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Biochimica Et Biophysica Acta Feb 2013Sugars are recognized as signaling molecules regulating the biosynthesis of secondary metabolites in plants. Here, a modulatory effect of sugars on dolichol and...
Sugars are recognized as signaling molecules regulating the biosynthesis of secondary metabolites in plants. Here, a modulatory effect of sugars on dolichol and phytosterol profiles was noted in the hairy roots of Arabidopsis thaliana. Arabidopsis roots contain a complex dolichol mixture comprising three groups ('families') of dolichols differing in the chain-length. These dolichols, especially the longest ones are accompanied by considerable amounts of polyprenols of the same length. The spectrum of polyisoprenoid alcohols, i.e. dolichols and polyprenols, was dependent on sugar type (glucose or sucrose) and its concentration in the medium. Among the long-chain dolichols Dol/Pren-20 (dolichol or prenol molecule composed of 20 isoprene residues) and Dol/Pren-23 were the main components at 0.5% and 2% glucose, respectively. Moreover, the ratio of polyprenols versus respective dolichols was also modulated by sugar in this group of polyisoprenoids, with polyprenols dominating at 3% sucrose and dolichols at 2% glucose. Glucose concentration affected the expression level of genes encoding cis-prenyltransferases, enzymes responsible for elongation of the polyisoprenoid chain. The most abundant phytosterols of the A. thaliana roots, β-sitosterol, stigmasterol and campesterol, were accompanied by corresponding stanols and traces of brassicasterol, stigmast-4,22-dien-3-one and stigmast-4-en-3-one. Similar to the polyisoprenoids, sterol profile responded to the sugar present in the medium, β-sitosterol dominating in roots grown on 3% or lower glucose concentrations and stigmasterol in 3% sucrose. These results indicate an involvement of sugar signaling in the regulation of cis-prenyltransferases and phytosterol pathway enzymes.
Topics: Arabidopsis; Biological Availability; Carbohydrate Metabolism; Phytosterols; Plant Roots; Terpenes
PubMed: 23178167
DOI: 10.1016/j.bbalip.2012.11.006 -
Journal of Oleo Science Feb 2022Baru (Dipteryx alata) almond is an emerging nut from the Brazilian savannah, that presents unique flavor and an interesting specialty oil. In this study, we aimed at...
Baru (Dipteryx alata) almond is an emerging nut from the Brazilian savannah, that presents unique flavor and an interesting specialty oil. In this study, we aimed at investigating the effects of pressure, temperature, type (alcohol and/or water), and concentration of polar cosolvent on the extraction yield and tocopherol contents of baru oil obtained by supercritical-CO extraction (SC-CO); and to investigate the effect of temperature and pressure on phytosterol, phenolic, and volatile compounds' profile in the oil when HO was the cosolvent. Baru oil extracted with SC-CO using alcohol as a cosolvent showed a higher extraction yield (20.5-31.1%) than when using HO (4.16-22.7%). However, when 0.3% HO was used as cosolvent, baru oils presented the highest γ-tocopherol (107 and 43.7 mg/100 g) and total tocopherol (212 and 48.7 mg/100 g) contents, depending on the temperature and pressure used (50°C and 10 MPa or 70°C and 30 MPa, respectively). Consequently, the lowest pressure (10 MPa) and temperature (50°C) values resulted in baru oils with better γ/α-ratio, and the highest contents of β-sitosterol (107 mg/100 g) and phenolic compounds (166 mg/100 g). However, the highest pressure (30 MPa) and temperature (70°C) values improved the volatile profile of oils. Therefore, although alcohol as a cosolvent improved oil yield, small amounts of HO provided a value-added baru oil with either high content of bioactive compounds or with a distinctive volatile profile by tuning temperature and pressure used during SC-CO extraction.
Topics: Alcohols; Carbon Dioxide; Dipteryx; Hydroxybenzoates; Liquid-Liquid Extraction; Phytosterols; Plant Oils; Pressure; Solvents; Temperature; Tocopherols; Volatile Organic Compounds; Water
PubMed: 35034941
DOI: 10.5650/jos.ess21115 -
Molecules (Basel, Switzerland) Nov 2022Concerns have been raised about the safety and tolerability of phytosterol esters due to their vulnerability to oxidation. Herein, oxidation of the unsaturated fatty...
Concerns have been raised about the safety and tolerability of phytosterol esters due to their vulnerability to oxidation. Herein, oxidation of the unsaturated fatty acid-phytosterol ester, namely β-sitosteryl oleate, was observed in comparison to native β-sitosterol after accelerated storage at 65 °C for 35 days in a bulk oil model system. Depending on the sterol structure, various chemical indices of lipid oxidation, including hydroperoxide value (HPV), thiobarbituric acid reactive substances (TBARS), -anisidine value (AnV), and 7-keto derivatives, changed at varying rates in both samples. Such indicators for β-sitosteryl oleate appeared to be obtained at higher concentrations than those for β-sitosterol. The first order kinetic was used to describe the losses of β-sitosteryl oleate and β-sitosterol in bulk oil. It was discovered that the β-sitosteryl oleate (k = 0.0202 day) underwent oxidative alteration more rapidly than β-sitosterol (k = 0.0099 day). Results indicated that physical structure was the principal factor in the determination of storage stability of phytosterol and its ester. Research on antioxidants and storage techniques can be expanded in order to reduce the oxidative loss of phytosterol esters during storage and improve the safety and tolerability of phytosterol esters.
Topics: Oleic Acid; Kinetics; Oxidation-Reduction; Phytosterols; Fatty Acids; Esters
PubMed: 36431934
DOI: 10.3390/molecules27227833 -
PloS One 2015Dietary phytosterols, plant sterols structurally similar to cholesterol, reduce intestinal cholesterol absorption and have many other potentially beneficial biological... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Dietary phytosterols, plant sterols structurally similar to cholesterol, reduce intestinal cholesterol absorption and have many other potentially beneficial biological effects in humans. Due to limited information on phytosterol levels in foods, however, it is difficult to quantify habitual dietary phytosterol intake (DPI). Therefore, we sought to identify a plasma biomarker of DPI.
METHODS AND FINDINGS
Data were analyzed from two feeding studies with a total of 38 subjects during 94 dietary periods. DPI was carefully controlled at low, intermediate, and high levels. Plasma levels of phytosterols and cholesterol metabolites were assessed at the end of each diet period. Based on simple ordinary least squares regression analysis, the best biomarker for DPI was the ratio of plasma campesterol to the endogenous cholesterol metabolite 5-α-cholestanol (R2 = 0.785, P < 0.0001). Plasma campesterol and 5-α-cholestanol levels varied greatly among subjects at the same DPI level, but were positively correlated at each DPI level in both studies (r > 0.600; P < 0.01).
CONCLUSION
The ratio of plasma campesterol to the coordinately regulated endogenous cholesterol metabolite 5-α-cholestanol is a biomarker of dietary phytosterol intake. Conversely, plasma phytosterol levels alone are not ideal biomarkers of DPI because they are confounded by large inter-individual variation in absorption and turnover of non-cholesterol sterols. Further work is needed to assess the relation between non-cholesterol sterol metabolism and associated cholesterol transport in the genesis of coronary heart disease.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biomarkers; Cholestanol; Cholesterol; Diet; Female; Humans; Male; Middle Aged; Phytosterols; Young Adult
PubMed: 25668184
DOI: 10.1371/journal.pone.0116912 -
European Journal of Nutrition Nov 2019Evidence exists regarding the beneficial effects of diets rich in plant-based foods regarding the prevention of cardiometabolic diseases. These plant-based foods are an... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Evidence exists regarding the beneficial effects of diets rich in plant-based foods regarding the prevention of cardiometabolic diseases. These plant-based foods are an exclusive and abundant source of a variety of biologically active phytochemicals, including polyphenols, carotenoids, glucosinolates and phytosterols, with known health-promoting effects through a wide range of biological activities, such as improvements in endothelial function, platelet function, blood pressure, blood lipid profile and insulin sensitivity. We know that an individual's physical/genetic makeup may influence their response to a dietary intervention, and thereby may influence the benefit/risk associated with consumption of a particular dietary constituent. This inter-individual variation in responsiveness has also been described for dietary plant bioactives but has not been explored in depth. To address this issue, the European scientific experts involved in the COST Action POSITIVe systematically analyzed data from published studies to assess the inter-individual variation in selected clinical biomarkers associated with cardiometabolic risk, in response to the consumption of plant-based bioactives (poly)phenols and phytosterols. The present review summarizes the main findings resulting from the meta-analyses already completed.
RESULTS
Meta-analyses of randomized controlled trials conducted within POSITIVe suggest that age, sex, ethnicity, pathophysiological status and medication may be responsible for the heterogeneity in the biological responsiveness to (poly)phenol and phytosterol consumption and could lead to inconclusive results in some clinical trials aiming to demonstrate the health effects of specific dietary bioactive compounds. However, the contribution of these factors is not yet demonstrated consistently across all polyphenolic groups and cardiometabolic outcomes, partly due to the heterogeneity in trial designs, low granularity of data reporting, variety of food vectors and target populations, suggesting the need to implement more stringent reporting practices in the future studies. Studies investigating the effects of genetic background or gut microbiome on variability were limited and should be considered in future studies.
CONCLUSION
Understanding why some bioactive plant compounds work effectively in some individuals but not, or less, in others is crucial for a full consideration of these compounds in future strategies of personalized nutrition for a better prevention of cardiometabolic disease. However, there is also still a need for the development of a substantial evidence-base to develop health strategies, food products or lifestyle solutions that embrace this variability.
Topics: Biological Variation, Population; Cardiovascular System; Diet, Vegetarian; Europe; Humans; Metabolomics; Phytosterols; Plants, Edible; Polyphenols
PubMed: 31492975
DOI: 10.1007/s00394-019-02066-6 -
The New Phytologist Nov 2015Phytosterols are membrane components or precursors for brassinosteroid (BR) biosynthesis. As they cannot be transported long distances, their homeostasis is tightly...
Rice microRNA osa-miR1848 targets the obtusifoliol 14α-demethylase gene OsCYP51G3 and mediates the biosynthesis of phytosterols and brassinosteroids during development and in response to stress.
Phytosterols are membrane components or precursors for brassinosteroid (BR) biosynthesis. As they cannot be transported long distances, their homeostasis is tightly controlled through their biosynthesis and metabolism. However, it is unknown whether microRNAs are involved in their homeostatic regulation. Rice (Oryza sativa) plants transformed with microRNA osa-miR1848 and its target, the obtusifoliol 14α-demethylase gene, OsCYP51G3, were used to investigate the role of osa-miR1848 in the regulation of phytosterol biosynthesis. osa-miR1848 directs OsCYP51G3 mRNA cleavage to regulate phytosterol and BR biosynthesis in rice. The role of OsCYP51G3 as one of the osa-miR1848 targets is supported by the opposite expression patterns of osa-miR1848 and OsCYP51G3 in transgenic rice plants, and by the identification of OsCYP51G3 mRNA cleavage sites. Increased osa-miR1848 and decreased OsCYP51G3 expression reduced phytosterol and BR concentrations, and caused typical phenotypic changes related to phytosterol and BR deficiency, including dwarf plants, erect leaves, semi-sterile pollen grains, and shorter cells. Circadian expression of osa-miR1848 regulated the diurnal abundance of OsCYP51G3 transcript in developing organs, and the response of OsCYP51G3 to salt stress. We propose that osa-miR1848 regulates OsCYP51G3 expression posttranscriptionally, and mediates phytosterol and BR biosynthesis. osa-miR1848 and OsCYP51G3 might have potential applications in rice breeding to modulate leaf angle, and the size and quality of seeds.
Topics: Brassinosteroids; Circadian Rhythm; MicroRNAs; Oryza; Phenotype; Phytosterols; Plant Development; Sterol 14-Demethylase; Stress, Physiological
PubMed: 26083975
DOI: 10.1111/nph.13513 -
Proceedings of the National Academy of... Jan 2009The differences between the biosynthesis of sterols in higher plants and yeast/mammals are believed to originate at the cyclization step of oxidosqualene, which is...
The differences between the biosynthesis of sterols in higher plants and yeast/mammals are believed to originate at the cyclization step of oxidosqualene, which is cyclized to cycloartenol in higher plants and lanosterol in yeast/mammals. Recently, lanosterol synthase genes were identified from dicotyledonous plant species including Arabidopsis, suggesting that higher plants possess dual biosynthetic pathways to phytosterols via lanosterol, and through cycloartenol. To identify the biosynthetic pathway to phytosterol via lanosterol, and to reveal the contributions to phytosterol biosynthesis via each cycloartenol and lanosterol, we performed feeding experiments by using [6-(13)C(2)H(3)]mevalonate with Arabidopsis seedlings. Applying (13)C-{(1)H}{(2)H} nuclear magnetic resonance (NMR) techniques, the elucidation of deuterium on C-19 behavior of phytosterol provided evidence that small amounts of phytosterol were biosynthesized via lanosterol. The levels of phytosterol increased on overexpression of LAS1, and phytosterols derived from lanosterol were not observed in a LAS1-knockout plant. This is direct evidence to indicate that the biosynthetic pathway for phytosterol via lanosterol exists in plant cells. We designate the biosynthetic pathway to phytosterols via lanosterol "the lanosterol pathway." LAS1 expression is reported to be induced by the application of jasmonate and is thought to have evolved from an ancestral cycloartenol synthase to a triterpenoid synthase, such as beta-amyrin synthase and lupeol synthase. Considering this background, the lanosterol pathway may contribute to the biosynthesis of not only phytosterols, but also steroids as secondary metabolites.
Topics: Arabidopsis; Arabidopsis Proteins; Chromatography, High Pressure Liquid; Gas Chromatography-Mass Spectrometry; Intramolecular Transferases; Lanosterol; Mevalonic Acid; Phytosterols; Seedlings; Sitosterols; Triterpenes
PubMed: 19139393
DOI: 10.1073/pnas.0807675106 -
Journal of Chromatography. B,... Jun 2023Phytosterols are essential structural components of plant cell membranes and possess health-related benefits, including lowering blood cholesterol levels in humans....
Phytosterols are essential structural components of plant cell membranes and possess health-related benefits, including lowering blood cholesterol levels in humans. Numerous analytical methods are being used to profile plant and animal sterols. Chromatography hyphenated to tandem mass spectrometry, is a better option due to its specificity, selectivity, and sensitivity. An ultra-performance supercritical fluid chromatography hyphenated with atmospheric pressure chemical ionization (APCI) tandem mass spectrometric method was developed and evaluated for fingerprint analysis of seven phytosterols. Mass spectrometry fragmentation behavior was used for phytosterol identification, and multiple reaction monitoring scanning was utilized for phytosterol confirmation, where APCI outperformed superiority in terms of ion intensity, particularly in the production of [M + H-HO] ions rather than [M + H] ions. The chromatographic conditions were thoroughly evaluated, and the ionization parameters were optimized as well. In a 3 min. run, the seven phytosterols were separated concurrently. The calibration and repeatability tests were conducted to check the instrument's performance, and the results indicated that all of the phytosterols tested had correlation coefficients (r) greater than 0.9911 over the concentration range of 5-5000 ng/mL. The limit of quantification was below 20 ng/mL for all the tested analytes except for stigmasterol and campesterol. The partially validated method was applied for the evaluation of phytosterols in pure coconut oil and palm oil in order to demonstrate its applicability. Total sterols in coconut and palm oils were 126.77 ng/mL and 101.73 ng/mL, respectively. In comparison to earlier methods of phytosterol analysis, the novel method offers a far faster, more sensitive, and more selective analytical process.
Topics: Humans; Animals; Tandem Mass Spectrometry; Chromatography, Supercritical Fluid; Phytosterols; Sterols
PubMed: 37210885
DOI: 10.1016/j.jchromb.2023.123737 -
Molecules (Basel, Switzerland) Jan 2020Poor nutrition is an important factor in global bee population declines. A significant gap in knowledge persists regarding the role of various nutrients (especially...
Poor nutrition is an important factor in global bee population declines. A significant gap in knowledge persists regarding the role of various nutrients (especially micronutrients) in honey bees. Sterols are essential micronutrients in insect diets and play a physiologically vital role as precursors of important molting hormones and building blocks of cellular membranes. Sterol requirements and metabolism in honey bees are poorly understood. Among all pollen sterols, 24-methylenecholesterol is considered the key phytosterol required by honey bees. Nurse bees assimilate this sterol from dietary sources and store it in their tissues as endogenous sterol, to be transferred to the growing larvae through brood food. This study examined the duration of replacement of such endogenous sterols in honey bees. The dietary C-labeled isotopomer of 24-methylenecholesterol added to artificial bee diet showed differential, progressive in vivo assimilation across various honey bee tissues. Significantly higher survival, diet consumption, head protein content and abdominal lipid content were observed in the dietary sterol-supplemented group than in the control group. These findings provide novel insights into phytosterol utilization and temporal pattern of endogenous 24-methylenecholesterol replacement in honey bees.
Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Bees; Feeding Behavior; Insect Proteins; Lipid Metabolism; Phytosterols; Survival Rate
PubMed: 32012964
DOI: 10.3390/molecules25030571 -
Molecular Nutrition & Food Research Aug 2017Phytosterols are bioactive compounds in plants with similar cholesterol-lowering properties as vegetarian diets. However, information on phytosterol intake and plasma...
SCOPE
Phytosterols are bioactive compounds in plants with similar cholesterol-lowering properties as vegetarian diets. However, information on phytosterol intake and plasma plant sterols among vegetarians is sparse.
METHODS AND RESULTS
We examined dietary intake and plasma concentration of plant sterols and cholesterol across five dietary patterns in the Adventist Health Study-2 Calibration Sub-study (n = 861, 66% females, average age 61 years). To measure intake and plasma concentrations of these compounds, we used 24-h dietary recalls and gas-liquid chromatography-flame ionization detection, respectively. Mean (SD) total phytosterol and cholesterol intake were 363 (176) mg/day and 131 (111) mg/day; plasma β-sitosterol, campesterol, and cholesterol were 3.3 (1.7) μg/mL, 4.2 (2.3) μg/mL, and 1.9 (0.4) mg/mL, respectively. Total phytosterol intake was lowest among non-vegetarians (263 mg/day) and highest among vegans (428 mg/day) (p < 0.0001). Cholesterol intake was lowest among vegans (15.2 mg/day) and highest among non-vegetarians (124.6 mg/day) (p < 0.0001). Plasma plant sterols and cholesterol did not differ by diet. Cholesterol-adjusted plasma β-sitosterol and campesterol were significantly higher in Blacks than Whites, though no ethnic differences were observed in dietary intake of these plant sterols.
CONCLUSION
Dietary intake but not plasma concentration of plant sterols and cholesterol varies across distinct plant-based diets.
Topics: Aged; Cholesterol; Cross-Sectional Studies; Diet; Diet, Vegetarian; Female; Humans; Male; Middle Aged; North America; Nutrition Surveys; Phytosterols; Sitosterols
PubMed: 28130879
DOI: 10.1002/mnfr.201600828