| 1. |
|
|
| 2. |
- Adlercreutz, Patrick, et al.
(författare)
-
Enzymatic fatty acid exchange in glycerophospholipids
- 2003
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 105:10, s. 638-645
-
Forskningsöversikt (refereegranskat)abstract
- Lipases can be used to exchange fatty acids in the sn-1 position of glycerophospholipids and phospholipase A2 is useful for the corresponding exchange reaction in the sn-2 position. In both cases, the exchange can be done in a one-step acidolysis process or in a two-step process. In the latter case, the original fatty acid in the desired position is removed by enzymatic hydrolysis or alcoholysis and after isolation of the resulting lysophospholipid, the new fatty acid is introduced, using the same enzyme, in an esterification reaction. Several synthesis examples from the literature are reviewed. Incorporation of a new fatty acid into the sn-1 position is more favourable than incorporation into the sn-2 position because of the magnitudes of the equilibrium constants of the reactions and because lipases can be used at much lower water activity than phospholipase A2. With the consecutive use of both enzymes highly pure products with defined fatty acids in both positions can be obtained.
|
|
| 3. |
- Al-Hamimi, Said, et al.
(författare)
-
A Fast and Green Extraction Method for Berry Seed Lipid Extraction Using CO2 Expanded Ethanol Combined with Sonication
- 2020
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 122:4
-
Tidskriftsartikel (refereegranskat)abstract
- In this work, a combination of sonication and carbon dioxide expanded liquid extraction (SA-CXLE) is used for the first time for the extraction of lipids from berry seeds. Three solvents (ethanol, methanol and ethyl lactate) are screened for the best recoveries of total lipids. Ethanol is selected due to its efficiency, greenness and sustainability. The effects of operation variables including temperature, time and CO2 molar fraction on extraction performance are examined using a response surface methodology. The optimum conditions were found at 0.37 molar fraction of CO2 in ethanol, a temperature of 52 °C and an extraction time of 7 min for two cycles. The SA-CXLE method extracts 323 ± 38 mg g−1 seed compared to 194 ± 23 using a conventional solid-liquid extraction. SA-CXLE is successfully applied to profile lipids from gooseberry, blackcurrant, chokeberry, red currant, and rowanberry seeds. More than 17 lipid classes are characterized and identified. Gooseberry shows the highest amount of oil of 352 mg g−1 seed. Practical Applications: The developed method provides a fast, efficient and simple approach to extract and profile lipids using a combination of green solvents. Total lipid content and fatty acids composition of the berry seeds are essential information in pharmaceutical, cosmetic, food and nutritional applications.
|
|
| 4. |
- Andersson, David, et al.
(författare)
-
Ursolic acid and other pentacyclic triterpenoids stimulate intestinal alkaline sphingomyelinase in vitro
- 2006
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 108:2, s. 103-108
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Alkaline sphingomyelinase (alk-SMase) is an enzyme that hydrolyses sphingomyelin in a bile salt-dependent manner in the gastrointestinal tract, and has been proposed as an inhibitor of colon carcinogenesis. Ursolic acid (UA) is a plant-derived pentacyclic triterpenoid that has been shown to have anti-proliferative and apoptotic effects on HT29 human colon adenocarcinoma cells, with activation of alk-SMase as an early event. The aim of this study was to study the in vitro effects of UA and its analogues on the activity of purified rat intestinal alk-SMase. Methods: Rat intestinal alk-SMase activity was determined after incubation with UA in the presence and absence of taurocholate (TC). The effect was compared with boswellic acids, another group of pentacyclic triterpenoids. Results: UA enhanced the activity of rat intestinal alk-SMase in a dose-dependent manner, without a similar effect on bacterial neutral SMase. Four types of boswellic acid also increased the enzyme activity, with the effect of acetyl-keto-beta-boswellic acid being most potent. Activation of alk-SMase by TC; at a low concentration (0.4 mM), but not at a high concentration, was enhanced by UA. Conclusions: Ursolic acid and four types of boswellic acid, all pentacyclic triterpenoids, have a stimulatory effect on the activity of intestinal alk-SMase.
|
|
| 5. |
- Borg, Saskia, et al.
(författare)
-
Lipids in Eating and Appetite Regulation - A Neuro-Cognitive Perspective
- 2017
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 119:12
-
Tidskriftsartikel (refereegranskat)abstract
- Foods high in dietary fat provide a particularly energy-rich source of nutrition. A preferred food choice in humans, their intake is thought to contribute substantially to the current obesity epidemic. Fat has recently been proposed to constitute a basic taste; yet, its diverse sensory properties in the olfactory and somatosensory domain, as well as its postingestive effects have made the exact attributes that make its consumption so appealing difficult to disentangle. Recent scientific advances have shed light on the different molecular mechanisms underlying the sensory detection of fat in the periphery, and described their relevance for perceptual experience and eating behavior. However, these different analysis levels are to date poorly integrated, both within each sensory modality, and from a multisensory perspective.
|
|
| 6. |
- Cao, Xi, et al.
(författare)
-
Acyl migration in enzymatic interesterification of triacylglycerols : Effects of lipases from Thermomyces lanuginosus and Rhizopus oryzae, support material, and water activity
- 2016
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 118:10, s. 1579-1587
-
Tidskriftsartikel (refereegranskat)abstract
- The enzymatic interesterification of a solvent-free, equimolar mixture of trilaurin and 1,3-palmitin-2-olein was studied using three immobilized lipase preparations as catalysts. Analysis of triacylglycerol (TAG) content and fatty acid (FA) distribution monitored the lipase-catalyzed interesterification in sn-1,3 positions and FA exchange in the sn-2 position caused by acyl migration. Lipase from Rhizopus oryzae immobilized on polypropylene showed high sn-1,3 regioselectivity, and minimal exchange in the sn-2 position. With lipase from Thermomyces lanuginosus on silica (Lipozyme® TL IM), completely randomized FA distribution was obtained in 24 h. T. lanuginosus lipase on polypropylene caused a moderate rate of FA exchange in the sn-2 position. Thus, the T. lanuginosus lipase and silica promoted randomization of FA distribution, whereas the R. oryzae lipase and polypropylene did not. Higher water activity promoted hydrolysis and thereby increased concentrations of partial acylglycerols, but at the same time a decrease in the acyl migration rate of these intermediates was also observed. The net result was that at a certain degree of interesterification, there was no significant effect of water activity on the degree of exchange in the sn-2 position. On the other hand, a low water activity had the major advantage of giving a high yield of TAG. Practical applications: Both the type and the position of FA affect the properties of TAG. In TAG interesterification, there are thus different requirements for regiospecificity in FA exchange, depending on which product is desired. According to our results, lipase-based catalysts can be used for TAG interesterification either to achieve unchanged FA composition in sn-2 position or fast FA randomization in all positions. This helps to broaden the application of lipases in interesterification. The production of TAG can be tailor-made for lipid mixtures with particular TAG composition and FA distribution using proper lipases, support materials, water activity, and reaction time. The enzymatic LLL–POP model reaction was used to investigate effects of lipase, support material, and water activity on acyl migration. (Fig. A): effect of Lipozyme® TL IM, TLPP and ROPP at aw 0.26, (Fig. B): effect of aw between 0.15 and 0.80 using Lipozyme® TL IM as the example.
|
|
| 7. |
- Carlsson, Anders, et al.
(författare)
-
Replacing fossil oil with fresh oil - with what and for what?
- 2011
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 113, s. 812-831
-
Forskningsöversikt (refereegranskat)abstract
- Industrial chemicals and materials are currently derived mainly from fossil-based raw materials, which are declining in availability, increasing in price and are a major source of undesirable greenhouse gas emissions. Plant oils have the potential to provide functionally equivalent, renewable and environmentally friendly replacements for these finite fossil-based raw materials, provided that their composition can be matched to end-use requirements, and that they can be produced on sufficient scale to meet current and growing industrial demands. Replacement of 40% of the fossil oil used in the chemical industry with renewable plant oils, whilst ensuring that growing demand for food oils is also met, will require a trebling of global plant oil production from current levels of around 139 MT to over 400 MT annually. Realisation of this potential will rely on application of plant biotechnology to (i) tailor plant oils to have high purity (preferably > 90%) of single desirable fatty acids, (ii) introduce unusual fatty acids that have specialty end-use functionalities and (iii) increase plant oil production capacity by increased oil content in current oil crops, and conversion of other high biomass crops into oil accumulating crops. This review outlines recent progress and future challenges in each of these areas.Practical applications: The research reviewed in this paper aims to develop metabolic engineering technologies to radically increase the yield and alter the fatty acid composition of plant oils and enable the development of new and more productive oil crops that can serve as renewable sources of industrial feedstocks currently provided by non-renewable and polluting fossil-based resources. As a result of recent and anticipated research developments we can expect to see significant enhancements in quality and productivity of oil crops over the coming decades. This should generate the technologies needed to support increasing plant oil production into the future, hopefully of sufficient magnitude to provide a major supply of renewable plant oils for the industrial economy without encroaching on the higher priority demand for food oils. Achievement of this goal will make a significant contribution to moving to a sustainable carbon-neutral industrial society with lower emissions of carbon dioxide to the atmosphere and reduced environmental impact as a result.
|
|
| 8. |
- Causevic, Ariana, et al.
(författare)
-
Effects of Lipase Immobilization Conditions and Support Materials for the Production of Structured Triacylglycerols
- 2023
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 125:2
-
Tidskriftsartikel (refereegranskat)abstract
- Structured triacylglycerols (STAG) with desired properties can be synthesized by transesterification using immobilized lipases. Herein, the effect of immobilization conditions and support material on the immobilization yield, specific activity and regioselectivity of lipases from Rhizomucor miehei (RML) and Rhizopus oryzae (ROL) in the production of STAG, are evaluated. Four different support materials utilizing adsorption and one with covalent binding are investigated. Ammonium sulfate is found to significantly increase the activity-based immobilization yield (12% and 38% for RML and ROL, respectively) and specific activity on Accurel MP1000 (MP1000) when used as the immobilization buffer. Furthermore, the immobilization principle and support material influenced both the activity and regiospecificity. Immobilization by adsorption is found to result in higher catalytic activity, while covalent binding resulted in lipase inactivation. For RML, the highest specific activity of 43 µmol STAG min−1 g−1 (U) is obtained on MP1000, while ROL, which exhibited higher activities in general, results in a maximum activity of 120 U on Lifetech ECR8806. The obtained specific activites are comparable to the commercial preparations Novozym 40086 (45 U) and Lipase DF “Amano” IM (147 U) while the regiospecificity of the developed preparations is even higher, forming at least 64% less byproduct. Practical applications: There is an increasing need for lipids with specific nutritional and physical properties in health, nutrition, and food applications. In this context, STAG are highly promising products due to the possibility to tailor the composition to obtain the desired properties. Immobilized lipases are the catalyst of choice for the production of STAG, in which activity and regioselectivity are particularly important parameters for the process performance. In this study, it is shown that these parameters can be affected by the immobilization conditions and support material. Immobilized preparations with high activity and excellent regiospecificity are created on commercially available supports. This shows the possibility of STAG synthesis with high purity and beneficial properties.
|
|
| 9. |
- Cheng, Ken, et al.
(författare)
-
Decontaminated fishmeal and fish oil from the Baltic Sea are promising feed sources for Arctic char (Salvelinus alpinus L.)-studies of flesh lipid quality and metabolic profile
- 2016
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 118, s. 862-873
-
Tidskriftsartikel (refereegranskat)abstract
- The Baltic Sea is one of the world's most pollution-threatened brackish environments and limited direct consumption of fatty fish from the Baltic Sea is recommended. The use of decontaminated Baltic Sea fish raw materials as fish feed could be a strategy to recycle Baltic Sea nutrients back into food chain, while relieving pressure on aqua-feed in the growing aquaculture industry. In this study, defatted fishmeal and semi-purified fish oil from the Baltic Sea were used in fish feeds for Arctic char (Salvelinus alpinus L.). The effects of the Baltic Sea-sourced fish feeds on flesh lipid quality and fish metabolomics, compared with a standard commercial feed as a control, were determined. 1H NMR-based metabolomics studies indicated disturbances in energy metabolism and hepatic toxicity in fish fed both crude fishmeal and crude fish oil, associated with up-regulation (IGF-I, GHR-I, PPARα, PPARβ1A) and down-regulation (SREBP-1 and FAS) of hepatic genes expression. The content of n-3 long chain polyunsaturated fatty acids was not affected by the decontamination process. Thus, this short-term study demonstrates that decontaminating Baltic Sea-sourced fishmeal and fish oil reduces adverse effects in Arctic char. Practical applications: Decontaminated fish materials from the Baltic Sea were shown to be promising feed ingredients for Arctic char (Salvelinus alpinus L.) compared with untreated Baltic Sea-sourced fish feed, which induced changes in fish physiology associated with energy metabolism and hepatotoxicity. Baltic Sea-sourced fish materials containing high levels of long chain polyunsaturated fatty acids are valuable feed ingredients. The Baltic Sea-sourced fishmeal (CFM and DFM) and fish oil (CFO and SPFO) were tested in fish feeds for Arctic charr (Salvelinus alpinus), compared with a commercial diet as a control. Flesh lipid quality, metabolic profile in liver and muscle and hepatic gene expression (IGF-I, GHR-I, SREBP-1, etc.) were evaluated.
|
|
| 10. |
- Dahlenborg, Hanna, et al.
(författare)
-
Study of the porous structure of white chocolate by confocal Raman microscopy
- 2012
-
Ingår i: European Journal of Lipid Science and Technology. - : Wiley. - 1438-7697 .- 1438-9312. ; 114:8, s. 919-926
-
Tidskriftsartikel (refereegranskat)abstract
- Confocal Raman microscopy has been shown to be a useful technique for investigation of white chocolate surfaces. The appearance of protrusions and pores, and the distribution of fat, sucrose, and milk powder at and below the surface of white chocolate pralines were investigated using confocal Raman microscopy. Raman horizontal and depth scans showed that the protrusions and pores continue at least 10 mu m into the chocolate shell and that some protrusions and channels mainly consist of fat, while some consisted of a fat layer, leaving a hollow space underneath. Further, the pores and their continuing channels consisted of nothing but air. These findings indicate that the protrusions might be connected to channels where we suggest a pressure driven convective flow of liquid fat from within the chocolate matrix that, depending on temperature, moves up to the surface or goes back into the matrix, leaving an empty pore with a shell of fat at the surface, which in some cases collapse and leaves a hollow pore and channel. Therefore, these findings support that the protrusions could be connected to oil migration in chocolate and, thus, further to fat bloom development. Practical applications: Confocal Raman microscopy can be used to investigate the local distribution of different components in white chocolate. This technique offers the possibility to acquire the local distribution of different components within the sample, with a resolution down to the optical diffraction limit. Further, the analysis can be performed at ambient conditions, without requiring any special sample preparation or marker molecules. The results obtained by using this technique suggest that specific surface imperfections on chocolate could be part of a network of pore structures at and beneath the chocolate surface, which could be related to oil migration and thus, to fat bloom formation.
|
|
