Biomedical subjects

J Lema

Publications and source records attributed to J Lema.

3 recordsLinked to original sources

PubMed2004

Environmental engineering education in Spain.

There is a growing demand for engineers and technologists who show multidisciplinary expertise to deal with environmental issues. As a result of this demand, most countries are adapting their old university programs on environmental engineering education. In Spain an official environmental engineering degree does not yet exist, but the Council of Universities is working to present a proposal, based on Bologna agreement concepts. The paper summarizes not only the future perspectives of environmental engineering education in Spain, but also the evolution of the approach during the last decades, which includes the role of the private initiative, the environmental sciences degree, and the intensification in different traditional engineering degrees. Finally, the paper briefly details and compares the syllabus developed in the only four Spanish universities where environmental engineering is offered as a non-official post-graduate course lasting two years.

Curriculum↗

PubMed1999

Use of cheese whey as a substrate to produce manganese peroxidase by Bjerkandera sp BOS55.

Manganese peroxidase, MnP, is one of the major ligninolytic enzymes produced by a number of white-rot fungi. The ability of this enzyme to degrade lignin by the fungus Bjerkanderasp BOS55 has opened its application to related bioprocesses such as recalcitrant-compound degradation and effluent decolorization. The medium reported to induce MnP production is composed of chemical grade reagents, all with relatively high costs for application to detoxification purposes. The use of inexpensive sources for MnP production can bring its implementation closer. For this purpose, dairy residues from cheese processing were considered. MnP production obtained using crude whey as the sole substrate reached appreciable levels, around 190 U L-1, values comparable to those found with synthetic media (between 175-250 U L-1). Thus, this cheese-processing byproduct can be used as an inexpensive alternative for the large-scale production of MnP.

Journal Article↗

PubMed1997

Manganese Is Not Required for Biobleaching of Oxygen-Delignified Kraft Pulp by the White Rot Fungus Bjerkandera sp. Strain BOS55.

The white rot fungus Bjerkandera sp. strain BOS55 extensively delignified and bleached oxygen-delignified eucalyptus kraft pulp handsheets. Biologically mediated brightness gains of up to 14 ISO (International Standards Organization units) were obtained, providing high final brightness values of up to 80% ISO. In nitrogen-limited cultures (2.2 mM N), manganese (Mn) greatly improved manganese-dependent peroxidase (MnP) production. However, the biobleaching was not affected by the Mn nutrient regimen, ranging from 1,000 (mu)M added Mn to below the detection limit of 0.26 (mu)M Mn in EDTA-extracted pulp medium. The lowest Mn concentration tested was at least several orders of magnitude lower than the K(infm) known for MnP. Consequently, it was concluded that Mn is not required for biobleaching in Bjerkandera sp. strain BOS55. Nonetheless, fast protein liquid chromatography profiles indicated that MnP was the predominant oxidative enzyme produced even under culture conditions in the near absence of manganese. High nitrogen (22 mM N) and exogenous veratryl alcohol (2 mM) repressed biobleaching in Mn-deficient but not in Mn-sufficient culture medium. No correlation was observed between the titers of extracellular peroxidases and the biobleaching. However, the decolorization rate of the polyaromatic dye Poly R-478 was moderately correlated to the biobleaching under a wide range of Mn and N nutrient regimens.

Journal Article↗