Bioactive lipids and fatty acids profile of Cistanche phelypaea

Oil extracted from the wild plant of Cistanche phelypaea was analyzed for its fatty acid, sterol, hydrocarbon and tocopherol contents. Total lipids (TL) content was 10 g/kg (on dry weight basis). The majority of fatty acids were of the unsaturated type (50.4 % of total fatty acids), while the saturated (mainly palmitic acid) were about 43.2 % of the total fatty acids. Oleic acid was the dominating fatty acid followed by palmitic and linoleic acids. High amounts of sterols were found in the oil with the main component β-sitosterol. Other phytosterols (e.g. stigmasterol, ∆⁷-avenasterol and ∆⁵-avenasterol) were present at approximately equal amounts (6–9 % of total sterols). The main identified hydrocarbon compounds were C₂₁, C₂₆ and C₃₂ constituting about 61.2 % of total hydrocarbons. Small amounts of C₁₂, C₁₈ and C₂₂, however, were also detected. Tocopherol levels were high in the oil (3.36 g/kg oil), wherein β-tocopherol was the main component followed by α-isomer. Both tocopherol components comprised more than 87 % of total vitamin E content in the oil. Furthermore, γ- and δ-tocopherols were detected in small amounts in the oil accounting for 14–16 % of the total vitamin E content. Information provided by the present work will be of importance for food applications and chemotaxonomy of Cistanche phelypaea.     

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.     

The composition of acyl lipids and tocopherols in wheat germ oils from various sources

The compositions of acyl lipids, fatty acids and tocopherols were determined for a series of laboratory-extracted and commercial wheat germ oils and a comparison made of the total carotenoid contents. High-performance liquid chromatography (h.p.l.c.) with fluorescence detection was used to determine tocopherols and tocotrienols without the need for pretreatment of the oils. The laboratory-extracted oils were similar in composition except for the content of free fatty acids and the β-tocotrienol derived from bran in the unpurified mill germ; carotenoid content was lower in oil from rancid or cooked germ. The commercial oils contained very low concentrations of carotenoids and polar lipids and three samples had unusual tocopherol compositions very different from those of the laboratory-extracted oils. One of these samples contained no detectable amount of linolenic acid which is usually present in cereal oils. It is concluded that the quality and composition of commercial wheat germ oil is very variable and that methods of assessing quality and detecting adulteration are essential. H.p.l.c. with fluorescence detection is well-suited to the analysis of tocopherols, tocotrienols and α-tocopherol acetate in wheat germ oil.     

Comparison of Oxidative Stability among Edible Oils under Continuous Frying Conditions

The stability of camellia oil (saturated fatty acid: monounsaturated fatty acid: polyunsaturated fatty acid = 1:7:1) after frying potatoes was compared with palm oil (saturated fatty acid: monounsaturated fatty acid: polyunsaturated fatty acid = 4:4:1) and peanut oil (saturated fatty acid: monounsaturated fatty acid: polyunsaturated fatty acid = 2:4:4). Oil samples were evaluated for acid value, iodine value, peroxide value, p-anisidine value, total oxidation value, tocopherols content, and fatty acids composition. There was the least change in fatty acid composition in camellia oil among the three edible oils. The α-tocopherol was more vulnerable to heat degradation than γ-tocopherol and δ-tocopherol, and α-tocopherol was completely degraded before the whole frying process was done for palm and peanut oils. The oxidative stabilities of the three edible oils were in the order of camellia oil > palm oil > peanut oil. The oxidative stability was mainly determined by the calculated oxidizability value related to fatty acid composition, and when calculated oxidizability values were similar, the tocopherol contents of edible oils would be a key factor in affecting their oxidative stabilities.     

Gamma-irradiation as a method of microbiological control,and its impact on the oxidative labile lipid component of <Emphasis Type="Italic">Cannabis sativa</Emphasis> and <Emphasis Type="Italic">Helianthus annus</Emphasis>

The effect of irradiation (0–20 kGy) on hemp and sunflower seeds was assessed, with specific reference to the oxidatively labile lipid component (unsaturated fatty acids and tocochromanols). Total protein, lipid, and solids content of the seeds did not vary with irradiation dose. Lipid hydroperoxide concentration increased significantly in the sunflower seeds (48 mmol kg⁻¹ lipid) and a significant increase in volatile secondary oxidation products was measured in both seeds (e.g. hexanal, heptanal, 1-penten-3-ol) with increasing irradiation dose. Irradiation at 5 kGy sterilised the seeds of all microbial contamination and irradiation doses of 20 kGy prevented germination. A loss of the antioxidant tocopherol was shown with increasing irradiation doses, although this was selective for specific tocopherol isoforms (α-tocopherol, β-tocopherol and γ-tocopherol).     

Seed oils of ten traditional Portuguese grape varieties with interesting chemical and antioxidant properties

To increase the potential and better exploring of grape seeds that are an important wine-industrial waste, oils of ten traditional Portuguese grape varieties were evaluated in relation to their vitamin E content (tocopherols and tocotrienols), fatty acid profile, as well as, antioxidant properties. Our results showed that the grape-seed oils were a good source of γ-tocotrienol (499–1575 mg/kg), α-tocopherol (85.5–244 mg/kg) and α-tocotrienol (69–319 mg/kg). Concerning fatty acid profile, linoleic (C18:2cc), oleic (C18:1), palmitic (C16:0) and stearic (C18:0) acids were the predominant. Grape-seed oils demonstrated to be a good source of polyunsaturated fatty acids (PUFAs) (63.64–73.53%), whereas monounsaturated fatty acid (MUFA) and saturated fatty acid (SFA) ranged between 14.19–21.29% and 11.64–14.94%, respectively. Interesting values of DPPH and ABTS radical scavenging activities were also obtained. This study demonstrated that these seeds may be reused and their oils incorporated in other food products, taking into account the compounds with positive effects on human health that are present in their composition.     

Tocopherols and tocotrienols as free radical-scavengers in refined vegetable oils and their stability during deep-fat frying

The aim of this study was to assess the effect of total tocopherols and tocotrienols of refined vegetable oils on oil radical-scavenging activity and to investigate the stability of the various homologues during the deep-fat frying of French fries. Eight different refined vegetable oils were investigated, having variable levels of natural tocopherols and tocotrienols. A direct correlation between the radical-scavenging capacity of the oils, measured by the DPPH test, and the total content of natural tocopherols and tocotrienols was found. Frying experiments showed that the stability of the different tocopherols and tocotrienols present in the refined vegetable oils basically depend on two factors: the fatty acid composition of the oil, in particular polyunsaturated fatty acid content, and the kind of tocopherol and tocotrienol homologues present. The more oxidizable the oil, on the basis of fatty acid composition, the more stable were the tocopherolic antioxidants. Among the different homologues, γ-tocotrienol in palm super olein proved to be the least stable during the deep-fat frying, thus preserving the other homologues.     

Proximate composition and vitamin E levels in egg yolk: losses by cooking in a microwave oven

The proximate composition, fatty acid and tocopherol levels of egg yolk were determined in raw eggs and after different cooking processes: boiling for 3 and 10 min, heating in a microwave oven, and frying. Of the protein, lipid, ash and moisture contents, only the last decreased with microwave cooking. The predominant fatty acid was oleic (18:1) (36.10–42.6%), followed in decreasing amounts by palmitic (16:0), linoleic (18:2), linolenic (18:3) = arachidonic(20:4) = docosanoic (22:0), docosahexanoic (22:6) and myristic acid (14:0). Of the polyunsaturated fatty acids, 18:2, 18:3, 20:4 and 22:6 decreased in the samples subjected to microwaves. α-Tocopherol (6.1–2.9 mg per 100g) was the predominant isomer in all the samples followed by (β + γ)-tocopherol and δ-tocopherol, while α-tocotrienol was detected in trace amounts. All these tocopherols were reduced during cooking by up to 50% in omelettes and microwave treatments. © 1999 Society of Chemical Industry     

FATTY ACIDS AND TOCOPHEROL CONTENTS OF SOME PRUNUS SPP. KERNEL OILS

The oil content as well as the fatty acid and tocopherol composition of kernels from 15 Prunus spp. varieties from Turkey were determined. The oil yields from these kernels varied from 46.3 to 55.5%. The main fatty acids of Prunus spp. kernel oils were oleic acid (43.9–78.5%), linoleic acid (9.7–37%) and palmitic acid (4.9–7.3%). The total amount of vitamin-E-active compounds in the oils varied between 62.9 and 439.9 mg/kg. The predominant tocopherol in most kernel oils was γ-tocopherol. Only two varieties of P. amygdalus and one variety of P. persica showed α-tocopherol as the main vitamin-E-active compound. The composition of the oils was 9–164.5 mg/kg α-tocopherol, 21.5–41.6 mg/kg α-tocotrienol, 1.6–330.2 mg/kg γ-tocopherol and 0–39.1 mg/kg δ-tocopherol. From the results of the present study, it can be concluded that the kernels of the investigated species of Prunus fruits from Turkey may serve potential sources of valuable oil that might be used for edible and other industrial applications.

PRACTICAL APPLICATIONS

The search for new sources of vegetable oils is an ongoing challenge and the further utilization of by-products from the food processing industry is an interesting option in this field. Seed oils from Prunus species contain high amounts of recommended monounsaturated oleic acid moderate contents of linoleic acid and low amounts of saturated fatty acids that may result in more favorable oil than olive oil with regard to their fatty acid compositions. Additionally, the oils contain vitamin-E-active compounds. Both fatty acid composition and vitamin-E-active compounds may justify the further processing of seeds from Prunus species for the production of oil for food and pharmaceutical applications.     

Antiradical and antimicrobial properties of cold-pressed black cumin and cumin oils

Cold-pressed black cumin seed oil (BCSO) and cumin seed oil (CSO) were evaluated for their fatty acid profiles, phytosterol and tocopherol contents, antiradical properties and inhibition of microbial growth. The main fatty acids in BCSO were linoleic followed by oleic and palmitic acids. Petroselinic acid (C18:1n-12) was the main fatty acid in CSO, while linoleic acid was the second major unsaturated acid. Six sterol compounds were measured in BCSO and CSO, wherein the sterol marker was β-sitosterol. α-Tocopherol constituted 45% of tocopherols in BCSO, while β-tocopherol was the main component in CSO. BCSO and CSO oils had higher antiradical action against DPPH· and galvinoxyl radicals than virgin olive oil. Antimicrobial properties of BCSO and CSO were studied, and the results revealed that CSO inhibited the growth of all microorganisms tested, while BCSO inhibited the growth of all microorganisms tested except A. niger and A. flavus. BCSO and CSO had a drastic effect on the biosynthesis of protein and lipids in cells of B. subtilis.     

PREPARATION OF TOCOPHEROL SUCCINATES FROM DEODORIZER DISTILLATE

Preparation of tocopherol succinates from deodorizer distillate (DOD) with or without pretreatment was studied. To reduce damage to tocopherols, the reaction mixture was purged with nitrogen during heating. For DOD as a raw material, the succinylation procedure for converting tocopherols to tocopherol succinates was optimized in terms of type of catalyst, reaction time, and reaction temperature. Potassium acetate performed best among the catalysts tested. Using potassium acetate, 90% conversion was achieved within 30 min for total tocopherols and within 90 min for α-tocopherol. The optimal reaction time ranged from 60 to 90 min. To obtain rapid reaction and high conversion, the suitable temperature range was 100–140C. Under optimal conditions, a conversion of 93% was reached. For sterol-removed DOD as a raw material, the succinylation reaction was carried out at 140C for 1 h using potassium acetate as a catalyst. When using 10% of succinic anhydride and 1.3% of catalyst, over 80% of total tocopherols were converted to tocopherol succinates with conversion of α-tocopherol being highest among all isomers (over 90%). The conversion was significantly increased to over 90% by increasing the amount of succinic anhydride from 10 to 13% and that of the catalyst from 1.3 to 2%. Meanwhile, the free fatty acid (FFA) content was increased to approximately 10% after the succinylation reaction.     

The most important bioactive components of cold pressed oil from different pumpkin (Cucurbita pepo L.) seeds

The composition and content of certain bioactive components of the cold pressed oil obtained from six samples of pumpkin seeds (Cucurbita pepo L.) cultivated in Serbia were analyzed by GC and GC/MS. The composition and content of fatty acids, tocopherols and phytosterols, and the total content of squalene were determined. The results indicate oil's excellent quality, with high contents of monounsaturated fatty acids (37.1 ± 0.70–43.6 ± 0.69 g/100 g of total fatty acids), total tocopherols (38.03 ± 0.25–64.11 ± 0.07 mg/100 g of oil), sterols (718.1 ± 6.1–897.8 ± 6.8 mg/100 g of oil) and especially squalene (583.2 ± 23.6–747 ± 16 mg/100 g of oil). High content of squalene, phytosterols and monounsaturated fatty acids recommend the use of this type of the oil in the nutritional and medical purposes.     

Effect of rosemary on lipid oxidation in pressure-processed,minced chicken breast during refrigerated storage and subsequent heat treatment

The protective effect of rosemary (Rosmarinus officinalis L.) against lipid oxidation and tocopherol degradation in minced, pressure-processed chicken breast with 0.5% salt added was investigated during chill storage for 9 days and/or subsequent heat treatment by measurement of head-space hexanal and pentanal together with thiobarbituric acid reactive substances (TBARS) and α- and γ-tocopherol. High-pressure processing at 600 MPa for 10 min led to a significant increase in secondary lipid oxidation products in minced chicken breast without rosemary, when compared to chicken breast with rosemary added. During subsequent chill storage, the level of secondary lipid oxidation products decreased slightly. For samples heated after pressure treatment and chill storage to mimic cooking, levels of secondary lipid oxidation products were higher than for the uncooked samples and rosemary was very efficient in preventing the oxidative process also during cooking, while the length of the chill storage period prior to cooking had little effect. Higher levels of α- and γ-tocopherol were found in all samples with rosemary compared to samples without rosemary, indicating that rosemary also protects tocopherols against degradation in pressurized chicken breast during chill storage and/or subsequent heat treatment.     

Fatty acids,tocopherols and proanthocyanidins in bramble seeds

Studies were conducted on the fatty acids, tocopherols and proanthocyanidins in the seeds of 10 bramble varieties from China. The oil yields from these seeds vary from 4.81% to 15.72%. The main fatty acids in bramble seed oils are C18:2 n-6 (51.0–66.1%), C18:3 n-3 (9.70–35.6%), C18:1 n-9 (9.85–16.3%), and C16:0 (2.01–5.73%). The major tocopherol in all seed oils of 10 varieties was γ-tocopherol. The composition (mg/100 g) was as follows: α-tocopherol 7.65–52.6, γ-tocopherol 46.9–106, δ-tocopherol 3.1–9.50, and the active vitamin E 15.9–61.5 among the varieties. The total proanthocyanidin content varies from 6.81 to 17.6 mg/g. The main oligomers in total proanthocyanidins are dimers, and the least are trimers. The contents and composite proportions of fatty acids, tocopherols and proanthocyanidins are different according the varieties, which should be taken into account when the bramble seeds are exploited.     

我国不同产区核桃油组成成分与氧化稳定性研究

选取我国西南、西北和东部三大产区的 16 种薄皮核桃分别压榨制油,测定核桃油的脂肪酸组成、甘油三酯组成、总酚、生育酚、植物甾醇和氧化稳定性指数。结果表明,不同产区核桃油的脂肪酸组成主要为亚油酸 C18∶2(51.21%~68.97%),油酸 C18∶1(12.56%~26.04%),亚麻酸 C18∶3(6.82%~15.01%)和棕榈酸 C16∶0(3.05%~8.27%),甘油三酯包含三亚酸甘油酯 LLL(27.87%~39.47%)和油酸亚油酸亚麻酸甘油酯 OLLn(17.07%~24.18%)。微量伴随物植物甾醇,生育酚和总酚含量分别为 540~1 594 mg/kg,10~1 303 mg/kg,345~2 579 mg/kg。根据与其他国家和地区的核桃油比较,可以推断出不同的种植区域地理位置和气候的差异,导致了核桃油成分的差异。在此基础上将氧化稳定性指数与脂肪酸组成、微量伴随物含量进行多元线性回归分析后,得出亚油酸,α-生育酚和总酚是影响核桃油氧化稳定性的主要因素。     

A preliminary investigation into the unsaponifiable fraction of donkey milk: Sterols of animal origin,phytosterols, and tocopherols

We investigated the main sterols, phytosterols, and the α- and γ-tocopherol content in donkey milk during the first 2 mo of lactation. Cholesterol was the main sterol in milk (mean ± standard deviation = 0.97 ± 0.443 g/100 g of fat). Lanosterol was the main minor sterol of animal origin, followed by desmosterol (0.003 ± 0.001 and 0.001 ± 0.001 g/100 g of fat, respectively). Of the phytosterols, β-sitosterol was the main sterol of vegetal origin in donkey milk (0.005 ± 0.002 g/100 g of fat), but lower levels of campesterol, brassicasterol, and stigmasterol were also recorded. Mean levels of α- and γ-tocopherol were 0.01 ± 0.007 and 0.003 ± 0.001 g/100 g of fat, respectively. We observed no significant changes in sterol or tocopherol content during the first 2 mo of lactation. The presence of lanosterol in donkey milk is of particular interest, because lanosterol is a potential drug and has important physiological effects. The presence of phytosterols, which are considered nutraceutical molecules, enhances the nutritional quality of donkey milk fat for consumers.     

Effect of genotype and cultivation location on β-sitosterol and α-, β-, γ-, and δ-tocopherols in sorghum

This study aims to examine variations in β-sitosterol and α-, β-, γ-, and δ-tocopherol composition and content in sorghum grains with different genotypes and cultivation areas (Wonju and Miryang in Korea). β-Sitosterol content was found to be higher in Wonju sorghum; however, total tocopherol content was found to be higher in Miryang sorghum. Moreover, the β-sitosterol content did not correlate with physical characteristics, including 100-seed weight and color values (L, a, and b), but it was negatively correlated with total tocopherol content. β-Tocopherol was a major tocopherol in sorghum, constituting approximately 40%–46% of the total tocopherol content, and it was highly correlated with the total tocopherol content. Furthermore, the α-tocopherol content also increased with increasing γ-tocopherol content. Among the 4 tocopherols, only δ-tocopherol content correlated with physical characteristics of sorghum grain. This study deepened our knowledge of the variations in β-sitosterol and α-, β-, γ-, and δ-tocopherol content in sorghum with respect to genotype and cultivation location. In addition, this study demonstrated a correlation between some physical characteristics of sorghum and β-sitosterol/tocopherol content, and this information can be useful for breeding programs that develop or breed sorghum varieties or manufacture sorghum-based foods containing high amounts of β-sitosterol and tocopherols.     

Characterisation of fatty acids and bioactive compounds of kachnar (Bauhinia purpurea L.) seed oil

Information concerning the exact composition of kachnar (Bauhinia purpurea) seed oil is scare. In the present contribution, a combination of CC, GC, TLC and normal-phase HPLC were performed to analyse lipid classes, fatty acids and fat-soluble bioactives of kachnar seed oil. n-Hexane extract of kachnar oilseeds was found to be 17.5%. The amount of neutral lipids in the crude seed oil was the highest (ca. 99% of total lipids), followed by glycolipids and phospholipids, respectively. Linoleic, followed by palmitic, oleic and stearic, were the major fatty acids in the crude seed oil and its lipid classes. The ratio of unsaturated fatty acids to saturated fatty acid, was higher in neutral lipid classes than in the polar lipid fractions. The oil was characterised by a relatively high amount of phytosterols, wherein the sterol markers were β-sitosterol and stigmasterol. β-Tocopherol was the major tocopherol isomer with the rest being δ-tocopherol. In consideration of potential utilisation, detailed knowledge of the composition of kachnar (B. purpurea) seed oil is of major importance.     

Dietary phytosterols modify the sterols and fatty acid profile in a tissue-specific pattern

Phytosterol consumption reduces the absorption of dietary cholesterol and can alter the tissue fatty acid composition. The effects of manipulating sterol and phospholipid fatty acid profile by increasing levels of phytosterols (1000 and 4000 mg/kg diet) have been investigated in young Sprague–Dawley rats. Cholesterol levels decreased significantly only in liver, heart and skin. Significant increased levels of phytosterols were detected in all ten tissues analysed, with levels of campesterol in general being greater than those of β-sitosterol. The level of phytosterol incorporation ranged widely in tissues, more than doubling in heart, lung, spleen and erythrocytes to no significant increases in brain. In heart, kidney, spleen and lung there were dose dependent increases in phytosterol levels. The phospholipid fatty acid profile showed some small, but significant changes, but these were not consistent between tissues or for fatty acid classes. Dietary phytosterols accumulated differently in tissues and affected cholesterol levels and phospholipid fatty acid composition in a tissue-specific manner.     

Lipid characteristics and essential minerals of native Turkish hazelnut varieties (Corylus avellana L.)

Five native hazelnut varieties from Turkey, namely, prime quality Tombul variety, and second grade quality Yass? Badem, Sivri, Karaf?nd?k, and Ham varieties were examined for their lipid characteristics (triacylglycerol, tocopherol, tocotrienol, phytosterol, and phytostanol composition) and 12 essential minerals. Among 12 triacylglycerols separated in all hazelnut varieties, OOO (61.0–77.5%) and OOL (10.5–22.8%) were the main components (where O = oleoyl and L = linoleoyl). Seven tocol isoforms (four tocopherols and three tocotrienols), seven phytosterols, as well as cholesterol, and one phytostanol were positively identified and quantified; among these, α-tocopherol and β-sitosterol were predominant in all hazelnut oils. Hazelnut varieties served as an excellent source of copper and manganese. Consumption of the recommended daily amount of 42.5 g of hazelnut from different varieties provides 44.4–83.6% of copper and 40.1–448% of recommended manganese intake for adults. These results suggest that second grade quality hazelnut varieties were as good sources of functional lipids and essential minerals as was prime quality Tombul hazelnut, with some exceptions (P < 0.05).