The simultaneous esterification and transesterification of Jatropha curcas oil (JCO) was carried out in the presence of Bi2O3 (1–7 wt.%) modified La2O3 catalyst at atmospheric pressure. The catalyst were characterized by X-ray diffraction (XRD), BET surface area, desorption of CO2 (TPD-CO2) and NH3 (TPD-NH3). Under the optimal reaction condition of methanol/oil molar ratio of 15:1, 2 wt.% of ca...

Today one of the most interesting ways to produce biodiesel is based on use oleaginous microorganisms, which can accumulate microbial oil with a composition similar vegetable oils. In this paper, we present thermo-chemical numerical model yeast production process, considering cardoon stalks as raw material. The simulation performed subdividing process into following sections: steam explosion pr...

This review highlights the biosynthesis of heterocycles in polyketide natural products with a focus on oxygen and nitrogen-containing heterocycles with ring sizes between 3 and 6 atoms. Heterocycles are abundant structural elements of natural products from all classes and they often contribute significantly to their biological activity. Progress in recent years has led to a much better understa...

This is a compilation of reference materials suggested for scientists considering a laboratory reference collection in clinical chemistry, or for librarians seeking to develop or add to an up-t-o-date library collection. Nine areas are represented: general clinical chemistry; analytical methods, procedures, and techniques; calculations and statistics; the clinical laboratory; drugs and metaboli...

Molecular Enzymology Group Colloquium Organized by D. Fell (School of Biological and Molecular Sciences, Oxford Brooke University) and D. Kell (Department of Biological Sciences, University College, Wales, Aberystwyth), Edited by D. Fell and Sponsored by Xenova Ltd, Zeneca Bioproducts, Glaxo Research and Development Ltd and SmithKline Beecham Pharmaceuticals. 653rd Meeting held at the Universit...

Accurate, economical and high-throughput gene and genome synthesis is essential to the development of synthetic biology and biotechnology. New large-scale gene synthesis methods harnessing the power of DNA microchips have recently been demonstrated. Yet, the technology is still compromised by a high occurrence of errors in the synthesized products. These errors still require substantial effort ...

Introd u ction Clinical chemistry, for decades restricted to a limited number of chemical tests, has, in recent years, through an increasing awareness of the value of the laboratory investigation of disease, and the introduc­ tion of automation and sophisticated instru­ mentation, expanded its field of operations to include a bewildering variety of tests. Advances in biochemical knowledge have ...

A novel and convenient strategy to separate, recover and reuse N-heterocyclic carbene catalysts in transesterification reactions has been developed.

Pharmaceutical preparations usually contain preservatives and sweeteners. When parabens are used as preservatives and a polyol as a sweetener, a transesterification reaction may happen, yielding the transester polyol-paraben. The products formed in the transesterification reaction of methylparaben and sorbitol were analyzed by micellar electrokinetic chromatography and by HPLC. Up to six positi...