Enzymatic transesterification of soybean oil with methanol and ethanol was studied. Of the nine lipases that were tested in the initial screening, lipase PS from Pseudomonas cepacia resulted in the highest yield of alkyl esters. Lipase from Pseudomonas cepacia was further investigated in immobilized form within a chemically inert, hydrophobic sol-gel support. The gel-entrapped lipase was prepar...

Kanemite was readily prepared and used as solid base catalyst for transesterification of sunflower oil to fatty acid methyl ester (FAME). The catalyst was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), N2 adsorption-desorption and field emission scanning electron microscopy (FESEM) techniques. Central Composite Design (CCD) coupled with Response Surfac...

The nrdB gene of bacteriophage T4 contains a group IA2 intron. We have investigated the kinetics of self-splicing by a shortened variant of nrdB pre-mRNA in the presence of the co-substrates guanosine and 2'-amino-2'-deoxyguanosine. The pH dependence of the first transesterification step displayed parallel linear correlations for the two different co-substrates up to pH 7, above which the react...

Diphenyl carbonate (DPC) is a precursor in the production of polycarbonate, an important engineering thermoplastic with excellent mechanical and optical properties as well as electrical and heat resistance properties. Traditionally, DPC is synthesized by the transesterification reaction of dimethyl carbonate (DMC) and phenol. In the study, phenyl acetate is used instead of phenol to react with ...

Enzymatic transesterification of soybean oil with methanol and ethanol was studied. 0f the nine lipases that were tested in the initial screening. lipase PS from Pseudornonas cepacia resulted in the highest yield of alkyl esters. Lipase from Pseudornonas cepacia was further investigated in immobilized from with in chemically inert, hydrophobic sol-gel support. The gel-entrapped lipase was prepa...

The present work studies biofuel production using an American native species that belongs to the Argemone genus. It is considered a weed, and its presence extends from southern United States some areas of South America; pleiacantha, together with other same genus, known as “chicalote”. Oil physical chemical properties confirm chicalote oil effective raw material for production, presenting fatty...

The tripeptide Z-GlyPheLeuNH2 was continuously synthesized in a high yield from three amino acid derivatives, Z-Gly, PheOMe, and LeuNH2, by immobilized thermolysin (IMT) and immobilized alpha-chymotrypsin (IMC) in an organic solvent, ethyl acetate. The optimal conditions for the synthesis of Z-GlyPheOMe were established theoretically. The yield of Z-GlyPheOMe with IMT in ethyl acetate saturated...

Static mixers, devices used for mixing immiscible liquids in a compact configuration, were found to be effective in carrying out initial transesterification reactions of canola oil and methanol. The objective of this study was to explore the possibilities of using static mixers as a continuous-flow reactor for biodiesel production. Biodiesel (canola methyl ester) was produced under varying cond...

The aim of this study was to increase the yield of biodiesel produced by Scenedesmus sp. through in situ transesterification by optimizing various process parameters. Based on the orthogonal matrix analysis for the acidic catalyst, the effects of the factors decreased in the order of reaction temperature (47.5%) > solvent quantity (26.7%) > reaction time (17.5%) > catalyst amount (8.3%). Based ...

The synthesis of ring-contracted derivatives of erythromycin A via intramolecular transesterification under microwave irradiation of 8,9-anhydroerythromycin A 6,9-hemiketal and its derivatives is described. It was found that microwave irradiation could significantly improve the yields and shorten the reaction times under either solvent-containing (method A) or solvent-free (method B) conditions.