Browsing by Subject "Biosynthesis"
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- PublicationOpen AccessENZYMATIC BIOSYNTHESIS OF RICINOLEIC ACID ESTOLIDES(Elsevier, 2005-05-31) Bódalo-Santoyo, A.; Bastida Rodríguez, Josefa; Máximo Martín, María Fuensanta; Montiel Morte, María Claudia; Murcia Almagro, María Dolores; Ingeniería QuímicaCandida rugosa lipase has been shown to have sufficient activity to catalyse the enzymatic synthesis of ricinoleic acid estolides in a batch reactor. The water requirements of the reactor change during the reaction: at the beginning of the process a minimum amount of water is necessary but, later, the reaction mixture must be dried out to obtain an estolide with a high degree of condensation. The influence on the reaction rate of variables, such as water content, enzyme concentration and mixing devices, was established and optimised. Using an initial water content of 144000 ppm and a lipase concentration of 13.33 mgE/g ricin, and maintaining the temperature at 40°C by mean of hot air circulation and using a three-bladed propeller stirrer as mixing device, an estolide of ricinoleic acid with an acid number of 65 was obtained in 48 hours.
- PublicationOpen AccessMolecular and cellular aspects and regulation of intestinal lactase-phlorizin hydrolase(Murcia : F. Hernández, 2001) Naim, H.Y.Carbohydrates are hydrolyzed in the intestinal lumen by specific enzymes to monosaccharides before transport across the brush border membrane of epithelial cells into the cell interior. The enzymes implicated in the digestion of carbohydrates in the intestinal lumen are membrane-bound glycoproteins that are expressed at the apical domain of the enterocytes. Absent or reduced activity of one of these enzymes is the cause of disaccharide intolerance and malabsorption, the symptoms of which are abdominal pain, cramps or distention, flatulence, nausea and osmotic diarrhea. Lactose intolerance is the most common intestinal disorder that is associated with an absence or drastically reduced levels of an intestinal enzyme, in this case lactase-phlorizin hydrolase (LPH). The pattern of reduction of activity has been temed late onset of lactase deficiency or adult type hypolactasia. It was thought that the regulation of LPH was posttranslational and was associated with altered structural features of the enzyme. Recent studies, however, suggest that the major mechanism of regulation of LPH is transcriptional. Other forms of lactose intolerance include the rare congenital lactase deficiency and secondary forms, such as those caused by mucosa1 injury, due to infectious gastroenteritis, celiac disease, parasitic infection, drug-induced enteritis and Crohn's disease. This review will shed light on important strucural and biosynthetic aspects of LPH, the role played by particular regions of the LPH protein in its transport, polarized sorting, and function, as well as on the gene expession and regulation of the activity of the enzyme.
- PublicationOpen AccessSCREENING AND SELECTION OF LIPASES FOR THE ENZYMATIC PRODUCTION OF POLYGLYCEROL POLYRICINOLEATE(2009-05-07) Bódalo, A.; Bastida Rodríguez, Josefa; Máximo Martín, María Fuensanta; Montiel Morte, María Claudia; Gómez, M.; Ortega Requena, Salvadora; Ingeniería QuímicaWe have demonstrated, for the first time, that polyglylcerol polyricinoleate (PGPR) can be synthesised using lipases as biocatalyst with very good results. Of the twenty one lipases screened for their ability to catalyse PGPR production from a mixture of polyricinoleic acid and polyglycerol-3, only twelve lipases were able to catalyse the reaction. All of them were from microbial sources (bacteria and fungi) and were 1, 3-specific or "random" lipases. The selection procedure was based not only on the enzymatic activity but also on economic criteria. Lipases from Mucor javanicus, Rhizopus arrhizus and Rhizopus oryzae were finally chosen, and all three enzymes were successfully immobilized by adsorption onto an anion exchange resin where they showed their suitability to catalyse the synthesis of PGPR. This represents a promising starting point for developing an industrial process for the green production of polyglycerol polyricinoleate.
- PublicationOpen AccessSolvent-free polyglycerol polyricinoleate synthesis mediated by lipase from Rhizopus arrhizus(2011-02-04) Gómez, J.L.; Bastida Rodríguez, Josefa; Máximo Martín, María Fuensanta; Montiel Morte, María Claudia; Murcia Almagro, María Dolores; Ortega Requena, Salvadora; Ingeniería Química