Descripción: Lipases from different sources catalyze the polyesterification of glycerol and several dicarboxylic acids in presence or organic solvents.

Descripción: A series of acyl esters of 3,17-β-estradiol has been prepared by an enzymatic methodology. Eleven 17-monoacyl products (five novel compounds) were obtained in a highly regioselective way by acylation of 3,17-β-estradiol or by alcoholysis of the corresponding diacyl derivatives. The influence of various reaction parameters such as molar ratio, enzyme:substrate ratio and temperature was evaluated. Among the tested lipases, Candida rugosa lipase appeared to be the most appropriate in monoacylation and lipase from Candida antarctica in alcoholysis. The advantages presented by this methodology such as mild reaction conditions, economy and low environmental impact, make the biocatalysis a convenient way to prepare monoacyl derivatives of 3,17-β-estradiol containing the aromatic 3-hydroxyl group free. Some of these compounds are recongnized as useful products in the pharmaceutical industry. ©ARKAT.

Descripción: The yeast Yarrowia lipolytica accumulates oils and is able to produce extracellular lipases when growing in different carbon sources including glycerol, the principal by-product of the biodiesel industry. In this study, biomass production of a novel mutant strain of Y. lipolytica was statistically optimized by Response Surface Methodology in media containing biodiesel-derived glycerol as main carbon source. This strain exhibited distinctive morphological and fatty acid profile characteristics, and showed an increased extracellular lipase activity. An organic source of nitrogen and the addition of 1.0 g/l olive oil were necessary for significant lipase production. Plackett-Burman and Central Composite Statistical Designs were employed for screening and optimization of fermentation in shaken flasks cultures, and the maximum values obtained were 16.1 g/l for biomass and 12.2 Units/ml for lipase, respectively. Optimized batch bioprocess was thereafter scaled in aerated bioreactors and the values reached for lipase specific activity after 95 % of the glycerol had been consumed, were three-fold higher than those obtained in shaken flasks cultures. A sustainable bioprocess to obtain biomass and extracellular lipase activity was attained by maximizing the use of the by-products of biodiesel industry.