Stanols

甾烷醇
  • 文章类型: Journal Article
    青藏高原(TP)由于其极端的居住环境,是人类长期定居最具挑战性的地区之一。了解这种极端环境中人类活动与环境变化的关系具有重要意义,可以为适应未来气候变化提供历史参考。在这项研究中,我们以TP南部的安格伦盆地为例,阐明了自小冰河时代(LIA)以来的关系。在粪便中使用粪便甾烷醇,湖泊和河流表面沉积物,表层土壤,和沉积物核心,我们发现,具体指标S1和S2的成分,表前列腺素,5β-乙基前列腺素和5β-乙基吡啶前列腺素可以反映人口和草食动物的变化,分别。通过比较由晶粒尺寸决定的环境变化,元素,沉降速率,和其他气候记录,解释了人类活动与环境变化之间的关系。我们的结果表明:(I)公元1480-1820年,湖泊沉积物中的粪便甾烷主要来自牲畜,人口很少。相比之下,在1820-2021年的CE,S1的比例和通量一直在不断增加,表明人口显著增长。(ii)在LIA中间,寒冷干燥的气候抑制了农业和农业的发展。然而,LIA后期降水的增加促进了这种发展,导致人口和牲畜在短期内增加。(三)1951年以来,人们开荒,发展畜牧业,导致土壤侵蚀增加。(四)过去40年,在温暖潮湿的气候和良好的政策支持下,人类活动,如农业和畜牧业,迅速增加,但是由于良好的水土保持努力,土壤侵蚀在最近20年有所下降。这项研究揭示了人类活动与环境变化之间的关系,并为未来的气候变化响应提供了见解。
    The Tibetan Plateau (TP) is one of the most challenging areas for human long-term settlement due to its extreme living environment. Understanding the relationship between human activities and environmental changes in this extreme environment is important and can provide a historical reference for adapting to future climate change. In this study, we took the Angren Basin in the southern TP as a case study to elucidate the relationship since Little Ice Age (LIA). Using fecal stanol in feces, lake and river surface sediments, surface soils, and sediment core, we found that specific indices S1 and S2 from the composition of coprostanol, epicoprostanol, 5β-ethylcoprostanol and 5β-ethylepicoprostanol can reflect changes in human population and herbivores, respectively. Through the comparison between environmental changes determined by grain size, elements, sedimentation rate, and other climate records, the relationship between human activities and environmental changes was interpreted. Our results indicate that: (i) during 1480-1820 CE, the fecal stanols in lake sediments mainly originated from livestock, and the human population was low. In contrast, during 1820-2021 CE, the proportion and flux of S1 have been continuously increasing, indicating significant population growth. (ii) During the middle LIA, the cold-dry climate inhibited the development of agriculture and farming. However, the increased precipitation during the late LIA promoted that development, resulting in an increase in human population and livestock in a short term. (iii) Since 1951, people have reclaimed wasteland and developed husbandry, leading to increased soil erosion. (iv) Over the past 40 years, with a warm-humid climate and good policy support, human activities, such as agriculture and husbandry, have rapidly increased, but soil erosion has declined in the recent 20 years due to good soil-water conservation efforts. This study sheds light on the relationship between human activities and environmental changes and provides insights into future climate change responses.
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  • 文章类型: Journal Article
    茄子油炸期间使用鳄梨初榨油(AVO),沸腾,并在水-油混合物(W/O)中沸腾。测量了水分含量,干物质,脂肪,总(TPC)和十种单独的酚,抗氧化活性(ABTS和DPPH),和总甾醇;以及八种脂肪酸和十四种甾醇/甾烷醇的概况。用多变量分析对原料和加工食品的价值进行了比较和研究。深炸后AVO的抗氧化能力降低,但在所有处理后的茄子和水中,AVO的抗氧化能力增强。TPC在AVO中稳定,在油炸茄子中升高。热处理添加到AVO的初始轮廓,茄子和水,九,八,和四种酚,分别。主要脂肪酸(油酸,棕榈酸和亚油酸),和甾醇(β-谷甾醇,菜油甾醇,和Δ5-avenasterol),在原始AVO和处理过的AVO之间保持不变;以及来自加工茄子的脂质部分。烹饪导致亲水性和亲脂性功能化合物在AVO之间移动,茄子和水。在油炸和W/O煮沸过程中,甾醇和不饱和脂肪酸从AVO迁移到茄子中,通过将高生物学价值的亲脂性部分添加到天然存在的多酚中,改善了茄子的功能特性。
    Avocado virgin oil (AVO) was used during eggplant deep-frying, boil, and boil in a water-oil mixture (W/O). There were measured the contents of moisture, dry matter, fat, total (TPC) and ten individual phenols, antioxidant activity (ABTS and DPPH), and total sterols; as well as the profiles of eight fatty acids and fourteen sterols/stanols. The values of raw and processed foods were compared and studied with multivariate analysis. The antioxidant capacity of AVO lowered after deep frying but augmented in eggplant and water after all treatments. The TPC was steady in AVO and raised in fried eggplant. Thermal treatments added to the initial profiles of the AVO, eggplant and water, nine, eight, and four phenols, respectively. Percentages of the main fatty acids (oleic, palmitic and linoleic), and sterols (β-sitosterol, campesterol, and Δ5-avenasterol), remained unchanged between the raw and treated AVO; and the lipidic fractions from processed eggplant. Cooking leads to the movement of hydrophilic and lipophilic functional compounds between AVO, eggplant and water. Migration of sterols and unsaturated fatty acids from AVO to eggplant during deep frying and W/O boiling improved the functional properties of eggplant by adding the high biological value lipophilic fraction to the naturally occurring polyphenols.
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  • 文章类型: Journal Article
    BACKGROUND: Although a cholesterol-lowering diet and the addition of plant sterols and stanols are suggested for the lipid management of children and adults with familial hypercholesterolemia, there is limited evidence evaluating such interventions in this population.
    OBJECTIVE: To investigate the impact of cholesterol-lowering diet and other dietary interventions on the incidence or mortality of cardiovascular disease and lipid profile of patients with familial hypercholesterolemia.
    METHODS: Relevant trials were identified by searching US National Library of Medicine National Institutes of Health Metabolism Trials Register and clinicaltrials.gov.gr using the following terms: diet, dietary, plant sterols, stanols, omega-3 fatty acids, fiber and familial hypercholesterolemia.
    METHODS: Randomized controlled trials evaluating the effect of cholesterol-lowering diet or other dietary interventions in children and adults with familial hypercholesterolemia were included.
    METHODS: Two authors independently assessed the eligibility of the included trials and their bias risk and extracted the data which was independently verified by other colleagues.
    RESULTS: A total of 17 trials were finally included, with a total of 376 participants across 8 comparison groups. The included trials had either a low or unclear bias risk for most of the assessed risk parameters. Cardiovascular incidence or mortality were not evaluated in any of the included trials. Among the planned comparisons regarding patients\' lipidemic profile, a significant difference was noticed for the following comparisons and outcomes: omega-3 fatty acids reduced triglycerides (mean difference (MD): -0.27 mmol/L, 95% confidence interval (CI): -0.47 to -0.07, p < 0.01) when compared with placebo. A non-significant trend towards a reduction in subjects\' total cholesterol (MD: -0.34, 95% CI: -0.68 to 0, mmol/L, p = 0.05) and low-density lipoprotein cholesterol (MD: -0.31, 95% CI: -0.61 to 0, mmol/L, p = 0.05) was noticed. In comparison with cholesterol-lowering diet, the additional consumption of plant stanols decreased total cholesterol (MD: -0.62 mmol/L, 95% CI: -1.13 to -0.11, p = 0.02) and low-density lipoprotein cholesterol (MD: -0.58 mmol/L, 95% CI: -1.08 to -0.09, p = 0.02). The same was by plant sterols (MD: -0.46 mmol/L, 95% CI: -0.76 to -0.17, p < 0.01 for cholesterol and MD: -0.45 mmol/L, 95% CI: -0.74 to -0.16, p < 0.01 for low-density lipoprotein cholesterol). No heterogeneity was noticed among the studies included in these analyses.
    CONCLUSIONS: Available trials confirm that the addition of plant sterols or stanols has a cholesterol-lowering effect on such individuals. On the other hand, supplementation with omega-3 fatty acids effectively reduces triglycerides and might have a role in lowering the cholesterol of patients with familial hypercholesterolemia. Additional studies are needed to investigate the efficacy of cholesterol-lowering diet or the addition of soya protein and dietary fibers to a cholesterol-lowering diet in patients with familial hypercholesterolemia.
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  • 文章类型: Journal Article
    The methanolic extract of the waste seeds of Sesamum indicum L. (Pedaliaceae) was subjected to chromatographic fractionation; it led to the isolation of an alkyl benzene identified as 1,3-bis (pentadecyl)benzene (1) along with three known fatty acids: oleic acid (2), linoleic acid (3), and palmitic acid (4); one monosaturated cardanol, 3-pentadecylphenol (5) and two phytosteroids identified as sitostanol (6) and campestanol (7). The structures of these compounds were elucidated by chemical and spectroscopic analyses. Compounds 1, 5 and 6 were evaluated against protozoan parasites. Compound 1 moderately inhibited the promastigote form of Leishmania donovani LG13 with IC50 equal to 16.9 μM.
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  • 文章类型: Journal Article
    In intensive livestock areas, veterinary pharmaceutical residues (VPRs) can occur in water resources, but also in tap water because treatment processes are not designed to remove these contaminants. The main objective of this study is to assess the occurrence of VPRs in water resources and tap waters in Brittany. As several identical compounds are used in both veterinary and human medicine, a toolbox (stanols and pharmaceuticals) is used to help determine the origin of contamination in the case of mixed-use molecules. Water resources samples were collected from 25 sites (23 surface waters and two groundwaters) used for tap water production and located in watersheds considered as sensitive due to intensive husbandry activities. Samples were also taken at 23 corresponding tap water sites. A list of 38 VPRs of interest was analyzed. In water resources, at least one VPR was quantified in 32% of the samples. 17 different VPRs were quantified, including antibiotics, antiparasitic drugs and anti-inflammatory drugs. Concentration levels ranged between 5 ng/L and 2946 ng/L. Mixed-use pharmaceuticals were quantified in twelve samples of water resources and among these samples nine had a mixed overall fecal contamination. In the context of this large-scale study, it appeared difficult to determine precisely the factors impacting the occurrence of VPRs. VPRs were quantified in 20% of the tap water samples. Twelve VPRs were quantified, including ten compounds exclusively used in veterinary medicine and two mixed-use compounds. Concentration levels are inferior to 40 ng/L for all compounds, with the exception of the antibiotic florfenicol which was quantified at 159 ng/L and 211 ng/L. The population of Brittany may therefore be exposed to these contaminants through tap water. These observations should be put into perspective with the detection frequencies per compound which are all below 10% in both water resources and tap water.
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  • 文章类型: Journal Article
    With the expansion of urban centres in the mid-twentieth century and the post-1970 decrease in pesticides, populations of double-crested cormorants (Phalacrocorax auritus) and ring-billed gulls (Larus delawarensis) around Lake Ontario (Canada and USA) have rapidly rebounded, possibly to unprecedented numbers. Along with the use of traditional palaeolimnological methods (e.g. stable isotopes, biological proxies), we now have the capacity to develop specific markers for directly tracking the presence of waterbirds on nesting islands. Here, we apply the use of lipophilic sterols and stanols from both plant and animal-faecal origins as a reliable technique, independent of traditional isotopic methods, for pinpointing waterbird arrival and population growth over decadal timescales. Sterol and stanol concentrations measured in the guano samples of waterbird species were highly variable within a species and between the three species of waterbirds examined. However, cholesterol was the dominant sterol in guano, and phytosterols were also high in ring-billed gull guano. This variability highlights a specialist piscivorous diet for cormorants compared to a generalist, omnivorous diet for gulls, which may now often include grain and invertebrates from agricultural fields. A ratio that includes cholesterol and sitosterol plus their aerobically reduced products (cholestanol, stigmastanol) best explained the present range of bird abundance across the islands and was significantly correlated to sedimentary δ15N. Overall, we demonstrate the use of sterols and stanols as a direct means for tracking the spatial and temporal presence of waterbirds on islands across Lake Ontario, and probably elsewhere.
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  • 文章类型: Comparative Study
    The presented work describes the development and validation of a rapid UHPLC-UV/CAD method using a core-shell particle column for the separation and quantitative analysis of seven plant sterols and stanols. The phytosterols (ergosterol, brassicasterol, campesterol, fucosterol, stigmasterol, and β-sitosterol) and the phytostanol stigmastanol were separated and analyzed in 8.5min. The sample pre-treatment procedure was optimized to be less time-consuming than any other published method, especially due to no need of derivatization, evaporation and even reconstitution step. The chromatographic separation was performed on the Kinetex 1.7μ Phenyl-hexyl column (100×2.1mm) with a mobile phase acetonitrile/water according to the gradient program at a flow rate of 0.9mLmin-1 and a temperature of 60°C. A tandem connection of PDA and CAD (Corona Charged Aerosol Detector) was used and both detection techniques were compared. The method was validated using saponification as a first step in sample pre-treatment and an universal CAD as the detector. Recoveries for all analyzed compounds were between 95.4% and 103.4% and relative standard deviation ranged from 1.0% to 5.8% for within-day and from 1.4% to 6.7% for between-day repeatability. The limits of detection were in the range of 0.4-0.6μgmL-1 for standard solutions and 0.3-1.2μgmL-1 for phytosterols in real samples. Although several gradient programs and different stationary phases were tested, two compounds, campesterol and campestanol, were not separated. Their peak was quantified as a sum of both analytes.
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  • 文章类型: Journal Article
    The prevalence of premature atherosclerosis and cardiovascular disease (CVD) is constantly increasing worldwide. It has been proved that LDL-cholesterol (LDL-C) plays causal role in the development of coronary atherosclerosis. The fact that atherosclerosis is a chronic and progressive disease which onsets during the first three decades of life bores questions what to do to maintain LDL-C at low levels throughout life and thus to delay and/or prevent the progress this disease. Currently, most of public health expenses are spared on treatment, but not on prophylaxis.
    This is a review article summarizing novel reports concerning the efficacy of sterols/stanols as lipidlowering agents, assessing their influence on cardiovascular risk and safety.
    It has been suggested that sterols and stanols are effective in the lowering of low-density cholesterol levels and diminishing cardiovascular risk. However, the results of other studies suggest that phytosterols may not exert positive effects during atherogenesis. Firstly, patients with phytosterolaemia (genetic disease in which high plant sterol plasma concentrations are observed) develop malignant premature atherosclerosis. Moreover, several epidemiological studies demonstrated the association between upper normal plasma concentrations of plant sterols and increased risk of cardiovascular events. Finally, the supplementation with plant stanols and plant sterols may be not beneficial due to their incorporation in various tissues and potentially resulting in adverse effects.
    Despite the worldwide promotion of sterols as health improving supplements, it seems that in some people responding with relatively high phytosterol serum levels after its consumption such additives may turn out to be as good as it has been believed.
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  • 文章类型: Journal Article
    OBJECTIVE: Regular intake of phytosterols (PS) is proven to dose-dependently lower LDL-cholesterol (LDL-C). Whether PS consumption can also impact low-grade inflammation is unclear. Considering the low feasibility of outcomes studies involving PS consumption, investigation of surrogate markers of atherosclerosis represents a valuable approach. This study assessed the anti-inflammatory effect of PS consumption, according to inflammatory biomarkers, mainly C-reactive protein (CRP).
    RESULTS: A systematic search of Medline, Cab Abstracts, and Food Science & Technology Abstracts was conducted through January 2015. Our study selection included randomized controlled trials (RCT), involving intake of PS-enriched foods as active treatment, and measurement of plasma inflammatory biomarkers. Random-effects meta-analyses were performed using average baseline and end-of-intervention concentrations and control-adjusted absolute changes in CRP and blood lipids. There were 20 eligible RCTs including a total of 1308 subjects. The absolute change of plasma CRP levels with PS consumption was -0.10 mg/L (95%CI -0.26; 0.05), a non-significant change, and heterogeneity had borderline significance (I(2) = 29.1; p-value = 0.073). The absolute reduction of LDL-C was -14.3 mg/dL (95%CI -17.3; -11.3). Meta-regression analyses showed that both the dose and duration of PS intake significantly influenced the absolute changes in plasma CRP (β = -0.35, p = 0.0255 and β = -0.03, p = 0.0209, respectively).
    CONCLUSIONS: In this meta-analysis, regular intake of PS-enriched foods did not significantly change CRP, whilst LDL-C concentrations were significantly reduced. Further studies with higher PS doses may provide more definite conclusions on a potential anti-inflammatory effect of PS intake.
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  • 文章类型: Journal Article
    In this study, (1)H Nuclear Magnetic Resonance was used to monitor the evolution of three margarines of varied compositions when submitted to heating at 180°C in an oven with aeration. Heating causes degradation of polyunsaturated acyl groups and this depends not only on their unsaturation degree, but also on the concentration of the different acyl groups. The evolution of monounsaturated groups varies depending on the disappearance rate of the groups with higher unsaturation degree. Heat treatment also causes hydrolysis reactions that lead to a reduction in 1-monoglycerides and an increase in 1,2-diglycerides, especially in the margarines with higher water content, as well as degradation of some vegetable sterols. Different types of aldehydes and epoxides were identified and quantified, above all in the margarine with the highest proportion of polyunsaturated groups, especially linoleic; some of these are toxic, such as 4-hydroxy- and 4,5-epoxy-2-alkenals.
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