In this essay, lipase from Burkholderia cepacia was immobilized into 3-glycidoxypropyltrimethoxysilane (GPTMS) and tetramethoxysilane (TMOS) derived sol-gels. GPTMS:TMOS molar ratio of 1:3 was found to yield the best result. The morphological characteristics were investigated based on SEM and BET analysis. Sample mean pore diameter was 39.1 nm, it had a specific surface area of 60 m2/g prior to...

BACKGROUND Waste animal fat is a promising feedstock to replace vegetable oil that widely used in commercial biodiesel process, however the high content of free fatty acid in waste fat makes it unfeasible to be processed with commercial base-catalytic process. Enzymatic process is preferable to convert waste fat into biodiesel since enzyme can catalyze both esterification of free fatty acid and...

The Rag1 and Rag2 proteins initiate V(D)J recombination by introducing site-specific DNA double-strand breaks. Cleavage occurs by nicking one DNA strand, followed by a one-step transesterification reaction that forms a DNA hairpin structure. A similar reaction allows Rag transposition, in which the 3'-OH groups produced by Rag cleavage are joined to target DNA. The Rag1 active site DDE triad cl...

Biodiesel is an alternative diesel fuel made from renewable biological resources. During the process of biodiesel production, lipase-catalyzed transesterification is a crucial step. However, current techniques using methanol as acyl acceptor have lower enzymatic activity; this limits the application of such techniques in large-scale biodiesel production. Furthermore, the lipid feedstock of curr...

We recently used in vitro selection to identify many deoxyribozymes that catalyze DNA phosphodiester bond hydrolysis and create 5'-phosphate and 3'-hydroxyl termini. Alternatively, numerous deoxyribozymes have been identified for catalysis of RNA cleavage by 2'-hydroxyl transesterification, forming 2',3'-cyclic phosphate and 5'-hydroxyl termini. In this study, we investigated the ability of DNA...

The influence of sonoluminescence transesterification on biodiesel physicochemical properties was investigated and the results were compared to those of traditional mechanical stirring. This study was conducted to identify the mechanistic features of ultrasonication by coupling statistical analysis of the experiments into the simulation of cavitation bubble. Different combinations of operationa...

Biodiesel is an alternative source of energy in diesel engines in its neat form or as a blend with conventional diesel fuel. The raw feedstock costs represent a lot of the overall biodiesel production cost. Therefore, the employment of waste oils or non-edible oils (which do not compete with edible oils) as feedstock for biodiesel production are presented as the best alternative. However, the p...

We identified the enzyme(s) involved in the hydrolysis of the ethyl ester prodrug CDP323 (C28H29BrN403) and characterized its transesterification in the presence of ethanol with special emphasis on the risks of drug-drug interaction. The hydrolysis of CDP323 was evaluated in vitro using human liver and intestinal microsomes and recombinant human carboxylesterases (hCES1 and 2) and was shown to ...

BACKGROUND Transesterification catalyzed by solid base catalyst is a brilliant technology for the noble process featuring the fast reaction under mild reacting condition in biodiesel production. Heterogeneous base catalysts are generally more reactive than solid acid catalysts which require extreme operating condition for high conversion and biodiesel yield. In the present study, synthesis of b...

This work addresses a reliable in situ transesterification process which integrates lipid extraction from wet microalgae, and its conversion to biodiesel, with a yield higher than 90 wt.%. This process enables single-step production of biodiesel from microalgae by mixing wet microalgal cells with solvent, methanol, and acid catalyst; and then heating them in one pot. The effects of reaction par...