Chemical and nutritional evaluation ofPongamia glabra oil andAcacia auriculaeformis oil

Karanja seed(Pongamia glabra) oil contains toxic flavonoids including 1.25% karanjin and 0.85% pongamol. After refining the oil resembles peanut oil in composition and is free from toxic flavonoids, bitterness and unpleasant odors. Akashmoni seed(Acacia auriculaeformis) oil is rich in stearic acid (31%), and nearly two-thirds of its glyceride is GS₂ U (disaturated monounsaturated), mostly SOS (saturated-stearic acid and unsaturated-oleic acid). Nutritional evaluations of these two refined seed oils were carried out in rats by feeding the respective oils and peanut oil as control at 10% level in a 20% protein diet for 12 weeks. The animals fed karanja oil showed poor growth performance, altered lipid metabolism and fatty infiltration in liver. Akashmoni oil in the diet of rats did not reveal growth retardation or any abnormalities in evaluations of lipid parameters of serum and liver or histopathological findings. The results of this study indicate that refined karanja oil is toxic to rats and may not be desirable for edible purposes, while akashmoni oil may be desirable.     

Chemical and nutritional studies on the seed oil ofAcacia arabica

The seeds ofAcacia arabica contain 5.2% oil. Physicochemical constants and fatty acid composition of the refined seed oil were determined. The seed oil was rich in linoleic acid (39.2%) and oleic acid (32.8%). Trace quantities of epoxy and hydroxy fatty acids were present in the seed oil. Nutritional evaluation of the refined seed oil was done by rat bioassay with peanut oil as control. The animals fed 10% seed oil showed poor growth performance and low feed efficiency ratio. The digestibility of the seed oil was 90% compared to 94% for peanut oil. The seed oil in the diet of rats for 4 wk did not produce any abnormal serum lipids or histopathological findings.     

Effects of Pinus pinaster and Pinus koraiensis seed oil supplementation on lipoprotein metabolism in the rat

The aim of the present study was to assess the effect of vegetal oils obtained from Pinus pinaster and P. koraiensis seeds on plasma lipoprotein levels and apolipoprotein (apo) gene expression in rats. These oils contain two particular fatty acids of the Δ5-unsaturated polymethylene-interrupted fatty acid (Δ5-UPIFA) family: all-cis-5,9,12-18:3 (pinolenic) and/or all-cis-5,11,14-20:3 (sciadonic) acids. Rats were fed for 28 d a diet containing 5% (w/w) oil supplement. Two control diets were prepared to match the fatty acid composition of P. pinaster or P. koraiensis oils with the exception of Δ5-UPIFA, which were replaced by oleic acid. Pinus pinaster seed oil decreased serum triglycerides by 30% (P<0.02), very low density lipoprotein (VLDL)-triglycerides by 40% (P<0.01), and VLDL-cholesterol by 33% (P<0.03). Pinus koraiensis seed oil decreased serum triglycerides by 16% [not statistically significant (ns)] and VLDL-triglycerides by 21% (ns). Gel permeation chromatography and nondenaturating polyacrylamide gel electrophoresis showed a tendency of high density lipoprotein to shift toward larger particles in pine seed oil-supplemented rats. Finally, P. pinaster seed oil treatment was associated with a small decrease of liver apoC-III (P<0.02) but not in apoE, apoA-I, or apoA-II mRNA levels. The levels of circulating apo were not affected by pine seed oil supplementation. In conclusion, P. pinaster seed oil has a triglyceride-lowering effect in rats, an effect that is due to a reduction in circulating VLDL.     

Investigation of the technological properties ofNigella sativa (black cumin) seed oil

Three commercially cultivatedNigella sativa seed varieties of Turkish origin were analyzed, and the characteristics and constituents of the seed oils were reported. Presence of lipase enzyme in seed results in enzymatic hydrolysis at ordinary temperature; the free acid content of oil may increase up to 40% or higher. Black cumin seed oil might serve as a source of semi-drying oil and fatty acids of technical grade, and the removal of free fatty acids from oil and the recovery of fatty acids were investigated.     

Fatty acid composition of melon seed oil lipids and phospholipids

Fatty acid compositions of crude melon seed oil from two different sources were compared. Melon seeds fromCitrullus vulgaris (syn.C. lanatus) contained phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and phosphatidylserine (PS), whereas melon seeds fromCitrullus colocynthis contained only PC and LPC, but not PS. Analysis of the total lipids revealed that the major fatty acid of the oils was 18:2n-6.Citrullus vulgaris seed oil contained 71.3% andC. colocynthis contained 63.4% of 18:2n-6. The predominant fatty acids in theC. vulgaris PC were 18:2n-6 (32.2%), 18:1n-9 (26.4%) and 16:0 (22.2%), whereas theC. colocynthis PC contained 44.6% of 18:1n-9 as the major fatty acid. The level of monoenes in theC. colocynthis variety (46.2%) was different from theC. vulgaris (27.3%). The major fatty acid in the LPC was 18:1n-9 for both varieties. Notably, theC. colocynthis variety did not contain any PS. The major fatty acids in theC. vulgaris PS were 18:1n-9 (37.9%) and 18:2n-6 (33.7%). Of all the phospholipids, LPC contained the greatest amount of monoenes, 48.6–52.4%.     

Metabolism of erucic acid in perfused rat liver: Increased chain shortening after feeding partially hydrogenated marine oil and rapeseed oil

The metabolism of [14-¹⁴C] erucic acid was studied in perfused livers from rats fed on diets containing partially hydrogenated marine oil or rapeseed oil for three days or three weeks. Control rats were given groundnut oil. Chain-shortening of erucic acid, mainly to 18∶1, was found in all dietary groups. In the marine oil and rapeseed oil groups, the percentage of chain-shortened fatty acids in very low density lipoproteins-triacylglycerols (VLDL-TG) exported from the liver increased after prolonged feeding. A similar increase was found in liver TG only with partially hydrogenated marine oil. This oil, rich intrans fatty acids, thus seemed to be more effective in promoting chain-shortening. The fatty acid composition of the secreted and stored TG differed both with respect to total fatty acids and radioactively labeled fatty acids, indicating that at least 2 different pools of TG exist in the liver. The lack of lipidosis in livers from rats fed dietary oils rich in 22∶1 fatty acids is discussed in relation to these findings. In conclusion, a discussion is presented expressing the view that the reversal of the acute lipidosis in the hearts of rats fed rapeseed oil or partially hydrogenated marine oils is, to a large extent, derived from the increased chain-shortening capacity of erucic acid in liver.     

Nutritional evaluation of refined,heated and hydrogenatedHibiscus sabdariffa seed oil

Alkali refinedHibiscus sabdariffa seed oil (Mesta Oil) of the familyMalvales was heated and hydrogenated to eliminate the cyclopropene fatty acids (CPFA). Such processed oils were fed to weanling rats at 10% level of the diet for 4, 8 and 12 weeks. The food intake and gain in weight were found to be less in the refined oil group than in the peanut oil control group. The digestibility was found normal with all the processed oils. Serum and liver lipid composition with respect to total lipids, cholesterol and phospholipids were comparable to those fed with peanut oil. The liver architecture did not show any abnormalities withH. sabdariffa oil feeding.     

Composition and physicochemical properties of Combretum collinum,Combretum micranthum,Combretum nigricans,and Combretum niorense seeds and seed oils from Burkina Faso

Combretum collinum, Combretum micranthum, Combretum nigricans, and Combretum niorense are abundant unconventional seed oils of the African savannah. In this study, the proximate, mineral, amino acid, fatty acid, and triacylglycerol compositions of the four seed oils were quantified, and the oxidative and physicochemical properties were investigated. The amino acid, fatty acid, and triacylglycerol compositions were determined by using high performance liquid chromatography (HPLC) and gas chromatography respectively. Carbohydrates (57.35%–64.20%) followed by crude oils (20.07%–22.60%), proteins (11.95%–15.86%), and ashes (3.78%–6.19%) were the main constituents of the four seed species. The highest ash, crude fat, and protein contents were found in C. collinum, C. nigricans, and C. niorense, respectively. All four seed species were rich in Ca, K and Mg, and poor in methionine, cysteine, and lysine. The four seed oils had high saponification values (198.46–202.71 mgKOH/g), low acidity (1.12–2.26 mg of KOH/g of oil), and peroxide values (1.19–1.98 mEqO₂/kg of oil). The seed oils of C. micranthum and C. collinum exhibited the highest thermal oxidative stability (8.10 and 9.79 h at 160°C). Oleic (40.49%–56.69%), palmitic (15.17%–24.27%) and linoleic (9.49%–14.50%) acids were the predominant fatty acids of the four seed oils. The results showed that the four seed species and seed oils had good chemical composition and physicochemical properties making them suitable for food and non-food application.     

Vegetable oil raw materials

Vegetable oils that are important to the chemical industry include both edible and industrial oils, which contribute 24% and 13.5%, respectively, compared to 55% for tallow, to the preparation of surfactants, coatings, plasticizers, and other products based on fats and oils. Not only the oils themselves but also the fatty acids recovered from soapstock represent a several billion pound resource. Coconut oil is imported to the extent of 700-1,000 million pounds per year. Its uses are divided about equally between edible and industrial applications. Safflower oil has a relatively small production, but 15–25% of the oil goes into industrial products. Soybean oil, the major edible oil of the world, is produced in the United States at the rate of 11,000 million pounds per year with more than 500 million pounds going into industrial uses, representing 5% of the total production. Castor oil is imported to the extent of about 100 million pounds per year. Linseed oil production has declined drastically over the last 25 years but still amounts to about 100 million pounds per year. Oiticica and tung oils are imported in lesser amounts than castor and linseed oils. New crops that have industrial potential, as well as the traditional vegetable oil crops, include seed oils from crambe,Limnanthes, Lesquerella, Dimorphotheca, Vernonia, andCuphea plants. Crambe oil contains up to 65% erucic acid. Oil fromLimnanthes contains more than 95% of fatty acids above C₁₈.Lesquerella oil contains hydroxy unsaturated acids resembling ricinoleic acid from castor oil.Dimorphotheca oil contains a conjugated dienol system.Vernonia oils contain as much as 80% epoxy acids. TheCuphea oils contain a number of short chain fatty acids. Of these, crambe,Limnanthes, andVernonia are probably the most developed agronomically. Competition between vegetable oils and petrochemicals for the traditional fats and oil markets has been marked over the past 25 years, but prices for petrochemicals have accelerated at a greater rate than those for vegetable oils; and, it is now appropriate to reexamine the old as well as the new markets for fatty acids.     

Deacidification of black cumin seed oil by selective supercritical carbon dioxide extraction

The deacidification of high-acidity oils from Black cumin seeds (Nigella sativa) was investigated with supercritical carbon dioxide at two temperatures (40 and 60°C), pressures (15 and 20 MPa) and polarities (pure CO₂ and CO₂/10% MeOH). For pure CO₂ at a relatively low pressure (15 MPa) and relatively high temperature (60°C), the deacidification of a highacidity (37.7 wt% free fatty acid) oil to a low-acidity (7.8 wt% free fatty acid) oil was achieved. The free fatty acids were quantitatively (90 wt%) extracted from the oil and left the majority (77 wt%) of the valuable neutral oils in the seed to be recovered at a later stage by using a higher extraction pressure. By reducing the extraction temperature to 40°C, increasing the extraction pressure to 20 MPa, or increasing the polarity of the supercritical fluid via the addition of a methanol modifier, the selectivity of the extraction was significantly reduced; the amount of neutral oil that co-extracted with the free fatty acids was increased from 23 to 94 wt%.     

The decomposition of secondary esters of castor oil with fatty acids

In this study, thermal splitting of secondary fatty acid esters of castor oil was investigated to determine the reaction kinetics under various conditions. Zinc oxide,p toluenesulfonic acid and sulfuric acid were used as catalysts. Reactions were carried out at 260, 270, and 280°C. Experimental data fitted the first-order rate equation for the catalyzed and noncatalyzed reactions. In addition to the kinetic investigation, the splitting (pyrolysis) mixture was evaluated in the preparation of a synthetic drying oil. For this purpose, the mixed fatty acids of linseed, sunflower andEcballium elaterium seed oils were used in the esterification stage of the process. Pyrolysis mixtures were converted to drying oils by combining the liberated acids with equivalent amounts of glycerol. The oils thus obtained show good drying oil properties.     

γ-Linolenic acid concentrates from borage and evening primrose oil fatty acidsvia lipase-catalyzed esterification

γ-Linolenic acid (GLA, all-cis 6,9,12-octadecatrienoic acid) has been enriched from fatty acids of borage (Borago officinalis L.) seed oil to 93% from the initial concentration of 20% by lipase-catalyzed selective esterification of the fatty acids withn-butanol in the presence ofn-hexane as solvent. The immobilized fungal lipase preparation, Lipozyme, used as biocatalyst, preferentially esterified palmitic, stearic, oleic and linoleic acids and discriminated against GLA, which was thus concentrated in the unesterified fatty acids fraction. In the absence of hexane, concentrate containing about 70% GLA was obtained. When the reaction conditions, optimized for borage oil fatty acids, were applied to fatty acids of evening primrose (Oenothera biennis L.) oil, concentrates containing 75% GLA were obtained. From both oils, GLA concentrates were prepared efficiently in short reaction times (1–3 h) at 30–60°C. The process can be applied for the production of GLA concentrates for dietetic purposes.     

Dihydrosterculic acid,a major fatty acid component ofEuphoria longana seed oil

The seed oil ofEuphoria longana, Sapindaceae, contains 17.4% of 9,10-methyleneoctadecanoic (dihydrosterculic) acid. This identification is based on information from thin layer chromatography, infrared analysis, gas liquid chromatography, nuclear magnetic resonance and mass spectroscopy. Since GLC of the oil showed components that emerged between the usual triglycerides, the cyclopropanoid acid is apparently a triglyceride constituent. The presence of smaller amounts, less than 1%, of cyclopropanoid fatty acids of different chain lengths is indicated by GLC and TLC analyses of the methyl esters. The other major fatty acids in this oil are: 16∶0 (19%), 18∶0 (7%), 18∶1 (36%), 18∶2 (6%), 18∶3 (5%) and 20∶0 (4%).Euphoria oil contains considerably larger amounts of cyclopropanoid fatty acids than previously reported in other seed oils. Presented at the AOCS-AACC Joint Meeting, Washington, D.C., April 1968. No. Utiliz. Res. Dev. Div.; ARS, USDA.     

Peanut oil: Compositional data

The major fatty acids of peanut oil acylglycerols are palmitic (C16:0), oleic (C18:1), and linoleic (C18:2) acids, and only a trace amount of linolenic fatty acid (C18:3) is present. Thus they have a very convenient oxidative stability and have been considered premium cooking and frying oils. This paper provides information about compositional data of peanut oil taking into account major (triacylglycerols and their fatty acids) and minor (free fatty acids, diacylglycerols, phospholipids, sterols, tocopherols, tocotrienols, triterpenic and aliphatic alcohols, waxes, pigments, phenolic compounds, volatiles, and metals) compounds. Moreover, the influence of genotype, seed maturity, climatic conditions, and growth location on peanut oil chemical composition is considered in the present report. In addition, peanut oils from wild species found in South America as well as from peanut lines developed through conventional breeding are also compared.     

Nutritional and toxicological evaluation of rubber seed oil

Rubber (Hevea brasiliensis) seed oil (RSO) is available in India (Ca. 4500 tons per year) and is used mainly as a drying oil. The oil does not contain any unusual fatty acids, and it is a rich source of essential fatty acids C_18∶2 and C_18∶3 that make up 52% of its total fatty acid composition. Acute toxic potential in rats and the systemic effects and nutritional quality were assessed in a 13 week feeding study in weanling albino rats using a diet containing RSO or groundnut oil (GNO) (as the control) at a 10% level as the sole source of dietary fat. RSO did not manifest any acute toxic potential. Food consumption, growth rate and feed efficiency ratio of rats fed RSO were similar to those fed GNO. The digestibility of this oil was found to be 97%, as compared to 94% for GNO. There were no macroscopic or microscopic lesions in any of the organs which could be ascribed to the RSO incroporation in the diet. Thus the current data show that RSO could be used for edible purposes. However, it will be necessary to process the oil to achieve deodorization and to remove free fatty acids to make it organoleptically acceptable.     

Cis-5-monoenoic fatty acids ofCarlina (Compositae) seed oils

Seed oils ofCarlina corymbosa L. andC. acaulis L. containcis-5-octadecenoic acid as a major fatty acid (21–24%). This acid has not been previously reported as a constituent of Compositate seed oils. The predominant fatty acid in theCarlina oils is linoleic (50–52%); lesser amounts (≦10% each) of palmitic, stearic and oleic acids are also present. The oil ofC. acaulis has almost 2% ofcis-5-hexadecenoic acid;C. corymbosa oil includes minor amounts of some oxygenated fatty acids. Presented at the AOCS Meeting, New York, October 1968. No. Utiliz. Res. Dev. Div., ARS, USDA.     

Acetylenic acids ofAlvaradoa amorphoides seed oil

Oil from the seed ofAlvaradoa amorphoides Liebm. (Simaroubaceae) collected in Mexico contains two acetylenic fatty acids previously unknown in seed oils, 15% of 17-octadecen-6-ynoic and a trace amount of 6-eicosynoic acid. The predominant fatty acid (58%) in the oil is 6-octadecynoic (tariric). Both the δ6 and δ9 series of hexadecenoic, octadecenoic, octadecadienoic, and octadecatrienoic acids were found, but only the δ6 isomer of eicosenoic acid (1.4%) was detectec. The mono- and dienoic acids make up about 19% of the total oil. The remainder consists mostly of saturated acids (6.3%). Techniques used in isolation and identification of the acids included thin layer and gas chromatography, IR, UV, NMR and mass spectroscopy, and ozonolysis coupled with gas chromatography. Presented at the 7th Great Lakes Regional American Chemical Society Meeting, Kalamazoo, Mich., June, 1973. ARS, USDA     

Stability of pumpkin seed oil

In Austria pumpkins are grown primarily for the production of pumpkin seeds that can be used for eating or the production of salad oil. Pumpkin seed oil is dark green and its fatty acid composition consists typically of linoleic acid and oleic acid as the dominant fatty acids. The saturated fatty acids palmitic and stearic acid occur at lower levels. The samples for this study were taken from a breeding program that intends to increase the seed and oil productivity. 15 samples with different contents of linoleic acid (40—57%) and vitamin E (100—600 μg/g) were selected. The stability of the oil was measured in a Rancimat that oxidizes the oil at 120 �C and measures the induction time that is needed for the oxidation. The correlation analysis showed that only the ratio of linoleic acid to oleic acid had a significant influence on the oxidative stability of the oil. Vitamin E did not show any correlation. When α‐tocopherol was added to the oil a strong pro‐oxidative effect was observed.     

Aqueous enzymatic extraction and quality evaluation of Acer truncatum Bunge seed oil

Aqueous enzymatic extraction (AEE) of oil from Acer truncatum Bunge seed kernel was investigated. The effects of enzyme type on the extraction yield of oil were studied, and the results showed that the oil yield obtained with pentosanase was higher than that obtained with the other enzymes. The combination of pentosanase and cellulase showed better extraction performance than a single enzyme, and the operation parameters of the AEE method were optimized. A maximum oil yield of 37.94% was obtained. The analysis results of chemical compositions of the extracted oils showed that the content of unsaturated fatty acids in the oil extracted by the AEE method was 90.28%, and the content of nervonic acid was about 5.59%. In addition, the main physical and chemical properties of A. truncatum Bunge seed oil were measured. The oil obtained by the AEE method met the China National Standard of A. truncatum Bunge oil.     

Studies of Oils of Unusual Fatty Acids

Studies of linseed, castor seed and Vernonia anthelmintica seed oils have been undertaken together keeping in view their industrial importance. Linseed oil contains the highest percentage of linolenic acid (69.1%) whereas the highest percentage of hydroxy fatty acid (85.6%) and epoxy fatty acids (76.8%) has been found out in castor seed and Vernonia anthelmintica seed oils respectively as determined by the application of thin-layer and gas liquid chromatography.