Phytosterols accumulation in the seeds of Linum usitatissimum L

Variation in Linseed Oil Composition: Impact of Cultivar, Cultivation System, and Year of Cultivation

Linseed oil quality depends on cultivar and agriculture practice/conditions. In this study, we analyzed the effect of the main variable, which was continuous cropping system vs. crop rotation system. The aim of this study was to compare the oil content and composition (fatty acid composition and sterol, tocochromanol, carotenoid, and phenolic contents) of two fiber-type linseed cultivars (Modran and Nike). All measurements were performed according to standard chromatographic/spectrophotometric procedures typical for oil analysis. The factors that affected the crop yield and oil quality of the tested cultivars included the cultivation system (crop rotation or continuous cropping), plant protection level (herbicide application or no herbicide application), and year of cultivation (2018 and 2019). The cultivars exhibited high oil content (35.4-42.7%) with substantial omega-3 fatty acid (α-linolenic acid) content (53.6-62.2% of total fatty acids). The primary bioactive components in all the oils were sterols (dominated by β-sitosterol), with their content reaching 5079 mg/kg, and tocochromanols, with their content reaching 679 mg/kg (dominated by γ-tocopherol), which was influenced by all of the studied factors. In contrast, carotenoids and phenolic compounds constituted a smaller fraction of the oils (up to 17 and 159 mg/kg, respectively), but their content was the most variable and was strongly dependent on the cultivation year and cultivation system (CV 21 and 37%, respectively). In summary, the results of the current study showed that continuous linseed cropping resulted in increased levels of carotenoids, phenolic compounds, and γ-tocopherol in oil. Our findings indicated that the oil content was mostly affected by the cultivar and cultivation year, while the α-linolenic acid content in the oil was also affected by plant protection practices. These findings may be helpful in predicting the composition of obtained linseed oil and applying proper cultivation technology, depending on the purpose of oil usage.

Supercritical CO2 Extraction vs. Hexane Extraction and Cold Pressing: Comparative Analysis of Seed Oils from Six Plant Species

Supercritical fluid extraction using carbon dioxide (SFE-CO2) brings a convincing advance in the production of plant oils used in cosmetics, in fortified foods and dietary supplements, and in pharmaceuticals and medicine. The SFE-CO2-extracted, hexane-extracted, and cold-pressed plant oils of pumpkin (Cucurbita pepo L.), flax (Linum usitatissimum L.), linden (Tilia sp.), poppy (Papaver somniferum L.), apricot (Prunus armeniaca L.), and marigold (Calendula officinalis L.) seeds were investigated in terms of oil yield, fatty acid composition, unsaponifiable matter yield and composition, and the antioxidant activity of unsaponifiable matter. SFE-CO2 proved to be the preferred extraction method for four out of six plant materials, especially for seeds with lower oil content. However, for seeds with higher oil content, such as apricots, cold pressing is a viable alternative. A comparison of fatty acid composition did not reveal significant differences between extraction techniques. SFE-CO2 extraction improved the total phytosterol content of oils, especially pumpkin seed oil. A high variability in the antioxidant potential of the unsaponifiable matter studied was determined, with pumpkin seed oil showing the highest antioxidant activity. A correlation analysis was performed between unsaponifiable composition and antioxidant activity, and showed statistically significant correlations with squalene, cycloartenol, and an unidentified compound. This is the first comparison of the phytosterol compositions of linseed, apricot, linden, and marigold. Through continued optimization, SFE-CO2 has the potential to revolutionize the production of plant oils and provide a sustainable and efficient alternative.

Egg vs. Oil in the Cookbook of Plasters: Differentiation of Lipid Binders in Wall Paintings Using Gas Chromatography-Mass Spectrometry and Principal Component Analysis

Wall paintings are integral to cultural heritage and offer rich insights into historical and religious beliefs. There exist various wall painting techniques that pose challenges in binder and pigment identification, especially in the case of egg/oil-based binders. GC-MS identification of lipidic binders relies routinely on parameters like the ratios of fatty acids within the plaster. However, the reliability of these ratios for binder identification is severely limited, as demonstrated in this manuscript. Therefore, a more reliable tool for effective differentiation between egg and oil binders based on a combination of diagnostic values, specific markers (cholesterol oxidation products), and PCA is presented in this study. Reference samples of wall paintings with egg and linseed oil binders with six different pigments were subjected to modern artificial ageing methods and subsequently analysed using two GC-MS instruments. A statistically significant difference (at a 95% confidence level) between the egg and oil binders and between the results from two GC-MS instruments was observed. These discrepancies between the results from the two GC-MS instruments are likely attributed to the heterogeneity of the samples with egg and oil binders. This study highlights the complexities in identifying wall painting binders and the need for innovative and revised analytical methods in conservation efforts.

Trends and advances in pre- and post-harvest processing of linseed oil for quality food and health products

Linseed is an ancient crop used for diverse purposes since the beginning of civilization. In recent times, linseed has emerged as a superfood due to its high content of health-promoting omega-3 fatty acids and other bioactive compounds. Among primary health effects, it has potential to manage hypertension, diabetes, osteoporosis, atherosclerosis, cancer, arthritis, neurological, cardiovascular diseases including blood cholesterol levels, constipation, diarrhea, and autoimmune disorders etc. due to the presence of omega-3 fatty acid, lignans, high dietary fibers, and proteins, whereas, secondary health effects comprise of relieving from various skin disorders. Due to these health-beneficial properties, interest in linseed oil necessitates the intensification of research efforts on various aspects. These include cultivation technology, varietal and genetic improvement, post-harvest processing, profiling of nutrients and bioactive compounds, pre-clinical and clinical studies, etc. The present review discussed the advances in linseed research including pre- and post-harvest processing. However, focus on the bioactive compounds present in linseed oil and their health effects are also presented. Linseed cultivation, pre- and post-harvest processing aspects are covered including climatic, edaphic, agronomic factors, type of cultivar and storage conditions etc, which impact the overall oil yield and its nutritional quality. Various emerging applications of linseed oil in functional food, nutraceutical, pharmaceutical, and cosmeceutical preparations were also presented in detail. Further, recommendations were made on linseed oil research in the field of genetics, breeding germplasm resources and genome editing for exploring its full applications as a nutrition and health product.

The ability of supercritical CO2 carrot and pumpkin extracts to counteract inflammation and oxidative stress in RAW 264.7 macrophages stimulated with LPS or MDA-MB-231 cell-conditioned media

Supercritical fluid extraction with CO2 (SFE) is an alternative technology to conventional solvent extraction (CSE), to obtain food-grade bioactives from plants. Here, SFE and CSE extracts from carrot and pumpkin matrices, impregnated with hempseed or flaxseed oil as co-solvents, were characterized by HPLC and GC-MS, and their ability to counteract the inflammatory and oxidative phenomena underlying the onset of several pathologies was assessed in vitro. All extracts showed dose-dependent anti-inflammatory potential and demonstrated an ability to interfere with the pro-inflammatory effects of breast cancer cell-conditioned media, and to inhibit reactive oxygen species (ROS) accumulation and nitrite production (NP) in lipopolysaccharide-stimulated macrophages. Nuclear factor-erythroid-2-related factor 2 (Nrf2) is involved in these response mechanisms, as highlighted by the increased mRNA levels of its target genes revealed by quantitative real-time PCR analyses. NP and ROS concentrations negatively correlated with α-tocopherol and most carotenoids, but positively with the total tocopherol/total carotenoid ratio, suggesting an idiosyncratic effect of these bioactives on cell responses and emphasizing the need to focus on extract constituents' interactions.

A Review of the Potential Benefits of Herbal Medicines, Small Molecules of Natural Sources, and Supplements for Health Promotion in Lupus Conditions

The Latin word lupus, meaning wolf, was in the medical literature prior to the 1200s to describe skin lesions that devour flesh, and the resources available to physicians to help people were limited. The present text reviews the ethnobotanical and pharmacological aspects of medicinal plants and purified molecules from natural sources with efficacy against lupus conditions. Among these molecules are artemisinin and its derivatives, antroquinonol, baicalin, curcumin, emodin, mangiferin, salvianolic acid A, triptolide, the total glycosides of paeony (TGP), and other supplements such as fatty acids and vitamins. In addition, medicinal plants, herbal remedies, mushrooms, and fungi that have been investigated for their effects on different lupus conditions through clinical trials, in vivo, in vitro, or in silico studies are reviewed. A special emphasis was placed on clinical trials, active phytochemicals, and their mechanisms of action. This review can be helpful for researchers in designing new goal-oriented studies. It can also help practitioners gain insight into recent updates on supplements that might help patients suffering from lupus conditions.

Effect of Ferulic Acid and Its Derivatives on Cold-Pressed Flaxseed Oil Oxidative Stability and Bioactive Compounds Retention during Oxidation

Ferulic acid (FA) is a naturally occurring phenolic antioxidant that is widely used in the food, pharmaceutical, and cosmetic industries due to its low toxicity. Its derivatives also find numerous industrial applications and may have even higher biological activity than ferulic acid. In this study, the effect of the addition of FA and its derivatives-including vanillic acid (VA), dihydroferulic acid (DHFA), and 4-vinylguaiacol (4-VG)-on the oxidative stability of cold-pressed flaxseed oil and the degradation of bioactive compounds during oxidation was investigated. The results showed that FA and its derivatives affected the oxidative stability of flaxseed oil, but their antioxidant activity depended on the concentration (25-200 mg/100 g oil) and temperature of treatment (60-110 °C). Based on Rancimat test results, flaxseed oil oxidative stability predicted at 20 °C increased linearly with ferulic acid concentration, while its derivatives effectively prolonged the induction time at lower concentrations (50-100 mg/100 g oil). The addition of phenolic antioxidants (80 mg/100 g) generally showed a protective effect against polyunsaturated fatty acids (DHFA and 4-VG), sterols (4-VG), tocols (DHFA), squalene, and carotenoids (FA). The exception was VA, which increased the degradation of most bioactive compounds. It is believed that adding properly composed mixtures of FA and its derivatives (DHFA and 4-VG) can extend the shelf life of flaxseed oil and provide nutritional benefits.

A molecular insight into the lipid changes of pig Longissimus thoracis muscle following dietary supplementation with functional ingredients

In this work, the Longissimus thoracis pig skeletal muscle was used as a model to investigate the impact of two different diets, supplemented with n-3 polyunsaturated fatty acids from extruded linseed (L) and polyphenols from grape skin and oregano extracts (L+P), on the lipidomic profile of meat. A standard diet for growing-finishing pigs (CTRL) was used as a control. Changes in lipids profile were investigated through an untargeted lipidomics and transcriptomics combined investigation. The lipidomics identified 1507 compounds, with 195 compounds fitting with the MS/MS spectra of LipidBlast database. When compared with the CTRL group, the L+P diet significantly increased 15 glycerophospholipids and 8 sphingolipids, while the L diet determined a marked up-accumulation of glycerolipids. According to the correlations outlined between discriminant lipids and genes, the L diet may act preventing adipogenesis and the related inflammation processes, while the L+P diet promoted the expression of genes involved in lipids' biosynthesis and adipogenic extracellular matrix formation and functioning.

The quality and antioxidant elucidation of germinated flaxseed treated with acidic electrolyzed water

The endogenous fortification of antioxidant lipid concomitants in flaxseed was imperative to improve the oxidative stability of α-linolenic acid (ALA) in flaxseed and flaxseed oil upon processing, storage and gastrointestinal digestion. The comparative effects of acidic electrolyzed water (ACEW) and tap water (TW) on the triglyceride configuration, typical lipid concomitants, and antioxidant properties of flaxseed were conducted during 0-5 days of germination. The results showed that ACEW enhanced the germination rate of flaxseed by 18.25% and simultaneously suppressed the dynamic depletion of ALA by 5.32% when compared with TW (p < .05). The total phenolic acids, lignans, and flavonoids were effectively accumulated in flaxseed following ACEW-mediated germination with the further increase by 4.82%, 15.48%, and 8.22% in comparison with those induced by TW (p < .05). The total contents of cyclolinopeptides in flaxseed progressively dropped following either ACEW or TW treatment, a slighter decrease by 5.59% for flaxseed treated by ACEW than that by TW. Notably, the maximum accumulation of tocopherols and phytosterols had been early obtained for flaxseed treated with ACEW for 2-3 days due to the de novo synthesis or intermolecular conformational transition (p < .05). Most importantly, ACEW-mediated germination led to higher increment of the thermal oxidative stability and antioxidant properties of flaxseed and flaxseed oil in comparison to TW. In brief, the initial oxidation temperature increased by 7.09% and 3.06% (p < .05), and the antioxidant activities as evaluated by DPPH, ABTS, and FRAP values raised by 3.86%-28.07% and 4.21%-9.18% (p < .05), respectively. These findings clarify that the germination especailly mediated by ACEW could be an effective method to further optimize the nutritional and functional properties of flaxseed through reconstructing the endogenous antioxidant system.

Protective Effect of Tunisian Flaxseed Oil against Bleomycin-Induced Pulmonary Fibrosis in Rats

The aims of this study are to investigate the preventive effect of flaxseed oil (FO) on bleomycin (BLM)-induced pulmonary fibrosis (PF). Thirty adult male Wistar rats (180-220 g) were randomly divided into three groups. The control group (G1) received no treatment, the group (G2) received only intratracheally BLM, and the group (G3) received FO (2 mL/kg body weight) once a day for 60 days + BLM (4 mg/kg body weight "bw"). Our results demonstrated that FO protected against BLM-induced PF, by increasing proline, fructose, glucose, glyceride, choline, lactate, and malate metabolites in bronchoalveolar lavage fluid (Balf) which are involved in anti-inflammatory reactions. Also, FO-treatment reduced the score of fibrosis and the inflammatory index and revealed a decrease in tumor growth factor beta (TGFβ) density in alveoli, inflammatory infiltrate and fibrocytes, comparatively to the BLM group. As well, our data demonstrated that acute BLM-induced fibrosis was accompanied by an oxidative stress in lung tissue as assessed by an increase of lipid peroxidation as well as antioxidant enzyme activities depletion such as superoxide dismutase (SOD) and catalase (CAT). The FO treatment reversed all disturbances of BLM-induced oxidative stress parameters, and increased fatty acids levels promoting anti-inflammatory reactions especially in erythrocytes (linoleic, α-linolenic, docosapentaenoic acids).

Nigella sativa, a traditional Tunisian herbal medicine, attenuates bleomycin-induced pulmonary fibrosis in a rat model

The present study investigated the effects of Nigella sativa oil (NSO) on bleomycin (BLM)-induced lung fibrosis in rats. The rat model of pulmonary fibrosis (PF) was established by intratracheal instillation of BLM, and the effect of 1ml/kg oral NSO treatment once daily observed. The effect of NSO was studied over a period of 50daysusing 1H RMN analysis on the urine and broncho alveolar lavage fluid (Balf) of the rats. Histopathological (inflammation and fibrosis) and immunohistochemical (TGF-β1 density) changes were evaluated. Results found that the BLM group showed a significant increase in inflammatory index (II), fibrosis score (FS) and TGF-β1 distribution in the lung inflammatory infiltrate, accompanied by a decreased urinary secretion of Krebs cycle intermediates, including acetate, pyruvate, carnitine, trimethylamine-N-oxide and succinate. However, at the same time point, NSO treated rats had a reduced II and FS, and had an increased urinary secretion of histidine, fumarate, allantoin and malate. In conclusion, NSO treatment attenuated the effects of BLM-induced PF, by supporting lung, liver and kidney activity in resisting PF. These findings provide an insight into the preventive and therapeutic potential of NSO in the treatment of PF.

Therapeutic effect of flaxseed oil on experimental pulmonary fibrosis induced by bleomycin in rats

Pulmonary fibrosis is a chronic progressive disorder in which excessive deposition of extracellular matrix leads to irreversible scarring to interstitial lung tissue. In this study, we search to evaluate the therapeutic effect of flaxseed oil (FO) in experimental bleomycin (BLM)-induced pulmonary fibrosis. During our study, 30 male Wistar rats (weight range, 180–220 g) were divided into three groups: the control group (W) received no treatment; the second group (C) received BLM; and the third group (T) received BLM and FO for 21 days. Metabolites present in the bronchoalveolar lavage fluid (BALF) marking the changes obtained following treatment with FO were determined, histological changes in the lungs were evaluated, fatty acids present in lungs and erythrocytes of rats groups were determined by gas chromatography, and oxidative stress and antioxidant enzyme activity in the lung tissue were also recorded. Our results displayed that rat body weight decreased while fibrosis score and inflammatory index in lung tissue were significantly increased after bleomycin instillation. Administration of bleomycin followed by FO treatment reduced bleomycin-induced weight loss, increased proline, glucose, and glycerid rates in BALF and which are characterized by their anti-inflammatory effect and confirming the histological results proved by a decrease in inflammatory index and fibrosis score. This oil also significantly reduced thiobarbitunic acid reactive substance levels in the lungs of rats and increased levels of SOD and CAT and increased fatty acids levels promoting anti-inflammatory reactions especially in erythrocytes (linoleic, arachidonic, docosapentaenoic, and dihomo-γ-linoleic acids). In conclusion, these findings indicate that FO treatment significantly attenuated the increased pulmonary damage induced by bleomycin.

New strategies for the use of Linum usitatissimum cell factories for the production of bioactive compounds

In this work, suspension-cultured cells of Linum usitatissimum L. were used to evaluate the effect of two types of cyclodextrins, β-glucan and (Z)-3-hexenol separately or in combination on phytosterol and tocopherol production. Suspension-cultured cells of L. usitatissimum were able to produce high levels of phytosterols in the presence of 50 mM methylated-β-cyclodextrins (1325.96 ± 107.06 μg g dry weight(-1)) separately or in combination with β-glucan (1278.57 ± 190.10 μg g dry weight(-1)) or (Z)-3-hexenol (1507.88 ± 173.02 μg g dry weight(-1)), being cyclodextrins able to increase both the secretion and accumulation of phytosterols in the spent medium, whereas β-glucan and (Z)-3-hexenol themselves only increased its intracellular accumulation. Moreover, the phytosterol values found in the presence of hydroxypropylated-β-cyclodextrins were lower than those found in the presence of methylated-β-cyclodextrins in all cases studied. However, the results showed that the presence of methylated-β-cyclodextrins did not increase the tocopherols production and only an increase in tocopherol levels was observed when cells were elicited with 50 mM hydroxypropylated-β-cyclodextrins in combination with β-glucan (174 μg g dry weight(-1)) or (Z)-3-hexenol (257 μg g dry weight(-1)). Since the levels of tocopherol produced in the combined treatment were higher than the sum of the individual treatments, a synergistic effect between both elicitors was assumed. To sum up, flax cell cultures elicited with cyclodextrins alone or in combination with β-glucan or (Z)-3-hexenol were able produce phytosterols and tocopherols, and therefore, these elicited suspension-cultured cells of L. usitatissimum can provide an alternative system, which is at the same time more sustainable, economical and ecological for their production.

Evolutionary trails of plant steroid genes

Plant steroids - brassinosteroids (BRs) and their precursors, phytosterols - play a major role in plant growth, development, stress tolerance, and have high potential for agricultural applications. Currently, this prospect is limited by a lack of information about their evolution and expression dynamics (spatial and temporal) across plant species. The increasing number of sequenced genomes offers an opportunity for evolutionary studies that might help to prioritize functional analyses with the aim to improve crop yield and stress tolerance. In this review we provide a glimpse of the origin, evolution, and functional conservation of phytosterol and BR genes in the green plant lineage using comparative sequence and expression analyses of publicly available datasets.

Changes in phospholipid composition, protein content and chemical properties of flaxseed oil during development

The aim of the present research is to investigate the effect of harvest date on the composition of flaxseed. Samples were collected at regular intervals from 7 to 56 days after flowering (DAF) and analyzed for phospholipid composition, storage protein content and chemical properties. Phospholipid (PL) percentage of the total lipid decreased from 32.72% on the 7th DAF to 2.55% on the 56th DAF. The most phospholipids present in flaxseed were phosphatidylinositol (PI), phosphatidylethanolamine (PE) and lysophosphatidylcholine (LPC) which were highly unsaturated and rich in linolenic and linoleic acids, comprising together 60% of the total fatty acids. Chemical investigation of flaxseed oil showed overall a decrease in UV absorbance (K(232) and K(270)), acid value, free fatty acid content and an increase in peroxide value and storage protein content with development. At full maturity, flaxseed contained 29% proteins on a dry weight basis (DW %).

Characteristics and pathways of bioactive 4-desmethylsterols, triterpene alcohols and 4α-monomethylsterols, from developing Tunisian cultivars and wild peanut (Arachis hypogaea L.)

Seven 4-desmethylsterols, five triterpene alcohols and three 4α-monomethylsterols were identified by GC-MS during the development of wild peanut, which is Arbi (AraA), and cultivars peanut, which are Trabelsia (AraT) and Chounfakhi (AraC). Our results showed that the maximum level of 4-desmethylsterols (881.07 mg/100 g of oil) was reached at 12 days after flowering (DAF) date of peanut plant in AraA, as well as the highest level of triterpene alcohols (31.51 mg/100 g of oil) was reached at 23 DAF in AraA, whilst, the highest level of 4α-monomethylsterols (15.11 mg/100 g of oil) was reached at 41 DAF in AraC. Herein, the level of triterpene alcohols and 4α-monomethylsterols was overwhelmed by the amount of 4-desmethylsterols at each stage of peanut maturity. Differences were observed in each sterol contents among the studied cultivars and wild one especially in immature stage.

A dynamic role for sterols in embryogenesis of Pisum sativum

Molecular roles of sterols in plant development remain to be elucidated. To investigate sterol composition during embryogenesis, the occurrence of 25 steroid compounds in stages of developing seeds and pods of Pisum sativum was examined by GC-MS analysis. Immature seeds containing very young embryos exhibited the greatest concentrations of sterols. Regression models indicated that the natural log of seed or pod fr. wt was a consistent predictor of declining sterol content during embryonic development. Although total sterol levels were reduced in mature embryos, the composition of major sterols sitosterol and campesterol remained relatively constant in all 12 seed stages examined. In mature seeds, a significant decrease in isofucosterol was observed, as well as minor changes such as increases in cycloartenol branch sterols and campesterol derivatives. In comparison to seeds and pods, striking differences in composition were observed in sterol profiles of stems, shoots, leaves, flowers and flower buds, as well as cotyledons versus radicles. The highest levels of isofucosterol, a precursor to sitosterol, occurred in young seeds and flower buds, tissues that contain rapidly dividing cells and cells undergoing differentiation. Conversely, the highest levels of stigmasterol, a derivative of sitosterol, were found in fully-differentiated leaves while all seed stages exhibited low levels of stigmasterol. The observed differences in sterol content were correlated to mRNA expression data for sterol biosynthesis genes from Arabidopsis. These findings implicate the coordinated expression of sterol biosynthesis enzymes in gene regulatory networks underlying the embryonic development of flowering plants.

Comparison of the concentrations of long-chain alcohols (policosanol) in three Tunisian peanut varieties (Arachis hypogaea L.)

Policosanol (PC) is a mixture of high molecular weight aliphatic primary alcohols. Literature about the contents and compositions of PC derived from peanut varieties is scarce. Total PC composition and content in whole peanut grain samples from three varieties of peanut (two cultivars, AraC and AraT, and a wild one, AraA) were identified using a gas chromatograph system coupled with a mass spectrophotometer. The results show that, qualitatively, 21 components of peanut aliphatic alcohols were identified (C14-C30). Besides (C18=), the results exhibited a previously unreported mixture of PC compositions in the peanuts: the unsaturated PC (UPC), which are (C20=), (C21=), (C22=), and (C24=). The main components of total PC in Tunisian peanut kernels are docosanol (C22), (Z)-octadec-9-en-1-ol (C18=), hexadecanol (C16), and octadecanol (C18). Quantitatively, the total PC content of the whole peanut samples varied from 11.18 to 54.19 mg/100 g of oil and was higher than those of beeswax and whole sugar cane, which are sources of dietary supplements containing policosanol.

Gas chromatography-mass spectrometry screening for phytochemical 4-desmethylsterols accumulated during development of Tunisian peanut kernels (Arachis hypogaea L.)

4-Desmethylsterols, the main component of the phytosterol fraction, have been analyzed during the development of Tunisian peanut kernels ( Arachis hypogaea L.), Trabelsia (AraT) and Chounfakhi (AraC), which are monocultivar species, and Arbi (AraA), which is a wild species, by gas chromatography-mass spectrometry. Immature wild peanut (AraA) showed the highest contents of beta-sitosterol (554.8 mg/100 g of oil), campesterol (228.6 mg/100 g of oil), and Delta(5)-avenasterol (39.0 mg/100 g of oil) followed by peanut cultivar AraC with beta-sitosterol, campesterol, and Delta(5)-avenasterol averages of 267.7, 92.1, and 28.6 mg/100 g of oil, respectively, and similarly for AraT 309.1, 108.4, and 27.4 mg/100 g of oil, respectively, were found. These results suggest that, in immature stages, phytosterol contents can be important regulator factors for the functional quality of peanut oil for the agro-industry chain from plant to nutraceuticals.

The sterol methyltransferases SMT1, SMT2, and SMT3 influence Arabidopsis development through nonbrassinosteroid products

Plant sterols are structural components of cell membranes that provide rigidity, permeability, and regional identity to membranes. Sterols are also the precursors to the brassinosteroid signaling molecules. Evidence is accumulating that specific sterols have roles in pattern formation during development. COTYLEDON VASCULAR PATTERNING1 (CVP1) encodes C-24 STEROL METHYLTRANSFERASE2 (SMT2), one of three SMTs in Arabidopsis (Arabidopsis thaliana). SMT2 and SMT3, which also encodes a C-24 SMT, catalyze the reaction that distinguishes the synthesis of structural sterols from signaling brassinosteroid derivatives and are highly regulated. The deficiency of SMT2 in the cvp1 mutant results in moderate developmental defects, including aberrant cotyledon vein patterning, serrated floral organs, and reduced stature, but plants are viable, suggesting that SMT3 activity can substitute for the loss of SMT2. To test the distinct developmental roles of SMT2 and SMT3, we identified a transcript null smt3 mutant. Although smt3 single mutants appear wild type, cvp1 smt3 double mutants show enhanced defects relative to cvp1 mutants, such as discontinuous cotyledon vein pattern, and produce novel phenotypes, including defective root growth, loss of apical dominance, sterility, and homeotic floral transformations. These phenotypes are correlated with major alterations in the profiles of specific sterols but without significant alterations to brassinosteroid profiles. The alterations to sterol profiles in cvp1 mutants affect auxin response, demonstrated by weak auxin insensitivity, enhanced axr1 auxin resistance, ectopically expressed DR5:beta-glucuronidase in developing embryos, and defective response to auxin-inhibited PIN2-green fluorescent protein endocytosis. We discuss the developmental roles of sterols implied by these results.