Glucuronoyl esterases are enzymes involved in microbial plant cell-wall degradation. In this study we purified and characterized two recombinant Phanerochaete chrysosporium glucuronoyl esterases, PcGE1 and PcGE2. The catalytic activity of these and previously described glucuronoyl esterases was investigated on new synthetic substrates, methyl esters of uronic acids and their glycosides, prepare...

Enantioselective reduction of the carbonyl group of three phenylglyoxylic acid esters (methyl, ethyl, and n-propyl esters, 2-4) was conducted using blended plant materials (roots of carrot, beetroot, celeriac and parsley; apple). All used biocatalysts transformed these esters to the corresponding mandelic acid esters with high yield, preferably into the respective R-enantiomer. Butanedione addi...

In this study, the non-catalytic supercritical method has been studied in utilizing dimethyl carbonate. It was demonstrated that, the supercritical dimethyl carbonate process without any catalysts applied, converted triglycerides to fatty acid methyl esters with glycerol carbonate and citramalic acid as by-products, while free fatty acids were converted to fatty acid methyl esters with glyoxal....

In this study, Jatropha curcas oil was used as feedstock for biodiesel production by alkali-catalyzed methanolysis. To establish the optimum conditions for biodiesel production, effects of certain factors were investigated, these factors are oil-to-methanol molar ratios (1:4 1:8), KOH catalyst concentrations (0.5 1.5% w/w oil), reaction temperatures (50 70oC), and reaction times (55 90minutes)....

Biodiesel, defined as the monoalkyl esters of vegetable oils and animal fats, is an alternative to conventional petroleum-based diesel fuel. Biodiesel has been prepared from numerous common vegetable oils or fats as well as new or less common feedstocks. Major issues facing biodiesel include several technical aspects such as cold flow and oxidative stability as well as availability of sufficien...

A partially purified preparation of an alpha-amino acid ester hydrolase was obtained from Acetobacter turbidans A.T.C.C. 9325, which catalyses synthesis of 7-(d-alpha-amino-alpha-phenylacetamido)-3-cephem-3-methyl-4- carboxylic acid (cephalexin) from methyl d-alpha-aminophenylacetate and 7-amino-3-deacetoxycephalosporanic acid. The enzyme preparation catalysed both cephalosprin synthesis from 7...

To provide information upon the ways in which Lemna paucicostata uses the methyl group of methionine, plants were grown for various periods (from 1 minute to 6.8 days) in the presence of a tracer dose of radioactive methyl-labeled methionine. Protein methionine accounted for approximately 19% of the accumulated methyl moieties; other methylated products, about 81%. The latter group included (pe...

Fatty acid methyl esters, which are used as biodiesel, can be produced by esterification of fatty acids in supercritical methanol. However, a reverse reaction, esters hydrolyzed to regenerate due the presence water, is making it difficult reduce content sufficiently. In this study, oleic was treated methanol at 310 °C/20 MPa with flow-type reactor adding formate improve yield ester. As result, ...

THE PROCEDURE of Stoffel, Chu, and Ahrens (1) for preparing and separating the methyl esters of fatty acids and the dimethylacetals (DMA) when applied to brain lipid extracts proved adequate for the nonoxygenated fatty acids and DMA. Some of the cholesterol in the extract, however, was converted to derivatives, one of which, A3kholestadiene (2), sublimed along with the methyl esters and the DMA...