Chemical characteristics of oils from naked and husk seeds of Cucurbita pepo L.

Pumpkin seed oils from naked and husk pumpkin seeds, produced by an industrial process and by laboratory extraction, were evaluated for fatty acid composition, tocopherol, sterol and squalene content. The major fatty acids in the oils from both varieties were oleic, linoleic and palmitic acid, followed by stearic acid. The ratios of monounsaturated to polyunsaturated fatty acids for husk and naked seed oils were about 0.60 and 0.75, respectively. Analysis of tocopherols in industrially pressed and laboratory‐extracted oils showed that husk seed oils had higher amounts of total tocopherols than naked seed oils. Oils extracted in the laboratory had higher amounts of tocopherols than industrial oils. Pumpkin seed oil, in general, had a high level of squalene, which was higher in husk seed oils than in naked seed oils and in extracted than in pressed oils. The total amount of sterols was higher in husk than in naked seed oils and in extracted oil samples. The main sterols were Δ7‐sterols and their content was similar in all samples, but the content of Δ5‐sterols was higher in oil samples of husk pumpkin seed and in extracted than in pressed oils.     

Fatty Acid, Tocopherol and Sterol Compositions of Canadian Prairie Fruit Seed Lipids

The seeds of four prairie fruits—chokecherry (Prunus virginiana), thorny buffaloberry (Shepherdia argentea), Woods’ rose (Rosa woodsii) and hawthorn (Crataegus × mordenensis)—from Southern Alberta were investigated. The lipid contents of the seeds were found to be 10.4, 11.5, 3.7 and 3.4%, respectively. The tested seed lipids contained mainly linoleic acid in the range from 27.9 to 65.6% and oleic acid from 19.7 to 61.9%. The thorny buffaloberry and Woods’ rose seed lipids contained 29.2 and 30.8% of linolenic acid, respectively. The contents of palmitic and stearic acids ranged from 3.2 to 5.4% and 1.6 to 2.2%, respectively. The contents of total tocopherols in the chokecherry, thorny buffaloberry, Woods’ rose and hawthorn seed lipids accounted for 595, 897, 2,358 and 2,837 mg/kg, respectively. The main sterols in the lipids were β-sitosterol, Δ⁵-avenasterol, cycloartenol, campesterol, stigmasterol and gramisterol. The results of the present study show that the lipids from the seeds of the investigated prairie fruits could be a good source of valuable essential fatty acids, tocopherols and sterols, thus suggesting their application as functional foods and nutraceuticals.     

Lipid Fractions,Fatty Acid Profiles,and Bioactive Compounds of Lithospermum officinale L. Seeds

Seeds of Lithospermum officinale L. from different climatic zones were analyzed for new sources of γ-linolenic acid (GLA, 18:3n-6) and stearidonic acid (SDA, 18:4n-3). Cultured Borago officinalis was also analyzed for comparative purposes. Analyses were conducted for fatty acid (FA) profiles of the glyceride oils from the seeds and in the neutral and polar lipids by gas chromatography (GC); lipid classes by open column chromatography and preparative thin layer chromatography (TLC); and tocopherols, sterols, and phenolic compounds by high-performance liquid chromatography with diode array detection (HPLC-DAD), and the later compounds were confirmed by liquid-chromatography-mass spectrometry (LC–MS). L. officinale from St. Petersburg Botanical Garden showed the highest percentage of GLA (17.9% of total FA), while wild-growing L. officinale from the Rostov region contained the highest percentage of SDA (17.2% of total FA). Total FA content ranged from 11.3 to 20.8% of seed weight. Neutral and polar lipids accounted for ~98 and 2.27%, respectively, of total lipids. Five neutral lipid classes were identified (% of NL): triterpene esters (1.3), triacylglycerols (93.1), free FA (1.8), diacylglycerols (1.4), and monoacylglycerols (2.4). The highest tocopherol content was found in samples from Chechen Republic (35.7 mg/100 g), in which the δ isomer was the main component. Samples from the Rostov region had the highest amounts of sterols (83.8 mg/100 g), and Δ⁵-avenasterol was the predominant compound in all samples. L. officinale seeds contain high amounts of phenolic compounds (389.9 mg/100 g as upper limit), in which rosmarinic acid is highlighted. Overall, all data suggest the possibility of using L. officinale seed oil in pharmaceutical and cosmetic formulae and as functional food.     

Sensory and Physico‐Chemical Properties of Cold Press‐Produced Tomato (Lycopersicon esculentum L.) Seed Oils

In this study, roasted and unroasted (control) tomato seeds were cold pressed and the seeds, oils, and seed presscakes (meals) were analyzed. Some physicochemical properties, total phenolic content and antioxidant capacity, thermal properties, mineral contents, fatty acids, sterols and tocopherols compositions, volatile compounds and sensory evaluation of the tomato seed oils were determined. The tomato seeds contained 3.3 % of ash, 17.3 % of oil and 27.2 % of protein. The cold press oil recovery rate was 7.2 and 10.28 % for control and roasted seeds, respectively. There were eight sensory terms defining the oils together with 34 different aromatic compounds quantified. The volatile compounds furfural, hexanal, benzaldehyde and 2‐isobutylthiazole were found with the highest frequency in the samples. Roasted, green and tomato were defined as characteristic sensory terms for tomato seeds oils. Fifteen different minerals, melting and crystallization temperatures and enthalpies of the oil samples were also quantified. This study provides important data for the tomato seed oils, and proves that pre‐roasted tomato seed oils are high quality, nutritious and aromatics oils with higher levels of consumer acceptability.     

Fatty Acids,Tocopherols and Sterols of <Emphasis Type="Italic">Cephalocroton cordofanus</Emphasis> in Comparison with Sesame,Cotton, and Groundnut Oils

Cephalocroton cordofanus, a perennial much-branched shrub, is dominant in the eastern and western states of Sudan. The seeds of C. cordofanus sesame, groundnut, and cotton were compared for their oil and protein content as well as for fatty acids, tocopherols, and sterols. Fatty acids and sterols were analyzed by GC while tocopherols were analyzed by HPLC. The oil of C. cordofanus showed low levels of saturated fatty acids in comparison with the other three oils. The other reported fatty acids of C. cordofanus were 8.60 % oleic, 17.2% linoleic, 64.2% vernolic, and 2.0% coronaric acids. Neutral lipids, glycolipids, and phospholipids of C. cordofanus oil accounted for 77.5, 14.4, and 8.1% of the total lipid fraction, respectively. The oil of C. cordofanus showed higher levels of tocopherols (113.53 mg/100 g) in comparison to sesame, groundnut, and cottonseed oils, with 64.74, 27.96, and 77.83 mg/100 g, respectively. The primary tocopherol of C. cordofanus was γ-tocopherol (106.21 mg/100 g), which amounted to 93.8% of the total tocopherols. β- and δ-tocopherol were present at levels below 5.0 mg/100 g. In comparison to sesame, groundnut, and cottonseed oils, C. cordofanus oil contains more (304.4 mg/100 g) total sterols than ground nut (294.0 mg/100 g), but less than sesame (774.9 mg/100 g) and cotton seed (492.4) oils. Due to its high level of epoxy fatty acids, C. cordofanus oil is used for industrial rather than edible applications.     

Characterization of Fenugreek (<Emphasis Type="Italic">Trigonella foenum-graecum</Emphasis>) Seed Lipids

The composition and content of lipids, fatty acids, triacylglycerols, tocopherols and sterols in nine fenugreek genotypes were analyzed. Lipid content in fenugreek seeds ranged from 5.8 to 15.2%. Major fatty acids were: linoleic acid (45.1–47.5%), α-linolenic (18.3–22.8%), oleic (12.4–17.0%), palmitic (9.8–11.2%) and stearic (3.8–4.2%) acids. The ratios of n-6 to n-3 fatty acids were between 2.1 and 2.7. Similar fatty acid distribution was observed in all analyzed samples with some deviations. α-Tocopherol was the predominant component found in the fenugreek lipid antioxidants, and it constituted over 84% of the total amounts of tocopherols. It amounts ranged from 620 to 910 mg/kg lipids. β-Sitosterol was the major sterol in all samples, varying from 14,203 to 18,833 mg/kg of lipids. Campesterol and cycloartenol were other major sterols, and these compounds including β-sitosterol constituted 56–72% of all sterols. Fenugreek seed lipids consisted predominantly triunsaturated (56.9–66.5%) and diunsaturated (32.2–41.6%) triacylglycerides. Among these components trilinolein (LLL; 12.9–20.5%) dominated followed by PLL (14.0–20.4%), LnLnO (7.8–17.7%), PLO (5.7–11.6%), OLL (6.9–10.6%), LLLn (3.2–9.6%), and LnLnL (3.5–7.6%). Results of the study show that fenugreek seed lipids may be a source of a nutraceutical ingredient for food applications.     

Variations in the composition of sterols,tocopherols and lignans in seed oils from fourSesamum species

Seeds from different collections of cultivatedSesamum indicum Linn and three related wild species [specifically,S. alatum Thonn.,S. radiatum Schum & Thonn. andS. angustifolium (Oliv.) Engl.] were studied for their oil contents and fatty acid composition of the total lipids. The oils from wild seeds were characterized by higher percentages of unsaponifiables (4.9, 2.6 and 3.7%, respectively) compared toS. indicum (1.4–1.8%), mainly due to their high contents of lignans. Total sterols accounted forca. 40, 22, 20 and 16% of the unsaponifiables of the four species, respectively. The four species were different in the relative percentages of the three sterol fractions (the desmethyl, monomethyl and dimethyl sterols) and in the percentage composition of each fraction. Campesterol, stigmasterol, sitosterol and Δ⁵-avenasterol were the major desmethyl sterols, whereas obtusifoliol, gramisterol, cycloeucalenol and citrostandienol were the major monomethyl sterols, and α-amyrin, β-amyrin, cycloartenol and 24-methylene cycloartanol were the main dimethyl sterols in all species. Differences were also observed among the four species in sterol patterns of the free sterols compared to the sterol esters.Sesamum alatum contained less tocopherols (210–320 mg/kg oil), andS. radiatum andS. angustifolium contained more tocopherols (ca. 750 and 800 mg/kg oil, respectively) than didS. indicum (490–680 mg/kg oil). The four species were comparable in tocopherol composition, with γ-tocopherol representing 96–99% of the total tocopherols. The four species varied widely in the identity and levels of the different lignans. The percentages of these lignans in the oils ofS. indicum were sesamin (0.55%) and sesamolin (0.50%).Sesamum alatum showed 1.37% of 2-episesalatin and minor amounts of sesamin and sesamolin (0.01% each).Sesamum radiatum was rich in sesamin (2.40%) and contained minor amounts of sesamolin (0.02%), whereS. angustifolium was rich in sesangolin (3.15%) and also contained considerable amounts of sesamin (0.32%) and sesamolin (0.16%).     

Effects of Seed Roasting on Tocopherols,Carotenoids, and Oxidation in Mustard Seed Oil During Heating

Seed roasting is practiced in the mustard oil industry in some areas of the world, and can affect the physicochemical properties of the oil for further applications. This research studied the differences in oxidative stability, tocopherols, and carotenoids during heating at 160 °C between oil extracted from roasted mustard seeds and that from unroasted seeds. The content of free fatty acids, polar compounds (PC), and lutein were not significantly different between the roasted and unroasted seed oils before heating. The fatty acid compositions of both oils were also similar, with high amounts of erucic, linoleic, and oleic acids, moderate amounts of linolenic and eicosenoic acids, and low amounts of palmitic and stearic acids. However, the levels of tocopherols and conjugated dienoic acids (CDA) were higher in the roasted seed oil. Heating increased the content of CDA and PC in both oils, but decreased tocopherols and lutein. The rates of increase in CDA and PC and the degradation rates of tocopherols and lutein during heating were lower in the roasted than in the unroasted seed oil. Overall, the increased thermo-oxidative stability of the mustard oil by roasting the seeds before oil extraction was highly correlated with improved heat stabilities for both tocopherols and lutein.     

Chemical evaluation of some paprika (Capsicum annuum L.) seed oils

The oil contents of seeds from paprika (Capsicum annuum L.) collected from different locations in Turkey and Italy varied in a relatively wide range from 8.5 g/100 g to 32.6 g/100 g. The fatty acid, tocopherol and sterol contents of the oils from different paprika seeds were investigated. The main fatty acids in paprika seed oils were linoleic acid (69.5–74.7 g/100 g), oleic acid (8.9–12.5 g/100 g) and palmitic acid (10.7–14.2 g/100 g). The oils contained an appreciable amount of γ‐tocopherol (306.6–602.6 mg/kg), followed by α‐tocopherol (7.3–148.7 mg/kg). The major sterols were β‐sitosterol (1571.4–4061.7 mg/kg), campesterol (490.8–1182.7 mg/kg), and Δ⁵‐avenasterol (374.5–899.6 mg/kg). The total concentration of sterols ranged from 3134.0 mg/kg to 7233.7 mg/kg. Remarkable amounts of cholesterol were found in the different samples (164.6–491.0 mg/kg). The present study showed that paprika seeds are a potential source of valuable oil that could be used for edible and industrial applications.     

Lipid Profiles of Tunisian Coriander (<Emphasis Type="Italic">Coriandrum sativum</Emphasis>) Seed

Coriander (Coriandrum sativum L.) seeds were harvested from the region of Korba (North-East Tunisia) in order to characterize their fatty acids, phytosterols, tocopherols and tocotrienols (tocols) profiles. Nine fatty acids, with petroselinic acid accounting for 76.6% of the total fatty acids, followed by linoleic, oleic and palmitic acids, accounting for 13.0, 5.4 and 3.4%, respectively, of the total fatty acids were identified. Neutral lipids (NLs) were mainly composed of triacylglycerols (98.4%). Polar lipids were mainly composed of phosphatidylcholine as the major phospholipid (PL) subclass, whereas digalactosyldiacylglycerol was the major galactolipid (GL). Total sterols content was estimated to be 36.93 mg/g oil. Stigmasterol accounted for 29.5% of the total sterols. Other representative sterols were β-sitosterol, Δ⁷-stigmasterol and Δ⁵, 24-stigmastadienol, which accounted for 24.8, 16.3 and 9.2%, respectively. Gamma-tocotrienol was the predominant tocol at 238.40 μg/g seed oil. This was equivalent to 72.8% of the total tocols followed by γ-tocopherol (8.06%) and α-tocopherol (7.6%).     

Comparison of Supercritical Fluid and Hexane Extraction Methods in Extracting Kenaf (<Emphasis Type="Italic">Hibiscus cannabinus</Emphasis>) Seed Oil Lipids

The objective of this study was to investigate and compare fatty acids, tocopherols and sterols of kenaf seed oil extracted by supercritical carbon dioxide and traditional solvent methods. Fatty acids, tocopherols and sterols were determined in the extracted oils as functions of the pressure (400 bar, 600 bar), temperature (40 °C, 80 °C) and CO₂ flow rate (25 g/min) using a 1-L extraction vessel. Gas chromatography was used to characterize fatty acids and sterols of the obtained oils while tocopherols were quantified by HPLC. No differences were found in the fatty acid compositions of the various oil extracts and the main components were found to be linoleic (38%), oleic (35%), palmitic (20%) and stearic acid (3%). Extraction of tocopherols using high pressure (600 bar/40 °C, 600 bar/80 °C) gave higher total tocopherols (88.20 and 85.57 mg/100 g oil, respectively) when compared with hexane extraction which gave yield of 62.38 mg/100 g oil. Extraction of kenaf seed oil using supercritical fluid extraction at high temperature (80 °C) gave higher amounts of sterols when compared with hexane extraction.     

Dragon Fruit (Hylocereus spp.) Seed Oils: Their Characterization and Stability Under Storage Conditions

Oil was extracted from the seeds of white-flesh and red-flesh dragon fruits (Hylocereus spp.) using a cold extraction process with petroleum ether. The seeds contained significant amounts of oil (32–34 %). The main fatty acids were linoleic acid (C18:2, 45–55 %), oleic acid (C18:1, 19–24 %), palmitic acid (C16:0, 15–18 %) and stearic acid (C18:0, 7–8 %). The seed oils are interesting from a nutritional point of view as they contain a large amount of essential fatty acids, amounting to up to 56 %. In both dragon fruit seed oils, tri-unsaturated triacylglycerol (TAG) was mainly found while their TAG composition and relative percentage however varied considerably. Therefore, they showed a different melting profile. A significant amount of total tocopherols was observed (407–657 mg/kg) in which the α-tocopherol was the most abundant (~72 % of total tocopherol content). The impact of storage conditions, cold and room temperatures, on the oxidative stability and behavior of tocopherols was monitored over a 3-month storage period. During storage, the oxidative profile changed with a favorably low oxidation rate (~1 mequiv O₂/week) whilst tocopherols decreased the most at room temperature. After 12 weeks, the total tocopherol content, however, still remained high (65–84 % compared to the initial oils). Hereto, the dragon fruit seed oils can be considered as a potential source of essential fatty acids and tocopherols, with a good oxidative resistance.     

Acetate and mevalonate labeling studies with developingCuphea lutea seeds

Cuphea seeds contain large amounts of medium chain (C₈ to C₁₄) fatty acids, mainly as triacylglycerols. The biosynthesis of these lipids was studied in vivo by incubating developingCuphea lutea seeds with labeled acetate. Incorporation of label into triacylglycerols and into medium chain fatty acids occurred principally during the period of endogenous lipid deposition, but some label was encountered in these products even during seed dehydration. At this later stage palmitate and oleate were the dominant labeled fatty acids. During the period of rapid endogenous lipid deposition acyl lipids other than triacylglycerols were minor labeled components. The labeling patterns were consistent with the Kennedy pathway for triacylglycerol biosynthesis. The fatty acid composition of the acyl-CoA pool was similar to the total lipid fatty acid composition, but the acyl-ACP pool contained relatively more short chain acyl groups. Squalene was labeled from acetate throughout the period of seed development, but labeled sterols were not detected. Using [2-¹⁴C]mevalonic acid lactone as substrate, squalene was the principal labeled product. Small amounts of label were found in free sterols. However, in terms of mass, free sterol dominated over squalene. The possibility of two independent sites of isoprenoid biosynthesis in the developing embryo is discussed.     

Investigation of lipids profiles of Nigella, lupin and artichoke seed oils to be used as healthy oils

Nigella sativa, lupin and artichoke seed oils have been investigated. The oils were subjected to detailed studies using gas chromatographic analysis (GLC) for fatty acids (FA, as methyl esters) and whole sterols (as silyl derivatives). Whereas, high pressure liquid chromatography (HPLC) was employed for determination of molecular species of triacylglycerols (TAG), four sterol lipids (free and acylated sterols, FS and AS, and free and acylated sterylglycosides, FSG and ASG, as their anthroylnitrile derivatives) as well as tocopherol patterns (T). The results showed that the three seed oils are rich in oleic and linoleic acids whereas, lupin had high linolenic acid content. It was found that the TAGs of the three oils showed some similarity with sunflower oil. Lupin oil had higher sterol content and it was very rich in campe- and β-sitosterol. Nigella sativa oil had a high content of isofucosterol, whereas artichoke oil was unique in having a high content of 5-stigma-, 7-stigma-, and avena- sterol. Concerning the FS and AS, Nigella sativa oil had the highest content, whereas artichoke oil had the highest content of FSG and ASG. Nigella sativa and lupin oils contained over 90 % γ-T while, artichoke oil comprised about 100 % α-T. It is recommended to use the three oils as healthy oils and folk medicine.     

Chemical composition of Pinus sibirica nut oils

The chemical composition of oil obtained from Pinus sibirica was investigated. The nonpolar lipids were the predominant lipid fraction while the triacylglycerols were the major component of this fraction. α‐ and γ‐tocopherols were the dominant tocopherols in pine oils. Eleven fatty acids (FA) were identified in pine nut oil. The unsaturated FA comprised over 90% of the total FA. Of these, polyunsaturated FA accounted for 66% of the total FA. 18:2 and 18:3 acids were the dominant unsaturated FA, while palmitic and stearic acids were the major saturated FA. Three unusual FA, namely 10,13‐octadecadienoic, gorlic and 11,13‐eicosadienoic acid, were tentatively identified in pine nut oil.     

Microwave-Assisted,Base-Catalyzed Synthesis of Fatty Acid Methyl Esters from Seeds and Fish Oil Supplements

Growing health awareness has resulted in the increased use of dietary supplements derived from plants and marine sources, leaving consumers unsure of their best options. There were three objectives of the present study. The first was to design and evaluate an efficient derivatization procedure. The second was to perform a comparative analysis of liquid oils and their corresponding capsules of hemp, chia, and flax seeds. The final objective was to determine the fatty acid (FA) composition of six fish oil products and compare it to the one provided on the label. For the FA profiling, we implemented two efficient, one-step, sustainable methods with high percentage recovery for the synthesis of FA methyl esters (FAME), which use base catalysis and microwave-assisted heating. Our results found no difference in nutritional value between liquid oils and capsules of the seed supplements, with flaxseed and chia offering a higher, beneficial n-3:n-6 ratio compared to hemp oil. Four of the fish oils analyzed contained significantly less eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) than their reported label, and the other two not only agreed with the manufacturers' declaration but were able to fulfill the daily adequate intake (AI) with fewer capsules.     

Contents of Carotenoids, Tocopherols and Sterols in Acacia cyanophylla Seed Oils

Seeds from 12 Acacia cyanophylla ecotypes, harvested in Tunisia, were examined for their seed oil contents of carotenoids, tocopherols and phytosterols. The average carotenoid content (lutein and zeaxanthin) was ca. 102 mg kg^?1 of total extracted lipids. Lutein (ca. 97 mg kg^?1 of total extracted lipids) was usually more abundant than zeaxanthin (ca. 5 mg kg^?1 of total extracted lipids). The mean total tocopherol content was ca. 704 mg kg^?1 of total extracted lipids. The main isomer was α‐tocopherol, with more than 75 % of total tocopherols (ca. 528 mg kg^?1 of total extracted lipids), followed by γ‐tocopherol (ca. 168 mg kg^?1 of total extracted lipids) and δ‐tocopherol (ca. 86 mg kg^?1 of total lipids). High levels of phytosterols (ca. 7.8 g kg^?1 of total extracted lipids) were detected, among which β‐sitosterol was the most abundant (47 %). All these results highlight the richness of carotenoids, tocopherols and sterols in A. cyanophylla seed oil, and imply that this species might constitute a potential resource for the development of functional foods.     

Variations in the composition of acyl lipids and triacylglycerol molecular species of pumpkin seeds (Cucurbita spp.) following microwave treatment

Whole pumpkin seeds (Cucurbita spp.) of two cultivars were exposed to microwaves for 6, 12, 20 or 30 min at a frequency of 2450 MHz. The kernels were separated from the whole seeds, and were investigated not only for the different acyl lipids and their fatty acid compositions, but also for the molecular species of triacylglycerols (TAGs). A modified argentation TLC procedure, developed to optimize the separation of the complex mixture of total TAGs, provided 11 different groups of TAGs, based on both the degree of unsaturation and the chain‐length of fatty acid groups. With a few exceptions, dioleopalmitin (5.8–18.8 wt‐%), dipalmitolinolein (8.1–8.8 wt‐%), triolein (6.3–20.5 wt‐%), palmitoleolinolein (15.0–16.1 wt‐%), dioleolinolein (16.7–23.0 wt‐%), dilinoleopalmitin (4.6–15.4 wt‐%) and dilinoleolein (6.7–19.4 wt‐%) were the main TAG components. When pumpkin seeds were microwaved for 20 min or more, significant differences (p <0.05) occurred in the acyl lipids as well as their fatty acid distributions with a few exceptions. Therefore, microwave roasting caused a significant decrease (p <0.05), not only in TAGs molecular species containing more than 4 double bonds, but also in the amounts of diene species present in triacylglycerols. These results contribute to the study of the functional properties of pumpkin seed products.     

Chemical Composition of Seed Oils Recovered from Different Pear (Pyrus communis L.) Cultivars

Lipophilic bioactive compounds in oils recovered from the seeds of eight pear (Pyrus communis L.) cultivars were studied. Oil yield in pear seeds ranged between 16.3 and 31.5 % (w/w) dw. The main fatty acids were palmitic acid (6.13–8.52 %), oleic acid (27.39–38.17 %) and linoleic acid (50.73–63.78 %), all three representing 96–99 % of the total detected fatty acids. The range of total tocochromanols was between 120.5 and 216.1 mg/100 g of oil. Independent of the cultivar, the γ‐tocopherol was the main tocochromanol and constituted approximately 88 %. The contents of the carotenoids and squalene were between 0.69–2.99 and 25.5–40.8 mg/100 g of oil, respectively. The β‐sitosterol constituted 83.4–87.6 % of total sterols contents, which ranged between 276.4 and 600.1 mg/100 g of oil. Three significant correlations were found between oil yield and total contents of sterols (r = ?0.893), tocochromanols (r = ?0.955) and carotenoids (r = ?0.685) in pear seed oils.     

Lipid composition of millet (Pennisetum americanum) seeds

The composition of lipids extracted from a sample of millet seeds by each of 8 solvent systems is reported. Lipid components were separated by silicic acid column and thin layer chromatography (TLC) and quantitated by analysis of fatty acid methyl esters by gas liquid chromatography (GLC), with heptadecanoic acid as internal standard. Best results were obtained by extraction with hot water-saturated butanol. Lipids extracted amounted to 7.2% of the seed dry weight and consisted of 85% neutral lipids, 12% phospholipids and 3% glycolipids. Neutral lipids contained mostly (85%) triacylglycerols and small amounts of mono- and diacylglycerols, sterols and free fatty acids. Sterols consisted of campesterol, stigmasterol and 2 unidentified sterols, occurring in the same proportions in free and esterified forms. Ten glycolipid and 10 phospholipid components were separated and characterized. Contrary to previously published observations, lysophosphatidylcholine was the major phospholipid (42%) in millet seeds; smaller amounts of phosphatidylcholine (24%), lysophosphatidylethanolamine (21%) and trace amounts of phosphatidylglycerol, phosphatidic acid, phosphatidylserine and phosphatidylinositol also were present. The major glycolipids were esterified sterol glycoside, sterol glycoside, monogalactosyldiacylglycerol, digalactosyldiacylglycerol and cerebrosides (ceramide monohexosides).