Fatty acids and lignans in unground whole flaxseed and sesame seed are bioavailable but have minimal antioxidant and lipid‐lowering effects in postmenopausal women

Fatty acids and lignans in ground flaxseed and sesame seed are absorbed, metabolized, and exert some health benefits in vivo. However, it is unclear if they are absorbed, metabolized, and exert health benefits when consumed as unground whole seed; therefore, it was investigated in this study. In a randomized crossover study, 16 postmenopausal women supplemented their diets with food bars containing either 25 g unground flaxseed, sesame seed, or their combination (12.5 g each) (flaxseed+sesame seed bar, FSB) for 4 wk each, separated by 4 wk washout periods. Total serum n‐3 fatty acids increased with flaxseed (p<0.05) and FSB (p=0.064) while serum n‐6 fatty acids increased with sesame seed (p<0.05). Urinary lignans increased similarly with all treatments (p<0.05). Plasma lipids and several antioxidant markers were unaffected by all treatments, except serum γ‐tocopherol (GT), which increased with both sesame seed (p<0.0001) and FSB (p<0.01). In conclusion, fatty acids and lignans from unground seed in food bars are absorbed and metabolized; however, except for serum GT, the 25 g unground seed is inadequate to induce changes in plasma lipids and several biomarkers of oxidative stress.     

Nutraceutical functions of sesame: a review

The results of recent food chemical and nutraceutical studies on the traditionally well-known health value of sesame are described, including some aspects of the utilization of sesame. The highly antioxidative activity of sesame oil was clarified and found to involve newly discovered lignans. The antiaging effect of sesame was elucidated to be due to the strong vitamin E activity caused by a novel synergistic effect of sesame lignans with tocopherols resulting from the inhibition of metabolic decomposition of tocopherols by sesame lignans. The specific inhibitory action of sesame lignans on Delta5 desaturase in polyunsaturated fatty acid synthesis was found in studies on the microbial production of polyunsaturated fatty acids. This effect of sesame lignans was extended to various effects on fatty acid metabolism involving lowering fatty acid concentration in liver and serum due to acceleration of fatty acid oxidation and suppression of fatty acid synthesis, and the controlling influence on the ratio of n-6/n-3 polyunsaturated fatty acids under excess intake of either n-6 or n-3 fatty acids in the diet. Sesame lignans lowered the cholesterol concentration in serum, especially in combination with tocopherol, due to the inhibition of absorption from the intestine and suppression of synthesis in the liver. Sesame lignans also showed other useful functions such as acceleration of alcohol decomposition in the liver, antihypertensive activity, immunoregulatory activities, anticarcinogenic activity, and others.     

The fatty acid and tocopherol constituents of the seed oil extracted from 21 grape varieties (Vitis spp.)

BACKGROUND: Fatty acids and tocopherols in appropriate quantities are invaluable attributes that are desirable in seeds of agricultural products. Studies have generally focused on the evaluation of the oil and tocopherol components of oil crops. Recently, investigations revealed that the grape seed has robust potential in the production of healthy fatty acids as well as tocopherols. This study was thus conducted to determine the oil and tocopherol components of grape seeds, obtained from various grape cultivars of different species, including two rootstock varieties. RESULTS: The grape seed oil concentration of the studied varieties ranged from 7.3 to 22.4%. The determined fatty acid profiles of the genotypes conformed to the pattern described in the literature for grapes. Linoleic acid is the major component comprising 53.6–69.6% of the total, followed by oleic (16.2–31.2%), palmitic (6.9–12.9%) and stearic (1.44–4.69%). The oils of all the seeds analysed showed a preponderance of α‐tocopherol (ranging from 260.5 to 153.1 mg kg^?1 oil extract). β‐Tocopherol, γ‐tocopherol and δ‐tocopherol were also detected with the general means of 0.98, 22.2 and 0.92 mg kg^?1, respectively. Linoleic acid showed a significantly negative correlation with all the fatty acids analysed. The strongest negative correlation existed between linoleic and oleic acids (r = ? 0.834, P < 0.01). CONCLUSION: Present investigations indicated that oil content, fatty acid composition and tocopherol constituents of grape seed show great variation among the genotypes. Markedly higher proportions of linoleic acid with considerable amounts of tocopherols found in the oil samples suggest that grape seed is a good source for culinary, pharmaceutical and cosmetic uses. Copyright © 2012 Society of Chemical Industry     

A Chemometric Approach to Assess the Frying Stability of Cottonseed Oil Blends During Deep-Frying Process: Fatty Acid Composition and Tocopherol Analyses

The aim of the present study was to determine impacts of different additives on fatty acid composition and total tocopherol content of cottonseed oil during deep-frying process using a chemometric approach. A quarter-fractional factorial design with two levels and five factors was used for preparing the frying cottonseed oil blends. In the experimental design, additives were such as ascorbic palmitate, mixed tocopherols, dimethylpolysiloxane, lecithin, and sesame oil were used as factors. The effect of additives on fatty acid composition and tocopherol content were evaluated with normal distribution (ND) graphs during ten hours frying at 170 ± 5°C. The data were statistically assessed by one-way analysis of variance at a significance level of p < 0.05. The analysis of variance test results were in good agreement with ND graphs and data indicated that the interaction between ascorbic palmitate and dimethylpolysiloxane (A × C factor) showed a significant and protective effect on fatty acids. Meanwhile, the sesame oil (E factor) and A × C factor were showed a significant effect on level of tocopherols. The results of study indicated that present approach could be used to assess and improve the frying stability of any oil with respect to fatty acid composition and tocopherols.     

Variation of sesamin,sesamolin and tocopherols in sesame (Sesamum indicum L.) seeds and oil products in Thailand

Sesame (Sesamum indicum L.) seed and oil contain abundant lignans, including sesamin, sesamolin and lignan glycosides. The aim of the present study was to determine sesamin, sesamolin and tocopherol contents in sesame seed and oil available in Thailand. The results showed that there was a large variation of sesamin and sesamolin contents in products. The distribution plot of sesamin and sesamolin contents in seeds showed that the mean values of sesamin and sesamolin were 1.55 mg/g (SD = 1.63; range n.d.–7.23 mg/g) and 0.62 mg/g (SD = 0.48; range n.d.–2.25 mg/g), respectively. The range of total tocopherols of these sesame lines was 50.9–211 μg/g seed. In commercial sesame oils, the ranges of sesamin and sesamolin were 0.93–2.89 mg/g oil and 0.30–0.74 mg/g oil, respectively, and tocopherol contents were 304–647 μg/g oil. The study reveals the extensive variability in sesamin, sesamolin and tocopherol contents among sesame products.     

Effects of Sesame Oil Addition to Soybean Oil During Frying on the Lipid Oxidative Stability and Antioxidants Contents of the Fried Products During Storage in the Dark

ABSTRACT: Effects of sesame oil addition to soybean oil during frying on the lipid oxidative stability and antioxidants contents of fried products during storage in the dark were studied. Flour dough pieces (2 cm × 2 cm × 0.1 cm) were fried at 160 °C for 1 min in sesame oil-added soybean oil. Concentrations of sesame oil in the frying oil were 0%, 10%, and 20% by volume. Fried products were put into a glass bottle, and the bottles were tightly sealed and stored at 60 °C in the dark for 18 d. Lipid oxidation of fried products was determined by fatty acid composition changes and conjugated dienoic acid (CDA) and p -anisidine (PA) values. Tocopherols and lignan compounds in the fried products were determined by high-performance liquid chromatography. Relative content of linolenic acid decreased, and CDA and PA values increased during storage of the fried products in the dark. Fatty acid composition change and CDA and PA values during storage were lower in the products fried in sesame oil-added soybean oil than in the products fried in soybean oil without sesame oil. The results clearly showed that addition of roasted sesame oil to soybean oil at 10% and 20% during frying decreased the lipid oxidation of fried products during storage in the dark for 18 d by extension of induction period and decrease in decomposition of oxidized lipids. Fried products contained 134 to 267 ppm tocopherols and 0 to 148 ppm lignans before storage; however, their contents decreased during storage in the dark. Lignan compounds were more stable than tocopherols, and the rate of tocopherols degradation was lower in the products fried in sesame oil-added soybean oil than in the products fried in soybean oil without sesame oil, which could be because of protection of tocopherols from degradation by lignan compounds.     

Impact of Roasting on the Chemical Composition and Oxidative Stability of Perilla Oil

Abstract: The impact of roasting was observed with regard to certain changes in the chemical components and oxidative stability of oil expelled from the roasted perilla seeds. The roasting times were established differently at each roasting temperature of 180, 200, and 220 °C. Trans fatty acids in perilla oil were detected, and the level detected increased as the roasting time increased. Moreover, the roasting of perilla seed led to an increase of 4 tocopherols, α‐, β‐, γ‐, and δ‐tocopherol, as well as phosphorus in the oil. The oxidative stability of the oils obtained after roasting increased during 60 d of storage at 60 °C. The rate of decrease of tocopherol in the oil from unroasted perilla seed was faster than that of the tocopherol in the oils from roasted perilla seeds during storage. Practical Application: The results reported in present research provide useful information that the producers of perilla oil could apply for their processing.     

Changes of bioactive components in berry seed oils during supercritical CO2 extraction

The objective of the work was to elucidate the chemical composition of fractions of oil extracts obtained during the supercritical extraction on a semi‐industrial scale from strawberry (Fragaria x ananassa Duch.), chokeberry [Aronia melanocarpa (Michx.)], and raspberry (Rubus idaeus L.) seeds from industrial press cake. The oil extracts differed in terms of their content of bioactive components: carotenoids, tocopherols, chlorophylls, and fatty acids. Raspberry seed oil was the richest source of tocopherols (620.1–2166.7 mg kg^?1) and α‐linolenic acid (above 37%). Chokeberry seed oil had the highest content of linoleic acid (above 70%), and α‐tocopherol (166.0–1104.8 mg kg^?1). Strawberry oil was characterized by the highest content of chlorophylls and α‐linolenic acid (above 30%). It was showed that the oil fraction collected at the beginning of extraction is characterized by a high acid value, which requires purification steps to be used for food purposes.

Practical applications

Strawberry, raspberry, and chokeberry by‐products left over from the production of concentrated juice are a valuable source of oils rich in n‐3 and n‐6 polyunsaturated fatty acids, tocopherols, and carotenoids. The research showed that the fractionation of extracts in the course of supercritical extraction leads to oils with varying amounts of different bioactive compounds, and thus to products with potentially wide applications. Seeds oils have high potential utility as a source of unconventional oil for cosmetic and pharmaceutical sectors and biodiesel. Their targeted utilization may be exploited for economic, environmental and health benefits.     

基于脂肪酸和生育酚组成的油茶籽油掺假判别可行性分析

从脂肪酸和生育酚的组成分析以及所得色谱数据的系统聚类分析(HCA)和主成分分析(PCA)方面考察了10种植物油的异同点。气相色谱分析10种植物油的脂肪酸组成,鉴别得到12种脂肪酸。对脂肪酸组成数据的HCA分析结果表明,油茶籽油与橄榄油和菜籽油具有相似的脂肪酸组成,而与其他植物油的脂肪酸组成差异显著;而PCA分析结果可以进一步区分油茶籽油与橄榄油和菜籽油。高效液相色谱分析10种植物油的生育酚组成,测得4种异构体的相对含量。对生育酚组成数据的HCA、PCA分析结果表明,油茶籽油和菜籽油的生育酚组成差异显著。因此,基于脂肪酸和生育酚组成分析可以作为油茶籽油掺假判别的依据。     

Effect of Infrared Heating on the Formation of Sesamol and Quality of Defatted Flours from Sesamum indicum L.

ABSTRACT:  Infrared (IR) heating offers several advantages over conventional heating in terms of heat transfer efficiency, compactness of equipment, and quality of the products. Roasting of sesame seeds degrades the lignan sesamolin to sesamol, which increases the oxidative stability of sesame oil synergistically with tocopherols. IR (near infrared, 1.1 to 1.3 μm, 6 kW power) roasting conditions were optimized for the conversion of sesamolin to sesamol. The resultant oil was evaluated for sesamol and tocopherol content as well as oxidative stability. The defatted flours were evaluated for their nutritional content and functionality. IR roasting of sesame seeds at 200 °C for 30 min increased the efficiency of conversion of sesamolin to sesamol (51% to 82%) compared to conventional heating. The γ-tocopherol content decreased by 17% and 25% in oils treated at 200 and 220 °C for 30 min, respectively. There were no significant differences in the tocopherol content and oxidative stability of the oil. Methionine and cysteine content of the flours remained unchanged due to roasting. The functional properties of defatted flours obtained from either IR roasted or conventionally roasted sesame seeds remained the same.
Practical Applications: Sesame oil is stable to oxidation compared to other vegetable oils. This stability can be attributed to the presence of tocopherols and the formation of sesamol, the thermal degradation product of sesamolin—a lignan present in sesame. Roasting of sesame seeds before oil extraction increases sesamol content which is a more potent antioxidant than the parent molecule. The conversion efficiency of sesamolin to sesamol is increased by 31% by infrared roasting of seeds compared to electric drum roasting. This can be used industrially to obtain roasted oil with greater oxidative stability.     

Progress in modification of sunflower oil to expand its industrial value

Increasing the sunflower seed oil content as well as improving its quality makes it compatible for industrial demands. This is an important breeding objective of sunflower which increases its market value and ensures high returns for the producers. The present review focuses on determining the progress of improving sunflower seed oil content and modifying its quality by empirical and advanced molecular breeding methods. It is known that the sunflower oil content and quality have been altered through empirical selection methods and mutation breeding programmes in various parts of the world. Further improvement in seed oil content and its components (such as phytosterols, tocopherols and modified fatty acid profile) has been slowed down due to low genetic variation in elite germplasm and complex of hereditary traits. Introgression from wild species can be carried out to modify the fatty acids profile and tocopherol contents with linkage drags. Different transgenes introduced through biotechnological methods may produce novel long‐chain fatty acids within sunflower oil. Bio‐engineering of sunflower oil could allow it to be used in diverse industrial products such as bio‐diesel or bio‐plastics. These results showed that past and current trends of modifying sunflower oil quality are essential for its further expansion as an oilseed crop. © 2017 Society of Chemical Industry     

Composition and oxidative stabilities of oils extracted from hybrid hazelnuts grown in Nebraska,USA

Recently, hybrid hazelnuts have emerged as a potential oilseed crop in Nebraska for food and value‐added industrial applications. As with all hazelnuts, Nebraska hybrid hazelnuts were characterised by the high oil content with the average oil content of 54.3%. Oleic acid was the predominant fatty acid. Oleic acid and linoleic acid accounted for more than 90% of the total fatty acid composition, whereas small quantities of palmitoleic and linolenic acids were found. Four major tocopherols (α‐, β‐, γ‐ and δ‐tocopherols) were identified with α‐tocopherol as the most dominant isomer. The average total tocopherol content was 235.4 mg kg^?1 oil with α‐tocopherol constituting approximately 97.5% of the total tocopherols. β‐sitosterol was the most abundant sterol of the three identified sterols representing, on average, 93.1% of total sterols, followed by campesterol and stigmasterol. The oil oxidative stability was affected by the presence of high levels of natural antioxidants and monounsaturated fatty acids (MUFA). Genotype 16–177 was superior to the other genotypes, when combining high levels of MUFA, tocopherols and phytosterols, and high oxidative stability.     

Chemical Composition and Antioxidant Capacity of Brazilian Passiflora Seed Oils

The seed oils of different varieties of 4 Passiflora species cultivated in Brazil were analyzed and compared regarding their physicochemical parameters, fatty acid composition and the presence of minor components, such as phytosterols, tocopherols, total carotenoids, and phenolic compounds. The antioxidant capacities of the oil extracts were determined using the 2,2'azinobis [3‐ethylbenzothiazoline‐6‐sulfonic acid] and oxygen radical absorbance capacity methods. The results revealed that all studied Passiflora seed oils possessed similar physicochemical characteristics, except for color, and predominantly contained polyunsaturated fatty acids with a high percentage of linolenic acid (68.75% to 71.54%). Other than the total phytosterol content, the extracted oil from Passiflora setacea BRS Pérola do Cerrado seeds had higher quantities (% times higher than the average of all samples), of carotenoids (44%), phenolic compounds (282%) and vitamin E (215%, 56%, 398%, and 100% for the α‐tocopherol, β‐tocopherol, γ‐tocopherol, and δ‐tocopherol isomers, respectively). The methanolic extracts from Passiflora setacea BRS Pérola do Cerrado seed oil also showed higher antioxidant activity, which was positively correlated with the total phenolic, δ‐tocopherol, and vitamin E contents. For the first time, these results indicate that Passiflora species have strong potential regarding the use of their seeds for oil extraction. Due to their interesting composition, the seed oils may be used as a raw material in manufacturing industries in addition to other widely used vegetable oils.     

微波预处理对芝麻油中芝麻木酚素含量及油脂品质的影响

为了确定高芝麻酚芝麻油的最适微波预处理条件,将芝麻水分含量调节为5个梯度,在不同微波预处理时间下制得芝麻油样品,对其芝麻木酚素含量、酸值、茴香胺值、氧化诱导时间、脂肪酸组成、生育酚含量、有害物质（多环芳烃和杂环胺）含量及感官品质进行了分析,探究芝麻水分含量和微波预处理时间对芝麻油中芝麻木酚素含量及油脂品质的影响。结果表明：微波预处理时间6 min、芝麻水分含量7%条件下制得的芝麻油芝麻酚含量较高,芝麻油酸值符合国家标准限定要求,氧化稳定性较强,有害物质杂环胺和多环芳烃含量处于适当的可控水平,同时兼顾了芝麻油的固有风味,消费者的喜爱度较高。综上,高芝麻酚芝麻油的最适微波预处理条件为微波预处理时间6 min,芝麻水分含量7%。     

The use of sesame oil unsaponifiable matter as a natural antioxidant

Individual components of sesame oil unsaponifiable matter isolated from two different coloured seed varieties (white and brown) were identified and quantified. Unsaponifiables from the brown sesame variety were markedly different in their composition from those of the white variety. The brown variety contained higher amounts of total sterols and tocopherols but lower amounts of sesamin, sesamolin and total hydrocarbons than the white variety. The seeds were roasted at 180 °C for 30 min. Roasting increased some effective antioxidant compounds. These included relatively higher percentages of sesamol, Δ^24,28 ethylidene sterols (Δ⁵ and Δ⁷-avenasterols), squalene, as well as tocopherols and some active browning substances. These antioxidative components are effective via synergistic action. Additionally, unsaponifiable matter from unroasted (USM) and roasted white sesame seeds (RSM) was added individually to sunflower oil at levels of 0.02, 0.05 and 0.1% and their effectiveness was compared with a control (no additives) at 63 °C. Results indicated that both USM and RSM had antioxidant activity which increased with increasing concentration. Compared to USM, the RSM was a better antioxidant in most cases. Moreover, the addition of 0.1% RSM gave a strong antioxidative efficiency and this could be used as an alternative natural antioxidant for food applications.     

The changes of chemical composition of microencapsulated roselle (Hibiscus sabdariffa L.) seed oil by co-extrusion during accelerated storage

Roselle seed oil (RSO) is an underutilised seed oil, which is having beneficial properties to humans. Microencapsulation of vegetables and seed oil is an alternative to preserve these properties and deliver them to the human diet. In this study, microencapsulation of RSO was performed using co-extrusion technology and 1.5% w/w sodium alginate solution with 1.5% w/w high methoxyl pectin as the wall materials. Results showed that the microencapsulation efficiency was high (95.68 ± 1.95%) and the microencapsulation indeed preserved the content of unsaturated fatty acids, phytosterols, and tocopherols. During an accelerated storage condition at 65 °C for 24 days, most of these properties remained high for the first six storage days, including tocopherol which preserved high γ-tocopherol. Worth noting that the microencapsulated RSO (MRSO) was particularly effective in preserving the total unsaturated fatty acids (especially C18:1 and C18:2), even during the 24th day of storage. The total unsaturated fatty acids retained by MRSO were significantly (P < 0.05) higher (70 ± 0.4%) than the RSO (65.6 ± 1.6%). In short, microencapsulation was effective in preserving the RSO properties.     

Lipid oxidation-related characteristics of gim bugak (Korean fried cuisine with <Emphasis Type="Italic">Porphyra</Emphasis>) affected by frying oil

The effect of frying oil on the lipid oxidation, antioxidants, and in vitro antioxidant activity of gim bugak was studied. Bugak was prepared by pan-frying at 180 °C in unroasted sesame, soybean, extra virgin olive, or palm oil. The degree of lipid oxidation based on conjugated dienoic acid and p-anisidine values was higher in the bugak fried in soybean or sesame oil with high contents of polyunsaturated fatty acids and tocopherols. However, the oil oxidation was lower in olive and palm oils, which showed higher degradation of tocopherols and polyphenols than in sesame or soybean oil during frying. Although the bugak fried in palm oil contained less antioxidants than that fried in soybean or sesame oil, the in vitro antioxidant activity was not different (p > 0.05). Results suggest that palm oil can replace unroasted sesame oil for the preparation of gim bugak with improved lipid oxidative stability and health functionality.     

Oxidative Stability of Soybean and Sesame Oil Mixture during Frying of Flour Dough

ABSTRACT: Effects of roasted sesame seed oil on the oxidative stability of soybean oil during frying of flour dough at 160 °C were studied by determining fatty acid composition and conjugated dienoic acid (CDA), p -anisidine (PA), and free fatty acid (FFA) values. Concentration of sesame oil in frying oil was 0%, 10%, 20%, or 30% (v/v). Tocopherols and lignan compounds in the frying oil were also determined by high-performance liquid chromatography. As the number of fryings performed by the oil increased, linolenic acid content in frying oil decreased, and the decreasing rate was lower in frying oil containing sesame oil than in the oil containing no sesame oil. CDA and FFA values of frying oil increased during frying and their relative values to the initial value were lower in frying oil containing sesame oil than in the oil containing no sesame oil. This indicates that the addition of sesame oil improved thermooxidative stability of frying oil, possibly due to the presence of lignan compounds in sesame oil. Tocopherols and lignan compounds in frying oil decreased during frying. As the amount of sesame oil in frying oil increased, degradation of tocopherols increased and lignan compounds degradation decreased. Tocopherols were suggested to protect lignan compounds in sesame oil from decomposition during frying.     

不同加热条件对油茶籽油品质影响的研究

以油茶籽油为原料,研究不同加热处理对油脂的脂肪酸、生育酚、角鲨烯含量的影响。结果表明：油茶籽油中油酸含量随温度的升高及加热时间的延长而增加;不饱和脂肪酸含量总体随加热时间的延长呈上升趋势,饱和脂肪酸含量随加热时间的延长呈下降趋势。高温或长时间加热均导致角鲨烯和生育酚含量的损失。加热后油茶籽油总生育酚平均含量为43.68 mg/kg,较未加热(88.96 mg/kg)降低了50.90%;加热后角鲨烯平均含量为64.15 mg/kg,较未加热(67.06 mg/kg)降低了4.34%。