The hairpin ribozyme is an example of a small catalytic RNA which catalyses the endonucleolytic transesterification of RNA in a highly sequence-specific manner. The hairpin ribozyme, in common with all other small ribozymes such as the hammerhead, requires the presence of a divalent metal ion co-factor (typically magnesium) for the reaction to take place. To investigate the role of magnesium io...

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.

Biodiesel research has been carried out via transesterification. However, biodiesel products (methyl esters) have not encountered new insights, because feedstocks explored and studied. Various optimum conditions on transesterification reaction could produce different methyl ester type with compound. So, this review describes various oil feedstock that were to find insights about type. The took ...