Seal Blubber Oil Research Articles

MICROALGAE - MACROALGAE BASED NUTRACEUTICALS AND THEIR BENEFITS

Algae produce some substances that have a positive effect on human health. Algae are known as sources suitable for use in food and foods with the bioactive components they produce at a high rate. These ingredients are called nutraceuticals. Nutraceuticals are products that have physiological benefits and are protective against chronic diseases and are generally recommended to be used as medicines. Bioactive nutraceuticals from aquaculture; fish oil (ω-3), seal blubber oil, algae oil, shark liver oil, shark cartilage, chitin, chitosan as well as enzymes, peptides and their components, vitamins (vitamin A,D,E, β carotene), macroalgae and its components, protein hydrolysates and other products. It is known that these high-value components in algae regulate immunity, prevent diabetes, oxidation, inflammation, high cholesterol and cardiovascular diseases, and have positive effects against obesity and unbalanced nutrition. In this review, information is given about micro and macroalgae-based nutraceuticals, their application areas and potential health benefits.

Two step-production of acylglycerols containing a high proportion of docosapentaenoic acid from marine omega-3 oil and their oxidative stability

The objective of this study was to concentrate polyunsaturated fatty acid (PUFA) from seal blubber oil in an innovative manner to produce a high content of docosapentaenoic acid (DPA) in the resultant product. It also aimed at investigating the use of lipases as catalysts for synthesizing acylglycerols from glycerol and polyunsaturated fatty acid concentrates. Additionally, study of the oxidative stability of acylglycerols synthesized by lipases was intended. A two-stage urea complexation process was used to concentrate PUFA from seal blubber oil, giving rise to a DPA content of up to 24.0% in the product. Enzymatic synthesis of acyglycerols directly from glycerol and fatty acid concentrate was studied. Three lipases were used as biocatalysts for esterification. Lipase SP435 from Candida antarctica showed the highest activity for esterification. Effects of reaction parameters, namely temperature, time course and mole ratio of glycerol to fatty acid were followed with all three lipases. The optimal reaction time was 24 hr at 30 °C at a mole ratio of glycerol to fatty acid of 14:1. The maximum degree of acylglycerol synthesis was > 90%. The effect of time course and mole ratio of glycerol to fatty acid on acylglycerols distribution was also determined. The oxidative stability of different samples under Schaal-oven conditions at 60 °C showed that the oxidative stability of acylglycerols was better than that of the corresponding fatty acid esters.

Acidolysis of p-Coumaric Acid with Omega-3 Oils and Antioxidant Activity of Phenolipid Products in in vitro and Biological Model Systems

Lipase-catalyzed acidolysis of p-coumaric acid with seal blubber oil (SBO) and menhaden oil (MHO) was carried out, followed by identification of major phenolipids in the resultant acidolysis mixture using high-performance liquid chromatography/mass spectrometry. Separation of phenolipid components from the resultant acidolysis mixture was achieved using flash column chromatography. The antioxidant activities of the phenolipids were examined in in vitro assays and biological model systems. The major phenolipids identified from acidolysis mixtures with both SBO and MHO included eight phenolic monoacylglycerols and eight phenolic diacylglycerols. Phenolipids derived from SBO and MHO generally showed good antioxidant potential in the systems tested. The prepared phenolipids exhibited high scavenging capacity toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) and peroxyl radicals and displayed reducing power, strong inhibitory effect on bleaching of β-carotene, human low-density lipoprotein (LDL) cholesterol oxidation, as well as radical-induced DNA cleavage, thus suggesting that phenolipids derived from omega-3 oils may be used as potential stable products for health promotion and disease risk reduction.

Forensic Identification of Seal Oils Using Lipid Profiles and Statistical Models

Seal blubber oils are used as a source of omega-3 polyunsaturated fatty acids in Canada but prohibited in the United States and (FA) European Union. Thus, a reliable method is needed to identify oils originating from seals versus fish. Two lipid profiling methods, fatty acid analysis using gas chromatography and triacylglycerol (TAG) analysis using liquid chromatography and mass spectrometry, were applied with statistical models to discriminate commercial oils and blubber samples harvested from marine fish and seals. Significant differences were observed among FA profiles, and seal samples differed from each of the fish oils (p≤0.001). FA and TAG profiles were used to discriminate sample groups using a random forest classifier; all samples were classified correctly as seals versus fish using both methods. We propose a two-step method for the accurate identification of seal oils, with preliminary identification based on FA profile analysis and confirmation with TAG profiles.

Effect of maternally supplied n-3 and n-6 oils on the fatty acid composition and mononuclear immune cell distribution of lymphatic tissue from the gastrointestinal tract of suckling piglets

Fatty acids are essential for immune cell function. Maternal dietary fatty acid supply influences body fat composition of their offspring. As a first step to study immunonutritional interactions at an early age of pigs, four sows were fed a diet containing sunflower oil or oil from seal blubber during pregnancy and lactation. Corresponding piglets were sacrificed at three consecutive time points in the suckling period and their mesenteric lymph nodes and spleen were analysed by gas chromatography for levels of fatty acid. At the same time mononuclear cells of these organs and of the intestinal lymphoid tissue from the jejunum were isolated and subpopulations characterised by flow cytometry. Levels of fatty acids from the lymphatic organs of the piglets were significantly influenced by the maternal diet. The concentration of the fatty acids 20:5n-3, 22:5n-3 and 22:6n-3 were higher in the spleen and mesenteric lymph node of piglets suckled to sows of the test diet. Additionally, suckling time affected the levels of some long chain polyunsaturated fatty acids. Dietary effects were seen on some subpopulations including CD4−CD8α+ lymphocytes of the mesenteric lymph nodes and CD4+CD8α+ lymphocytes of the lamina propria, which were higher in the group fed seal blubber oil. The levels of CD21+ B-cells were higher in the group fed sunflower oil. The results indicate that the maternal diet and suckling time affect the fatty acid status of the investigated lymphatic tissues of piglets, but may have minor effects on the investigated lymphocyte subpopulations.

Effect of Enzymatic Randomization on Positional Distribution and Stability of Seal Blubber and Menhaden Oils

In an effort to investigate the effect of positional distribution on oxidative stability of menhaden and seal blubber oils, Novozyme 435 was used as a random biocatalyst. Positional distribution of fatty acids was determined using gas chromatography. As some of the α-tocopherol was lost during randomization, its content was adjusted to the level prior to the process to eliminate this effect on oxidative stability of oils tested. Conjugated dienes (CD) and thiobarbituric acid reactive substances (TBARS) were used as indicators of oxidative stability. The results showed that the polyunsaturated fatty acids were distributed predominantly at terminal positions in randomized menhaden oil, whereas they were distributed more evenly among all positions in enzymatically randomized seal blubber oil, compared to their unrandomized counterparts. Results of CD and TBARS values indicated that randomized menhaden oil was more stable than the original oil, whereas randomized seal blubber oil was more vulnerable to oxidation compared to its counterpart. Changes of oxidative stability after randomization were mainly due to positional redistribution of fatty acids, especially those of the polyunsaturated types.

Effect of Chemical Randomization on Positional Distribution and Stability of Omega-3 Oil Triacylglycerols

Randomization has been commonly used to modify the chemical and physical properties of natural fats and oils. In this study, seal blubber oil (SBO) and menhaden oil (MHO) were modified through chemical randomization using sodium methoxide, and the effect on positional distribution of fatty acids was investigated using gas chromatography (GC) and (13)C nuclear magnetic resonance (NMR) spectroscopy. The effect of randomization on the stability of the original oils and their randomized counterparts was analyzed by comparing conjugated dienes and thiobarbituric acid reactive substances (TBARS) values after accelerated oxidation at 60 degrees C for 4 days. The omega-3 polyunsaturated fatty acids (PUFA) were distributed more evenly among the terminal sn-1,3 positions and the middle sn-2 position in chemically randomized oils when compared to the starting oils. The effect was more pronounced for SBO with omega-3 PUFA attached preferentially to sn-1,3 positions of triacylglycerols before randomization, and it was less pronounced for MHO, which contained omega-3 PUFA more evenly distributed before randomization. However, different levels of commonly known omega-3 fatty acids, namely, docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), eicosapentaenoic acid (EPA), and stearidonic acid (STA), were obtained in both original and randomized oils from GC and (13)C NMR spectroscopy. The stability of the randomized oils was also affected to different degrees, depending on the storage time.

A randomized double blind comparison of short-term duodenally administrated whale and seal blubber oils in patients with inflammatory bowel disease and joint pain

Compared with soy oil, 10 days treatment with seal oil (SO), 10 mL×3 daily, self-administrated through a nasoduodenal feeding tube, relieves joint pain in patients with inflammatory bowel disease (IBD). This randomized, controlled, double blind pilot trial compares SO and whale oil (WO) administered similarly by duodenal tube, for 10 days in 18 patients with IBD-related joint pain ( n=9 per group). Other long chain n-3 polyunsaturated fatty acids were prohibited 7-days prior to and during study. Significant changes from baseline to study end were observed in both groups: reduced plasma arachidonic acid to eicosapentaenoic acid ratio and prostaglandin E 2 (PGE 2) levels (tendency in WO group), decreased IBD-related joint pain and IBD-disease activity, and improved quality of life. These changes were not significantly different between SO and WO groups. Inhibition of cyclooxygenase is consistent with amelioration of IBD-related joint pain, but, as active control was used, effects need confirmation.

Trapping Effects of Green and Black Tea Extracts on Peroxidation-Derived Carbonyl Substances of Seal Blubber Oil

Green and black tea extracts were employed to stabilize seal blubber oil at 60 degrees C for 140 h. On the basis of the headspace SPME-GC-MS analysis, with the addition of green/black tea extracts, the contents of acetaldehyde, acrolein, malondialdehyde, and propanal, four major lipid peroxidation products, were reduced. The inhibition rates of acrolein formation by green tea and black tea extracts were 98.40 and 96.41% respectively, and were 99.17 and 98.16% for malondialdehyde, respectively, much higher than the inhibition of the formation of acetaldehyde and propanal. Because malondialdehyde and acrolein are reactive carbonyl species (RCS) and recent studies have suggested that phenolics can directly trap RCS, this study also investigated whether green tea polyphenols can trap acrolein or not. Acrolein was reduced by 90.30% in 3 h of incubation with (-)-epigallocatechin-3-gallate (EGCG). Subsequent LC-MS analysis revealed the formation of new adducts of equal molars of acrolein and EGCG. The reaction site for acrolein was elucidated to be the A ring of EGCG as evidenced by LC-MS/MS analysis and by testing of the acrolein-trapping capacities of the analogous individual A, B, and C rings of EGCG. Thus, EGCG's direct trapping of RCS may also contribute to the significant reduction of acrolein and other aldehydes in the peroxidation of seal blubber oil.

Phenotypic and functional aspects of the neonatal immune system as related to the maternal dietary fatty acid supply of sows

The maternal-fetal transfer and subsequent uptake of sow milk enriched with n-6- or n-3-polyunsaturated fatty acids may not only influence neonatal body fat but may also have an impact on the immune function of newborn piglets. Sows were fed a diet containing sunflower oil as n-6-source or oil from seal blubber with long chain polyunsaturated n-3-fatty acids during pregnancy and lactation. Sow serum was investigated during pregnancy and serum and milk during lactation; piglet serum and liver were investigated in the suckling period until day 19. Piglet leukocyte subpopulations were characterised by flow cytometry and leukocyte proliferation was tested after stimulation with mitogens. No differences were noted in performance. The serum and milk fatty acid status of the sows was markedly influenced by the diet. Eicosapentaenoic acid (20:5n-3), 22:5n-3 and 22:6n-3 were higher (p < 0.001) in serum and liver of piglets delivered from sows fed the seal blubber oil. Piglets at birth had lower lymphocyte counts (p < 0.01) than piglets 19 days after birth. However, no influence of feeding the different oil sources was noted on lymphocyte phenotyping and leukocyte proliferation test. The results of the present study show that the maternal diet affected the fatty acid status of neonates, but much more in the sucking period. Immunological traits were not affected, probably as the mononuclear cell lineage is too immature around birth. Effects of PUFA n-3 might only be seen at a later time point or in the polymorphonuclear cell lineage as they were dominating right after birth.

ACIDOLYSIS OF SEAL BLUBBER OIL WITH LAURIC ACID

ABSTRACT The purpose of this study was to modify the fatty acid composition of seal (Phoca groenlandica) blubber oil by incorporation of lauric acid (12:0; a medium chain fatty acid). Of the three enzymes that were employed in the initial screening, sn‐1,3‐regiospecific lipase from Mucor miehei (Lipozyme IM) exhibited the highest activity and was further studied for the acidolysis of seal blubber oil with 12:0. The fatty acid composition of modified seal blubber oil was different from that of the unaltered oil. The optimum substrate mole ratio of seal blubber oil to 12:0 for M. miehei lipase was 1:3. The time course of the reaction demonstrated that 29.7% lauric acid incorporation was obtained in 24 h. Stereospecific analyses by pancreatic lipase revealed that M. miehei lipase incorporated 12:0 predominantly at the sn‐1 and sn‐3 positions of the triacylglycerol molecules.

High performance liquid chromatography-tandem mass spectrometry of phospholipid molecular species in eggs from hens fed diets enriched in seal blubber oil

The total lipid fraction of eggs from hens fed diets enriched in seal blubber oil (1.25–5.0% SBO) was directly analysed with normal-phase high performance liquid chromatography coupled on-line with electrospray ionization ion-trap tandem mass spectrometry (HPLC-ESI-MS–MS) for the identification of the molecular species of phospholipids (PLs). The species of phosphatidylethanolamine (PE) and phosphatidylinositol (PI) were all detected as the [M − H] − ions. The phosphatidylcholine (PC), sphingomyelin (Sph) and lysophosphatidylcholine (LPC) classes, were detected as formate adducts [M + HCOO] −. Tandem MS of PE and PI showed the loss of the carboxylate anions, and, for PI, also the loss of water and inositol. Product ion spectrum of PC, LPC and Sph contained only the [M − CH 3] − ion fragment. Feeding different levels of SBO for 5 weeks resulted in a significant increase of PE, PC and PI molecular species carrying eicosapentaenoic acid (C 20:5 ω3 , EPA), docosapentaenoic acid (C 22:5 ω3 , DPA) and docosahexaenoic acid (C 22:6 ω3 , DHA), but not Sph nor LPC. The highest increase of the ω3/ω6 ratio occurred for PE and PC. On the contrary, PI was less affected by the increase of SBO in the diet.

Oxidation of all‐ cis ‐7,10,13,16,19‐docosapentaenoic acid ethyl ester. Hydroperoxide distribution and volatile characterization

The isomeric hydroperoxide distribution and the composition of volatiles generated by oxidation of all-cis-7,10,13,16,19-docosapentaenoic acid ethyl ester (DPA Et) were determined. DPA Et was prepared by using seal blubber oils as raw material and purified by urea complexation and reverse-phase high-performance liquid chromatography (HPLC). The DPA Et of over 96% purity thus obtained was dissolved in methanol and subsequently divided into two portions. One portion was added with methylene blue and exposed to a tungsten bulb light at 5 °C for photosensitized oxidation. The other portion was added with 2,2'-azobis (2,4-dimethylvaleronitrile) as an azo-radical initiator and kept in the dark at room temperature for autoxidation. Positional isomers of hydroperoxides generated by autoxidation or photosensitized oxidation of DPA Et were separated by normal-phase HPLC and detected by a fluorescence detection system as well as UV absorption. The peak components were identified by gas chromatography-mass spectrometry (GC-MS). Eight isomeric hydroperoxides, including certain amounts of 7-, 10-, 11-, 13-, 14-, 16-, 17-, and 20-hydroperoxy docosapentaenoate, were generated by autoxidation of DPA Et. The photosensitized oxidation of DPA Et yielded not only the above eight hydroperoxide isomers but also two additional isomeric hydroperoxides, 8- and 19-hydroperoxy docosapentaenoate, which are characteristic hydroperoxide isomers generated by singlet oxygen-mediated oxidation. Volatiles formed by autoxidation of DPA Et at 50 °C were collected and analyzed by solid-phase micro-extraction and GC/GC-MS. A number of aldehydes, ketones, alcohols, acids, furans and hydrocarbons were identified. The formation mechanisms of certain volatiles are discussed.

Positional analysis of egg triacylglycerols and phospholipids from hens fed diets enriched with refined seal blubber oil

AbstractThe effect of feeding laying hens with refined seal blubber oil (SBO, containing 22.2% ω3 polyunsaturated fatty acids) on the fatty acids composition and regiospecific distribution of fatty acids in triacylglycerols (TAG) and phospholipids (PL) of egg produced was investigated. The hens were fed four diets containing 0 (control), 1.25, 2.5 or 5% SBO for 5 and 9 weeks. Comparison of the total fatty acids composition indicated that a 5 week feeding period was sufficient to obtain the highest amount of total polyunsaturated fatty acids in the eggs. The fatty acids composition of the egg lipids reflected the fatty acids composition of the diet. The substantial reduction in the ω6/ω3 ratio (ie 8.5 to 2.6) is of interest, and is in line with the recommendations of health authorities in several countries, where it has been suggested that the human diet should contain a ω6/ω3 ratio of 3–4. The greatest reduction of the ω6/ω3 ratio occurred for diet A (control) and diet B (1.25% SBO). Principal component analysis analysis of the fatty acids composition of egg lipid showed four clusters representing: (i) the control diet; (ii) the diet containing 1.25% SBO as well as samples obtained from feeding 2.5% SBO for 9 weeks; (iii) the diet with 5% SBO; and (iv) samples obtained from hens fed 2.5% SBO for 5 weeks. More ω‐3 polyunsaturated fatty acids (ω3 PUFA) were incorporated in phosphatidylethanolamine and phosphatidylcholine than in TAG.Although ω3 were predominantly linked in the position Sn‐1,3 of TAG in SBO, they were esterified in the Sn‐2 position of the TAG and PL of eggs obtained after feeding laying hens with enriched diets. Copyright © 2005 Society of Chemical Industry

Effect of different sources of dietary omega‐3 fatty acids on general performance and fatty acid profiles of thigh, breast, liver and portal blood of broilers

AbstractOne hundred and sixty‐eight 1‐day‐old Cobb broiler chickens were randomly assigned to 12 broiler cages to determine the dietary effect of different sources of oils rich in long‐chain omega‐3 polyunsaturated fatty acids (LCω3PUFA). The following oils were added to the feed at a concentration of 12.5 g kg−1: a highly refined seal blubber oil (SBO) containing 225 g kg−1 LCω3PUFA; a fish oil (FO) concentrate containing &gt;800 g kg−1 LCω3PUFA in the form of triglycerides; and an FO concentrate containing &gt;600 g kg−1 LCω3PUFA in the form of ethyl esters. Fatty acid profiles of the breast and thigh meat were measured in order to determine the deposition of LCω3PUFA into the body tissues, whilst fatty acid profiles of the liver and the portal blood were taken in order to deduce consequences of the different ester forms on the absorption process. A triangular sensory evaluation was performed on the breast meat. The levels of LCω3PUFA in all tissues and the portal blood reflected the concentrations of LCω3PUFA in the diets. The sensory properties of the breast meat were negatively influenced by ethyl ester supplementation only. Copyright © 2004 Society of Chemical Industry

Feeding Laying Hens Seal Blubber Oil: Effects on Egg Yolk Incorporation, Stereospecific Distribution of Omega-3 Fatty Acids, and Sensory Aspects

Seventy-two 26-wk-old Single Comb White Leghorn laying hens were randomly assigned to 36 cages (2 per cage) in a 3-orthogonal 4 × 4 latin square, with the fourth row suppressed, to assess the effect of feeding refined seal blubber oil (SBO, containing 22.2% omega-3 fatty acids) on the fatty acid composition and position in the egg yolk lipids. The experiment was conducted over a period of 9 wk. Eggs were collected and numbered, and the weights were recorded for each week and cage. Eggs collected at wk 5 and 9 were used for total lipid, lipid class, fatty acid, and positional analyses. Sensory evaluation was carried out on eggs collected at wk 6 and 7. Feeding SBO at 1.25% led to an increase (P < 0.0001) in the long-chain omega-3 polyunsaturated fatty acids (LCn3PUFA) and a concomitant decrease (P < 0.0001) in arachidonic acid (ARA) in the egg yolk lipids. Yet this amount of SBO in the diet had no effect (P > 0.1) on the sensory attributes of the egg and on production parameters such as egg weight, number of eggs laid, and feed intake (P > 0.05). When feeding SBO in amounts higher than 1.25% proportionately, a plateau effect of the LCn3PUFA content of the eggs was observed. This appears to be because the PUFA content in the sn-2 position of the phospholipids cannot exceed a certain amount. When this amount is reached, the LCn3PUFA will be increasingly stored in triglycerides. The results presented here clearly indicate how eggs can be produced with optimized composition of LCn3PUFA without affecting (P > 0.1) the sensory properties of the eggs. The procedures elaborated herein provide directly applicable consequences for the food industry.

Enzyme-catalyzed synthesis of structured lipids via acidolysis of seal ( Phoca groenlandica) blubber oil with capric acid

A structured lipid (SL) containing n-3 fatty acids (eicosapentaenoic acid, 20:5n-3; docosahexaenoic acid, 22:6n-3) and capric acid (10:0; a medium chain fatty acid) was prepared using lipase-catalyzed acidolysis of seal blubber oil with capric acid. An immobilized lipase, Lipozyme-IM from Mucor miehei, was used as the biocatalyst. Acidolysis reactions were carried out in hexane and the products were analyzed by gas chromatography. Incorporation of capric acid was affected by mole ratio of substrates, type of organic solvent, reaction temperature, reaction time, water content and the amount of lipase. The optimum reaction mixture and conditions were oil/fatty acid mole ratio of 1:3, hexane, 45 °C, 24 h, 1% (w/w of substrates) water and 10% (w/w of substrates) Lipozyme-IM lipase. Under these conditions, a SL containing 2.3% 20:5n-3, 7.6% 22:6n-3 and 27.1% 10:0 was obtained. Solvents with log P values between 2.5 and 4.5 performed the acidolysis reaction better than those with log P values of less than 2.5. However, in the absence of any organic solvent, Lipozyme-IM afforded a satisfactory incorporation of capric acid into seal blubber oil.

Seal blubber oil and its long-chain polyunsaturated fatty acids: processing technologies and applications

Seal blubber oil and its long-chain polyunsaturated fatty acids: processing technologies and applications

Enzyme‐assisted acidolysis of menhaden and seal blubber oils with γ‐linolenic acid

AbstractOils containing both n−3 and n−6 fatty acids have important clinical and nutritional applications. Lipase‐catalyzed acidolysis of seal blubber (SBO) and menhaden oils (MO) with γ‐linolenic acid (GLA) was carried out in hexane. The process variables studied for lipase‐catalyzed reaction were concentration of enzyme (100–700 units/g of oil), reaction temperature (30–60°C), reaction time (0–48 h), and mole ratio of GLA to triacylglycerols (TAG) (1∶1 to 5∶1). Two lipases chosen for acidolysis reaction were from Pseudomonas species (PS‐30) and Mucor miehei. Lipase PS‐30 was chosen over Mucor (also known as Rhizomucor) miehei to catalyze the acidolysis reaction owing to higher incorporation of GLA. For the acidolysis reaction, optimal conditions were a 3∶1 mole ratio of GLA to TAG, reaction temperature of 40°C, reaction time of 24 h, and an enzyme concentration of 500 units/g of oil. Under these conditions, incorporation of GLA was 37.1% for SBO and 39.6% for MO.

LIPOLYTIC ACTIVITY OF ENZYMES FROM GERMINATING SEEDS OF SESAME (SESAMUM INDICUM L.)

ABSTRACTSesame (Sesumum indicum) seeds were germinated for seven days under laboratory conditions and the lipolytic activity of the defatted, dried seedlings was determined. Germination increased the lipolytic activity of sesame seeds and the highest activity was observed on day‐4. The lipases of four days germinated sesame seeds were able to hydrolyze mainly the saturated fatty acids from seal blubber oil (SBO). Reaction temperature, incubation period and oil‐to‐seedling powder ratio had a significant effect on the hydrolysis of saturated fatty acids, thereby concentrating unsaturated (mono‐ and polyunsaturated) fatty acids of seal blubber oil.