Plant Oil Production Research Articles

Significance of Tissue Culture in Medicinal Plant Conservation and enhancement of Secondary metabolites by Homoeopathic intervention: A Narrative review

Aim: The objective of this study is to explore the potential of homoeopathic remedies in enhancing the biosynthesis of secondary metabolites in endangered medicinal plants. Background: Plants serve as a valuable source of medicine. Plant-based medicines are known for their simplicity, efficiency, and a broad range of activity with well-documented preventative or therapeutic effects. Secondary metabolites are active chemical components found in plants that are responsible for their medicinal properties. However, population growth, increased demand, illicit trafficking is driving the depletion of medicinal plants, and many are on the verge of extinction. The synthesis of phytochemicals in plants for medicinal purpose can be improved through various tissue culture techniques and homoeopathic remedies have been found to boost the generation of secondary metabolites. Methodology and Results: A comprehensive review of the scientific literature was carried out by searching through various databases, including Scopus, PubMed, Wiley, Google Scholar. Numerous investigations were conducted to assess the impact of homoeopathic remedies on the growth, phytochemical composition, and essential oil production of various medicinal plants. The most studied homoeopathic preparations were Phosphorus, Sulphur, and Silicea. Homoeopathic preparations were observed to improve photosynthetic rates by distributing greater amounts of photo-assimilated substances in the leaves, ultimately leading to enhanced growth. Homoeopathic medications work on the initial substances like pyruvic acid, ornithine and proline that contribute to the formation of shikimic acid and acetate, while providing the vital energy needed for plants to grow and flourish. These processes generate organic compounds that serve as precursors for various categories of secondary metabolites. Conclusion, Significance, and Impact of the study: Overall, the results suggest that homoeopathic preparations can positively impact the essential oil yield, growth, phytochemical profile of medicinal plants and expanded possibilities for the synthesis of pharmacologically and biologically active compounds. Research into applying homoeopathy to grow medicinal plants is highly relevant, as it's a long-standing practice aiming to optimize production and improve chemical constituent quality.

Enhancing growth, vitality, and aromatic richness: unveiling the dual magic of silicon dioxide and titanium dioxide nanoparticles in Ocimum tenuiflorum L.

Ocimum tenuiflorum, commonly known as "Holy basil," is renowned for its notable medicinal and aromatic attributes. Its unique fragrance attributes to specific volatile phytochemicals, primarily belonging to terpenoid and/or phenylpropanoid classes, found within their essential oils. The use of nanoparticles (NPs) in agriculture has attracted attention among plant researchers. However, the impact of NPs on the modulation of morpho-physiological aspects and essential oil production in medicinal plants has received limited attention. Consequently, the present study aimed to explore the effect of silicon dioxide (SiO2) and titanium dioxide (TiO2) nanoparticles at various concentrations (viz., DDW (control), Si50+Ti50, Si100+Ti50, Si100+Ti100, Si200+Ti100, Si100+Ti200 and Si200+Ti200 mg L-1) on growth, physiology and essential oil production of O. tenuiflorum at 120 days after planting (DAP). The results demonstrated that the combined application of Si and Ti (Si100+Ti100 mg L-1) exhibited the most favourable outcomes compared to the other combinational treatments. This optimal treatment significantly increased the vegetative growth parameters (root length (33.5%), shoot length (39.2%), fresh weight (62.7%) and dry weight (28.5%)), photosynthetic parameters, enzymatic activities (nitrate reductase and carbonic anhydrase), the overall area of PGTs (peltate glandular trichomes) and essential oil content (172.4%) and yield (323.1%), compared to the control plants. Furthermore, the GCMS analysis showed optimal treatment (Si100+Ti100) significantly improved the content (43.3%) and yield (151.3%) of eugenol, the primary active component of the essential oil. This study uncovers a remarkable and optimal combination of SiO2 and TiO2 nanoparticles that effectively enhances the growth, physiology, and essential oil production in Holy basil. These findings offer valuable insights into maximizing the potential benefits of its use in industrial applications.

Production of Single-Cell Oil from a Local Isolate Bacillus subtilis Using Palm Fronds.

This study, conducted at the Department of Biology, University of Anbar, Iraq, focuses on addressing the escalating issue of contamination and aims to acquire microbial oils to alleviate the global shortage in plant and animal oil production, utilizing environmental waste as a carbon source to reduce global pollution and select efficient local bacterial isolates of Bacillus subtilis for the production of single-cell oil (SCO) using local soil and environmental waste as a carbon source. Four isolates were selected as the best in producing single-cell oil, with the isolate with code C4 standing out as it recorded the highest production. It is worth noting that all these isolates belong to the bacteria type Bacillus subtilis. Palm fronds were found to be the most suitable environmental residue for SCO production compared to other waste materials (wheat straw and wheat bran). Submerged cultures were used to improve SCO production, with optimal conditions determined as pH 7, a temperature of 30°C, carbon source concentration of 3 g/100 ml, inoculum volume of 3 ml/100 ml, inoculum density of 20 × 107 cells, and an incubation period of 72 hours. The Soxhlet extraction method was used to obtain the oil, which was found to contain high percentages of unsaturated fatty acids, particularly linoleic acid (46.030%) and palmitoleic acid (16.579%). The oil was highly soluble in chloroform and ethanol but insoluble in water. The saponification test indicated the potential for soap production from the oil. This comprehensive research addresses the need for locally sourced and sustainable SCO production, offering insights into the selection of efficient bacterial isolates, the optimization of cultivation conditions, and the valuable properties of the resulting SCO. The significance of this study lies in the production of single-cell oil from soil-isolated Bacillus subtilis bacteria for use in food applications.

Biostimulant Application Alleviates the Negative Effects of Deficit Irrigation and Improves Growth Performance, Essential Oil Yield and Water-Use Efficiency of Mint Crop

The scarcity of water is limiting crop production and is one of the most important stressors that severely affects crop yield, and it may also decrease the quality of the final products. Most of the medicinal and aromatic plants are considered resilient to water stress and constitute a sustainable choice for crop production in arid and semiarid conditions. In the present study, we examined the effect of scheduled deficit irrigation (e.g., I1: 40% of field capacity); I2: 70% of field capacity; and I3: 100% of field capacity) combined with biostimulant application (four different products that consisted of nitrogenous compounds and carboxylic acids (M1); nitrogenous compounds and seaweed extracts (M2); humic and fulvic acids and seaweed extracts (M3); and CaO, SiO2, calcium mobilization and translocation factor and microminerals (M4)) on crop performance and essential oil production of mint plants (Mentha arvensis L.). Our aim was to define an irrigation regime that increases water-use efficiency and the biostimulant products that alleviate water stress effects. Our results indicate that moderate deficit irrigation (I2 treatment) and biostimulants that contained seaweed extracts and nitrogenous compounds and humic and fulvic acids (M2 and M3 treatments, respectively) significantly improved yield parameters in terms of fresh and dry herb yield and essential oil production. Moreover, the same biostimulant treatments significantly increased water-use efficiency of mint crops based on the various yield parameters tested in this study. In conclusion, our results indicate that selection of proper biostimulatory products may allow to apply deficit irrigation regimes in mint cultivation without compromising the crop performance in terms of both biomass production and essential oil yield. Therefore, the combination of these agronomic tools could facilitate water saving strategies in arid and semiarid regions and contribute to the sustainable management of water resources.

Phospholipid:diacylglycerol acyltransferase1-overexpression stimulates lipid turnover, oil production and fitness in cold-grown plants

BackgroundExtensive population growth and climate change accelerate the search for alternative ways of plant-based biomass, biofuel and feed production. Here, we focus on hitherto unknow, new promising cold-stimulated function of phospholipid:diacylglycerol acyltransferase1 (PDAT1) – an enzyme catalyzing the last step of triacylglycerol (TAG) biosynthesis.ResultOverexpression of AtPDAT1 boosted seed yield by 160% in Arabidopsis plants exposed to long-term cold compared to standard conditions. Such seeds increased both their weight and acyl-lipids content. This work also elucidates PDAT1’s role in leaves, which was previously unclear. Aerial parts of AtPDAT1-overexpressing plants were characterized by accelerated growth at early and vegetative stages of development and by biomass weighing three times more than control. Overexpression of PDAT1 increased the expression of SUGAR-DEPENDENT1 (SDP1) TAG lipase and enhanced lipid remodeling, driving lipid turnover and influencing biomass increment. This effect was especially pronounced in cold conditions, where the elevated synergistic expression of PDAT1 and SDP1 resulted in double biomass increase compared to standard conditions. Elevated phospholipid remodeling also enhanced autophagy flux in AtPDAT1-overexpresing lines subjected to cold, despite the overall diminished autophagy intensity in cold conditions.ConclusionsOur data suggest that PDAT1 promotes greater vitality in cold-exposed plants, stimulates their longevity and boosts oilseed oil production at low temperature.

Combining orthogonal plant and non-plant fatty acid biosynthesis pathways for efficient production of microbial oil enriched in nervonic acid in Yarrowia lipolytica

Nervonic acid has proven efficacy in brain development and the prevention of neurodegenerative diseases. Here, an alternative and sustainable strategy for nervonic acid-enriched plant oil production was established. Different β-ketoacyl-CoA synthases and heterologous Δ15 desaturase were co-expressed, combined with the deletion of the β-oxidation pathway to construct orthogonal plant and non-plant nervonic acid biosynthesis pathways in Yarrowia lipolytica. A “block-pull-restrain” strategy was further applied to improve the supply of stearic acid as the precursor of the non-plant pathway. Then, lysophosphatidic acid acyltransferase from Malania oleifera (MoLpaat) was identified, which showed specificity for nervonic acid. Endogenous LPAAT was exchanged by MoLPAAT resulted in 17.10 % nervonic acid accumulation. Finally, lipid metabolism was engineered and cofactor supply was increased to boost the lipid accumulation in a stable null-hyphal strain. The final strain produced 57.84 g/L oils with 23.44 % nervonic acid in fed-batch fermentation, which has the potential to substitute nervonic acid-enriched plant oil.

Modification of Tyre Rubber Crumb with Wastes of Plant Oil Production

Recovery of fat-and-oil production wastes will reduce the technogenic impact on the environment, as well as involve them in a new production cycle as a secondary material resource. As part of solving this problem, the possibilities of using fat-and-oil production wastes in the production of a tyre reclaim and a modified tyre reclaim are considered. In the course of the studies, the fat-and-oil industry wastes’ sorption characteristics are determined, and in relation to oils in static and dynamic conditions, the spent reagent reclamation ways are determined. The authors obtained a tyre reclaim and a modified tyre reclaim using the fat-and-oil industry wastes (soap stock, diatomite, bleaching clay, and fatty acids isolated from soap stock). In this work, the authors studied the possibility of using the fat-and-oil industry wastes in the formulations of a tyre reclaim and a modified tyre reclaim. Extended physical and mechanical tests of experimental rubbers led to the conclusion that it is most expedient to use the fat-and-oil industry wastes in the formulation of rubber compounds for production of sleeper pads for railroad tracks, since when using a tyre reclaim and a modified tyre reclaim, the indicators of rubber properties practically do not change and comply with control standards.

Steam-mediated foliar application of catechol and plant growth regulators enhances the growth attributes, photosynthesis, and essential oil production of lemongrass [Cymbopogon flexuosus (Steud.) Wats

Improvement in growth, yield, and essential oil production of plants through foliar application of PGRs and elicitors has been extensively studied in the authors' laboratory. Instead of using a sprayer machine, a new steam-spray method was applied to explore the possibility that if we could increase the growth, yield, and EO production of lemongrass. The foliage of lemongrass was steam-sprayed five times with 5 × 10−6 M of catechol and PGRs, viz. Indole acetic acid (IAA), kinetin (Kn), 6-benzyl aminopurine (BAP), salicylic acid (SA), triacontanol (TRIA), and ethrel at 90 days after transplantation (DAT). The steam spray was carried out using a calculated distance between the steam source and plant foliage so that the steam jet might not damage the plants. Lemongrass EO was extracted by Clevenger's method and then analyzed using GC-MS. All the parameters were studied at 150 DAT. The steam spray of SA and catechol proved the best for most of the parameters studied. Compared to the control, the application of SA enhanced the plant's fresh and dry weight by 26.1% and 43.4% and the total content of chlorophyll and carotenoids by 52.6% and 62.8% respectively, and chlorophyll fluorescence (Fv/Fm) by 15.2%. Catechol significantly improved the content (350%) and productivity (433.3%) of lemongrass essential oil, but it decreased the proline content (25.0%). SA treatment increased the content of active constituents of EO viz., neral and geranial, by 65.7% and 59.6%, respectively. After SA and catechol, the application of IAA also resulted in promising values for most parameters.

Biotechnology in Future Food Lipids: Opportunities and Challenges.

Lipids are a large group of essential nutrients in daily diets that provide energy and maintain various physiological functions. As the global population is rapidly expanding, there is an urgent need to enhance the production and quality of food lipids. The development of modern biotechnology allows the manipulation of oil production in plants and microorganisms and the improvement of the nutritional value of food lipids. Various metabolic engineering strategies have been exploited to increase oil production and produce value-added oils in traditional oil crops and other novel lipid sources (e.g., plant vegetative tissues, microalgae, and oleaginous microorganisms). Furthermore, natural lipid structures can be modified by lipases to prepare functional lipids, e.g., diacylglycerols, medium-long-medium-type structured triacylglycerols, human milk-fat substitutes, and structuralphospholipids, for specific nutritional demands. In this review, we focus on the recent advances in metabolic engineering of lipid production in plants and microorganisms, and the preparation of functional lipids via biocatalysis.

Biochar related treatments improved physiological performance, growth and productivity of Mentha crispa L. plants under fluoride and cadmium toxicities

Modification of biochar with chemical reagents is an effort to increase the efficiency of this organic material to adsorb environmental pollutants. Typically, these chemically modified materials have special structural specifications that allow the adsorption and stabilization of high levels of environmental pollutants. Therefore, this research was carried out to assess the possible effects of solid and chemically engineered biochars (non-biochar, solid biochar, modified biochar with H2O2, KOH, and H3PO4) on reducing fluoride and cadmium toxicities (non-toxic, 600 mg NaF kg−1 soil, 60 mg Cd kg−1 soil and 600 mg NaF kg−1 soil + 60 mg Cd kg−1) in mint plants (Mentha crispa L.). The application rate of biochar and modified biochars was 25 g kg−1 soil. The addition of biochar and especially engineered biochars to the soil reduced the availability of fluoride and cadmium to the plants. Biochar and chemically modified biochars increased soil cation exchange capacity (CEC) (up to 31%), pH (up to 11%), leaf area (up to 22%), chlorophyll content index (up to 19%), maximum efficiency of photosystem II (up to 32%), biomass (up to 21%) and essential oil production (up to 28%) in mint plants. On the other hand, biochar-related treatments reduced the reactive oxygen species generation, antioxidant enzymes activities, and lipid peroxidation in the root (up to 41%) and leaf tissues (up to 40%). In general, modified biochars showed a better effect than solid biochar in reducing fluoride and cadmium toxicities. The H3PO4-modified biochar was a bit more successful than other biochar-related treatments in increasing mint performance under fluoride and cadmium toxicities. Therefore, the chemically engineered biochars are the superior treatments to improve mint growth and productivity under fluoride and cadmium toxicities, because of their excellent physicochemical specifications such as high level of CEC, functional groups, and specific surface area.

Addition of Arbuscular Mycorrhizal Fungi Enhances Terpene Synthase Expression in Salvia rosmarinus Cultivars

Culinary herbs are commercially cultivated for their wide range of volatile compounds that give characteristic aromas and tastes. Rosemary (Salvia rosmarinus Spenn.) is an excellent model for assessment of methods improvement of volatile production as cultivars offer a wide variety of aromatic profiles due to the large family of terpene synthase genes. Arbuscular mycorrhizal fungi (AMF) associations have been shown to improve essential oil production in aromatic plants and offer one approach to enhance aroma in commercial herb production. Changes in the expression of seven different terpene synthases were compared in six rosemary cultivars in response to addition of AMF to a peat substrate. Addition of AMF profoundly influenced terpene synthase expression in all cultivars and did so without impacting the optimised plant size and uniformity achieved in these conditions. In addition, two methods for AMF application, developed with the horticultural industry in mind, were tested in this study. Uniform incorporation of AMF mixed into the growing substrate prior to planting of a root plug produced the most consistent root colonisation. Overall, our findings demonstrate the potential for the use of AMF in the improvement of aroma in culinary herbs within a commercial setting but show that outcomes are likely to greatly vary depending on variety.

ROLE OF SOME MICRONUTRIENTS IN IMPROVING PRODUCTIVITY AND QUALITY OF SEEDS IN CHIA PLANTS (SALVIA HISPANICA L.) IN SANDY SOIL

L.) is a new crop introduced to the Egyptian agriculture system to enrich it with new species of medicinal plants that have healthy and beneficial ingredients. The purpose of this work was to study the possibility of improvement growth, seed yield, fixed oil production and chemical constituents of chia plants in response to various micronutrients under sandy soil conditions. The field experiment was conducted in the Experimental Farm of EL-Quassassin, Horticulture Research Station, Ismailia Governorate, Egypt. The treatments were (1) control (spray only with tap water), (2) boron (B) at 50 ppm, (3) boron (B) at 100 ppm, (4) iron (Fe) at 100 ppm, (5) iron (Fe) at 200 ppm, (6) zinc (Zn) at 100 ppm, (7) zinc (Zn) at 200 ppm, (8) combination of B (50 ppm) + Fe (100 ppm) + Zn (100 ppm) and (9) combination of B (100 ppm) + Fe (200 ppm) + Zn (200 ppm). In general, the results showed that the growth, seed yield, fixed oil yield, and chemical measurements of chia plant, such as fixed oil composition (fatty acids), photosynthetic pigments content, macro-and micronutrients, total carbohydrates, protein content, total phenols and antioxidant activity of the oil were improved by foliar application of micronutrients solely or in combination compared to control in both seasons. Combination of boron (50 ppm) + iron (100 ppm) + zinc (100 ppm), followed by a combination of B (100 ppm) + Fe (200 ppm) + Zn (200 ppm) led to the highest increases with no significant difference between them in most cases. GC for fixed oil of chia seeds revealed the estimation of seven components

Diacylglycerol Acyltransferase 3(DGAT3) Is Responsible for the Biosynthesis of Unsaturated Fatty Acids in Vegetative Organs of Paeonia rockii.

'Diacylglycerol acyltransferase (DGAT)' acts as a key rate-limiting enzyme that catalyzes the final step of the de novo biosynthesis of triacylglycerol (TAG). The study was to characterize the function of the DGAT3 gene in Paeonia rockii, which is known for its accumulation of high levels of unsaturated fatty acids (UFAs). We identified a DGAT3 gene which encodes a soluble protein that is located within the chloroplasts of P. rockii. Functional complementarity experiments in yeast demonstrated that PrDGAT3 restored TAG synthesis. Linoleic acid (LA, C18:2) and α-linolenic acid (ALA, C18:3) are essential unsaturated fatty acids that cannot be synthesized by the human body. Through the yeast lipotoxicity test, we found that the yeast cell density was largely increased by adding exogenous LA and, especially, ALA to the yeast medium. Further ectopic transient overexpression in Nicotiana benthamiana leaf tissue and stable overexpression in Arabidopsis thaliana indicated that PrDGAT3 significantly enhanced the accumulation of the TAG and UFAs. In contrast, we observed a significant decrease in the total fatty acid content and in several major fatty acids in PrDGAT3-silenced tree peony leaves. Overall, PrDGAT3 is important in catalyzing TAG synthesis, with a substrate preference for UFAs, especially LA and ALA. These results suggest that PrDGAT3 may have practical applications in improving plant lipid nutrition and increasing oil production in plants.

Biological Potential of Alternative Kombucha Beverages Fermented on Essential Oil Distillation By-Products

The complete waste streams (solid waste residue, wastewater, and hydrolate) from the essential oil production of basil, chamomile, lavender, rosemary, and hyssop plants were used as a cultivation media for fermentations of a health-beneficial beverage called kombucha. Considering that these waste streams have not been used as a medium for obtaining kombucha, the main focus of this study was on the biological profiling and sensory analysis of newly-obtained kombucha beverages. According to fermentation parameters and advanced mathematical modelling, it can be concluded that kombucha made from chamomile essential oil by-products achieved the fastest successful kombucha fermentation, with a maximal titratable acidity of 7.2 g/L and a minimal pH value of 2.8. The results of other kombucha fermentations varied between the chosen plant and the waste stream used for beverage production. The obtained phenol and flavonoid contents were in the range of 12.4–56.46 mg GA/100 mL and 0.25–5.07 mg RU/100 mL, respectively. Higher antioxidant capacity as well as anti-inflammatory and antihyperglycemic activities of all kombucha beverages were observed compared to controls. Briefly, achieved DPPH, ABTS, and reducing power values were in the range 30.28–73.70, 192.25–683.29, and 19.37–82.76 mmol TE/100 mL, respectively. According to sensory analysis, the best performance or complete acceptability was noted for kombucha beverages made from lavender and hyssops (in the case of solid waste stream mixed with hydrolate) as well as basil (in the case of concentrated wastewater and hydrolate).

Geographic location and seasonality affect the chemical composition of essential oils of Lippia alba accessions

The chemical composition of essential oils (EO) is determined by genetic factors; however, these factors strongly interact with the environment, leading to significant changes in their constitution. The aim of this study was to evaluate the effect of geographic location on the chemical composition of the EO of seven accessions of Lippia alba (LA-03, LA-13, LA-24, LA-32, LA-36, LA-57, and LA-59) harvested monthly. Trails were conducted simultaneously in São Cristóvão, State of Sergipe, and Uberlândia, State of Minas Gerais, Brazil, from August 2017 to July 2018. The EO obtained by microwave-assisted distillation were analyzed by GC/MS-FID. In cluster analysis, it was observed that for all months, two groups were formed in each location. In Uberlândia, Group 1, with greater abundance of geranial + neral + linalool, included LA-03, LA-24, LA-32, LA-36, and LA-59; and Group 2, with greater abundance of carvone, included LA-13 and LA-57. The same response was observed in São Cristóvão, except for accession LA-24 in August, October, January, February, June, and July, which migrated from Group 1 to Group 2, joining LA-13 and LA-57. There were significant differences in the concentrations of the principal compounds between the locations. Greater concentrations of neral, 1,8-cineole, and ρ-cymene were obtained in accessions LA-03 (38.40%), LA-57 (11.50%), and LA-32 (7.97%), respectively, harvested in Uberlândia. Greater concentrations of carvone (75.66%), linalool (68.19%), geranial (55.90%), limonene (12.18%), piperitone (9.68%), and caryophyllene oxide (6.69%) were obtained in accessions LA-57, LA-24, LA-59, LA-57, LA-13, and LA-59, respectively, harvested in São Cristóvão. There were significant differences in the concentrations of the main compounds, showing that the chemical profiles of the essential oils of L. alba accessions are affected in a quantitative and qualitative way, both between harvests of monthly leaf regrowth in the same geographic region, and in harvests performed in different regions. These data reinforce the need for standardization of essential oil production in native perennial plants, for greater stability of the compounds.

Mathematical Modeling of Heat and Mass Transfer during Moisture–Heat Treatment of Castor Beans to Improve the Quality of Vegetable Oil

An important process in the technology of plant oil production by mechanical pressing is the wet–heat treatment of crushed oilseeds, in which the oilseed (compressed seed) is exposed to saturated vapor and a conductive heat supply. Optimal mode selection of wet–heat treatment based on a detailed study of the physical processes taking place in the compressed seed increases oil release, improves its quality indicators, and decreases energy consumption. Mathematical modeling is an advanced method for studying the dynamics of humidification and frying in the compressed seed. The article introduces a mathematical model and a numerical method for calculating heat-and-mass transformation and phase conversion in the process of the humidification and frying of compressed seeds of the castor plant in a continuous multi-stage heating kettle. This study provides equations for calculating the intensity of phase transformation on the inner and outer surfaces of the wet layer. Data verification indicates the adequacy of the mathematical model, effectiveness of the numerical method, and possibility of their use in optimizing the modes of wet–heat treatment for compressed seed raw material.

An integrated omics analysis reveals the gene expression profiles of maize, castor bean, and rapeseed for seed oil biosynthesis

BackgroundSeed storage lipids are valuable for human diet and for the sustainable development of mankind. In recent decades, many lipid metabolism genes and pathways have been identified, but the molecular mechanisms that underlie differences in seed oil biosynthesis in species with developed embryo and endosperm are not fully understood.ResultsWe performed comparative genome and transcriptome analyses of castor bean and rapeseed, which have high seed oil contents, and maize, which has a low seed oil content. These results revealed the molecular underpinnings of the low seed oil content in maize. First of all, transcriptome analyses showed that more than 61% of the lipid- and carbohydrate-related genes were regulated in castor bean and rapeseed, but only 20.1% of the lipid-related genes and 22.5% of the carbohydrate-related genes were regulated in maize. Then, compared to castor bean and rapeseed, fewer lipid biosynthesis genes but more lipid metabolism genes were regulated in the maize embryo. More importantly, most maize genes encoding lipid-related transcription factors, triacylglycerol (TAG) biosynthetic enzymes, pentose phosphate pathway (PPP) and Calvin Cycle proteins were not regulated during seed oil synthesis, despite the presence of many homologs in the maize genome. Additionally, we observed differential regulation of vital oil biosynthetic enzymes and extremely high expression levels of oil biosynthetic genes in castor bean, which were consistent with the rapid accumulation of oil in castor bean developing seeds.ConclusionsCompared to high-oil seeds (castor bean and rapeseed), less oil biosynthetic genes were regulated during the seed development in low-oil seed (maize). These results shed light on molecular mechanisms of lipid biosynthesis in maize, castor bean, and rapeseed. They can provide information on key target genes that may be useful for future experimental manipulation of oil production in oil plants.

Combined Sulfur and Nitrogen Foliar Application Increases Extra Virgin Olive Oil Quantity without Affecting Its Nutritional Quality

This study investigates the effect of combined sulfur (S) and nitrogen (N) foliar fertilization on leaf S and N concentration, as well as on the growth of olive fruit and on the quantity and quality of olive oil, obtained from two olive cultivars ‘Istarska bjelica’ and ‘Leccino’ in two consecutive years. S and N are some of the most important nutrients, and both play a crucial role in plant oil production. The here-reported fertilization program significantly increased S concentration in leaves without affecting N concentration, which led to an increase in fruit yield and improvement of all fruit morphological parameters. The best oil yield per tree was obtained under the treatment with the highest S/N dose. Oil quality was not affected by S and N supply, and this allowed us to classify all our oil samples as extra virgin (EVOO). Regarding the content of total phenols (TPC) and composition of fatty acid methyl esters (FAME), they remained unaltered under the applied treatments. All investigated fruit morphological parameters, as well as fruit and oil yield, were highly cultivar-dependent. ‘Istarska bjelica’ was characterized as a cultivar with higher fruit mass and pulp percentage, while its stone parameters were lower than those of ‘Leccino’. Consequently, the extraction oil yield obtained from ‘Istarska bjelica’ fruits was much higher. Moreover, environmental conditions had a great impact on fruit and oil quantity. The here-obtained results led us to the conclusion that supply of S and N can enhance oil production without affecting its nutritional quality, a finding that could generate large long-term effects on economic growth in the olive oil sector.

Castor Bean Cake Increases Osmoprotection and Oil Production in Basil Plants Under Saline Stress

Castor Bean Cake Increases Osmoprotection and Oil Production in Basil Plants Under Saline Stress

Sesamum indicum Oleosin L improves oil packaging in Nicotiana benthamiana leaves.

Plant oil production has been increasing continuously in the past decade. There has been significant investment in the production of high biomass plants with elevated oil content. We recently showed that the expression of Arabidopsis thaliana WRI1 and DGAT1 genes increase oil content by up to 15% in leaf dry weight tissue. However, triacylglycerols in leaf tissue are subject to degradation during senescence. In order to better package the oil, we expressed a series of lipid droplet proteins isolated from bacterial and plant sources in Nicotiana benthamiana leaf tissue. We observed further increases in leaf oil content of up to 2.3‐fold when we co‐expressed Sesamum indicum Oleosin L with AtWRI1 and AtDGAT1. Biochemical assays and lipid droplet visualization with confocal microscopy confirmed the increase in oil content and revealed a significant change in the size and abundance of lipid droplets.