This work aims to produce triacylglycerols (TAG) containing a medium-chain fatty acid (M) at positions sn-1,3 and a long-chain fatty acid (L) at sn-2 position, i.e. TAG of MLM type, by acidolysis of virgin olive oil with caprylic (C8:0) or capric (C10:0) acids, catalyzed by 1,3-selective Rhizopus oryzae heterologous lipase (rROL) immobilized in Eupergit® C and modified sepiolite. This lipase was produced by the methylotrophic yeast Pichia pastoris. Reactions were performed at 25 and 40 °C, for 24 h, either in solvent-free or in n-hexane media, at a molar ratio 1:2 (olive oil:free fatty acid). Higher incorporations of C8:0 (21.6 mol%) and C10:0 (34.8 mol%) into the TAG were attained in solvent-free media, at 40 °C, when rROL immobilized in Eupergit® C was used. In organic media, at 40 °C, only 15.9 and 14.1 mol%, incorporation of C8:0 or C10:0 were, respectively observed. Lower incorporations were attained for both acids (3.4-7.0 mol%) when native ROL (nROL) in both supports and rROL in modified sepiolite were used. rROL in Eupergit® C maintained its activity during the first four or three 23-h batches, respectively when C8:0 (half-life time, t 1/2 = 159 h) or C10:0 (t 1/2 = 136 h) were used, decreasing thereafter following a time delay model. © 2010 AOCS.
|Journal||JAOCS, Journal of the American Oil Chemists' Society|
|Publication status||Published - 1 Apr 2011|
- Capric acid
- Caprylic acid
- Olive oil
- Rhizopus oryzae lipase
- Structured lipids