Reversed-phase high-performance liquid chromatography purification of methyl esters of C(16)-C(28) polyunsaturated fatty acids in microalgae, including octacosaoctaenoic acid [28:8(n-3)

A preparative reversed-phase (RP; C(18)) high-performance liquid chromatography (HPLC) method with gradient elution using acetonitrile (MeCN)-chloroform (CHCl(3)) (or dichloromethane (DCM)) and evaporative light-scattering detection (ELSD) with automatic multiple injection and fraction collection was used to purify milligram quantities of microalgal polyunsaturated fatty acids (PUFA), separated as methyl esters (ME). PUFA-ME purified included methyl esters of docosahexaenoic acid (DHA; 22:6(n-3)), eicosapentaenoic acid (EPA; 20:5(n-3)) and the unusual very long-chain (C(28)) highly unsaturated fatty acid (VLC-HUFA), octacosaoctaenoic acid [28:8(n-3)(4, 7, 10, 13, 16, 19, 22, 25)] from the marine dinoflagellate Scrippsiella sp. CS-295/c. Other PUFA purified from various microalgae using this RP-HPLC method to greater than 95% purity included 16:3(n-4), 16:4(n-3), 16:4(n-1) and 18:5(n-3). The number of injections required was variable and depended on the abundance of the desired PUFA-ME, and resolution from closely eluting PUFA-ME, which determined the maximum loading. The purity of these fatty acids was determined by electron impact (EI) GC-MS and the chain length and location of double bonds was determined by EI GC-MS of 4,4-dimethyl oxazoline (DMOX) derivatives formed using a low temperature method. Advantages over silver-ion HPLC for purifying PUFA-ME is that separation occurs according to chain length as well as degree of unsaturation enabling separation of PUFA-ME with the same degree of unsaturation but different chain length (i.e. between 18:5(n-3) and 20:5(n-3)). In addition, PUFA-ME are not strongly adsorbed, but elute earlier than their more saturated corresponding FAME of the same chain length. This method is robust, simple, and requires only a short re-equilibration time. It is a useful tool for preparing milligram quantities of pure PUFA-ME for bioactive screening (as free fatty acids), although many multiple injections may be required for minor PUFA-ME. It also enabled dose-response and structure-activity studies to be carried out. It can be used for the enrichment of low levels of VLC-HUFA-ME to facilitate elucidation of their chemical structure and so is a useful adjunct to EI GC-MS of DMOX derivatives and other techniques such as NMR, which requires milligram quantities of purified compounds.     

Lipids from the Marine Alga <Emphasis Type="Italic">Gracilaria verrucosa</Emphasis>

The composition of lipids and fatty acids from the red alga Gracilaria verrucosa, for which a high content of 20:4n-6 acid is typical, was studied. The principal lipids were digalactosyldiacylglycerides, phosphatidylcholines (PC), monogalactosyldiacylglyderides (MGDG), and sulfoquinovosyldiacylglycerides, the fraction of each was approximately the same. Sphingophospholipids, inositephosphoceramides, were identified among the polar lipids. Each lipid class differed in the ratio of fatty acids (FA). The FA of all glycerolipids contained 20:4n-6 acid but its concentration was greatest in MGDG and PC, 67.2% and 56.5% of the acid mass.__________Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 230–232, May–June, 2005.     

Effects of UV Radiation and Diet on Polyunsaturated Fatty Acids in the Skin,Ocular Tissue and Dorsal Muscle of Atlantic Salmon (Salmo salar) Held in Outdoor Rearing Tanks

The effect of UV radiation (UVR) on juvenile Atlantic salmon (Salmo salar) was assessed by measuring the fatty acid (FA) profiles of muscle, dorsal and ventral skin, and ocular tissues following 4-month long exposures to four different UVR treatments in outdoor rearing tanks. Fish were fed two different diets (Anchovy- and Herring-oil based) that differed in polyunsaturated fatty acid (PUFA) concentrations. Anchovy-fed salmon had higher concentrations of ALA (alpha-linoleic acid; 18:3n-3), EPA (eicosapentaenoic acid; 20:5n-3) and DPA (docosapentaenoic acid, 22:5n-3) in their muscle tissues than fish fed the Herring feed. Fish subjected to enhanced UVB levels had higher concentrations of LIN (linolenic acid, 18:2n-6) and ALA, total omega-6 FA and SAFA (saturated fatty acids) in their tissues compared with fish in reduced UV treatments. Concentrations of ALA, LIN, GLA (gamma-linolenic acid; 18:3n-6), EPA, PUFA and total FA were higher in ventral skin of fish exposed to enhanced UVB compared with fish in reduced UV treatments. Salmon exposed to reduced UV weighed more per-unit-length than fish exposed to ambient sunlight. The FA profiles suggest that fish exposed to UV radiation were more quiescent than fish in the reduced UV treatments resulting in a buildup of catabolic substrates.     

Anti-Inflammatory and Anti-Platelet Properties of Lipid Bioactives from Apple Cider By-Products

The valorization of food industry by-products as sources of bioactive compounds is at the forefront of research in functional foods and nutraceuticals. This study focuses on bioactives of apple cider by-products (ACBPs) with putative cardio-protective properties. Total lipids (TLs) were extracted from ACBPs of apple varieties that are low (ACBP1), medium (ACBP2), and high (ACBP3) in tannins and were further separated into polar lipids (PLs) and neutral lipids (NLs). The functionality of these lipid extracts and of their HPLC-derived lipid fractions/PL subclasses were assessed in vitro against human platelet aggregation induced by the thrombotic and inflammatory platelet agonists platelet-activating factor (PAF) and adenosine diphosphate (ADP). The fatty acid profile of PLs and their most bioactive lipid fractions were evaluated by GC–MS analysis. The PL extracts exhibited higher specificity against the PAF-induced platelet aggregation compared to their anti-ADP effects, while TL and NL showed lower bioactivities in all ACBPs. HPLC analysis unveiled that the most bioactive PL from all ACBPs were those in PL fraction 3 containing phosphatidylcholines (PCs). PLs from all ACBPs and their PC bioactives were rich in polyunsaturated fatty acids (PUFAs) and especially in the essential omega-6 (n-6) linoleic acid (LA) and omega-3 (n-3) alpha linolenic acid (ALA), with favorably low values of the n-6/n-3 PUFA ratio, thus providing a rationale for their higher anti-inflammatory bioactivities. Within this study, highly bioactive PL compounds with strong anti-inflammatory and anti-platelet properties were identified in ACBPs, which can be potentially utilized for producing cardio-protective functional foods and/or nutraceuticals.     

Production of aliphatic aldehydes on peroxidation of various types of lipids.

IN vitro peroxidation by air, or xanthine-xanthine oxidase (xanthine-XOD) was performed to estimate the production of aliphatic aldehydes from free polyunsaturated fatty acids (PUFA), triglycerides, phospholipids and rat liver microsomes and mitochondria. The aldehyde contents in peroxidized lipids were determined by liquid chromatography and fluorescence detection. In both peroxidation, pentanal, (E)-4-hydroxy-2-nonenal (4-HN), and hexanal were produced from omega-6 PUFA rich lipids and propanal was markedly enhanced by increasing the degree of fatty acid unsaturation. The ratios of 4-HN to hexanal production in xanthine-XOD peroxidation of the omega-6 PUFA rich lipids, and rat liver microsomes and mitochondria were much higher than those in air peroxidation. The ratios (4-HN/hexanal) obtained in microsomes and mitochondria by xanthine-XOD were similar to those in rat liver observed in vitamin E deficient studies. The determination of these aldehydes may be useful to estimate the kinds of fatty acids peroxidized and investigate in vivo lipid peroxidation mechanism.     

Capillary GLC fatty acid fingerprints of seed lipids—a tool in plant chemotaxonomy?

The fatty acid composition of the seed lipids of plants, in contrast to leaf lipids, may contain highly specific unusual fatty acids, which are often correlated to plant family. For example, petroselinic acid is typical for the Apiacea family, cyclopropene fatty acids are typical for the Malvaceae family, and cyclopentene-ring containing fatty acids for the Flacourtiaceae family. Other fatty acids may be characteristic for certain sub-families or only for certain species of plants within a family or genus. γ-Linolenic acid, Δ5–18:3 and Δ5–20:3 fatty acids and others may occur in several plant families, but are still linked to certain related species only. They can be analyzed by high-resolution capillary GLC. Particularly interesting is the situation in the family Ranunculaceae. GLC fingerprints of fatty acids are shown that may indicate a closer or less close relationship between species within this family.     

Determination of phospholipid fatty acid and triacylglycerol composition of rat caecal mucosa.

The lipid composition of rat caecal mucosa, including the fatty acid composition of phospholipids and triacylglycerols, has been examined by capillary gas chromatography. Thirty-seven peaks were resolved, ranging in chain length from 12 to 24 carbon atoms. Preliminary identification of fatty acids by comparison with authentic standards was confirmed by gas chromatography-mass spectrometry using electron-impact ionization. The neutral and polar components were examined. Fatty acid methyl esters were quantified in absolute amounts with respect to the percentage of total phospholipid and triacylglycerols. The results show significantly higher levels of 16:0, 18:0, 18:1(n-9), 18:1(n-7), 18:2(n-6) and 20:4(n-6) in phospholipids, and higher levels of 16:0, 18:1(n-9) and 18:2(n-6) in triacylglycerols. On the other hand, analysis of caecal triacylglycerols revealed sn-glycerol-palmitate-oleate-palmitate, sn-glycerol-palmitate-linoleate-palmitate and sn-glycerol-palmitate-linoleate-oleate as major components.     

Fatty acid profile of different species of algae of the Cystoseira genus: a nutraceutical perspective

The fatty acid (FA) composition of six macroalgae from the Cystoseira genus, namely Cystoseira compressa, Cystoseira humilis, Cystoseira tamariscifolia, Cystoseira nodicaulis, Cystoseira baccata and Cystoseira barbata, was determined. Polyunsaturated fatty acids (PUFA) corresponded to 29–46% of the total FA detected. C. compressa, C. tamariscifolia and C. nodicaulis stood out for their low PUFA/saturated fatty acid, low n-6 PUFA/n-3 PUFA ratios as well as favourable unsaturation, atherogenicity and thrombogenicity indices, suggesting a high nutritional value with potential applications in the nutraceutical industry.     

Marine macroalgae analyzed by mass spectrometry are rich sources of polyunsaturated fatty acids

Algae from cold water (Canada) and warm water (China) were analyzed for their total lipid content, and for their fatty acid (FA) composition and content. The major findings are that FA from Canadian algae are generally richer in polyunsaturated FA (PUFA), with a higher n-3/n-6 FA ratio, and a higher degree of total unsaturation. The 18 C, 4 double bonds FA (18 : 4 stearidonic acid, morotic acid as synonym) was detected in greater amounts in cold water samples. The high levels of total PUFA, and especially of n-3 FA in Canadian algae, suggests their possible utilizations for nutritional purposes.     

Reaction efficiency of organic alkalis with various classes of lipids during thermally assisted hydrolysis and methylation

Reaction efficiencies of two organic alkalis, tetramethylammonium hydroxide (TMAH) and trimethylsulfonium hydroxide (TMSH), with lipids during thermally assisted hydrolysis and methylation (THM) were examined focusing on (1) the types of lipids and (2) degree of unsaturation of fatty acid moieties. Different types of lipids such as triglycerides, phospholipids, free fatty acids and cholesteryl esters containing saturated, monounsaturated or polyunsaturated fatty acid (PUFA) residues were subjected to THM-gas chromatography (GC) in the presence of TMAH or TMSH. The obtained results revealed that the THM reaction using TMAH allowed almost quantitative methylation of saturated and monounsaturated fatty acid components independently of the classes of lipids. However, strong alkalinity of TMAH brought about isomerization and/or degradation of PUFA components. In contrast, the use of TMSH was effective to highly sensitive detection of PUFA as well as saturated and monounsaturated fatty acid components contained in triglycerides, phospholipids (phosphatidylcholines) and free fatty acids. On the other hand, TMSH was proved to react hardly with any kind of fatty acid residues in cholesteryl esters due to their steric hindrance.     

MODIFICATION OF MEMBRANE COMPOSITION, EICOSANOID METABOLISM, AND IMMUNORESPONSIVENESS BY DIETARY OMEGA-3 AND OMEGA-6 FATTY ACID SOURCES, MODULATORS OF ULTRAVIOLET-CARCINOGENESIS

Dietary sources of lipids containing predominantly n-3 or n-6 fatty acids (FA) have been examined for effect upon several potential pathophysiologic parameters. Epidermal, plasma, and red blood cell (RBC) membrane FA composition exhibited marked differences between animals fed the respective dietary lipid sources. Reduced levels of 18:1, 20:3 and 20:4 occurred in the n-3 FA fed animals which exhibited significantly higher levels of 20:5 and 22:6. Approximately equal levels of 18:2 were present in animals fed either diet. Despite marked differences in RBC membrane FA composition, only marginal effect upon osmotic fragility occurred. Lower levels of 20:3 and 20:4 found in n-3 fed animals could result from a deficit of elongase and/or delta 5-desaturase activity. Whether lower 20:4 levels in n-3 fed animals could rate-limit eicosanoid metabolism is unknown, but epidermal capacity to metabolise arachidonic acid in these animals was found to be closely related to n-6 FA intake. Animals fed n-3 FA exhibited markedly lower levels of plasma PGE2, even when the diet was supplemented with n-6 FA. In addition, UV-radiated animals receiving the n-3 FA source demonstrated a reduced (approximately 30%) response to inflammatory stimulus and a greater (4.5-fold) delayed hypersensitivity (DH) to dinitrochlorobenzene than animals fed the n-6 FA source. These data demonstrate that dietary lipid strongly influences tissue FA composition, eicosanoid metabolism, and, in the case of DH, at least one type of T-cell mediated immune response in UV-irradiated animals.     

Lipids of microalgae. I. Lipids and a protein hydrolysate fromMonochrysis lutheri

The class composition and the total fatty acid composition of the readily- and difficulty-extractable lipids and the amino acid composition of a protein hydrolysate of the dry biomass from the golden-yellow microalgaMonochrysis lutheri have been determined for the first time. It has been established that the difficulty-extractable lipids differ sharply from the readily extractable lipids in the composition of the neutral and glycolipid components and also in that of the fatty acids; 27% of the weight of the fatty acids of the latter is composed of the 20:4 and 20:5 species. The protein hydrolysate ofM. lutheri contains almost the whole set of essential fatty acids.     

Folded and unfolded conformations of the omega-3 polyunsaturated fatty acid family: ch(3)ch(2)[ch=chch(2)](b)[ch(2)](m)cooh: first principles study

Polyunsaturated fatty acids (PUFA) like stearidonic acid (SDA;18:4 n-3) eicosapentaenoic acid (EPA; 20:5 n-3), and docosahexaenoic acid (DHA; 22:6 n-3) and its chain fragment models were studied at B3LYP/6-31G(d) levels of theory. Significant conformations for the cis and trans isomers were selected to obtained the thermodynamic functions (DeltaH, DeltaS, DeltaG) for the cis-trans isomerization and for folding using the B3LYP/6-311+G(2d,p)//B3LYP/6-31G(d) level of theory. The structural analysis shows that there are significant differences in thermodynamic function of the trans- and cis-PUFAs. The trans-cis isomerization energy values reinforce the consistency and the relative accuracy of theoretical model calculations. The observed flexibility of naturally cis PUFAs could be explained by a very special "smooth basin" PES of the motif of sp(2)-sp(3)-sp(2) hybrid states as reported previously (J. Phys. Chem. A 2005, 109, 520-533). We assumed that intrinsic thermodynamic functions may describe this flexible folding process. The folding enthalpy as well as the folding entropy suggests that there is a new role of the cis-PUFAs in membranes: these cis isomers may have a strong influence on membrane stability and permeability. The average length of the cis helix and beta PUFA was approximated. The difference between the lengths of these two structures is approximately 10 A.     

Lipids of microalgae. I. Lipids and a protein hydrolysate fromMonochrysis lutheri

The class composition and the total fatty acid composition of the readily- and difficulty-extractable lipids and the amino acid composition of a protein hydrolysate of the dry biomass from the golden-yellow microalgaMonochrysis lutheri have been determined for the first time. It has been established that the difficulty-extractable lipids differ sharply from the readily extractable lipids in the composition of the neutral and glycolipid components and also in that of the fatty acids; 27% of the weight of the fatty acids of the latter is composed of the 20:4 and 20:5 species. The protein hydrolysate ofM. lutheri contains almost the whole set of essential fatty acids.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbekistan Republic, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 507–511, July–August, 1993.     

Identification and quantification of phosphatidylcholines containing very-long-chain polyunsaturated fatty acid in bovine and human retina using liquid chromatography/tandem mass spectrometry

The retina is one of the vertebrate tissues with the highest content in polyunsaturated fatty acids (PUFA). A large proportion of retinal phospholipids, especially those found in photoreceptor membranes, are dipolyunsaturated molecular species. Among them, dipolyunsaturated phosphatidylcholine (PC) molecular species are known to contain very-long-chain polyunsaturated fatty acids (VLC-PUFA) from the n-3 and n-6 series having 24-36 carbon atoms (C24-C36) and four to six double bonds. Recent interest in the role played by VLC-PUFA arose from the findings that a protein called elongation of very-long-chain fatty acids 4 (ELOVL4) is involved in their biosynthesis and that mutations in the ELOVL4 gene are associated with Stargardt-like macular dystrophy (STD3), a dominantly inherited juvenile macular degeneration leading to vision loss. The aim of the present study was to develop an HPLC-ESI-MS/MS method for the structural characterisation and the quantification of dipolyunsaturated PC molecular species containing VLC-PUFA and validate this methodology on retinas from bovines and human donors. Successful separation of phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS), PC, lyso-phosphatidylcholine (LPC) and sphingomyelin (SM) was achieved using a silica gel column and a gradient of hexane/isopropanol/water containing ammonium formate as a mobile phase. A complete structural characterisation of intact phosphatidylcholine species was obtained by collision-induced dissociation (CID) in the negative mode. Fatty acid composition and distribution can be clearly assigned based on the intensity of sn-2/sn-1 fragment ions. The PC species were characterised on bovine retina, 28 of which were dipolyunsaturated PC species containing one VLC-PUFA (C24-C36) with three to six double bonds. VLC-PUFA was always in the sn-1 position while PUFA at the sn-2 position was exclusively docosahexaenoic acid (DHA, C22:6n-3). Most of these VLC-PUFA-containing dipolyunsaturated PCs were detected and quantified in human retinas. The quantitative analysis of the different PC molecular species was performed in the positive mode using precursor ion scanning of m/z 184 and 14:0/14:0-PC and 24:0/24:0-PC as internal standards. The relationship between the MS peak intensities of different PC species and their carbon chain length was included for calibration. The main compounds represented were those having VLC-PUFA with 32 carbon atoms (C32:3, C32:4, C32:5 and C32:6) and 34 carbon atoms (C34:3, C34:4, C34:5 and C34:6). Dipolyunsaturated PCs with 36:5 and 36:6 were detected but in smaller quantities. In conclusion, this new HPLC-ESI-MS/MS method is sensitive and specific enough to structurally characterise and quantify all molecular PC species, including those esterified with VLC-PUFA. This technique is valuable for a precise characterisation of PC molecular species containing VLC-PUFA in retina and may be useful for a better understanding of the pathogenesis of STD3.     

气相色谱全分析海水和淡水养殖南美白对虾组织中脂肪酸组成与含量

采用超声提取-毛细管气相色谱法分析测定了海水养殖和淡水养殖的南美白对虾的肌肉和肝胰腺(中肠腺)中脂肪酸的组成与含量,以用于对虾繁殖与营养的研究。采用Folch 液超声提取对虾组织中的脂质,脂质经氢氧化钾-三氟化硼法甲酯化后上机分析。采用BPX70(60 m×0.25 mm i.d.)石英毛细管柱分离,火焰离子化检测器检测。以线性程序升温等当碳长度(ECLT)值结合标准品对照的方法对17种脂肪酸定性,用面积归一化法定量。结果表明,两种对虾的脂肪酸组成均以不饱和脂肪酸为主,而且不饱和多烯酸的含量明显高于不饱和单烯酸。两种对虾的肌肉脂肪酸中高度不饱和脂肪酸,如二十碳五烯酸(EPA)与二十二碳六烯酸(DHA)的总含量均较高,达20%以上;肝胰腺中EPA和DHA的总含量较低,为11%～17%。淡水虾中n-6族不饱和脂肪酸含量比海水虾高,海水虾中n-3族与n-6族脂肪酸含量之比值比淡水虾高。     

海蜇不同部位脂肪酸的组成研究

报道了黄海海域成熟海蜇不同部位脂肪酸的研究结果。利用GC-MS技术测定海蜇皮、海蜇头、海蜇生殖腺的脂肪酸组成。结果表明：海蜇含有30多种脂肪酸,3个部位的脂肪酸组成差别不大;海蜇中含有丰富的多不饱和脂肪酸,含量在36．2％～38．7％之间,其中二十二碳六烯酸(DHA)、二十碳四烯酸(AA)和二十碳五烯酸(EPA)含量较高。     

Capillary electrochromatographic enantioseparations using a packed capillary with a 3 microm OD-type chiral packing

A technique for separating methyl esters of monounsaturated fatty acids by argentation chromatography using silver nitrate-impregnated TLC plates is described. Monounsaturated fatty acid methyl esters are separated from polyunsaturated and saturated fatty acid methyl esters and the monounsaturated fatty methyl esters are resolved according to chain length. cis isomers are well resolved from the corresponding trans isomers. R(F) values for individual monounsaturated fatty acids are very reproducible. The potential of the technique in metabolic studies is demonstrated in the chain elongation of [14C]-18:1(n-9) and delta-9 desaturation of [14C]-18:0 by human skin fibroblasts. Recoveries of individual [14C]-fatty acids for scintillation counting exceed 94%.     

Quantitative analysis of aberrant fatty acid composition of zebrafish hepatic lipids induced by organochlorine pesticide using stable isotope-coded transmethylation and gas chromatography-mass spectrometry

Organochlorine pesticides have been extensively used worldwide for agricultural purposes. Due to their resistance to metabolism, a major public health concern has been raised. Aberrant hepatic lipid composition has been a hallmark of many liver diseases associated with exposure to various toxins and chemicals. And thus lots of efforts have been focused on the development of analytical techniques that can rapidly and quantitatively determine the changes in fatty acid composition of hepatic lipids. In this work, changes in fatty acid composition of hepatic lipids in response to DDT (dichlorodiphenyltrichloroethane) exposure were quantitatively analyzed by a gas chromatography-mass spectrometric approach based on stable isotope-coded transmethylation. It has been quantitatively demonstrated that polyunsaturated fatty acids including C20:3n3, C20:4n6, and C22:6n3 decrease in response to DDT exposure. However, saturated long chain fatty acids including C16:0, C18:0, as well as monounsaturated long chain fatty acid C18:1n9 consistently increase in a DDT-concentration-dependent manner. In particular, much higher changes in the level of hepatic C16:0 and C18:0 for male fish were observed than that for female fish. These experimental results are in accordance with qualitative histopathological analysis that revealed liver morphological alterations. The stable isotope-coded mass spectrometric approach provides a reliable means for investigating hepatotoxicity associated with fatty acid synthesis, desaturation, mitochondrial beta-oxidation, and lipid mobilization. It should be useful in elucidation of hepatotoxic mechanisms and safety assessment of environmental toxins.     

Interfacial & colloidal aspects of lipid digestion

Amongst the main issues challenging the food manufacturing sector, health and nutrition are becoming increasingly important. Global concerns such as obesity, the ageing population and food security will have to be addressed. Food security is not just about assuring food supply, but is also about optimising nutritional delivery from the food that is available [1]. Therefore one challenge is to optimise the health benefits from the lipids and lipid soluble nutrients.Colloid scientists have an affinity for lipids because they are water insoluble, however this presents a challenge to the digestive system, which has to convert them to structures that are less insoluble so they are available for uptake. Despite this, the human digestive system is remarkably effective at digesting and absorbing most lipids. This is primarily driven through maximising energy intake, as lipids possess the highest calorific value, which was a survival trait to survive times of famine, but is now an underlying cause of obesity in developed countries with high food availability.The critical region here is the lipid-water interface, where the key reactions take place to solubilise lipids and lipid soluble nutrients. Digestive lipases have to adsorb to the oil water interface in order to hydrolyse triacylglycerols into fatty acids and mono glycerides, which accumulate at the interface [2], and inhibit lipase activity. Pancreatic lipase, which is responsible for the majority of lipid hydrolysis, also requires the action of bile salts and colipase to function effectively. Bile salts both aid the adsorption of co-lipase and lipase, and help solubilise the lipolysis products which have accumulated at the interface, into mixed micelles composing bile salts and a range of other lipids, to facilitate transport to the gut mucosal surface prior to uptake and absorption.The process can be affected by the lipid type, as shorter chain, fatty acids are more easily absorbed, whereas the uptake of longer chain fatty acids, particularly the very long chain n-3 fatty acids from fish oils are dependent on source and so may depend on food microstructure for optimal uptake [3]. The uptake of some poorly water soluble nutrients are enhanced by the presence of lipids, but the mechanisms are not clear. In addition, controlling the digestion of lipids can be beneficial as slower release of lipids into the bloodstream can reduce risk of cardiovascular disease, and can promote gut feedback processes that reduce appetite.This presents an opportunity to colloid and interfacial science, as there are many unanswered questions regarding the specific physicochemical mechanisms underlying the process of lipid digestion and uptake. I will review our current knowledge of lipid digestion and present examples of how fundamental research in colloidal and interface science is beginning to address these issues. These include the adsorption behaviour of physiological surfactants such as bile salts; interfacial processes by which different polar lipids can influence lipolysis; and the effect of emulsion based delivery systems on cellular uptake of lipid soluble nutrients.A fundamental understanding of these processes is required if we are to develop intelligent design strategies for foods that will deliver optimal nutrition and improved health benefits in order to address the global challenges facing the food sector in the future.