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51.
The 3% chitosan solutions incorporating 10% fish oil (w/w chitosan, containing 91.2% EPA and DHA) with or without the addition of 0.8% vitamin E were prepared. Fresh lingcod (Ophiodon elongates) fillets were vacuum-impregnated in coating solution at 100 mm Hg for 10 min followed by atmospheric restoration for 15 min, dried, and then stored at 2 °C or −20 °C for 3-weeks and 3-months, respectively, for physicochemical and microbial quality evaluation. Chitosan–fish oil coating increased total lipid and omega-3 fatty acid contents of fish by about 3-fold, reduced TBARS values in both fresh and frozen samples, and also decreased drip loss of frozen samples by 14.1–27.6%. Chitosan coatings resulted in 0.37–1.19 and 0.27–1.55 log CFU/g reductions in total plate and psychrotrophic counts in cold stored and frozen stored samples, respectively. Chitosan–fish oil coatings may be used to extend shelf-life and fortify omega-3 fatty acid in lean fish. 相似文献
52.
Siddabasave Gowda B. Gowda Takayuki Tsukui Hirotoshi Fuda Yusuke Minami Divyavani Gowda Hitoshi Chiba Shu-Ping Hui 《International journal of molecular sciences》2021,22(14)
Fatty acid esters of hydroxy fatty acids (FAHFAs) are a new class of endogenous lipids with interesting physiological functions in mammals. Despite their structural diversity and links with nuclear factor erythroid 2-related factor 2 (NRF2) biosynthesis, FAHFAs are less explored as NRF2 activators. Herein, we examined for the first time the synthetic docosahexaenoic acid esters of 12-hydroxy stearic acid (12-DHAHSA) or oleic acid (12-DHAHOA) against NRF2 activation in cultured human hepatoma-derived cells (C3A). The effect of DHA-derived FAHFAs on lipid metabolism was explored by the nontargeted lipidomic analysis using liquid chromatography-mass spectrometry. Furthermore, their action on lipid droplet (LD) oxidation was investigated by the fluorescence imaging technique. The DHA-derived FAHFAs showed less cytotoxicity compared to their native fatty acids and activated the NRF2 in a dose-dependent pattern. Treatment of 12-DHAHOA with C3A cells upregulated the cellular triacylglycerol levels by 17-fold compared to the untreated group. Fluorescence imaging analysis also revealed the suppression of the degree of LDs oxidation upon treatment with 12-DHAHSA. Overall, these results suggest that DHA-derived FAHFAs as novel and potent activators of NRF2 with plausible antioxidant function. 相似文献
53.
54.
DHA是一种重要的功能性ω-3多不饱和脂肪酸.我国卫生部相继批准了寇氏隐甲藻、裂壶藻、吾肯氏壶藻DHA藻油为新资源食品.收集并分析了9个商品化DHA藻油的脂肪酸含量,结合文献数据,发现通过商品化DHA藻油的脂肪酸特征推测其微藻属名是可行的.其中寇氏隐甲藻DHA藻油中长链多不饱和脂肪酸只含DHA,几乎不合DPA.裂壶藻与吾肯氏藻DHA藻油中长链多不饱脂肪酸主要以DHA和DPA为主,DHA/DPA比例随藻种而恒定,几乎不随发酵条件而有明显变化;DHA/DPA比例在2~3的DHA藻油多半来自裂壶藻;DHA/DPA比例在4~6的DHA藻油既可能来自裂壶藻也可能来自吾肯氏壶藻. 相似文献
55.
56.
57.
Michelle A. Phillips Caroline E. Childs Philip C. Calder Peter J. Rogers 《International journal of molecular sciences》2015,16(10):24600-24613
Findings from epidemiological and observational studies have indicated that diets high in omega-3 polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) may reduce the risk of cognitive decline and Alzheimer’s disease (AD). To determine if increasing intake of DHA and EPA through supplementation is beneficial to cognition and mood in individuals with cognitive impairment no dementia (CIND) or Alzheimer’s disease (AD) a four month, randomised, double-blind, placebo controlled study was conducted. Fifty-seven participants with CIND and nineteen with AD were randomised to receive either omega-3 PUFAs (600 mg EPA and 625 mg DHA per day) or placebo (olive oil) over a four month period. Elevating depleted levels of EPA and DHA through supplementation in individuals with CIND or AD was found to have negligible beneficial effect on their cognition or mood. These findings confirm an overall negligible benefit of omega-3 PUFA supplementation for those with cognitive impairment and dementia. More intervention studies need to be undertaken with longer study durations and larger sample sizes. It may prove fruitful to examine effects of different doses as well as effects in other dementia subtypes. 相似文献
58.
Water activity-adjusted enzymatic partial hydrolysis of phospholipids to concentrate polyunsaturated fatty acids 总被引:2,自引:0,他引:2
Masayo Ono Masashi Hosokawa Yoshikazu Inoue Koretaro Takahashi 《Journal of the American Oil Chemists' Society》1997,74(11):1415-1417
Selective partial hydrolyses of egg yolk phospholipid and squid skin phospholipid were carried out. By keeping the water activity
(a
w) of Lipozyme IM at an intermediate level, it was easy to concentrate docosahexaenoic acid (DHA). It was also possible to
concentrate both DHA and arachidonic acid (AA) simultaneously to a certain level under this a
w range. However, it was impossible to concentrate AA alone when DHA was present. Though there is a limitation in concentrating
AA exclusively, the proposed a
w-adjusted hydrolytic reaction is a promising way for preparing phospholipids rich in DHA. 相似文献
59.
Fayez?Hamam Fereidoon?ShahidiEmail author 《Journal of the American Oil Chemists' Society》2005,82(10):731-736
The lipase-assisted acidolysis of high-laurate canola oil (HLCO; Laurical 25) with long-chain n−3 FA (DHA and EPA) was studied.
Response surface methodology was used to obtain a maximal incorporation of DHA or EPA into HLCO. The studied process variables
were the amount of enzyme (2–6%), reaction temperature (35–55°C), and incubation time (12–36 h). The amount of water added
and the mole ratio of substrates (oil to DHA or EPA) were kept at 2% and 1∶3, respectively. All experiments were conducted
according to a face-centered cube design. Under optimal conditions (4.79% of enzyme; 46.1°C; 30.1 h), the incorporation of
DHA into HLCO was 37.3%. The corresponding maximal incorporation of EPA (61.6%) into Laurical 25 was obtained using 4.6% enzyme,
a reaction temperature of 39.9°C, and a reaction period of 26.2 h. Examination of the positional distribution of FA on the
glycerol backbone of modified HLCO with DHA showed that the DHA was primarily located in the sn-1,3 positions of the TAG molecules. However, lauric acid also remained mainly in the sn-1,3 positions of the modified oil. For EPA-modified Laurical 25, lauric acid was present mainly in the sn-1,3 positions, whereas EPA was randomly distributed over the three positions. 相似文献
60.
Docosahexaenoic Acid and Eicosapentaenoic Acid Did not Alter <Emphasis Type="Italic">trans</Emphasis>-10,<Emphasis Type="Italic">cis</Emphasis>-12 Conjugated Linoleic Acid Incorporation into Mice Brain and Eye Lipids
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Madhuri?Vemuri Yuriko?Adkins Bruce?E.?Mackey Darshan?S.?KelleyEmail author 《Lipids》2017,52(9):763-769
trans 10,cis 12‐CLA has been reported to alter fatty acid composition in several non‐neurological tissues, but its effects are less known in neurological tissues. Therefore, the purpose of this study was to determine if CLA supplementation would alter brain and eye fatty acid composition and if those changes could be prevented by concomitant supplementation with docosahexaenoic acid (DHA; 22:6n3) or eicosapentaenoic acid (EPA; 20:5n3). Eight‐week‐old, pathogen‐free C57BL/6N female mice (n = 6/group) were fed either the control diet or diets containing 0.5% (w/w) t10,c12‐CLA in the presence or absence of either 1.5% DHA or 1.5% EPA for 8 weeks. CLA concentration was significantly (P < 0.05) greater in the eye but not in the brain lipids of the CLA group when compared with the control group. The sums of saturated, monounsaturated, polyunsaturated fatty acids, and n3:n6 ratio did not differ between these two groups for both tissues. The n3:n6 ratio and concentrations of 20:5n3 and 22:5n3 were significantly greater, and those of 20:4n6, 22:4n6, and 22:5n6 were lesser in the CLA + DHA and CLA + EPA groups than in the control and CLA groups for either tissue. DHA concentration was higher in the CLA + DHA group only but not in the CLA + EPA group when compared with the CLA group for both tissues. The dietary fatty acids generally induced similar changes in brain and eye fatty acid concentration and at the concentrations used both DHA and EPA fed individually with CLA were more potent than CLA alone in altering the tissue fatty acid concentration. 相似文献