Synthesis of structured lipids containing behenic acid from fully hydrogenated Crambe abyssinica oil by enzymatic interesterification.

Low-calorie structured lipids (SLs) rich in behenic and oleic acids were produced by enzymatic (EI) and chemical interesterification (CI) of high oleic sunflower oil and fully hydrogenated Crambe abyssinica oil in proportions of 60:40, 50:50, 40:60 and 30:70 (w/w), respectively. The immobilized lipase from Thermomyces lanuginosus (Lipozyme TL IM) was used for 3 h at 70 °C at a dosage of 7% (w/w) free of organic solvents. The original blend (BE) and the reaction products were evaluated for their fatty acid (FA) and triacylglycerols (TAG) compositions, solid fat contents, thermal analysis, regiospecific distribution of the FA, microstructure and polymorphism. The tendency was towards a reduction in the C52, C54, C60, C62 and C64 TAG contents and an increase in the C56, C58 e C66 TAG contents, therefore the solid fat content was reduced. There was lower acyl migration at the sn-2 position of the TAGs in EI as compared to CI in all the blends ratios. Needle-like crystals were predominant in the IE while large symmetrical spherulites were observed in the BE. Reduction in the mean crystal diameter was observed in all the blends, in addition to modifications of the crystal morphology. X-ray diffraction analysis showed a predominance of the ß' form crystals in both the IE and CI. The SLs were produced for application in the food industry as bakery/confectionery fats in the proportions of 60:40/50:50 and as additive in the crystallization of lipids in the proportions of 40:60/30:70.

Comparison of the regiospecific distribution from triacylglycerols after chemical and enzymatic interesterification of high oleic sunflower oil and fully hydrogenated high oleic sunflower oil blend by carbon-13 nuclear magnetic resonance.

The nutritional and organoleptic attributes of oils can proceed via interesterification of oils blends catalyzed by enzymes or chemicals. Enzymatic interesterification processes are preferred due the regiospecific outcome. Traditionally, monitoring of distribution of fatty acids (FA) in glycerol backbone is performed by enzymatic and chromatographic methods that are time-consuming, involving a series of chemical manipulations employing large volumes of organic solvents. Alternatively, carbon-13 nuclear magnetic resonance ((13)C NMR) is a fast and reliable technique that could be applied to determine the saturated and unsaturated FA distribution of the triacylglycerols (TAGs) present in high oleic sunflower oil (SO) and fully hydrogenated high oleic sunflower oil (HSO) blends and their interesterification products. The enzymatic interesterification was conducted employing the immobilized lipase from Thermomyces lanuginosus (Lipozyme TL IM), the results show that the process was not completely regiospecific at sn-1,3 positions, due to the spontaneous acyl migration from position sn-2 to sn-1,3.

Oil wastes as unconventional substrates for rhamnolipid biosurfactant production by Pseudomonas aeruginosa LBI.

Oil wastes were evaluated as alternative low-cost substrates for the production of rhamnolipids by Pseudomonas aeruginosa LBI strain. Wastes obtained from soybean, cottonseed, babassu, palm, and corn oil refinery were tested. The soybean soapstock waste was the best substrate, generating 11.7 g/L of rhamnolipids with a surface tension of 26.9 mN/m, a critical micelle concentration of 51.5 mg/L, and a production yield of 75%. The monorhamnolipid RhaC(10)C(10) predominates when P. aeruginosa LBI was cultivated on hydrophobic substrates, whereas hydrophilic carbon sources form the dirhamnolipid Rha(2)C(10)C(10) predominantly.