EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY
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2015
·Vol. 117
·期 12
·1928-1939
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IF 1.812
Junwei Lv,Xianqing Yang,Haixia Ma,Xiao Hu,Ya Wei,Wanjun Zhou,Laihao Li
The objective of this study was to examine the chemical composition and oxidative stability of microalgae oil, also to explore in vitro bioaccessibility and antioxidant activity of microalgae oil after simulated gastrointestinal digestion. In total, more than 50 fatty acids were identified by GC–MS analysis, with both palmitic acid (38.3%) and DHA (34.5%) being identified as major fatty acids. The contents of total phenolics and flavonoids in the various solvent extracts were measured spectrometrically, and their amounts were 39.33 ± 0.34 µg gallic acid/g and 16.08 ± 4.3 µg rutin/g, respectively. HPLC analysis showed that the contents of β-carotene, α-tocopherols, β- and γ-tocopherols (not separated) and δ-tocopherols were 136 µg/100 g, 164.4 µg/g, 317.3 µg/g, and 43.2 µg/g, respectively. Concerning sterols, cholesterol was the principal sterol at 4210.5 mg/kg and the other six main sterols were campesterol (121.4 mg/kg), 24-methylene cholesterol (192.8 mg/kg), 24-methyl-colest-7-en-3β-ol (144.6 mg/kg), ergosterol (144.8 mg/kg), stigmasterol (260.1 mg/kg) and Δ7,24-stigmastadienol (150.5 mg/kg), respectively. The overall chemical properties of the tested oils indicated that microalgae oil had a great oil quality. A Schaal oven test was used to evaluate the oxidative stability of microalgae oil. Furthermore, in vitro simulated gastrointestinal digestion was performed, and the antioxidant ability of digestion oil was determined by using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay, a 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cation decolourisation activity assay, a reducing power assay, a β-carotene bleaching assay and an oxygen radical absorbance capacity (ORAC) antioxidant assay. The results showed that following simulated gastrointestinal digestion, microalgae oil displayed a good in vitro bioaccessibility and moderate antioxidant capacity. Thus, the antioxidant activity of the microalgae oil was mainly contributed by its abundant antioxidant constituents. Practical applications: Schizochytrium aggregatum oil is a good source of DHA and of effective, bioaccessible antioxidants. The DPPH radical is rather stable, and our study used a relatively fast method for measuring both the hydrophilic and lipophilic substances during in vitro antioxidant activity. The change of violet colour to yellow during the DPPH assay is thought to be due to the attribution of hydrogen atoms by antioxidant substances. The extent of decolourisation is a significant indicator of the sample's antioxidant ability. As shown in figure that the scavenging abilities of all the samples were well correlated with increasing concentrations, and the scavenging activity of BHT was higher than that of microalgae oil. At concentrations ranging from 0.5 to 10 mg/mL, the DPPH radical scavenging ability of digestion oil was determined at 6.8–64.9%. Lower IC 50 values indicated a higher radical scavenging activity. The IC 50 value of microalgae oil in our DPPH radical scavenging study was 5.76 mg/mL, and solutions of BHT had an IC 50 value of 0.56 mg/mL. Although microalgae oil was shown to be weaker than BHT, it demonstrated a fairly good scavenging ability. The DPPH radical scavenging abilities of digestion oil and BHT.
研究领域:
食品科学
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营养学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2020
·
IF 6.146
Arif Ali,Chen Zhao
The processing of an energy carrier such as microalgae oil into valuable fuels and chemicals is quite promising. Aqueous-phase processing is suitable for this purpose because the separation of intrinsic water from the algae cell is difficult. In this study, we synthesized ruthenium (Ru) nanoparticles supported on highly hydrophilic mesoporous carbon to catalyze the quantitative hydrodeoxygenation (HDO) of microalgae oil to alkanes in a one-pot process at a low temperature (140 °C) in the aqueous phase. The mesoporous carbon was obtained by single-step calcination of starch and zinc chloride in nitrogen. The as-obtained carbon showed high surface areas and pore volumes, allowing high dispersion of Ru nanoparticles. The surface of the carbon material was rich in hydroxyl groups, as evidenced by X-ray photoelectron spectroscopy (XPS), infrared (IR) spectroscopy, and thermogravimetric analysis (TGA) measurements. As a result, the carbon material contacted preferably with the water phase versus the organic phase, improving the accessibility of substrates. On the other hand, the contact angle test results speculated the superior hydrophilic nature of mesoporous Ru/C (ZnCl 2 , starch) than commercial Ru/C. Both kinetics modeling and in situ IR monitoring in water revealed the superior performance of the hydrophilic mesoporous and hydrophilic Ru/C compared to a commercial Ru/C for the tandem hydrogenation of stearic acid and decarbonylation of stearyl alcohol. The herein designed hydrothermal carbon material was highly active, environmentally benign, sustainable, and recyclable material, and could be potentially used for other hydrogenation reactions in the aqueous phase.
研究领域:
催化化学
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可再生能源
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Biomass Conversion and Biorefinery
·
2024
·
IF 3.5
He Taotao,Wang Fei,Feng Junfeng,Liu Yancong,Chen Yuwei,Guo Feihong,Liu Peng,Jiang Xiaoxiang,Jiang Jianchun
To efficiently convert the microalgae to valuable and renewable fuels, the microalgae oil was first extracted and then transformed into the second-generation biodiesel. Among all solvents that were used for the microalgae oil extraction, the polar single solvent system methanol achieved the optimal value (47.8% extraction yield) because the polar cell membrane was easily dissolved by the polar solvent. Hexadecanoic acid (38.54%) and docosanoic acid (54.39%) dominated in fatty acid of microalgae oil. In the catalytic deoxygenation of microalgae oil, the Co-Al nanosheet displayed a higher performance than Co/Al 2 O 3 because of its high Co content and lamellar structure, exposing massive Co sites with high dispersion and small particle size. Moreover, when the reaction temperature was raised to 240 °C, the 100% conversion and 100% alkane yield were obtained, and the further temperature rise in temperature led to the cracking reaction. Graphical Abstract
研究领域:
生物能源
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化学工程
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环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN COLLEGE OF NUTRITION
·
2017
·
IF 2.107
Jinhui Yu,Yong Ma,Jie Sun,Liyuan Ran,Youwei Li,Ning Wang,Tao Yu,Wenting Gao,Wenbin Jia,Rujiao Jiang,Meihua Guo,Yuping Bi,Yingjie Wu
Objective: Dietary n-3 polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acids (EPA) and docosahexaenoic acid (DHA), are proved to be effective in obesity reduction. Microalgal oil (MO) is an important alternative source of n-3 PUFAs that effectively alleviates obesity. The aim of the present study was to explore the anti-obesity effects of microalgal oil from Schizochytrium sp. (SMO) and to compare the effects of 2 SMOs (SMO1 and SMO2) with different levels of purity of n-3 PUFAs on high fat diet (HFD)-induced obesity in male C57BL/6J mice.Methods: Mice were randomly divided into 5 groups: (1) regular chow (RC); (2) HFD; (3) HFD + fish oil (FO); (4) HFD + SMO1; and (5) HFD + SMO2. Body weight and food intake were weekly monitored. After 16 weeks of treatment, a glucose tolerance test (GTT) and an insulin tolerance test (ITT) were performed. Serum lipid profile, morphological changes in the liver and epididymal white adipose tissue (eWAT), and the mRNA expression of lipid metabolism–related genes were also examined.Results: SMO treatment significantly decreased HFD-induced abdominal fat accumulation, lowered the levels of triglycerides, cholesterol, and low-density lipoprotein, as did the positive control treated with FO. Morphological examination revealed a remarkable reduction in lipid droplet formation in the liver tissue and the particle size of eWAT. An alleviation of inflammation infiltration in eWAT caused by a high-fat diet was also observed. Real-time reverse transcription–polymerase chain reaction analysis examination confirmed that microalgal oil inhibited the gene expression of fatty acid synthase, sterol responsive element-binding protein-1c, and acetyl-CoA carboxylase but promoted that of hormone-sensitive lipase and lipoprotein lipase, carnitine palmitoyltransferase-1, and uncoupling proteins in the liver and eWAT. Moreover, similar anti-obesity effects were obtained with the same dosage but different purity of n-3 PUFAs.Conclusions: As an alternative n-3 PUFAs resource, dietary intake of SMO might be beneficial to prevent HFD-induced abdominal fat accumulation.
研究领域:
营养学
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肥胖研究
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分子生物学
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脂质代谢
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food & Function
·
2022
·Vol. 13
·期 24
·12799-12813
·
IF 6.317
Liyuan Ran,Jinhui Yu,Rui Ma,Qing Yao,Mingjie Wang,Yuping Bi,Zichao Yu,Yingjie Wu
Omega-3 PUFAs rich in fish oil are believed to prevent obesity by improving lipid metabolism and regulating gut microbiota. Microalgae oil is considered as an alternative source of omega-3 PUFAs owing to diminishing fish resources. Schizochytrium microalgae oil (SMO), with a high DHA proportion, is a promising source for commercial DHA production. However, its weight-loss and gut microbiota-regulating properties are not well studied. Here we compared the obesity reducing effects of SMO, commercial fish oil (FO) and a weight-loss drug, Orlistat (OL), in a high-fat diet (HFD) induced obesity mouse model. We found that SMO is comparable to commercial FO and OL with regard to weight loss, and it even exhibits the weight-loss effects earlier than FO and OL. It can efficiently inhibit the expression of lipogenesis-related genes and induce the expression of lipolysis-related genes. Moreover, SMO has different gut microbiota modulating effects from those of FO and OL. It does not influence the diversity of bacterial community, but does increase the abundance of several beneficial SCFAs-producing bacteria and inhibits obesity-promoting Desulfovibrio and several pathogens. We also found that SMO recovers the HFD-disturbed metabolic capability of gut microbiota. It can increase the abundance of several metabolism-related pathways, such as those of amino acids, SCFAs and bile acid, and decrease the level of the LPS biosynthesis pathway, which probably contributes to an improvement of lipid metabolism and restoration of the colonic mucosal barrier impaired by HFD. Our data suggest that SMO can be used as a superior dietary supplement for alleviating obesity.
研究领域:
营养学
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微生物学
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代谢学
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药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FITOTERAPIA
·
2021
·
IF 2.882
Rui Zha,Enhui Ge,Lirong Guo,Qing Gao,Qiqi Lin,Wan Zhou,Xiaobao Jin,Weiquan Xie,Hui Yin,Tao Liu
Macamides are a class of bioactive amide alkaloids found only in maca ( Lepidium meyenii ). Recent studies have shown that macamide-rich extracts possess various biological activities , such as antioxidative, immune-enhancing, and reproductive health-improving activities. In the present study, N-benzyl docosahexaenamide (NB-DHA), a newly identified macamide with the highest degree of unsaturation among all identified macamides, was identified from the maca extract. Microalgae oil, a docosahexaenoic acid-rich substance, was used as the starting material for the synthesis of NB-DHA. The effects of NB-DHA in colitis-induced mice were evaluated. NB-DHA significantly alleviated weight loss, shortening of colon length, and occult blood occurrence in mice with dextran sulfate sodium-induced colitis . Histological analysis revealed that following the administration of NB-DHA in mice with colitis, the infiltration of inflammatory cells and levels of proinflammatory factors, such as tumor necrosis factor-α, interleukin (IL)-1β, IL-6, and myeloperoxidase , decreased, whereas the level of the anti-inflammatory factor IL-10 increased. Furthermore, the decreased expression of intestinal tight junction proteins caused by colitis was upregulated by the administration of NB-DHA. These results indicate that NB-DHA could be developed as a therapeutic agent for ulcerative colitis .
研究领域:
药理学
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免疫学
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胃肠病学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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