Oil Erucic Acid Research Articles

Evaluating the effects of very long chain and hydroxy fatty acid content on tribological performance and thermal oxidation behavior of plant-based lubricants

Here, we assess several potential plant-based lubricants to reveal their functional characteristics in comparison to the traditionally used synthetic lubricant polyalphaolefin 4 and 10 oils. Our results indicate that jojoba and castor oils demonstrate the best oxidation resistance at elevated temperatures. The low erucic acid (LE) oils demonstrated a decrease in the lubrication efficiency already at 150 °C. This performance was inferior to that of canola oil which also has low erucic acid content, possibly due to the LE pennycress oil having relatively higher polyunsaturated fatty acid content. These results provide a comprehensive overview of plant-based oil candidates, including some with very long chain fatty acids and/or hydroxylated fatty acids, and suggest new concepts for lubrication efficiency improvement.

Solvent extraction and characterization of Brassica carinata oils as promising alternative feedstock for bio-jet fuel production.

As a fossil fuel substitute, bio-jet fuel derived from inedible oilseed crops has the potential to improve energy security, decrease carbon footprint, and promote agricultural economy and social development. The efficient production of bio-jet fuels depends on the identification and characterization of eco-friendly and sustainable feedstocks. Brassica carinata (Arun Braun) cultivars are among the most significant industrial oilseeds that can be utilized as alternative feedstocks in the aviation industry. The study thoroughly evaluated four non-food Brassica carinata cultivars that are indigenous to Ethiopia to determine their suitability as substitute feedstocks for the production of bio-jet fuel. The effects of solvent extraction parameters were studied using response surface methodology with Box-Behnken design in an isothermal batch reactor. Physicochemical characterization, fatty acids profiling, ultimate analysis, analysis of metals and phosphorus concentration, Fourier-transform infrared spectroscopy characterization, and calorific value analyses were performed to characterize the properties of oils. Accordingly, oil yields ranged from 35.93 to 45.25%. Erucic acid (EA) was the most predominant fatty acid in all oils, accounting for 42-50%, of Derash and Yellow Dodolla oils, respectively, making Yellow Dodolla oil a super-high erucic acid oil. In comparison to the other oils, Yellow Dodolla was observed to be the least oxygenated oil, with a 7.80% oxygen content and oxygen to carbon ratio of 0.07, which may enable it to consume a very limited amount of hydrogen gas during hydrodeoxygenation in bio-jet fuel production. It was determined that, except for calcium and phosphorous levels in Tesfa, the concentrations of the metals and phosphorous were very small. Alkanes, alkenes, carboxylic acids, esters, alcohols, aromatics, and olefins were among the most significant and main functional groups identified. Our extraction and characterization results revealed that the Brassica carinata cultivars have very high oil contents, better physicochemical properties, excellent fatty acid profiles, and very low concentrations of heteroatoms (nitrogen, sulfur), metals and phosphorous concentrations, and very low level of oxygen to carbon ratios, making the oils, notably Yellow Dodolla oil, very high quality and promising alternative feedstocks for upgrading of the oils into bio-jet fuels through hydroprocessing pathway.

Development and Validation of Kompetitive Allele-Specific PCR Assays for Erucic Acid Content in Indian Mustard [Brassica juncea (L.) Czern and Coss.

Brassica juncea L. is the most widely cultivated oilseed crop in Indian subcontinent. Its seeds contain oil with very high concentration of erucic acid (≈50%). Of late, there is increasing emphasis on the development of low erucic acid varieties because of reported association of the consumption of high erucic acid oil with cardiac lipidosis. Erucic acid is synthesized from oleic acid by an elongation process involving two cycles of four sequential steps. Of which, the first step is catalyzed by β-ketoacyl-CoA synthase (KCS) encoded by the fatty acid elongase 1 (FAE1) gene in Brassica. Mutations in the coding region of the FAE1 lead to the loss of KCS activity and consequently a drastic reduction of erucic acid in the seeds. Molecular markers have been developed on the basis of variation available in the coding or promoter region(s) of the FAE1. However, majority of these markers are not breeder friendly and are rarely used in the breeding programs. Present studies were planned to develop robust kompetitive allele-specific PCR (KASPar) assays with high throughput and economics of scale. We first cloned and sequenced FAE1.1 and FAE1.2 from high and low erucic acid (<2%) genotypes of B. juncea (AABB) and its progenitor species, B. rapa (AA) and B. nigra (BB). Sequence comparisons of FAE1.1 and FAE1.2 genes for low and high erucic acid genotypes revealed single nucleotide polymorphisms (SNPs) at 8 and 3 positions. Of these, three SNPs for FAE1.1 and one SNPs for FAE1.2 produced missense mutations, leading to amino acid modifications and inactivation of KCS enzyme. We used SNPs at positions 735 and 1,476 for genes FAE1.1 and FAE1.2, respectively, to develop KASPar assays. These markers were validated on a collection of diverse genotypes and a segregating backcross progeny. KASPar assays developed in this study will be useful for marker-assisted breeding, as these can track recessive alleles in their heterozygous state with high reproducibility.

Genetic variability and regression analysis for yield and quality traits in Brassica napus

An experiment was conducted to estimate the genetic variability and regression analysis for yield and quality traits in a set of eight brassica genotypes in a randomized complete block design with three replications at The University of Agriculture Peshawar, during 2011-12 cropping season. Significant genetic variability was recorded among genotypes for plant height, pods main receme-1, pod length, seed yield plant-1, 1000-seed weight, seeds pod-1, oil content, protein content, glucosinolate content, erucic acid content, oleic acid content and linolenic acid content except for primary branch plant-1 and pods plant-1 which showed non-significant differences. Genotypes, AUP-401, AUP-402, AUP-404 and AUP-407 showed potential performance for glucosinolate content (55.1 µmol g-1), seed yield plant-1 (23.93 g), pods plant-1 (268.83), protein contents (21.1 %), erucic acid contents (42.7 %) and oil contents (53.3 %). Seed yield plant-1 was taken as a dependent variable to study the effects of many morphological yield traits on it. Branches plant-1, pods main raceme-1, pods plant-1, and seed pod-1 showed a positive effect on seed yield plant-1, while 1000-seed weight, pod length, and plant height showed a negative effect on seed yield plant-1. Seed yield plant-1 as an independent variable showed a negative effect on oil content. Protein content as an independent variable showed a positive effect on erucic acid content, while oil contents as independent variables show a negative effect on protein contents, respectively. The developed germplasm could be used in the upcoming brassica breeding programs to release high yielding, disease resistance, stress tolerance, and insect resistance varieties, which will eventually upsurge the productivity and decrease the gap between demand and domestic production of the brassica crop.

Ethnobotanical and phytopharmacological notes on Cakile maritima

Cakile maritima Scop., probably derived from the Arabic word kakeleh, is a halophyte plant belonging to the Brassicaceae family, widespread in the North African, European, Asian, and Australian coasts. It grows there and colonizes marine sands. Despite its pungent and sometimes bitter taste, it can be eaten raw or cooked. This Brassicaceae has been known since the Middle Ages for its various medicinal and therapeutic properties. Indeed, it is known in traditional medicine for its diuretic, antiscorbutic, appetizing, digestive, and purgative effects. Studies have revealed other biological, antioxidant, antibacterial, antifungal, and molluscicidal activities. The erucic acid content in its seeds is used in the treatment of demyelinating diseases. Isothiocyanates present in many Brassicaceae and glucosinolate hydrolysis products are endowed with chemopreventive and antimutagenic properties. In fact, biological tests showed that Cakile maritima has a preventive role against cancer. Moreover, the presence of an active ingredient in plant extracts with moisturizing property gives it uses for cosmetic applications and dermatological care.With its soil binding capacity, it could play an ecological role in the fight against erosion, as well as in agronomy. The cultivation of this plant would also be possible thanks to its potential for bioremediation and because of its seed erucic acid oil content, it can have significant industrial applications and become profitable economically.

Development of ultra‐high erucic acid oil in the industrial oil crop Crambe abyssinica

Erucic acid (22 : 1) is a major feedstock for the oleochemical industry. In this study, a gene stacking strategy was employed to develop transgenic Crambe abyssinica lines with increased 22 : 1 levels. Through integration of the LdLPAAT, BnFAE1 and CaFAD2-RNAi genes into the crambe genome, confirmed by Southern blot and qRT-PCR, the average levels of 18 : 1, 18 : 2 and 18 : 3 were markedly decreased and that of 22 : 1 was increased from 60% in the wild type to 73% in the best transgenic line of T4 generation. In single seeds of the same line, the 22 : 1 level could reach 76.9%, an increase of 28.0% over the wild type. The trierucin amount was positively correlated to 22 : 1 in the transgenic lines. Unlike high erucic rapeseed, the wild-type crambe contains 22 : 1 in the seed phosphatidylcholine and in the sn-2 position of triacylglycerols (5% and 8%, respectively). The transgenic line with high 22 : 1 had decreased 22 : 1 level in phosphatidylcholine, and this was negatively correlated with the 22 : 1 level at the sn-2 position of TAG. The significances of this study include (i) achieving an unprecedented level of 22 : 1 in an oil crop; (ii) disclosing mechanisms in the channelling of a triacylglycerol-specific unusual fatty acid in oil seeds; (iii) indicating potential limiting factors involved in the erucic acid biosynthesis and paving the way for further increase of this acid and (iv) development of an added value genetically modified oil crop having no risk of gene flow into feed and food crops.

Acantozero erucic acid oriental condiment mustard

Acanto is the first zero erucic acid oriental condiment mustard [Brassica juncea (L.) Czern.]. It has the same grain yield, plant height, seed protein content, seed weight, allyl glucosinolate content, and seed chlorophyll content as the check cultivar Cutlass. Both cultivars are highly resistant to blackleg disease caused by Leptosphaeria maculans (Desm.) Ces et de Not., but are susceptible to white rust race 2v caused by Albugo candida (Pers.) Kuntze. Acanto is more susceptible to white rust race 2a than is Cutlass. Acanto matures 2 d later than Cutlass, has a 2.9% lower seed oil (fixed oil) content and its seed colour is a darker yellow. Acanto was well adapted to the mustard growing areas of the Canadian prairies.Key words: Brassica juncea (L.) Czern., cultivar description, zero erucic acid oil

Analysis of QTLs for erucic acid and oil content in seeds on A8 chromosome and the linkage drag between the alleles for the two traits in Brassica napus

The history of canola breeding began with the discovery of germplasm with low erucic acid content in seeds of spring forage cultivar in the 1950's. FAE1 mutations led to a dramatic decrease of the seed erucic acid content in Arabidopsis thaliana. The products of the two FAE1 loci, BnA8.FAE1 and BnC3.FAE1, showed additive effects to the level of erucic acid content in oilseed rape. Previous research believed that the pleiotropy of FAE1 was responsible for the decrease in seed oil content along with the reduction of seed erucic acid content in the modern cultivars. TN DH population was developed from a canola cultivar Tapidor and a Chinese traditional cultivar Ningyou7. The population had been tested in 10 and 11 environments to map QTLs for the erucic acid content and oil content in seeds. As the map resolution increased, a novel QTL for seed erucic acid content was revealed, after Meta-analysis, 7 cM away from the most significant seed erucic acid content QTL where BnA8.FAE1 is located. Seven independent QTLs for seed oil content (qOC) were detected around the two seed erucic acid content QTLs (qEA) across 39.20 cM on linkage group A8. Two of the qOCs co-localized with the two qEAs, respectively, and were detected in a single environment. The other five qOCs were detected in 10 of 11 environments independent of qEAs. Alleles from Tapidor in all the QTLs at the 0-39.20 cM region contributed negative effects to either erucic acid content or oil content in seeds. Parallel, genotyping showed that on 5 of the 7 QTLs regions, Tapidor alleles had the same genotypes with that in 'Liho', the original low seed erucic acid content source. Through rounds of crossbreeding with oil-cropped cultivars and intensive selection for multi generations, Tapidor still had the inferior alleles for low seed oil content from 'Liho', the forage rape. This showed a strong linkage drag of low seed oil content, which was controlled by the five qEA-independent qOCs, with low seed erucic acid content. Ninety cultivars of B. napus from 8 countries were used to analyze the genetic drag with 9 molecular markers located in the QTL confidence intervals (24.04 cM) on linkage group A8. It was noticed that more than 46% of the cultivars with low seed erucic acid content trait remained the genotype of low seed oil content at least in one locus. Backcross and marker-assisted selection could break the genetic drag between the low oil content and erucic acid in seeds in the process for breeding modern high seed oil content canola cultivars.

Production and characterization of methyl ester sophorolipids with 22-carbon-fatty acids

In this study, various fatty acids of 18 and 22 carbons were used as substrates to produce sophorolipids in Candida bombicola ATCC 22214. Methyl esterification of erucic acid and C22-enriched rapeseed oil generated mainly acidic sophorolipids with different degrees of saturation in the fatty acid chain, which was demonstrated by structural analysis using HPLC, LC–MS and NMR spectroscopy. Regardless of methyl esterification, the rapeseed oil served as the best substrate for high production of sophorolipids among the tested. Methyl esterification also had no noticeable effect on the interfacial properties of sophorolipids. However, 22 carbons introduced in the fatty acid chain increased the hydrophobicity of sophorolipids, and therefore improved surface-active properties and biodegradability.

Resistance to cabbage seedpod weevil among selected Brassicaceae germplasm

AbstractBrassicaceae germplasm (Brassica napus L., Brassica rapa L., Brassica juncea (L.) Czern., Brassica carinata A. Braun, Sinapis alba L., Camelina sativa (L.) Crantz, Crambe species) with cultivar development potential for the prairies was evaluated for resistance to cabbage seedpod weevil (Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae)) infestation under field conditions in southern Alberta from 2001 to 2005. Relative susceptibilities were as follows: B. rapa and B. napus &gt; B. juncea = B. carinata &gt; S. alba. Although some of the germplasm evaluated varied within species in terms of glucosinolate profile, erucic acid level, oil content, and plant height, none of these factors appeared to influence the degree of C. obstrictus damage. A subset of this germplasm was also evaluated in the greenhouse. Although the canola species B. rapa sustained the highest level of damage in the field tests, it was similar to other Brassica genotypes in the greenhouse. All lines of S. alba were virtually immune to weevil attack in both field and greenhouse tests, regardless of glucosinolate profile, suggesting that other factors confer resistance in this species. Synchrony of crop development with weevil activity in the field explains some of the variability in damage observed among genotypes and illustrates the importance of combining field and greenhouse studies when assessing resistance.

Breeding Indian mustard [Brassica juncea (L.) Czern.] for cold-pressed, edible oil production—a review

Indian mustard [Brassica juncea (L.) Czern.] is a more productive oilseed than canola (B. napus L.) in hot regions of Russia, India, China, and Canada with somewhat unreliable rainfalls, whereas canola is the higher yielding species in more temperate, wetter regions. The specific agronomic features of the species, and their performance in various Australian regions are reviewed. The discovery of the genes for low erucic acid oil production in the seeds of Indian mustard began the conversion of this ancient crop to a canola-type oilseed for dry areas. Initially, many accessions were field-tested at Wagga Wagga and Canberra, but 2 seed-borne diseases, leaf and stem blight and seed rot, were destructive. Accessions from South Asia were severely damaged by the blight caused by Pseudomonas syringae pv. maculicola Young, Dye &amp; Wilkie 1978, whereas most of the cultivars from latitudes above 45°N were resistant. A phytotron procedure was developed for screening seedlings. The segregation pattern in F2 families from resistant × susceptible crosses suggested that reactions to a typical Pseudomonas isolate were controlled largely by co-dominant resistance (PsmR ) and susceptibility (PsmS ) alleles at one locus. F3 families with field resistance equal to the PsmR/PsmR parents were readily recovered, indicating that few or no modifying genes affected disease reactions. Resistant families selected from each of 6 crosses yielded 13.8% more seed (P &lt; 0.001) than the corresponding segregating and susceptible families when these were tested at Canberra and Wagga Wagga. The disease became unimportant when most entries in field trials were resistant. A seed-rotting disease caused by a yeast with distinctive ascospores closely resembling those of Nematospora sinecauda Holley, Allan-Wotjas &amp; Phipps-Todd 1984 occurred in some imported and locally grown seed samples, but was eliminated by hot water treatment of seed prior to sowing and by control of the presumed insect vector, Nysius vinitor (Bergroth), during seed maturation in the field. No previous record of the occurrence of this disease in Australia was found in the literature by a plant pathologist. The availability of breeding lines with low erucic acid seed oil, Pseudomonas resistance, and a predominance of propenyl glucosinolate in the meal permitted the development of a cold-pressed, edible oil industry by a family company (Yandilla Mustard Oil Enterprise) at Wallendbeen, NSW. The original oil has a mild nutty flavour, but now a larger proportion of the market requires a pungent, mustard-flavoured oil containing a trace of propenyl isothiocyanate, the hydrolytic product of the corresponding glucosinolate in the meal. The full-flavoured meal is sold for table mustard and pickle manufacture, as a stock feed ingredient containing approximately 30% protein and 18% oil, and for the distillation, by another small company at Cowra, NSW, of propenyl isothiocyanate, which is used as a flavouring and preservative in food, especially in Japan. This review describes the breeding of cultivars for cold-pressed oil production, as an off-shoot of the canola-grade B. juncea project. Five successively improved, Pseudomonas-resistant cultivars were developed by crossing and pedigree selection for higher yield under a range of limiting conditions, and released for cold-pressed, low erucic acid oil production. The rate of yield increase in the cultivars released between 1989 and 2001 was 2.4% per annum as judged from small plot yields of all cultivars in each of 4 years at Wallendbeen. Flowering time adjustment provided a one-off improvement, but continued progress seems possible by field selection for traits such as increased resistance to the Sclerotinia and Alternaria pathogens, resistance to acid soils, waterlogging, frost at flowering, heat and drought during seed maturation, and increased efficiency of nutrient utilisation. The nutraceutical properties of mustard oil, and the chemical differences among current B. juncea seed products, are described. Possible future developments are discussed.

Oil, erucic acid, and glucosinolate contents in winter hardy rapeseed germplasms

The US industry uses ≈18 million kg of high erucic acid oil annually, mostly from imports. Therefore, a large overall market potential exists for development of annually renewable domestic sources of erucic acid. The present research was conducted to characterize the winter hardy rapeseed germplasm for oil, erucic acid, and glucosinolate contents for use in breeding programs to develop commercial production of rapeseed. Significant variation existed among the 455 accessions of Brassica napus L. and the 44 accessions of Brassica rapa L. for oil, erucic acid, and glucosinolate contents. B. napus had significantly higher mean oil content in the seeds (37.4%) than the Brassica rapa (36.6%). The glucosinolate content was higher in napus than the rapa meal (49.2 vs. 43.8 μmol/g). The erucic acid content was higher in rapa (32.6%) than the napus accessions (26.1%). Within species, the correlation between oil and glucosinolate contents was significantly negative among the napus accessions (−0.14), but was significantly positive among rapa accessions (+0.39). The results indicate that plant material from either napus or rapa species could be used in breeding for increasing erucic acid content. Accessions with high, medium, and low contents of oil, erucic acid, and glucosinolate contents were identified.

Low pod numbers and inefficient use of radiation are major constraints to high productivity in Crambe crops

Although there have been several attempts to develop commercial production of high erucic acid (HEA) oil from Crambe since the 1950s, this species has not yet become an established crop. Recent reviews suggest that higher yields are needed to meet the market competition from HEA rapeseed oil and the on-farm competition from other crops. Our remit was to identify the major constraints to high productivity in Crambe crops. We studied Crambe crops under favorable growing conditions and focused on the duration of the developmental stages, leaf area growth, radiation interception and on the relations between assimilate sources and sinks. The radiation use efficiency (RUE) was used as a reference value and a tool to identify constraints to seed formation. The basic crop data collected and the derived relations with temperature and intercepted radiation were integrated in a simple crop model to estimate the attainable yields for a range of years. The major constraint to high productivity in Crambe appeared to be the inefficient use of radiation during seed formation. For the period from emergence to mid-flowering the RUE was 2.2 g MJ −1 against only 0.9 g MJ −1 for the subsequent period to seed ripeness. That inefficient use of radiation was shown to result from the high proportion of radiation intercepted by photosynthetically less active stems and senescing leaves. Seed filling appeared to depend on actual photosynthesis by the pods; however, pod numbers and total pod area were too small to take over crop photosynthesis from the leaves. The simulations suggested that yields were also sensitive to exceptionally low temperatures during early growth because leaf area growth was retarded and a high proportion of radiation was wasted in the period with highest receipts. According to the growth model, an average annual production of 3250 kg ha −1 was feasible for a range of years.

Detection of molecular markers associated with linolenic and erucic acid levels in spring rapeseed (Brassica napus L.)

Summary Undesirable characteristic of rapeseed oil is a relatively high level of linolenic acid (18:3), which is easily oxidized leading to rancidity and a shortened shelf life of the oil. Previous attempts to reduce linolenic acid levels in rapeseed oil through breeding have been impaired by complex genetics and strong environmental sensitivity of this trait. Therefore, our objective was to develop molecular markers for low linolenic acid that could facilitate the breeding of low linolenic rapeseed. Bulked segregant analysis was employed to identify two RAPD markers associated with 18:3 in a doubled haploid population segregating for linolenic and erucic acid levels. Based on analysis of individual DH lines, the markers RM350 and RM574, representing two independent loci, accounted for a total of 39% of the genetic variability for 18:3 in this population. The marker RM350 alone accounted for 25% genetic variation for this trait with no evidence of recombination. Significant interlocus interaction found between the markers RM350 and RM574 suggested that epistasis was involved in the genetic control of 18:3 level in this population. Another marker designated as RM322, which was independent of the other two, was found significantly associated with the erucic acid level and oil content. RAPD markers identified in this study should be a useful tool for the early detection of low linolenic, or low or high erucic acid genotypes in rapeseed breeding programs based on doubled haploids.

Agronomic characterization of some Crambe abyssinica genotypes in a locality of the Po Valley

The use of oil with a high level of erucic acid in some industrial sectors appears to offer excellent prospects from a technological and environmental point of view. This study was carried out to determine the potential of Crambe abyssinica for producing high erucic acid oil seeds in the Po Valley environment (North Italy). The productive yield of 3-year trials using six different genotypes was generally satisfactory, even though significant differences were found between the years. The different weather patterns recorded during the trials showed how emergence, flowering and seed-filling stages are particularly important phases for obtaining good yields. The grain production in these years ranged between 2.3 and 3.2 t ha −1 and were similar to that of other spring oilseed crops in our environment. The seed had an oil concentration of between 320 and 370 g kg −1, with a fatty acid composition regularly characterized by a level of erucic acid higher than 53%. This paper also reports and discusses some other seed characteristics (protein content, weight per hectolitre, thousand kernel weight, hull/seed ratio and number of seed per plant). Amongst the genotypes tested, Mario gave the highest seed and oil yields followed by Belann and C-29, whereas Mejer and Belenzian gave lower yields, especially as a result of an insufficient emergence.

Is dietary erucic acid hepatotoxic in pregnancy? An experimental study in rats and hamsters

The hypothesis that dietary erucic acid may contribute to the pathogenesis of intrahepatic cholestasis of pregnancy has been examined in pregnant rats and hamsters after prolonged feeding of diets containing 25% rapeseed oil rich in erucic acid (40% of fatty acids) or corn oil, without erucic acid. Both dietary oils were well tolerated, although weight gain was 17% to 20% less in animals receiving rapeseed oil. Rats and hamsters were studied on the last day of pregnancy and compared with age- and diet-matched nonpregnant animals. Histological examination showed no major morphologic abnormalities in liver, heart, kidneys, and adrenals. Similar microscopic deposits of fat were found in the livers and hearts of pregnant hamsters of both dietary groups. Chromatographic analysis of fatty acids in liver, heart, and kidney homogenates of hamsters and in isolated rat liver cells reflected the fatty acid composition of the dietary oils: oleic (18:1) and linoleic (18:2) acids were among the predominant fatty acids. Erucic acid was found in a higher proportion in the heart (14% by weight of total fatty acids) than in the liver (3%) and kidneys (3%) of animals fed rapeseed oil. Bile flow and biliary lipid composition was similar in rats and hamsters fed rapeseed or corn oil. Bile flow tended to be less in pregnant than in nonpregnant animals. Pregnant hamsters fed rapeseed oil tended to have the lowest bile flow. The lithogenic index of bile was slightly decreased in pregnant rats and increased in pregnant hamsters, although these proportional changes were similar for both diets. In all circumstances the lithogenic index remained below a value of 1. Biliary excretion of sulfobromophthalein (BSP) and maximal transport capacity of BSP into bile (BSP Tm) were similar in rats fed rapeseed or corn oil diets. In conclusion, no morphologic or hepatic functional abnormalities attributable to the diet could be detected in animals fed rapeseed oil with a high content of erucic acid, whereas pregnancy induced changes in bile secretion in rats and hamsters, irrespective of the diet administered. These observations are still insufficient to reject the possibility that rapeseed oil rich in erucic acid could be involved in the pathogenesis of intrahepatic cholestasis of pregnancy because dietary erucic acid could interact with a genetic metabolic predisposition to induce a disease that seems to be specific to humans.

Is dietary erucic acid hepatotoxic in pregnancy? an experimental study in rats and hamsters

The hypothesis that dietary erucic acid may contribute to the pathogenesis of intrahepatic cholestasis of pregnancy has been examined in pregnant rats and hamsters after prolonged feeding of diets containing 25% rapeseed oil rich in erucic acid (40% of fatty acids) or corn oil, without erucic acid. Both dietary oils were well tolerated, although weight gain was 17% to 20% less in animals receiving rapeseed oil. Rats and hamsters were studied on the last day of pregnancy and compared with age- and diet-matched nonpregnant animals. Histological examination showed no major morphologic abnormalities in liver, heart, kidneys, and adrenals. Similar microscopic deposits of fat were found in the livers and hearts of pregnant hamsters of both dietary groups. Chromatographic analysis of fatty acids in liver, heart, and kidney homogenates of hamsters and in isolated rat liver cells reflected the fatty acid composition of the dietary oils: oleic (18:1) and linoleic (18:2) acids were among the predominant fatty acids. Erucic acid was found in a higher proportion in the heart (14% by weight of total fatty acids) than in the liver (3%) and kidneys (3%) of animals fed rapeseed oil. Bile flow and biliary lipid composition was similar in rats and hamsters fed rapeseed or corn oil. Bile flow tended to be less in pregnant than in nonpregnant animals. Pregnant hamsters fed rapeseed oil tended to have the lowest bile flow. The lithogenic index of bile was slightly decreased in pregnant rats and increased in pregnant hamsters, although these proportional changes were similar for both diets. In all circumstances the lithogenic index remained below a value of 1.(ABSTRACT TRUNCATED AT 250 WORDS)

PERFORMANCE OF A NATURALLY OCCURRING SUBSPECIES HYBRID IN B. campestris L. var. oleifera Metzg.

A naturally occurring subspecies hybrid of the type Brassica campestris ssp. sarson Prain. ’R-500’ × B. campestris L. var. oleifera Metzg. was identified. Hybrid seed borne on R-500 plants is larger and more darkly pigmented than seed from self- and sib pollinations of R-500. Of 77 seeds selected on the basis of diameter and testa color, 60 had erucic acid levels indicating that they were hybrids between R-500 and an unknown low erucic acid type. The hybrid yielded 146% of the B. campestris var. oleifera ’Candle’ in a replicated test. Oil content of the hybrid was 2.6% lower than Candle but protein content was 4.1% higher. Yield of oil and protein per hectare was 137% and 160% of Candle, respectively. Seed borne on the hybrid is brown but crude fiber content of the meal is not significantly different from the yellow-seeded, low fiber cultivar Candle. Seed produced on hybrid plants has high erucic acid oil (28.9%) and high glucosinolate meal (95.5 μm/g). Days to maturity of the hybrid is intermediate between B. campestris and B. napus.

Composition of fatty acids and structure of triglycerides in medium and low erucic acid rapeseed

AbstractTotal triglycerides in medium (MEAR) and low (LEAR) erucic acid cultivars of rapeseed were fractionated by argentation chromatography into twelve and ten fractions, respectively. Gas liquid chromatography of the fatty acids in the triglyceride fractions and their 2‐monoglycerides was used to evaluate the structural characteristics of the individual fractions. Fractionation occurred on the basis of degree of unsaturation, molecular weight and positional characteristics. The most mobile fractions contained 34–50% of saturated fatty acids while the less mobile had 59–65% of polyunsaturated fatty acids. In the medium erucic acid oil, long chain fatty acids (C20–C22) were found in all fractions, but four fractions of low erucic acid oil were essentially free of long chain acids. Two of these fractions in the latter oil, which represented 44% of the total triglycerides, were glycerol trioleate and dioleoyllinoleoylglycerol. The majority of the 2‐positions were occupied by unsaturated C18 fatty acids, generally in the order of linoleic ≥linolenic&gt; oleic acids. The saturated and long chain fatty acids occurred predominantly in the 1‐and 3‐positions. The various fractions of medium and low erucic acid oils were similar in structural composition except that eicosenoic and erucic acids substituted for oleic acid in some external positions. Erucic acid did not appear to substitute directly for oleic acid in the 2‐position.

Crismer values and erucic acid contents of rapeseed oils

Abstract and SummaryCrismer Values of rapeseed oil extracted from different Canadian varieties are reported. Seventeen samples of oil containing up to 4.1% erucic acid gave an average value of 68.45±0.92 C with a range of 67.10 to 69.29. Crismer Values of high erucic acid oils (20~45% erucic acid) ranged from 76 to 82 C.