chapter presents the application of the IT/IS readiness model in a higher education organization. This organisation was established in 1967 and currently has about 2,500 staff and 18,000 students, of which, 3,000 are international students from all over the world. The organization comprises of 14 schools and 13 research institutes and offers programmes various fields, which include virtual reality, magnetic and optics, business, law, genetic algorithms, health-related studies, and building construction. In 1996, Academic Division (AD) identified the need to improve the management of the student database due to the increase of students and programs offered by the organization. AD also identified that the Legacy Student Information System (SIS) was unable to cope with the increasing demand of data administration. This case study presents the overview of issues encountered while assessing the e-readiness of the organisation after most of the systems went live. Post implementation, the system has been able to reduce the redundancies in processes and has been able to provide a more effective support to students and staff. However, still there are several issues and conflicts that need to be resolved, and a radical rethink of the processes supporting the IT system is needed to achieve any further efficiency.

Influence of salts on Michaelis-constant values for NADH.

1977 ◽  
Vol 23 (12) ◽  
pp. 2231-2237 ◽  
Author(s):  
B F Howell ◽  
S McCune ◽  
R Schaffer
Keyword(s):  
Lactate Dehydrogenase ◽  
Sodium Phosphate ◽  
Enzyme Inhibitor ◽  
Enzyme Concentration ◽  
Molar Ratio ◽  
Inhibitory Influence ◽  
Michaelis Constant ◽  
Constant Attention ◽  
Enzymatic Assays ◽  
First Order

Abstract We previously observed [Clin. Chem. 22, 1648 (1976)] that values of the Michaelis constant for NADH for the conversion of pyruvate to lactate with lactate dehydrogenase (EC 1.1.1.27) in the presence of 0.1 mol/liter buffers at 25 degrees C showed first-order dependence on enzyme concentration. This is now recognized to be the result of an inhibitory influence exerted by buffers [NH4HCO2, tris(hydroxymethyl)aminomethane, and phosphate] and salts [(NH4)2SO4 and NaCl] present in the reaction mixtures. Inhibition constants for the enzyme/inhibitor complexes formed with these substances are about 0.3 mol/liter for competition of NH4HCO3 with NaOH and 0.4 mol/liter for competition of NH4HCO3 with pyruvate; they are 0.6 mol/liter for NaCl, 1.0 mol/liter for sodium phosphate, 0.3 mol/liter for (NH4)2SO4, and 0.8 mol/liter for tris(hydroxymethyl)aminomethane when these substances compete with NADH. Because of the large molar ratio of buffer to substrate (about 10(9):1) in enzymatic assays, the buffer concentration significantly influences the Michaelis constant, despite the large value for the inhibition constant. Attention to the concentrations of these substances may be required for decreasing variability in clinical assays in which lactate dehydrogenase and possible other enzymes are used.

scholarly journals Alumina Extraction from Coal Fly Ash via Low-Temperature Potassium Bisulfate Calcination

Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 585 ◽  
Author(s):  
Chunbin Guo ◽  
Jingjing Zou ◽  
Shuhua Ma ◽  
Jianlin Yang ◽  
Kehan Wang
Keyword(s):  
Fly Ash ◽  
Low Temperature ◽  
Extraction Efficiency ◽  
Coal Fly Ash ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Increasing Demand ◽  
Technology Effects ◽  
Best Fit

Owing to the depletion of bauxite and increasing demand for alumina, calcination methods for extracting alumina from coal fly ash (CFA) were developed. However, these methods have disadvantages such as the need for high temperatures and the emission of toxic gases. Hence, in this study, Al2O3 was extracted from CFA via low-temperature potassium bisulfate calcination technology. Effects of the potassium bisulfate amount, calcination temperature, and calcination time on the alumina extraction efficiency were investigated using X-ray diffraction, thermal gravimetry, scanning electron microscopy, differential scanning calorimetry, and energy-dispersive spectroscopy. It was found that this technique could recover alumina efficiently, and potassium bisulfate significantly contributed to the degradation of mullite and corundum phases. Al2O3 in CFA was converted into soluble K3Al(SO4)3. With a KHSO4/Al2O3 molar ratio of 7:1, calcining temperature of 230 °C, and calcining time of 3 h, the alumina extraction efficiency reached a maximum of 92.8%. The Avrami–Erofeev equation showed the best fit with the kinetic data for the low-temperature calcination of CFA with KHSO4. The activation energy was 28.36 kJ/mol.

Studies on the Immobilized-Lipase-Catalyzed Esterification of Alkyl Oleates in Solvent-Free Systems

2013 ◽  
Vol 645 ◽  
pp. 19-23 ◽  
Author(s):  
Hui Zhong ◽  
Zheng Fang ◽  
Bao Hua Zou ◽  
Xin Li ◽  
Kai Guo
Keyword(s):  
Oleic Acid ◽  
Low Temperature ◽  
High Selectivity ◽  
Immobilized Lipase ◽  
Enzyme Concentration ◽  
Molar Ratio ◽  
High Yield ◽  
Secondary Alcohols ◽  
Tertiary Alcohols ◽  
Candida Sp

The esterification of oleic acid with alkyl alcohols in solv ent-free systems was catalyzed by an immobilized lipase from Candida sp . 99-125. The influence of several factors, including enzyme concentration, temperature, molar ratio between oleic acid and alkyl alcohols, and structure of alcohol was also investigated. The results indicated that the reactions catalyzed by lipase at 20 o C, in the presence of 3% (w/w) lipase, on the molar ratio of 1:1 between oleic acid and alcohols, afforded products in high yield. It showed high selectivity to primary and low selectivity to secondary alcohols and tertiary alcohols because of the sterically hindered effect. Methanol has certain toxicity on the activity of the lipase. The lipase from Candida sp. 99-125 was identified to be an effective catalyst in the esterification of alcohol and oleic acid at low temperature.

scholarly journals Dehydrogenation of propane with CO2 – a new green process for propene and synthesis gas production

2012 ◽  
Vol 14 (4) ◽  
pp. 77-82 ◽  
Author(s):  
Piotr Michorczyk ◽  
Kamila Zeńczak ◽  
Rafał Niekurzak ◽  
Jan Ogonowski
Keyword(s):  
Synthesis Gas ◽  
Process Integration ◽  
Gas Production ◽  
Chemical Processes ◽  
Thermodynamic Calculations ◽  
Molar Ratio ◽  
Green Process

Abstract Dehydrogenation of propane in the presence of CO2 was considered as an alternative to commercial dehydrogenation pathway of obtaining propene and the new sources of synthesis gas. Based on thermodynamic calculations and a catalytic tests it was shown that by controlling CO2 concentration in the feed the molar ratio of H2/CO (synthesis gas) in the products mixture can be regulated. Several different pathways of DHP-CO2 process integration with commercialized chemical processes utilized synthesis gas were proposed

scholarly journals Statistical Optimization of Biodiesel Production from Salmon Oil via Enzymatic Transesterification: Investigation of the Effects of Various Operational Parameters

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 700
Author(s):  
Vegneshwaran V. Ramakrishnan ◽  
Deepika Dave ◽  
Yi Liu ◽  
Winny Routray ◽  
Wade Murphy
Keyword(s):  
Atlantic Salmon ◽  
Immobilized Lipase ◽  
Enzyme Concentration ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Operational Parameters ◽  
Enzymatic Transesterification ◽  
Optimum Parameters ◽  
Response Surface Modelling ◽  
The Relationship

The enzymatic transesterification of Atlantic salmon (Salmo salar) oil was carried out using Novozym 435 (immobilized lipase from Candida antartica) to produce biodiesel. A response surface modelling design was performed to investigate the relationship between biodiesel yield and several critical factors, including enzyme concentration (5, 10, or 15%), temperature (40, 45, or 50 °C), oil/alcohol molar ratio (1:3, 1:4, or 1:5) and time (8, 16, or 24 h). The results indicated that the effects of all the factors were statistically significant at p-values of 0.000 for biodiesel production. The optimum parameters for biodiesel production were determined as 10% enzyme concentration, 45 °C, 16 h, and 1:4 oil/alcohol molar ratio, leading to a biodiesel yield of 87.23%. The step-wise addition of methanol during the enzymatic transesterification further increased the biodiesel yield to 94.5%. This is the first study that focused on Atlantic salmon oil-derived biodiesel production, which creates a paradigm for valorization of Atlantic salmon by-products that would also reduce the consumption and demand of plant oils derived from crops and vegetables.

scholarly journals Factor which Affect ZSM-5 Acidity

2019 ◽  
Author(s):  
Siti Safira Nur ◽  
Tiara Mahendra Kurniawati ◽  
Syarah Habibah Balqis
Keyword(s):  
Chemical Processes ◽  
Active Part ◽  
Molar Ratio ◽  
Template Analysis ◽  
Ir Analysis

Zeolite is a crystal which have bonding with Silicone and Aluminum with pores inside the crystal and connected in a certain structure. Due to zeolites function, demand of zeolite has been increasing lately. The Acid or active part takes a lead to many chemical processes. Many methods to synthesized Zeolites and form its structure or frameworks. Zeolites’ acidity can be affected by the structure itself. Such as the amount of Si/Al molar ratio also cations that fill in the zeolite template. Analysis using IR has been used to determine the absorbance of pyridine by zeolite to determine the acidity of zeolite. Zeolite which used by IR analysis is ZSM-5.

scholarly journals Nanoreactors for green catalysis

2018 ◽  
Vol 14 ◽  
pp. 716-733 ◽  
Author(s):  
M Teresa De Martino ◽  
Loai K E A Abdelmohsen ◽  
Floris P J T Rutjes ◽  
Jan C M van Hest
Keyword(s):  
Green Chemistry ◽  
Industrial Sector ◽  
Environmental Risks ◽  
Chemical Processes ◽  
Environmentally Benign ◽  
Technological Advancement ◽  
One Pot ◽  
Polymer Vesicles ◽  
Key Drivers ◽  
Green Catalysis

Sustainable and environmentally benign production are key drivers for developments in the chemical industrial sector, as protecting our planet has become a significant element that should be considered for every industrial breakthrough or technological advancement. As a result, the concept of green chemistry has been recently defined to guide chemists towards minimizing any harmful outcome of chemical processes in either industry or research. Towards greener reactions, scientists have developed various approaches in order to decrease environmental risks while attaining chemical sustainability and elegancy. Utilizing catalytic nanoreactors for greener reactions, for facilitating multistep synthetic pathways in one-pot procedures, is imperative with far-reaching implications in the field. This review is focused on the applications of some of the most used nanoreactors in catalysis, namely: (polymer) vesicles, micelles, dendrimers and nanogels. The ability and efficiency of catalytic nanoreactors to carry out organic reactions in water, to perform cascade reaction and their ability to be recycled will be discussed.

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