Kappa-carrageenan as an effective cryoprotectant on water mobility and functional properties of grass carp myofibrillar protein gel during frozen storage

The effect of kappa-carrageenan oligosaccharides was analyzed on the gelling abilities of grass carp myofibrillar proteins (MP) during 60 days frozen storage. Four gel treatments were prepared: control without additives (C), a positive control with sucrose: sorbitol (PC), and two batches with 1 and 2% of kappa-carrageenan (KC). All MP gels showed a significant decline in the functional and structural properties. Water holding capacity (WHC) and textural properties of control MP gel was significantly reduced due to oxidative changes, whereas weak cross-linking between amino acid molecules and denaturation of myosin observed. In contrast, PC and KC showed a significant control on the reduction of functional properties due to the enhanced inter/intra-molecular interactions and less formation of ice crystals. Addition of KC (2%) significantly restricted the decline in WHC from 95.45 to 75.47%, which is well associated with high hydrogen proton density. Besides that, low field nuclear magnetic resonance (LF-NMR) analysis exhibited a restricted increase in T22 relaxation time in samples added with KC (2%). Overall, MP gel with KC (2%) proved to be an effective alternative in comparison with PC and could be efficient in the production and commercialization of fish and other seafood products.National Natural Science Foundation of China | Ref. 31972104National Natural Science Foundation of China | Ref. 51809224National Natural Science Foundation of China | Ref. 3147169

Nikolai Anichkov and one hundred years of the hypothesis about cholesterol and atherogenesis

The relationship of cholesterol to atherogenesis already fulfilled one hundred years. The merit of this important discovery is attributed to a Russian military doctor, Nikolai Anichkov, who using rabbits as experimental model, was able to show the accumulation of “lipoids” when he fed animals with a diet rich in cholesterol. His experimental observations were criticized by many researchers, since he used an animal that is not carnivorous, so it was an inappropriate model. Anichkov published very few scientific articles, and all of them in Russian language. Only in 1933 he could make public his work to the Western world by publishing a review on his scientific work in English. Was only in 1984 when the scientific community recognized the merit of his research, which was pioneer in the understanding that we have today about the relationship of artherogenesis and cholesterol.La relación del colesterol con la aterogénesis ya cumplió cien años. El mérito de este importante descubrimiento lo tiene un médico militar ruso Nikolai Anichkov, quien utilizando conejos como modelo experimental, pudo demostrar la acumulación de "lipoides" cuando los alimentaba con una dieta rica en colesterol. Sus observaciones fueron criticadas por numerosos investigadores ya que utilizaba un animal que no es carnívoro, por lo cual era un modelo inadecuado. Anichkov publicó muy pocos trabajos científicos y todos ellos en idioma ruso. Solo en 1933 pudo hacer público su trabajo al mundo occidental al publicar en inglés una revisión sobre su trabajo científico. Tardíamente, en 1984, se reconoció por parte de la comunidad científica el mérito de su investigación, la que fue pionera en la comprensión que tenemos hoy día sobre la enfermedad arterioesclerótica y el colesterol

Comparison of fatty acid profiles of dried and raw by products from cultured and wild fishes

Fish by-products may become alternative sources of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). However, due to the high enzymatic activity in these biological tissues, special care must be taken to prevent lipid oxidation and hydrolysis. In this work, several by-products from Chilean fishes (farmed salmon and wild red cusk-eel and yellowtail kingfish) were dried at 105 degrees C for 3h to remove water and inactivate enzymes. The effect of temperature on EPA and DHA levels was assessed by comparing fatty acid profiles of raw and dried by-products. Drying at 105 degrees C for 3h was considered an adequate process to obtain dried powders from fish by-products with appreciable amounts of EPA and DHA, even though EPA and DHA values showed a certain decrease after drying. Several methodologies involving food-grade solvents were checked to evaluate their suitability for lipid extraction from dried by-products, being Soxhlet extraction with n-hexane identified as the most suitable process in terms of extraction yield and EPA/DHA values. Cholesterol amount was also studied, being the highest and lowest amounts found in liver and viscera from farmed salmon, respectively. Practical applications: In fish processing plants, raw by-products are collected after fish evisceration, and they can be transported to oil extraction facilities, although their lipids may be easily degraded unless special precautions are taken to preserve such biomass. Raw fish by-products must be subjected to water removal and enzyme inactivation to prevent lipid degradation and hydrolysis, and it is desirable that such actions are carried out in the processing plants themselves to ensure the maximum oil quality. Drying at 105 degrees C for a short time (3h) was assayed in this work because of its simplicity, low cost, scalability, and feasibility to be installed in fish processing plants. Soxhlet procedure with n-hexane is effective to extract lipids containing EPA and DHA from dried by-products for nutritional or nutraceutical purposes. Because of water removal, lipid extraction efficiency from dried by- products is enhanced and less solvent is needed, which is economically and environmentally desirable. Raw by-products from cultured and wild fishes are dried at 105 degrees C for 3h and fatty acid profiles are compared between raw and dried by-products to assess the potential decreasing effect of temperature on the levels of polyunsaturated fatty acids, especially EPA and DHA. Different lipid extractions using solvents are also compared to check their influence on fatty acid profiles. Additionally, cholesterol amount is quantified in the lipid fraction extracted from dried fish by-products.University of Chile UI008/1

Concentration of Gamma-Linolenic and Stearidonic Acids as Free Fatty Acids and Ethyl Esters from Viper's Bugloss Seed Oil by Urea Complexation

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim In this work, gamma-linolenic acid (GLA) and stearidonic acid (SDA) are successfully concentrated as free fatty acids (FFA) and ethyl esters (EE) using the urea complexation method at room temperature and two sources of these fatty acids: commercial Echium plantagineum seed oil as well as extracted oil from this species which is grown in Chile. Concentration factors (% fatty acid in the concentrate/% fatty acid in the original oil) for both fatty acids are found to be between 2.35 and 2.65, although they are more efficiently concentrated as FFA than as EE using both commercial and extracted oils. This is the first work which reports the use of Echium plantagineum seed oil from Chilean origin to produce GLA and SDA concentrates as FFA and EE, with similar results that those obtained with commercial Echium oil. Practical Applications: The interest for GLA and SDA as functional ingredients is increasing in the last few years because of th

Adding a purple corn extract in rats supplemented with chia oil decreases gene expression of SREBP-1c and retains Δ5 and Δ6 hepatic desaturase activity, unmodified the hepatic lipid profile

Flavonoids upregulate gene expression of PPAR-alpha and underregulate the gene expression of SREBP-lc, and their intake increases the plasmatic concentration of n-3 LC-PUFAs. However, the biological mechanisms underlying these effects have not been elucidated. In this work, the effect of oral supplementation of ALA from chia (Salvia hispanica L.) seed oil and anthocyanins from a purple com extract (PCE) on gene expression of SREBP-lc, PPAR and A5 alpha and A Delta 5desat Delta 6ases (A5D and(Delta 5), th Delta 6)tivity of these enzymes in the liver as well as the hepatic lipid profile were evaluated in thirty-six female Sprague Dawley rats whose diet was supplemented with olive oil (OL), chia oil (CH), olive oil and PCE (OL + PCE) or chia oil and PCE (CH + PCE). Gene expression of PPAR-a wk nif alpha cantly higher when supplemented with CH and CH + PCE, SREBP-lc gene expression was higher when supplemented with chia oil. CH supplementation enhanced A5D expressi Delta n whereas no significant differences between treatments were observed concerning A6D gene exp Delta ession. Activities of both desaturases were increased by including olive oil (OL + PCE and OL), and they were found to be higher in CH + PCE respect to CH for both enzymes. The ALA and n-3 LCPUFAs hepatic content was higher with CH, decreasing the levels of AA and n-6 LCPUFAs. It is concluded that the joint action of flavonoids such as anthocyanins and ALA show an antiadipogenic effect. Desaturase activity was inhibited by ALA and kept by the anthocyanins from PCE, thus anthocyanins would exert a protective effect on the desaturase activity but they would not affect on its gene expression, however, high doses of ALA increased the production of its metabolites, masking the effect of PCE.Secretaria de Eduacion Superior, Ciencia, Tecnologia e Innovacion (SENESCYT) from the Ecuadorian government 043-CEB - 201

Sardinian Boraginaceae are new potential sources of gamma-linolenic acid

© 2016 The aim of this work was to establish the richness in γ-linolenic acid (GLA, 18:3n6) and stearidonic acid (SDA, 18:4n3) of several Sardinian Boraginaceae species. To this end, seeds of selected species were collected from their natural habitats and analysed. The highest GLA contents were found in the seed oils of two endemic Borago taxa, i.e. B. morisiana (24.4 and 24.6% GLA of total fatty acids for samples from San Pietro Island and Sardinia Island, respectively), and 22.9% GLA for B. pygmaea. Both Borago species contained more GLA than B. officinalis collected in the same ecosystems. SDA was found in significant amounts in Echium plantagineum seed oil from the Lattias Mountains (15% SDA of total fatty acids). It is notable that both Borago GLA-rich species are under threat of extinction, thus revealing the importance of the preservation of the natural Sardinian ecosystems for endangered species and human health

Arecaceae Seeds Constitute a Healthy Source of Fatty Acids and Phenolic Compounds

Seeds of most Arecaceae species are an underutilized raw material that can constitute a source of nutritionally relevant compounds. In this work, seeds of 24 Arecaceae taxa were analyzed for fatty acids (FAs) by GC-FID, for phenolics by HPLC-DAD and LC-MS, and for their antitumor activity against the HT-29 colorectal cancer cell line by the MTT assay. Lauric, oleic, and linoleic acids were the prominent FAs. Cocoseae species contained total FAs at 28.0–68.3 g/100 g seeds, and in other species total FAs were from 1.2 (Livistona saribus) to 9.9 g/100 g (Washingtonia robusta). Sabal domingensis, Chamaerops humilis, and Phoenix dactylifera var. Medjool had unsaturated/saturated FA ratios of 1.65, 1.33–1.78, and 1.31, respectively, and contained 7.4, 5.5–6.3, and 6.4 g FAs/100 g seeds, respectively. Thus, they could be used as raw materials for healthy oilseed production. Phenolics ranged between 39 (Livistona fulva) and 246 mg/100 g (Sabal palmetto), and of these, caffeic acid, catechin, dactylifric acid, and rutin had the highest values. (-)-Epicatechin was identified in most seed extracts by LC-MS. Hydroalcoholic extracts from five species showed a dose-dependent inhibitory effect on HT-20 cells growth at 72 h (GI50 at 1533–1968 µg/mL). Overall, Arecaceae seeds could be considered as a cheap source of health-promoting compounds

Profile and distribution of fatty acids in edible parts of commonly consumed marine fishes in Chile

Fatty acid profiles and distribution among lipid classes in the edible parts of seven commonly consumed marine fishes in Chile were investigated. Peruvian morwong, Chilean jack mackerel and Pacific sandperch were found to be the richest sources of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) with 440.2, 343.7 and 313.9 mg EPA + DHA/100 g raw fillet respectively among the studied fishes. DHA was mainly found in the phospholipid fraction in all cases, following EPA the same trend except for Pacific sandperch, Chilean hake (most EPA in triacylglycerols) and Peruvian morwong (most EPA as free fatty acid). A very favorable n-3/n-6 PUFA ratio was found in all studied species, and PUFA/SFA ratios ranged between 0.94 and 1.72, which is desirable to keep a healthy cardiovascular status. This is the first study reporting fatty acid profiles and distribution of commonly consumed marine fishes in Chile

Vegetable oils rich in alpha linolenic acid incremen the paticn-3 LCPUFA, modulating the fatty acid metabolism and antioxidant response in rats

Alpha-linolenic acid (C18:3 n-3, ALA) is an essential fatty acid and the metabolic precursor of long-chain polyunsaturated fatty acids (LCPUFA) from the n-3 family with relevant physiological and metabolic roles: eicosapentaenoic acid (C20:5 n-3, EPA) and docosahexaenoic acid (C22:6 n-3, DHA). Western diet lacks of suitable intake of n-3 LCPUFA and there are recommendations to increase the dietary supply of such nutrients. Seed oils rich in ALA such as those from rosa mosqueta (Rosa rubiginosa), sacha inchi (Plukenetia volubis) and chia (Salvia hispanica) may constitute an alternative that merits research. This study evaluated hepatic and epididymal accretion and biosynthesis of n-3 LCPUFA, the activity and expression of Delta-5 and Delta-6 desaturase enzymes, the expression and DNA-binding activity of PPAR-alpha and SREBP-1c, oxidative stress parameters and the activity of antioxidative enzymes in rats fed sunflower oil (SFO, 1% ALA) as control group, canola oil (CO, 10% ALA), rosa mosqueta oil (RMO, 33% ALA), sacha inchi oil (SIO, 49% ALA) and chia oil (ChO, 64% ALA) as single lipid source. A larger supply of ALA increased the accretion of n-3 LCPUFA, the activity and expression of desaturases, the antioxidative status, the expression and DNA-binding of PPAR-alpha, the oxidation of fatty acids and the activity of antioxidant enzymes, whereas the expression and DNA-binding activity of SREBP-1c transcription factor and the biosynthetic activity of fatty acids declined. Results showed that oils rich in ALA such as SIO and ChO may trigger metabolic responses in rats such as those produced by n-3 PUFA. (C) 2016 Elsevier Ltd. All rights reserved