Phytosterols In Oil Research Articles

Physicochemical Characterization of Yellow Cake Prepared with Structured Lipid Oleogels.

Oleogels were produced using a phytosterol blend of β-sitosterol/γ-oryzanol or a blend of sucrose stearate/ascorbyl palmitate (SSAP) as oleogelators. Four lipid phases were compared in oleogel formation for each oleogelator blend: menhaden oil, structured lipid (SL) of menhaden oil and 30 mol% caprylic acid (SL-C), SL of menhaden oil and 20 mol% stearic acid (SL-S), and SL of menhaden oil and 14 mol% each of caprylic and stearic acid (SL-CS). All SLs were produced enzymatically using a recombinant lipase from Candida antarctica as the biocatalyst. Menhaden oil, SL, phytosterol, or SSAP oleogels were evaluated as alternatives to shortening in the preparation of yellow cake in terms of batter and cake physicochemical properties. The shortening, phytosterol, and SSAP oleogel batters exhibited statistically similar specific gravities (0.85). The shortening, and menhaden oil phytosterol and SSAP oleogel batters, exhibited similar Power-Law values (n: 0.78, k: 31 Pa sn ), while all SL (and respective oleogels) batters typically had lower flow index values (n: 0.68 to 0.72), and higher consistency index values (k: 45 to 79 Pa sn ). All SL (and respective oleogels) cakes exhibited lower hardness (5 to 8 N) and chewiness (4 to 6 N) than the shortening cake (12 N, 9 N). Menhaden oil and SL-S phytosterol oleogel cakes, and SL-CS SSAP oleogel cake, showed similar textural properties to the shortening cake. Both phytosterol and SSAP oleogels were acceptable as zero trans-fat substitutes for shortening in yellow cake. PRACTICAL APPLICATION: The oleogels in this study may be a suitable replacement for shortening in yellow cake. These oleogels, which contain health beneficial omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have the potential to lower consumer consumption of total saturated fat when used in foods.

Physico-chemical Characteristics of Washingtonia robusta Fruit Oil

The fruit seed kernel oil from Washingtonia (W. robusta) locally in Aswan governorate, Egypt were evaluated for their physicochemical properties, and composition of fatty acids, tocopherols and phytosterols. The contents of carbohydrates, fiber, protein and ash for W. robusta palm fruits were 47.00, 6.50, 5 and 4.2%, respectively. The oil content in the seed kernels was 32.80%. The extracted oil had as refractive index (at 20oC) 1.46, specific gravity (at 20oC) 0.92, colour (yellow, 3.5; red 0.09), average iodine value (g of I/100g oil) 87.68; acid value (% oleic acid) 0.22%; saponification value (191.66 mg of KOH/g oil; unsaponifiable matters 0.70, the oxidation stability was 30. The major fatty acids detected in oil were noted to be oleic acid (64.80%) followed by palmitic acid (14.40%), linolenic acid (5.20%), arachidic acid (5.10%), linoleic acid (4.50), stearic acid (4.30) and myrstic acid (1.70%). The observed data showed that the total saturated fatty acids 25.50%, whereas the amounts of total unsaturated fatty acids 74.50%.The content of total tocopherols in oil was 97.4 mg/100g), with α-tocophero l16.0, γ-tocophero l31.4, and δ-tocopherol (50 mg/100g). β-sitosterol (11.331 mg/100 g) the main phytosterols in oil. The results of this study revealed that the Washingtonia robusta fruit could be explained as a potential source of high-oleic oil for the local oil industry as well as the seeds is a nutritive value.

Rapid determination of phytosterols by NIRS and chemometric methods.

Phytosterols have been extensively studied because it plays essential roles in the physiology of plants and can be used as nutritional supplement to promote human health. We use a rapid method by coupling near-infrared spectroscopy (NIRS) and chemometric techniques to quickly and efficiently determine three essential phytosterols (β-sitosterol, campesterol and stigmasterol) in vegetable oils. Continuous wavelet transform (CWT) method was adopted to remove the baseline shift in the spectra. The quantitative analysis models were constructed by partial least squares (PLS) regression and randomization test (RT) method was used to further improve the models. The optimized models were used to calculate the phytosterol contents in prediction set in order to evaluate their predictability. We have found that the phytosterol contents obtained by the optimized models and Gas Chromatography/Mass Spectrometry (GC/MS) analysis are almost consistent. The root mean square error of prediction (RMSEP) and ratio of prediction to deviation (RPD) for the three phytosterols are 525.7590, 212.2245, 65.1611 and 4.0060, 4.7195 and 3.5441, respectively. The results have proved the feasibility of the proposed method for rapid and non-destructive analysis of phytosterols in edible oils.

Dispersed free phytosterols as structuring agents in lipid systems with reduced saturated fat

The negative effects of trans fatty acids and saturated fatty acids in food have been widely discussed and this has led to progressive changes in the legislation of many countries. The use of structuring agents or crystallization modifiers, as specific triacylglycerol and minor lipids have been indicated as the only viable alternative for obtaining low saturated fats with properties which are compatible with food application. In this context, phytosterols, natural products with hypocholesterolemic action, and hard fat-crystallization modulators, present a new option for structuring lipid matrices. This work characterized the effects of fully hydrogenated soybean oil and free phytosterols on the physical properties and crystallization behavior of palm oil and canola oil blends for the development of zero trans-fat bases with low levels of saturated fatty acids. The systems were evaluated for chemical composition, atherogenic index, solid fat profiles, microstructure, consistency, thermal behavior and polymorphism.

Dynamics of phytosterols content and concentration in sunflower grains

Phytosterols are allies in the control of plasma cholesterol and in preventing cardiovascular diseases. As vegetable oils are the main source of phytosterols, characterising environmental factors that determine phytosterols accumulation in the oil is an important objective. The present research focuses on evaluating how intercepted solar radiation (ISR, the main environmental factor affecting oil accumulation) can determine phytosterol accumulation in sunflower oil. The aim of this work was to study the dynamics of phytosterols accumulation under different ISR levels and its relationships with the dynamics of oil accumulation. Two field experiments were conducted with hybrids with different fatty acid composition. Treatments applied during grain filling were: two levels of defoliation (75% and 80%) and a control. A 50% grain thinning treatment was also applied. Oil phytosterols concentration increased with defoliation during grain-filling period, whereas phytosterols content per grain decreased. β-sitosterol and campesterol were the most affected sterols. Reduction in ISR did not affect the rates of phytosterols accumulation. The durations of the accumulation period of these components varied in accordance with the duration of oil accumulation period. These results reinforce the importance of environmental factor in determining oil quality in sunflower grains.

An Analytical Simplification for Faster Determination of Fatty Acid Composition and Phytosterols in Seed Oils

The fatty acid composition and the amounts of individual and total sterols in vegetable oils are the main analyses applied in the food industry to establish the oil nature. While the fatty acid composition is a relatively simple, fast analysis, the determination of phytosterols requires a laborious and time-consuming sample preparation. Both methods require a relatively large amount of oil, which may be an important drawback when only small samples are available. In this study, an analytical procedure that combines the sample preparation of both determinations is proposed to analyze small amounts of seed oils. From a single sample preparation, the total analysis time was considerably shortened. By applying a total methylation, the triacylglycerols and free fatty acids were transformed into fatty acid methyl ester (FAME) derivatives. Likewise, free sterols were completely released from their conjugated forms. Then, the derivatized oil was fractionated by solid-phase extraction into two fractions containing the FAME and free sterols, respectively. Both fractions were analyzed by gas-liquid chromatography. The analytical changes introduced provided reliable results for the main fatty acids and the major sterols in terms of accuracy and repeatability. Compared to the standard procedures, the time for sample preparation was reduced by half. In addition, it was much less laborious and required less volume of organic solvents, which reduced considerably the total cost of analysis and solvent waste. Consequently, the method proposed can be adopted as routine analysis in laboratories of oil quality control in the food industry.

Development of an ultrasound assisted method for determination of phytosterols in vegetable oil

The aims of this study were the optimization and validation of a new ultrasound assisted phytosterol method through analysis of response surface generated from Box-Behnken design. Variables quantity of sample (g), volume of KOH/MeOH (mL) and ultrasound time (s) were investigated in three levels. The evaluation process of the methodology was executed through determination of analytical parameters, such as selectivity, linearity, accuracy, dynamic linear range, “intra-day” accuracy and limits of detection and quantification. Optimized conditions for stigmasterol determination were 0.25g; 2.5mL; 300s; and β-sitosterol were 0.25g; 5.4mL; 300s. The evaluated conditions and all investigated analytical parameters showed that the method is effective for determination of analytes β-sitosterol and stigmasterol. This new analytical method has the same efficiency of the traditional method, while significantly reducing the total time of extraction for 300s regarding saponification step when compared to 3600s from the traditional method.

Metal ions accelerated phytosterol thermal degradation on Ring A & Ring B of steroid nucleus in oils

This study aimed to investigate the effect of metal ions on the degradation of phytosterols in oils. The oil was heated at 180°C for 1h with/without addition of Fe3+, Fe2+, Cu2+, Mn2+, Zn2+, Na+, Al3+ and Mg2+. Variations of β-sitosterol, stigmasterol, campesterol, brassicasterol and their degradation products were confirmed by the GC–MS analysis. In general, the increase of the metal ion concentration resulted in more phytosterol degradation, and the ability of metal ions following decreasing order: Fe3+>Fe2+>Mn2+≥Cu2+≥Zn2+>Na+≥Mg2+>Al3+. Metal ions significantly induced phytosterol autoxidation on C5, C6 and C7 on Ring B of steroid nucleus at even a low concentration, and induced dehydration on the C3 hydroxyl to form dienes and trienes at high concentration. The metal ions in oils are accounted for increasing phytosterol degradation, which decreases food nutritional quality and gives rise to the formation of undesirable compounds.

Half-life of plasma phytosterols in very low birth weight preterm infants on routine parenteral nutrition with vegetable oil-based lipid emulsions

Phytosterols in vegetable oil (VO)-based lipid emulsions (LE) likely contribute to parenteral nutrition-associated cholestasis (PNAC) in preterm infants. No characterization of plasma phytosterol half-lives has been done in very low birth weight (VLBW) preterm infants receiving parenteral nutrition (PN) with LE. In a prospective cohort study, 45 VLBW preterm infants who received PN underwent serial blood sample measurements of sitosterol (SITO), campesterol (CAMP), and stigmasterol (STIGM). Plasma phytosterol half-lives were calculated from the phytosterol concentrations-decay curves by using a single-compartment model. After the stop of the intravenous LE, study infants had significantly lower plasma total CAMP, STIGM and SITO concentrations. The decay of plasma phytosterol concentrations was monoexponential. Half-life of plasma total CAMP, STIGM and SITO was 13.5±6.9, 10.3±4.5 and 10.3±4.0 days, respectively. Plasma phytosterol half-lives did not correlate with gestational age, birth weight, cumulative phytosterol intakes and plasma conjugated bilirubin. VLBW preterm infants on PN with LE had rather long plasma phytosterol half-lives similar to hypercholesterolemic adults and phytosterolemic homozygotes patients. We speculate that the accumulation of phytosterols could contribute to their vulnerability to PNAC. The Ethics Committee of Marche-Italy (DG/469); www.clinicaltrials.gov (identification number NCT02758834).

Rapid and sensitive determination of phytosterols in functional foods and medicinal herbs by using UHPLC-MS/MS with microwave-assisted derivatization combined with dual ultrasound-assisted dispersive liquid-liquid microextraction.

In this work, a hyphenated technique of dual ultrasound-assisted dispersive liquid-liquid microextraction combined with microwave-assisted derivatization followed by ultra high performance liquid chromatography tandem mass spectrometry has been developed for the determination of phytosterols in functional foods and medicinal herbs. Multiple reaction monitoring mode was used for the tandem mass spectrometry detection. A mass spectrometry sensitive reagent, 4'-carboxy-substituted rosamine, has been used as the derivatization reagent for five phytosterols, and internal standard diosgenin was used for the first time. Parameters for the dual microextraction, microwave-assisted derivatization, and ultra high performance liquid chromatography tandem mass spectrometry were all optimized in detail. Satisfactory linearity, recovery, repeatability, accuracy and precision, absence of matrix effect, extremely low limits of detection (0.005-0.015 ng/mL) and limits of quantification (0.030-0.10 ng/mL) were achieved. The proposed method was compared with previously reported methods. It showed better sensitivity, selectivity, and accuracy. The matrix effect was also significantly reduced. The proposed method was successfully applied to the determination of five phytosterols in vegetable oil (sunflower oil, olive oil, corn oil, peanut oil), milk and orange juice (soymilk, peanut milk, orange juice), and medicinal herbs (Ginseng, Ganoderma lucidum, Cordyceps, Polygonum multiflorum) for the quality control of functional foods and medicinal herbs.

Single step biotransformation of corn oil phytosterols to boldenone by a newly isolated Pseudomonas aeruginosa

A new potent Pseudomonas aeruginosa isolate capable for biotransformation of corn oil phytosterol (PS) to 4-androstene-3, 17-dione (AD), testosterone (T) and boldenone (BOL) was identified by phenotypic analysis and 16S rRNA gene sequencing. Sequential statistical strategy was used to optimize the biotransformation process mainly concerning BOL using Factorial design and response surface methodology (RSM). The production of BOL in single step microbial biotransformation from corn oil phytosterols by P. aeruginosa was not previously reported. Results showed that the pH concentration of the medium, (NH4)2SO4 and KH2PO4 were the most significant factors affecting BOL production. By analyzing the statistical model of three-dimensional surface plot, BOL production increased from 36.8% to 42.4% after the first step of optimization, and the overall biotransformation increased to 51.9%. After applying the second step of the sequential statistical strategy BOL production increased to 53.6%, and the overall biotransformation increased to 91.9% using the following optimized medium composition (g/l distilled water) (NH4)2SO4, 2; KH2PO4, 4; Na2HPO4. 1; MgSO4·7H2O, 0.3; NaCl, 0.1; CaCl2·2H2O, 0.1; FeSO4·7H2O, 0.001; ammonium acetate 0.001; Tween 80, 0.05%; corn oil 0.5%; 8-hydroxyquinoline 0.016; pH 8; 200rpm agitation speed and incubation time 36h at 30°C. Validation experiments proved the adequacy and accuracy of model, and the results showed the predicted value agreed well with the experimental values.

Rapid fingerprinting of sterols and related compounds in vegetable and animal oils and phytosterol enriched- margarines by transmission mode direct analysis in real time mass spectrometry

Plant-derived sterols, often referred to as phytosterols, are important constituents of plant membranes where they assist in maintaining phospholipid bilayer stability. Consumption of phytosterols has been suggested to positively affect human health by reducing cholesterol levels in blood via inhibition of its absorption in the small intestine, thus protecting against heart attack and stroke. Sterols are challenging analytes for mass spectrometry, since their low polarity makes them difficult to ionize by both electrospray ionization (ESI) and matrix-assisted laser desorption ionization (MALDI), typically requiring derivatization steps to overcome their low ionization efficiencies. We present a fast and reliable method to characterize the composition of phytosterols in vegetable oils and enriched margarines. The method requires no derivatization steps or sample extraction procedures thanks to the use of transmission mode direct analysis in real time mass spectrometry (TM-DART-MS).

Canolol, tocopherols, plastochromanol‐8, and phytosterols content in residual oil extracted from rapeseed expeller cake obtained from roasted seed

Due to the high canolol content rapeseed oil is increasingly often pressed from seeds subjected to the roasting process. However, there is a lack of data on the contents of canolol in residual oil produced from cake, a by‐product of cold pressing. The aim of this study was to investigate the contents of bioactive substances contained in expeller cake generated in cold pressing of rapeseed oil from seeds roasted at a temperature of 140, 160, and 180°C for 5, 10, and 15 min. Contents of tocopherols, plastochromanol‐8, and canolol were analyzed using the NP‐HPLC‐FL method, while contents of phytosterols – by GC‐FID. Based on the recorded data it may be concluded that 180°C is the best temperature for seed roasting, since at that temperature the greatest amount of canolol is formed and most of it passes to oil in the course of cold pressing. Contents of tocopherols in the tested oils ranged from 88.48 to 90.51 mg/100 g. A lower tocopherol content was recorded in residual oil of the press cakes in comparison to cold‐pressed oil, particularly in the case of samples roasted at a temperature of 160 and 180°C. Content of PC‐8 was higher in residual oil by over 4 mg/100 g in comparison to cold‐pressed oil. Also the total content of phytosterols in oils produced by solvent extraction from cake was higher than in cold‐pressed oil. Contents of phytosterols ranged from 4141.9 to 4826.1 μg/g oil.Practical application: Rapeseeds increasingly often are subjected to roasting prior to the cold pressing process. During roasting canolol is formed, which as a product of decarboxylation of sinapic acid, more efficiently penetrates to oil in comparison to sinapic acid. However, there is no data concerning the amounts of canolol remained in press cake. This study investigated the effect of temperature of rapeseed roasting on the content of bioactive compounds (tocopherols, PC‐8, phytosterols, and canolol) in residual oil from press cake. Results recorded in this study facilitate selection of roasting parameters so that the lowest possible amounts of bioactive compounds are retained in cake and they rather pass to cold‐pressed oil, enriching it and indirectly contributing to an enhancement of its oxidative stability. On the other hand, these results show that the expeller cake (from roasted seeds) as a by‐product can be further treated as a good source of bioactive compounds including canolol. They can also be used as a practical supplement to animal feed.This study investigates the effect of rapeseed roasting at a temperature of 140, 160, and 180°C for 5, 10, and 15 min on the content of residual oil and its composition in terms of such bioactive substances as tocopherols, PC‐8, phytosterols, and canolol. It is seen that residual oil extracted from rapeseed cake subjected to roasting has lower contents of tocopherols (particularly in the case of samples roasted at 160 and 180°C). PC‐8 is more effectively extracted with an organic solvent, since its content in residual oil was by 4 mg/100 g higher than in cold‐pressed oil. Also the content of phytosterols is higher in residual oil than in cold‐pressed oil. Contents of phytosterols ranges from 4141.9 to 4826.1 mg/g oil. Based on the recorded data it may be concluded that 180°C is the best temperature for seed roasting, since at that temperature the greatest amount of canolol is formed and most of it passes to oil in the course of cold pressing.

Natural variability in phytosterols in almond (Prunus amygdalus) trees growing under a southern Mediterranean climate

SUMMARYAlmond (Prunus amygdalus) kernels are an important source of phytosterols that are considered essential elements for human health. Little information is available on the variability and composition of phytosterols in cultivated almond, and there is no information on wild almond such as those that have originated in Morocco. High levels of variability in phytosterol concentrations were found among 23 accessions of Moroccan almond, ranging from 1,174–2,072 mg kg−1 kernel dry weight, and from 2,184–3,582 mg kg−1 for oil phytosterol, within the ranges published for other almond genotypes. Major components of the phytosterol fraction were β-sitosterol [55.9–84.6% (w/w)] and ▵5-avenasterol [8.5–28.2% (w/w)]. Significant differences in phytosterol concentrations and compositions were observed between almond seedlings as well as between almonds of different geographical origin, possibly due to a positive effect of higher temperatures. Some genotypes, such as Al4 with high concentrations of phytosterols (3,582 mg kg−1 of oil phytosterol) could be used as parents in almond breeding programmes to add value to local products, and to improve human health.

Comparative analysis of fatty acids, tocopherols and phytosterols content in sunflower cultivars (Helianthus annuus) from a three-year multi-local study

Sunflower oil is naturally rich in both unsaturated fatty acids and numerous minor components, with high levels of &-tocopherol and phytosterols that could play an important role in plant protection. These micronutriments, tocopherols and phytosterols, also exhibit health benefits for humans including reducing both cardiovascular diseases and aging disorders. &−Tocopherol represents more than 95% of total sunflower tocopherol and has the greatest vitaminic activity. Furthermore, this oil contains high amounts of β-sitosterol which is a promising health beneficial phytosterol. The objective of this study was to compare the content and composition of fatty acids, tocopherols and phytosterols in sunflower oil between different cultivars and locations in a three-year experiment, and to estimate the relationships between these minor components, fatty acids and climatic conditions. Results revealed that content and composition of these molecules are mainly determined by plant genotype. Nevertheless, the environmental conditions seemed to strongly influence the tocopherol content. The results suggest possible improvement in sunflower breeding for minor components.

Variation in oil content, fatty acid and phytosterols profile of Onopordum acanthium L. during seed development

This study has determined oil, fatty acid (FA) and phytosterols content during the ripening of the Tunisian Onopordum acanthium L. seeds. In total, nine FAs and six phytosterols were identified. The main FAs were linoleic acid (0.18–8.06 mg/g of seed) followed by oleic acid (0.051–2.45 mg/g of seed), palmitic acid and stearic acid. Pentadecanoic acid was detected, for the first time, in unripe fruits and the two last stages of development were characterised by a relative abundance of erucic acid. Overall, β-sitosterol (34.5–77.79% of total sterols) was the major 4-desmethylsterols during maturation. The first episodes of growth were characterised by the best amounts of stigmasterol and campesterol, while stigmastanol and Δ7 sitosterol had quoted the semi-ripe and fully ripe fruits; however, cholesterol was absent. These findings are useful in understanding a potential new source of important natural compounds (Phytosterols and USFA) found in this fruit and when harvest should be undertaken to optimise desired FA and phytosterols content.

Physicochemical and Antioxidant Characteristics of Kapok (Ceiba pentandra Gaertn.) Seed Oil

AbstractIn view of the growing demand for vegetable oils and fats, currently exploration of some under‐utilized and non‐conventional oil seed crops is of great concern. This work presents data on the detailed physicochemical and antioxidant attributes of kapok (Ceiba pentandra Gaertn.) seed oil. The kapok seeds contained an appreciable amount of oil (27.5 %), protein (35.0 %) and fiber (19.0 %). The extracted kapok seed oil (KSO) had an iodine value of 101.8 g of I2/100 g of oil, a saponification value of 187 mg of KOH/g of oil), and unsaponifiable matter 0.83 %. KSO also showed a good oxidation state as indicated by the measurements of the peroxide value, conjugated dienes, conjugated trienes, para‐anisidine and the induction period (Rancimat method). The tested oil showed a considerable amount of total phenolics (2.50 mg/100 g) and an appreciable free radical scavenging capacity. Gas liquid chromatographic analysis of fatty acids (FA) reveals that KSO mainly has linoleic acid (33.6 %) followed by oleic acid (23.4 %) and palmitic acid (22.4 %). Besides, a notable amount of cyclopropenoid fatty acids such as malvalic acid (9.1 %) and sterculic acid (2.8 %) was also detected. The FA composition of the tested oil was further verified by recording FTIR and NMR spectra. Among the oil phytosterols, analyzed by GC/GC–MS, β‐sitosterol was found to be the principal component whereas RP‐HPLC analysis showed the occurrence of γ‐tocopherol (550 mg/kg) as the major tocopherol along with considerable amount of α‐tocopherol (91 mg/kg) and δ‐tocopherol (5.52 mg/kg). It can be concluded from the results of this comprehensive study that under‐utilized kapok seeds are a potential feed stock for the production of a useful oil for edible and/or oleochemical applications.

Profile of Bioactive Compounds in Avocado Pulp Oil: Influence of the Drying Processes and Extraction Methods

AbstractThe influence of different procedures of pulp drying and oil extraction methods on the concentrations of α‐tocopherol, squalene and several phytosterols in avocado oil was evaluated. Pulp portions of Fortune variety avocados were dried either by lyophilization or under circulating air at 40 or 70 °C. For lyophilization and for each air drying temperature, the oil was obtained either by cold pressing or with Soxhlet extraction using petroleum ether. The dehydrated pulp (73 % of the pulp weight) yielded 25–33 % oil by cold pressing, and 45–57 % oil by Soxhlet extraction. Infrared spectroscopy and gas chromatography with FID and mass spectrometry detection were used to analyze the oils. α‐Tocopherol, squalene, cycloartenol acetate, β‐sitosterol, campesterol and stigmasterol were present in all the oil samples. In comparison to lyophilization, hot air drying resulted in smaller concentrations of α‐tocopherol, squalene and β‐sitosterol, and larger relative concentrations of campesterol and cycloartenol acetate. On the other hand, extraction by cold pressing produced a smaller amount of oil, with greater concentrations of α‐tocopherol and squalene, and lower contents of campesterol and cycloartenol acetate, than Soxhlet extraction. Thus, the oil yield was maximal with lyophilization and Soxhlet extraction, but lyophilization and cold pressing produced oils which had greater concentrations of antioxidants and other bioactive compounds.

Quantitative Analysis of Phytosterols in Edible Oils Using APCI Liquid Chromatography–Tandem Mass Spectrometry

Previous methods for the quantitative analysis of phytosterols have usually used GC-MS and require elaborate sample preparation including chemical derivatization. Other common methods such as HPLC with absorbance detection do not provide information regarding the identity of the analytes. To address the need for an assay that utilizes mass selectivity while avoiding derivatization, a quantitative method based on LC-tandem mass spectrometry (LC-MS-MS) was developed and validated for the measurement of six abundant dietary phytosterols and structurally related triterpene alcohols including brassicasterol, campesterol, cycloartenol, β-sitosterol, stigmasterol, and lupeol in edible oils. Samples were saponified, extracted with hexane and then analyzed using reversed phase HPLC with positive ion atmospheric pressure chemical ionization tandem mass spectrometry and selected reaction monitoring. The utility of the LC-MS-MS method was demonstrated by analyzing 14 edible oils. All six compounds were present in at least some of the edible oils. The most abundant phytosterol in all samples was β-sitosterol, which was highest in corn oil at 4.35±0.03mg/g, followed by campesterol in canola oil at 1.84±0.01mg/g. The new LC-MS-MS method for the quantitative analysis of phytosterols provides a combination of speed, selectivity and sensitivity that exceed those of previous assays.

Characteristics of Biologically-Active Substances of Amaranth Oil Obtained by Various Techniques.

Amaranth seeds and their main product amaranth oil are a rich source of bioactive substances. The non-saponifi able substances which accompany lipids include: squalene, tocopherols, sterols and others. The aim of the study was to compare the content of squalene, tocopherols and phytosterols in amaranth oils obtained by various techniques. The oil was extracted from seeds (Amaranthus cruentus) with the use of supercritical fl uid extraction (SFE), extraction with a chloroform/methanol mixture and expeller pressing. Contents of squalene and tocopherols were determined with high performance liquid chromatography (HPLC) method. The content of sterols in oils was determined by gas chromatography coupled with mass spectrometry (GC-MS). The highest squalene content was found for the oil obtained as a result of supercritical CO 2 extraction (6.95 g/100 g of oil). A lower content of squalene was noted in the oil extracted with organic solvents and in cold-pressed oil – 6.00 and 5.74 g/100 g of oil, respectively. The amaranth oils were characterised by a signifi cant content of tocopherols. The oil obtained as a result of fl uid extraction was characterised by the highest content of tocopherols (131.7 mg/100 g of oil). A dominating homologue (40%) was β-tocopherol. Also the same sample was characterised by the highest content of sterols (2.49 g/100 g of oil). In all samples the predominating sterol was sum of α-spinasterol and sitosterol, which accounted for 45%, 56% and 53% of total analysed sterols for the oil obtained from SFE, from extraction with solvents and from cold pressing, respectively.