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Lipids Sep 2010Plant sterols and stanols (phytosterols) and their esters are nutraceuticals that lower LDL cholesterol, but the mechanisms of action are not fully understood. We...
Plant sterols and stanols (phytosterols) and their esters are nutraceuticals that lower LDL cholesterol, but the mechanisms of action are not fully understood. We hypothesized that intact esters and simulated hydrolysis products of esters (phytosterols and fatty acids in equal ratios) would differentially affect the solubility of cholesterol in model bile mixed micelles in vitro. Sodium salts of glycine- and taurine-conjugated bile acids were sonicated with phosphatidylcholine and either sterol esters or combinations of sterols and fatty acids to determine the amount of cholesterol solubilized into micelles. Intact sterol esters did not solubilize into micelles, nor did they alter cholesterol solubility. However, free sterols and fatty acids altered cholesterol solubility independently (no interaction effect). Equal contents of cholesterol and either campesterol, stigmasterol, sitosterol, or stigmastanol (sitostanol) decreased cholesterol solubility in micelles by approximately 50% compared to no phytosterol present, with stigmasterol performing slightly better than sitosterol. Phytosterols competed with cholesterol in a dose-dependent manner, demonstrating a 1:1 M substitution of phytosterol for cholesterol in micelle preparations. Unsaturated fatty acids increased the micelle solubility of sterols as compared with saturated or no fatty acids. No differences were detected in the size of the model micelles. Together, these data indicate that stigmasterol combined with saturated fatty acids may be more effective at lowering cholesterol micelle solubility in vivo.
Topics: Bile Acids and Salts; Cholesterol; Micelles; Phytosterols; Sitosterols; Solubility; Stigmasterol
PubMed: 20706798
DOI: 10.1007/s11745-010-3456-6 -
Scientific Reports May 2024Phytosterols are natural components of plant-based foods used as supplements because of their known cholesterol-lowering effect. However, their effects on lipoprotein... (Randomized Controlled Trial)
Randomized Controlled Trial
Phytosterols are natural components of plant-based foods used as supplements because of their known cholesterol-lowering effect. However, their effects on lipoprotein subfractions and the quality of the LDL particle have not been studied in greater detail. We aimed to evaluate the effects of phytosterols supplements on lipids, lipoproteins subfractions, and on the quality of LDL. A prospective, pilot-type, open label, cross-over study, randomized 23 males in primary prevention of hypercholesterolemia to receive diet or diet plus phytosterol (2.6 g in 2 doses, with meals) for 12 weeks, when treatments were switched for another 12 weeks. Lipoprotein subfractions were analyzed by electrophoresis in polyacrylamide gel (Lipoprint System®). The Sampson equation estimated the small and dense (sd) and large and buoyant (lb) LDL subfractions from the lipid profile. Quality of LDL particle was analyzed by Z-scan and UV-vis spectroscopy. Primary outcome was the comparison of diet vs. diet plus phytosterols. Secondary outcomes assessed differences between baseline, diet and diet plus phytosterol. Non-parametric statistics were performed with p < 0.05. There was a trend to reduction on HDL-7 (p = 0.05) in diet plus phytosterol arm, with no effects on the quality of LDL particles. Heatmap showed strong correlations (ρ > 0.7) between particle size by different methods with both interventions. Diet plus phytosterol reduced TC, increased HDL-c, and reduced IDL-B, whereas diet increased HDL7, and reduced IDL-B vs. baseline (p < 0.05, for all). Phytosterol supplementation demonstrated small beneficial effects on HDL-7 subfraction, compared with diet alone, without effects on the quality of LDL particles.This trial is registered in Clinical Trials (NCT06127732) and can be accessed at https://clinicaltrials.gov .
Topics: Phytosterols; Humans; Male; Dietary Supplements; Middle Aged; Hypercholesterolemia; Cross-Over Studies; Lipoproteins, LDL; Prospective Studies; Adult; Cholesterol, LDL; Pilot Projects; Lipoproteins
PubMed: 38750162
DOI: 10.1038/s41598-024-61897-4 -
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 -
Journal of Nutritional Science and... Aug 2003Phytosterol contained in vegetable oils is known to exert a hypocholesterolemic function. In the present study, the antioxidant effects of phytosterol and its...
Phytosterol contained in vegetable oils is known to exert a hypocholesterolemic function. In the present study, the antioxidant effects of phytosterol and its components, beta-sitosterol, stigmasterol, and campesterol, against lipid peroxidation were examined by making a comparison with 2,2,5,7,8-pentamethyl-6-chromanol (PMC). It was found that these compounds exerted antioxidant effects on the oxidation of methyl linoleate in solution and its effect decreased in the order of: PMC >> phytosterol approximately campesterol approximately beta-sitosterol > stigmasterol. Phytosterol also suppressed the oxidation and consumption of alpha-tocopherol in beta-linoleoyl-gamma-palmitoyl phosphatidylcholine (PLPC) liposomal membranes, the effects being more significant than dimyristoyl PC of the same concentration. Stigmasterol accelerated the oxidation of both methyl linoleate in solution and PLPC liposomal membranes in aqueous dispersions, which was ascribed to the oxidation of allylic hydrogens at the 21- and 24-positions. Taken together, the present study shows that phytosterol chemically acts as an antioxidant, a modest radical scavenger, and physically as a stabilizer in the membranes.
Topics: Anticholesteremic Agents; Antioxidants; Cholesterol; Chromans; Free Radical Scavengers; Lipid Peroxidation; Liposomes; Membranes, Artificial; Oxidation-Reduction; Phytosterols; Sitosterols; Stigmasterol
PubMed: 14598915
DOI: 10.3177/jnsv.49.277 -
Phytochemistry Aug 2006The Zygomycetes fungus Mortierella alpina was cultured to growth arrest to assess the phytosterol biosynthesis pathway in a less-advanced fungus. The mycelium was found...
The Zygomycetes fungus Mortierella alpina was cultured to growth arrest to assess the phytosterol biosynthesis pathway in a less-advanced fungus. The mycelium was found to produce 13 sterols, but no ergosterol. The sterol fractions were purified to homogeneity by HPLC and their identifies determined by a combination of GC-MS and 1H NMR spectroscopy. The principal sterol of the mycelium was cholesta-5, 24-dienol (desmosterol) (83%), with lesser amounts of 24beta-methyl-cholesta-5,25(27)-dienol (codisterol) (2%), 24-methyldesmosterol (6%), 24(28)-methylene cholesterol (3%) and lanosterol (3%) and several other minor compounds (3%). The total sterol accounted for approximately 0.07% of the mycelial dry wt. Mycelium fed methionine-methyl-2H3 for 6 days, generated 3 2H-24-methyl(ene) sterols, [C28-2H2]24(28)-methylenecholesterol, [C28-2H3]24-methylcholesta-5,24-dienol and [C28-2H3]24beta-methyl-cholesta-5,25(27)-dienol. The formation of the 24-methyl sterols seems to be catalyzed by the direct methylation of a common Delta24-acceptor sterol thereby bypassing the intermediacy of an isomerization step for rearrangement of the Delta24(28)-bond to Delta25(25)-position as operates in Ascomycetes fungi and all plants.
Topics: Gas Chromatography-Mass Spectrometry; Magnetic Resonance Spectroscopy; Mortierella; Phytosterols
PubMed: 16647729
DOI: 10.1016/j.phytochem.2006.02.023 -
Food Research International (Ottawa,... May 2020HPLC analyses of phytosterols are associated with the issues of sensitivity due to their high lipophilicity and their lack of chromophore. These problems could be solved...
HPLC analyses of phytosterols are associated with the issues of sensitivity due to their high lipophilicity and their lack of chromophore. These problems could be solved through chemical modifications of plant sterols/stanols structures. Therefore, the present study aims to develop a new method for phytosterols derivatization. This method was performed using dansyl chloride (4 mg ml) as derivatizing agent and different reaction parameters have been optimized. The highest yields of phytosterol derivatization were obtained with 4-dimethylaminopyridine (DMAP) as catalyst at a concentration of 8 mg ml and dichloromethane as reaction solvent. In addition, 40 ˚C was the best reaction temperature for 30 min as the best reaction time. This derivatization method presented a high reproducibility (%RSD = 1.2-2.7%) and a good linearity (R = 0.9982-0.9999). The UV absorption intensities after derivatization showed a 23-fold increment for plant sterols and a 400-fold increment for plant stanols. Moreover, this derivatization method allowed the use of high and more selective wavelengths of detection and improved the chromatographic separation of phytosterols. Furthermore, the developed method allowed the ESI-MS ionization and analysis of phytosterols. This method can therefore contribute to the improvement of the HPLC analyses of plant sterols/stanols.
Topics: Chromatography, High Pressure Liquid; Molecular Structure; Phytosterols; Spectrometry, Mass, Electrospray Ionization; Temperature
PubMed: 32247468
DOI: 10.1016/j.foodres.2020.108998 -
Food & Function Sep 2016Algae oil, enriched with omega-3 long-chain polyunsaturated fatty acids (ω-3 LC-PUFA), is known for its health benefits. However, protection against lipid oxidation as...
Algae oil, enriched with omega-3 long-chain polyunsaturated fatty acids (ω-3 LC-PUFA), is known for its health benefits. However, protection against lipid oxidation as well as masking of unpleasant fishy malodors in algae oil enriched foods is a big challenge to achieve. In this study, we firstly achieved a one-pot ultrasound emulsification strategy (alternative heating-homogenization) to prepare phytosterol structured thermosensitive algae oil-in-water nanoemulsion stabilized by quillaja saponin. After spray drying, the resulting algae oil powders from the structured nanoemulsion templates exhibit an excellent reconstructed behavior, even after 30 d of storage. Furthermore, an enhanced oxidative stability was obtained by reducing both the primary and secondary oxidation products through formulation with β-sitosterol and γ-oryzanol, which are natural antioxidants. Following the results of headspace volatiles using dynamic headspace-gas chromatography-mass spectrometry (DHS-GC-MS), it was clear that the structured algae oil-loaded nanoemulsion and powder had lower levels of fishy off-flavour (e.g., (Z)-heptenal, decanal, ethanone, and hexadecenoic acid), whereas the control emulsion and oil powder without structure performed worse. This study demonstrated that the structure from phytosterols is an effective strategy to minimize the fishy off-flavour and maximize oxidative stability of both algae oil nanoemulsions and spray-dried powders, and opens up the possibility of formulation design in polyunsaturated oil encapsulates as novel delivery systems to apply in functional foods and beverages.
Topics: Antioxidants; Drug Stability; Emulsions; Fatty Acids, Omega-3; Food, Fortified; Odorants; Oils; Phenylpropionates; Phytosterols; Powders; Quillaja Saponins; Sitosterols; Taste
PubMed: 27501908
DOI: 10.1039/c6fo00449k -
The British Journal of Nutrition Mar 2017A study in rodent models showed that phytosterols protected against colon carcinogenesis, probably by inhibiting dysregulated cell cycle progression and inducing...
A study in rodent models showed that phytosterols protected against colon carcinogenesis, probably by inhibiting dysregulated cell cycle progression and inducing cellular apoptosis. However, epidemiological studies on the relationship between phytosterols and colorectal cancer risk are quite limited. The aim of this study was to investigate dietary phytosterol intake in relation to colorectal cancer risk in the Chinese population. A case-control study was conducted from July 2010 to June 2016, recruiting 1802 eligible colorectal cancer cases plus 1813 age (5-year interval) and sex frequency-matched controls. Dietary information was collected by using a validated FFQ. The OR and 95 % CI of colorectal cancer risk were assessed by multivariable logistic regression models. A higher total intake of phytosterols was found to be associated with a 50 % reduction in colorectal cancer risk. After adjusting for various confounders, the OR of the highest quartile intake compared with the lowest quartile intake was 0·50 (95 % CI 0·41, 0·61, P trend<0·01) for total phytosterols. An inverse association was also found between the consumption of β-sitosterol, campesterol, campestanol and colorectal cancer risk. However, stigmasterol intake was related to an increased risk of colorectal cancer. No statistically significant association was found between β-sitostanol and colorectal cancer risk. Stratified analysis by sex showed that the positive association of stigmasterol intake with colorectal cancer risk was found only in women. These data indicated that the consumption of total phytosterols, β-sitosterol, campesterol and campestanol is inversely associated with colorectal cancer risk in a Chinese population.
Topics: Adult; Aged; Aged, 80 and over; Case-Control Studies; China; Colorectal Neoplasms; Diet; Energy Intake; Feeding Behavior; Female; Humans; Logistic Models; Male; Middle Aged; Odds Ratio; Phytosterols; Plant Extracts; Risk; Sex Factors; Sitosterols
PubMed: 28382872
DOI: 10.1017/S0007114517000617 -
Public Health Nutrition Jan 2009To study patterns of phytosterol intakes in the Irish population from enriched sources.
OBJECTIVE
To study patterns of phytosterol intakes in the Irish population from enriched sources.
DESIGN
An interview-assisted questionnaire, which recorded information on sociodemographics, product types, intake amounts and patterns of intake. Independent samples t tests, one-way ANOVA and cross-tabulations were used to establish significant relationships between groups of variables. The top tertile of phytosterol intakes was also calculated.
SETTING
Point-of-purchase of phytosterol-enriched products in Irish supermarkets.
SUBJECTS
Four hundred and sixty-eight consumers (186 men and 282 women) of phytosterol-enriched foods.
RESULTS
The mean phytosterol intake from enriched sources for the sample population was 2.45 g/d. Men had greater intakes than women (2.71 g/d v. 2.29 g/d, respectively). A total of 62 % of consumers were unaware of the importance of consuming fruit and vegetables while taking these products. The majority of respondents reported that they had high cholesterol (61 %) and 22 % of consumers also took cholesterol-lowering medication (statins). In total, 23 % had phytosterol intakes >3.0 g/d and the majority of consumers (58 %) had been consuming these products for >1 year. The mean intake for respondents with phytosterol intakes >3.0 g/d was 4.1 g/d and 74 % of this subgroup had been consuming these products for >1 year.
CONCLUSION
In general, phytosterol intakes are within efficacious levels in the Irish population. However, there appears to be a subgroup that has been consuming these products at intakes greater than current recommendations for >1 year.
Topics: Adult; Analysis of Variance; Diet; Female; Food, Fortified; Humans; Hypercholesterolemia; Ireland; Male; Phytosterols; Surveys and Questionnaires
PubMed: 18312704
DOI: 10.1017/S1368980008001766 -
Molecules (Basel, Switzerland) Dec 2020This study investigated how the physicochemical characteristics of phytosterol esters are influenced by the chain length and degree of unsaturation of the fatty acid...
This study investigated how the physicochemical characteristics of phytosterol esters are influenced by the chain length and degree of unsaturation of the fatty acid ester moiety. Saturated and unsaturated phytosterol esters (PEs) were synthesized by the esterification of different types of fatty acids (stearic, palmitic, lauric, oleic, and linoleic acid) to β-sitosterol. The non-isothermal crystallization and melting behavior of the pure PEs were analyzed. It was proven by X-ray diffraction that saturated β-sitosteryl esters and β-sitosteryl oleate formed a bilayer crystal structure. The lamellar spacings of the bilayer structure decreased with decreasing fatty acid chain length and with an increasing degree in unsaturation. The degree of unsaturation of the fatty acid chain of the β-sitosteryl esters also influenced the type of subcell packing of the fatty acid moieties in the bilayer structure, whether or not a metastable or stable liquid crystalline phase was formed during cooling. Furthermore, it was found that the melting temperature and enthalpy of the β-sitosteryl esters increased with an increasing fatty acid chain length while they decreased with an increasing degree of unsaturation. The microscopic analyses demonstrated that β-sitosteryl oleate formed much smaller spherulites than their saturated β-sitosteryl analogues.
Topics: Crystallization; Esters; Fatty Acids; Phytosterols; Sitosterols; Temperature; X-Ray Diffraction
PubMed: 33291641
DOI: 10.3390/molecules25235727