Saturated Fatty Alcohols Research Articles

Non-Target Screening of Chemicals in Selected Cotton Products by GC/MS and Their Safety Assessment.

Cotton is used for the production of textiles, hygiene and cosmetic materials. During cultivation and technological processes, various types of substances (surfactants, softeners, lubricants, etc.) penetrate cotton, which can have a harmful effect on both the human body and the environment. The aim of this study was to analyze selected cotton products in order to identify the substances contained and to describe the potential possibilities of inducing textile contact dermatitis (CD). The impact of the identified compounds on the aquatic environment was also taken into account. Nine samples of cotton clothing and seven samples of cotton pads from various manufacturers were tested. Samples after extraction using the FUSLE (Focused Ultrasonic Liquid Extraction) technique were analyzed with GC/MS. Qualitative analysis was based on comparing mass spectra with library spectra using the following mass spectra deconvolution programs: MassHunter (Agilent), AMDIS (NIST), and PARADISE (University of Copenhagen). The parameter confirming the identification of the substance was the retention index. Through the non-target screening process, a total of 36 substances were identified, with an average AMDIS match factor of approximately 900 ("excellent match"). Analyzing the properties of the identified compounds, it can be concluded that most of them have potential properties that can cause CD, also due to the relatively high content in samples. This applies primarily to long-chain alkanes (C25-C31), saturated fatty acids, fatty alcohols (e.g., oleyl alcohol), and fatty acid amides (e.g., oleamide). However, there are not many reports describing cases of cotton CD. Information on the identified groups of compounds may be helpful in the case of unexplained sources of sensitization when the skin comes into contact with cotton materials. Some of the identified compounds are also classified as dangerous for aquatic organisms, especially if they can be released during laundering.

Eryngial: An α,β-Unsaturated Fatty Aldehyde as the Major Phytotoxin in Spiny Coriander (Eryngium foetidum L.) Essential Oil.

Weed species many times possess allelochemicals as a part of their survival strategy. These metabolites can be potential targets in search of natural phytotoxins. This study aims to evaluate the phytotoxic ability of fatty aldehyde-rich essential oil from spiny coriander (Eryngium foetidum) leaves, also known as fitweed or spiritweed and to further identify the active phytotoxins. This oil dose-dependently inhibited the wheatgrass coleoptile and radicle growth in multiple bioassays with half maximal inhibitory concentration (IC50) 30.6-56.7 μg/mL, while exhibiting a less pronounced effect on the germination (IC50 181.8 μg/mL). The phytotoxicity assessment of two oil constituents identified eryngial (trans-2-dodecenal), exclusively major fatty aldehydic constituent as the potent growth inhibitor with IC50 in the range 20.8-36.2 μg/mL during an early phase of wheatgrass emergence. Eryngial-inspired screening of eleven saturated fatty aldehydes and alcohols did not find a significantly higher phytotoxic potency. In an open vessel, eryngial as the supplementation in agar medium, dose-dependently inhibited the growth of pre-germinated seeds of one monocot (bermudagrass) and one dicot (green amaranth) weed species with IC50 in the range 23.8-65.4 μg/mL. The current study identified eryngial, an α,β-unsaturated fatty aldehyde of coriander origin to be a promising phytotoxic candidate for weed control.

First Steps towards Pre-Breeding of Sideritis scardica: A Phenotypic, Agronomic, and Phytochemical Profiling Approach

Sideritis scardica (S. scardica) Griseb., also known as mountain tea, is an important medicinal and aromatic plant species. Due to the high cross-pollination ability of the species, diverse genotypes and phenotypes occur naturally. Considering that superior uniform genotypes are necessary for highly qualitative and sustainable production, this study aimed to conduct a pre-breeding evaluation of three clones (SID1, SID2, and SID3) originating from a selected S. scardica population growing in Greece. According to a phenotypic and agronomic evaluation, SID2 seemed to be superior among the three clones, expressing a good profile with desirable traits (i.e., desired inflorescence length and leaf surface, high length of stems, and high fresh and dry plant biomass). Furthermore, SID3 presented some remarkable measurements regarding morphological (upright growth habit) and agronomic (high number of stems and plant dry weight, desired plant surface) traits. The phytochemical profile of the three clones was assessed with regard to their volatile and polyphenolic compounds. Forty-four constituents were identified in S. scardica essential oil, including hydrocarbon monoterpenes, sesquiterpenoids, oxygenated monoterpenes, and other groups (monoterpene ketones, saturated fatty alcohols, benzoic esters). Liquid chromatographic analysis revealed SID2 as the clone most abundant in the major polyphenolic metabolites: verbascoside (2234.3 mg 100 g−1), isoscutellarein-7-O [6″-O-acetyl]-allosyl(1 → 2) glucoside (1456.5 mg 100 g−1), and 4-methyl hypolaetin-7-O [6″-O-acetyl]-allosyl(1 → 2) glucoside (861.8 mg 100 g−1). The results indicate the ability to combine morphological, agronomic, and phytochemical traits, in order to identify superior S. scardica genotypes for further evaluation and utilization in breeding programs, aiming to create cultivars or varieties for farming purposes with desired performance and high quantitative and qualitative yields.

Therapeutic efficacy of n-Docosanol against velogenic Newcastle disease virus infection in domestic chickens.

The control of Newcastle disease virus (NDV) infection depends solely on vaccination which in most cases is not sufficient to restrain the consequences of such a highly evolving viral disease. Finding out substances for preparing an efficient anti-ND drug would be of high value. n-Docosanol is a saturated fatty alcohol with an inhibitory effect against many enveloped viruses. In this study, we evaluated the therapeutic effect of n-docosanol on NDV infection and shedding in chickens. Chickens infected with a highly virulent NDV were treated with low to high concentrations of n-docosanol (20, 40, and 60 mg/kg body weight) for 4-successive days, once they showed the disease symptoms. Survival and curative rates, virus load, histopathological scoring, and virus shedding were defined. Symptoms development was found to discontinue 24-72 hours post-treatment. Survival rate in the NDV-infected chickens raised 37.4-53.2% after the treatment. n-Docosanol treatment was also found to significantly reduce virus load in the digestive (26.2-33.9%), respiratory (38.3-63%), nervous (26.7-51.1%), and lymphatic (16.4-29.1%) tissues. Histopathological scoring of NDV lesions revealed prominent rescue effects on the histology of different tissues. Importantly, n-docosanol treatment significantly reduced virus shedding in oropharyngeal discharge and feces thereby allowing the restriction of NDV spread. Our findings suggest n-docosanol as a promising remedy in the control strategy of Newcastle disease in the poultry industry.

Chemical characterization of Brazilian propolis using automated direct thermal desorption-gas chromatography-mass spectrometry.

Propolis, produced by honey bees, is used around the world, displaying several corroborated biological activities. Brazil is one of the leading producers of propolis, with a great diversity of types, each with a characteristically chemical fingerprint influenced by the flora of the local region. The secondary metabolite's composition of propolis strongly impacts its biological properties, and its chemical characterization is of great importance for its quality control. Several chromatographic techniques have been applied to characterize propolis, highlighting the extraction of its volatiles and its analysis through gas chromatography. Fourteen Brazilian propolis samples collected in four states, including brown, green and red propolis types, were chemically characterized using the automated direct thermal desorption-gas chromatography-mass spectrometry (DTD-GC-MS). Red propolis type was characterized by acyclic saturated hydrocarbons, fatty alcohols, terpenes, and phenylpropanoids as nonacosane, α-copaene, β-amyrin acetate, anethole, and 7-O-methylvestitol. Brown propolis presented hydrocarbons, monoterpenes, and sesquiterpenes, as α-pinene and α-bisabolol. Brazilian green propolis presented polycyclic aromatic hydrocarbons and sesquiterpenes, including 1-methyl-octahydroanthracene, 2,5-dimethyl-γ-oxo-benzenebutanoic acid, nerolidol, and spathulenol. Principal component analysis (PCA) was performed, allowing for clustering brown and red propolis types, indicating a divergence with the chemical composition of the green propolis samples. The hierarchical cluster analysis (HCA) allowed the chemical fingerprint of each propolis type to be differentiated. Red propolis was characterized by sesquiterpenes, pterocarpans, and isoflavans; brown propolis was characterized by hydrocarbons, aldehydes, and monoterpenes, while green propolis samples were characterized by the presence of polycyclic aromatic hydrocarbons, sesquiterpenes, and naphthalene derivatives. © 2022 Society of Chemical Industry.

Chemical characterization of organic residues on Late Roman amphorae from shipwrecks off the coast of Marsala (Trapani, Italy)

Organic residues were extracted from thirty-three different types of Roman and Late Antique amphorae retrieved from underwater contexts in the custody of the Archaeological Museum “Baglio Anselmi” of Marsala in Sicily. The samples were analysed using GC-MS and 1H NMR, finding biomarkers of plant oils (including saturated and unsaturated fatty acids, alcohols and alkanes present in plant waxes) were identified in seven samples. The biomarkers for Pinaceae spp., used for making pitch, were identified in one sample. The results obtained shed light on the function of different types of North African amphorae, traditionally interpreted as containers for olive oil, wine and fish sauce, presenting new evidence to reassess the system of trade between Sicily and North Africa in Late Antiquity.

Modulating Gut Microbiota: An Emerging Approach in the Prevention and Treatment of Multiple Sclerosis.

Multiple sclerosis (MS) is a progressive neuromuscular disorder characterized by demyelination of neurons of the central nervous system (CNS). The pathogenesis of the disorder is described as an autoimmune attack targeting the myelin sheath of nerve cell axons in the CNS. Available treatments only reduce the risk of relapse, prolonging the remissions of neurological symptoms and halt the progression of the disorder. Among the new ways of targeting neurological disorders, including MS, there is modulation of gut microbiota since the link between gut microbiota has been rethought within the term gut-brain axis. Gut microbiota is known to help the body with essential functions such as vitamin production and positive regulation of immune, inflammatory, and metabolic pathways. High consumption of saturated fatty acids, gluten, salt, alcohol, artificial sweeteners, or antibiotics is the responsible factor for causing gut dysbiosis. The latter can lead to dysregulation of immune and inflammatory pathways, which eventually results in leaky gut syndrome, systemic inflammation, autoimmune reactions, and increased susceptibility to infections. In modern medicine, scientists have mostly focused on the modulation of gut microbiota in the development of novel and effective therapeutic strategies for numerous disorders, with probiotics and prebiotics being the most widely studied in this regard. Several pieces of evidence from preclinical and clinical studies have supported the positive impact of probiotic and/or prebiotic intake on gut microbiota and MS. This review aims to link gut dysbiosis with the development/progression of MS, and the potential of modulation of gut microbiota in the therapeutics of the disease.

Environmentally benign hydrophobic deep eutectic solvents for palladium(II) extraction from hydrochloric acid solution

Hydrophobic deep eutectic solvents (DESs) are considered to be clean and green alternatives to traditional organic solvents for metal ion extraction. Herein, a series of novel hydrophobic DESs were synthesized via the combination of methyltrioctylammonium chloride ([N8881]Cl) as hydrogen bond acceptors (HBAs) and saturated fatty acids or saturated fatty alcohols as hydrogen bond donors (HBDs). Then, the DESs were used for palladium(II) recovery from acid solution. The factors that affect palladium(II) extraction (including the DES species, contact time, DES dose, solution pH, and temperature) were extensively investigated. The DESs exhibit excellent performance for extracting palladium(II) from hydrochloric acid media, and more than 99% of palladium(II) was extracted under optimal conditions. UV–vis, 1H NMR, and FTIR spectral characterizations confirm that the extraction mechanism of palladium(II) involves an anion exchange reaction whereby PdCl42− anions in the aqueous phase replace Cl− anions in DES to form ion-pairs with [N8881+] via electrostatic interactions. Meanwhile, N8881Cl:1-hexanol (1:1) and N8881Cl:hexanoic acid (1:2) exhibit excellent selectivity for palladium(II) over other impurity metal ions. Also, palladium(II) in the loaded DES phase was efficiently recovered as elemental palladium via the hydrazine hydrate reduction method; thus, the DES could be reused for at least 5 cycles.

Lipases of germinating jojoba seeds efficiently hydrolyze triacylglycerols and wax esters and display wax ester-synthesizing activity

BackgroundSimmondsia chinensis (jojoba) is the only plant known to store wax esters instead of triacylglycerols in its seeds. Wax esters are composed of very-long-chain monounsaturated fatty acids and fatty alcohols and constitute up to 60% of the jojoba seed weight. During jojoba germination, the first step of wax ester mobilization is catalyzed by lipases. To date, none of the jojoba lipase-encoding genes have been cloned and characterized. In this study, we monitored mobilization of storage reserves during germination of jojoba seeds and performed detailed characterization of the jojoba lipases using microsomal fractions isolated from germinating seeds.ResultsDuring 26 days of germination, we observed a 60–70% decrease in wax ester content in the seeds, which was accompanied by the reduction of oleosin amounts and increase in glucose content. The activity of jojoba lipases in the seed microsomal fractions increased in the first 50 days of germination. The enzymes showed higher activity towards triacylglycerols than towards wax esters. The maximum lipase activity was observed at 60 °C and pH around 7 for triacylglycerols and 6.5–8 for wax esters. The enzyme efficiently hydrolyzed various wax esters containing saturated and unsaturated acyl and alcohol moieties. We also demonstrated that jojoba lipases possess wax ester-synthesizing activity when free fatty alcohols and different acyl donors, including triacylglycerols and free fatty acids, are used as substrates. For esterification reactions, the enzyme utilized both saturated and unsaturated fatty alcohols, with the preference towards long chain and very long chain compounds.ConclusionsIn in vitro assays, jojoba lipases catalyzed hydrolysis of triacylglycerols and different wax esters in a broad range of temperatures. In addition, the enzymes had the ability to synthesize wax esters in the backward reaction. Our data suggest that jojoba lipases may be more similar to other plant lipases than previously assumed.

GC–MS profiling and in silico prediction of MAPK receptor activation by fatty acids of watercress oil for hair growth marketed in Saudi Arabia

Watercress oil (WCO) is the seed oil of Nasturtium officinale, Brassicaceae family. WCO is a cosmetic for hair growth approved by the Saudi Food and Drug Authority (SFDA). The study aimed to analyze by GC–MS, the phytochemical profile and the safety of WCO as a cosmetic according to SFDA, validates the traditional method of applying hot oil mixtures to the scalp, and also reports the pH, UV absorption, and in-silico binding mechanism of fatty acids for hair growth. The absorption of UV-B light (284.50 nm and 290.60 nm) by WCO suggests that it acts as a sunscreen for the scalp. The pH of the marketed WCO, 5.53 ± 0.02, shall not damage the scalp and hair. The GC–MS analysis confirmed fatty acids as the principal constituents (65.65%) of WCO composed of monounsaturated fatty acids (MUFAs): cis-11-Octadecenoic acid (17.14%), cis-9-Octadecenoic acid (17.11%), cis-13-Eicosenoic acid (11.13%), cis-11-Eicosenoic acid (3.48%), and cis-13-Docosenoic acid (1.64%); saturated fatty acid: n-Hexadecanoic acid (12.89%); saturated fatty alcohol: Docosanol (2.26%). The GC–MS results also confirmed the absence of colorants, toxic solvents, and therapeutic substances in WCO, a cosmetic requirement, according to SFDA. The densities of mixtures of WCO + Coconut oil was 0.801 ± 0.03 mg/mL, and WCO + Olive oil was 0.885 ± 0.01 mg/mL; the kinematic viscosities of WCO + Coconut oil was 21.5 ± 0.0 mm2/s, and WCO + Olive oil was 28.6 ± 0.1 mm2/s at 40℃, which was lesser than the mixtures at 27℃. The decrease in density and viscosity of hot oil mixtures can improve the penetration of oil into the hair filament, which substantiated the traditional application method. In-silico, molecular docking results revealed that all the fatty acid constituents except Docosanol contributed to the hair growth promotion effect by activating MAPK1, MAPK3, and MAPKp38 receptors. This work is the first report on WCO to establish the phytochemical profile to confirm SFDA standard by GC–MS and its in-silico efficiency of activation of MAPK receptors for hair growth.

Production of Long Chain Fatty Alcohols Found in Bumblebee Pheromones by Yarrowia lipolytica.

Fatty alcohols (FA-OH) are aliphatic unbranched primary alcohols with a chain of four or more carbon atoms. Besides potential industrial applications, fatty alcohols have important biological functions as well. In nature, fatty alcohols are produced as a part of a mixture of pheromones in several insect species, such as moths, termites, bees, wasps, etc. In addition, FA-OHs have a potential for agricultural applications, for example, they may be used as a suitable substitute for commercial insecticides. The insecticides have several drawbacks associated with their preparation, and they exert a negative impact on the environment. Currently, pheromone components are prepared mainly through the catalytic hydrogenation of plant oils and petrochemicals, which is an unsustainable, ecologically unfriendly, and highly expensive process. The biotechnological production of the pheromone components using engineered microbial strains and through the expression of the enzymes participating in the biosynthesis of these components is a promising approach that ensures ecological sustenance as well. The present study was aimed at evaluating the production of FA-OHs in the oleaginous yeast, Yarrowia lipolytica, with different lengths of fatty-acyl chains by expressing the fatty acyl-CoA reductase (FAR) BlapFAR4 from B. lapidarius, producing C16:0-OH, C16:1Δ9-OH, and lower quantities of both C14:0-OH and C18:1Δ9-OH, and BlucFAR1 from B. lucorum, producing FA-OHs with a chain length of 18–26 carbon atoms, in this yeast. Among the different novel Y. lipolytica strains used in the present study, the best results were obtained with JMY7086, which carried several lipid metabolism modifications and expressed the BlucFAR1 gene under the control of a strong constitutive promoter 8UAS-pTEF. JMY7086 produced only saturated fatty alcohols with chain lengths from 18 to 24 carbon atoms. The highest titer and accumulation achieved were 166.6 mg/L and 15.6 mg/g DCW of fatty alcohols, respectively. Unlike JMY7086, the BlapFAR4-expressing strain JMY7090 produced only 16 carbon atom-long FA-OHs with a titer of 14.6 mg/L.

Transporting Olive Oil in Roman Times: Chromatographic Analysis of Dressel 20 Amphorae from Pax Julia Civitas, Lusitania

The organic extracts recovered from 14 potsherds of Dressel 20 oil amphorae collected from Pax Julia civitas (Lusitania) were analysed by GC–MS. Biomarkers of plant oils (saturated and unsaturated fatty acids, alcohols and alkanes arising from plant waxes) were identified in ten samples, and Pinaceae spp. pitch biomarkers were also identified in eight samples. The biomarkers identified in the studied Dressel 20 suggest that, even considering re-use, these amphorae should have been used for the same commodity, i.e., storage/transport of a plant oil. The presence of pitch in the amphorae could only be explained if it was used to reduce the porosity of the ceramic paste and minimise the oil diffusion through it.

Preliminary Phytochemical Screening and FTIR Analysis of an Indian Medicinal Herb:<i>Paederia foetida</i> (Prasarini)

Aim: To carry out the preliminary qualitative phytochemical screening of leaf extract of an Indian herb P. foetida and Fourier Transform Infra-red Spectroscopy (FTIR) analysis of the extract containing the highest number of phytochemicals. Method: The leaf extracts were prepared using, water, methanol, ethyl acetate and acetone. Several in vitro phytochemical analyses were carried to check for the presence various secondary metabolites. FTIR analysis of all the 4 extracts were carried out of the for identifying organic secondary metabolites. Results: Ethyl acetate extract was found to be positive for most of the qualitative phytochemical screening test containing almost all the phytochemicals. The FTIR analysis revealed, that the leaf-extracts of P. foetida had phytochemicals of different functional groups such as alkanes, aromatic compounds, aldehydes, saturated fatty acids, alcohols, carboxylic acids, esters, ethers and alkyl halides. Conclusion: The study concluded that, the Indian herb P. foetida is rich secondary metabolites and it can be used in the production alternative and complementary drugs, that can be against various human diseases.

Extractable lipids from Phleum pratense pollen grains and their modifications by ozone exposure

Grass pollen grains are an important source of aeroallergens eliciting respiratory allergic diseases worldwide. In the field of allergology, Phleum pratense pollen is considered as a model for other grass taxa. Upon contact with the aqueous phase of mucosa membranes, lipids are co-delivered from pollen grains with allergens. Lipid molecular species have pro-allergic, pro-inflammatory and immunomodulatory effects on the cells of the allergic immune response. The quantitative analysis of Phleum pratense pollen lipids is missing in the literature. In this work, the total mass of lipids extractable by methylene chloride was determined to be 22 ± 1 µg per mg of Phleum pratense pollen. Eighteen percent of the lipidic mass was quantified and identified by gas chromatographic analysis. Identified lipids included alkanes, alkenes, saturated and unsaturated fatty acids, aldehydes and alcohols. Pollen samples harvested at different times and locations showed a very similar lipidic pattern, both qualitatively and quantitatively. Laboratory ozone exposure of pollen substantially modified its lipidic composition by reactions of ozone with alkenes leading to the production of fatty acids and aldehydes. A deeper knowledge of the lipids released by pollen grains, including pollen from polluted areas, is essential for a better understanding of the chemical environment at the cellular level where allergic reactions take place.

Unhealthy Lifestyle and Nutritional Habits Are Risk Factors for Cardiovascular Diseases Regardless of Professed Religion in University Students.

To date, few studies have evaluated the possible association between religion and nutritional habits, lifestyle and cardiovascular risk in the university population. This study identified differences in the eating habits of Christian and Muslim university students and determined a possible association between the impact of religion on their lifestyles and the parameters related to cardiovascular risk. A cross-sectional study was performed with a sample population of 257 students (22.4 ± 4.76 year) at the campus of the University of Granada in Melilla (Spain). An anthropometric evaluation and a dietary assessment were performed. Blood pressure was also measured. There was a higher prevalence of overweight (29.1%) among Christian university students. The prevalence of pre-hypertension was similar between Christians and Muslims (48.3%) but was higher among Christian males (74.5%). Christian students presented higher levels of visceral fat. Students of both religions ingested carbohydrates, saturated fatty acids and total cholesterol, proteins, sodium and alcohol in excess. Significant positive correlations were found between food energy, sweets, snacks, soft drinks and body mass index (BMI) in both sexes and between the consumption of sausages-fatty meats and the systolic blood pressure (SBP) and body adiposity index (BAI) variables. Muslim students were less likely to consume alcohol (odds ratio [OR] = 7.88, 95% confidence interval [CI] = 4.27, 14.54). Christian and Muslim students presented improvable lifestyles and intake patterns. The high intake of saturated fatty acids, total cholesterol, sodium and alcohol in Christian students could lead to the early development of cardiovascular disease.

Evaluation of Antioxidant Efficiency of Croton tiglium L. Seeds Extracts after Incorporating Silver Nanoparticles

This study aimed to enhance efficiency of the different Croton tiglium (C. tiglium) seeds extracts by incorporation of silver nanoparticles (Ag-NPs) through raised up cytotoxicity against growth of human colon cancer cells. C. tiglium seeds contain various phytoconstituents e.g., carbohydrates (glycosides), flavonoids, sterols (triterpenes), alkaloids and proteins. The protein was hydrolyzed in the dried aqueous seeds extract into free amino acids, the essential amino acids (20.71%) & nonessential amino acids (79.29%). Furthermore, the mucilage in the dried aqueous seeds extract and the total identified sugars represent ~81.21 % of the total mucilage hydrolyzate. The lipoidal contents in the saponifiable matter of the petroleum ether extract, the total saturated fatty acids (13.68%), total monoenoic fatty acids (34.49%), total dienoic fatty acids (45.76%) and total identified fatty acids (93.93%). The unsaponifiable matter was represented by saturated hydrocarbons (40.73%), unsaturated hydrocarbons (18.93%), fatty alcohols (10.08%), sterols (10.61%) and total identified compounds (80.35%). In addition, there were four compounds (β sitosterol, α-amyrin, Oleanolic acid and 3-O-β-D-glucopyranosyl-β-sitosterol (daucosterol)) isolated from the petroleum ether extract. Additionally, incorporation of Ag-NPs into the extract caused no toxicity on the experimental animals when administrated orally. It was found that the median lethal dose (LD50) of the ethanolic, petroleum ether and aqueous seeds extract-Ag nanocomposites was about 7.95, 5.2 and 65 ml/Kg, respectively.

Structure and rheology of oleogels made from rice bran wax and rice bran oil

Structural and rheological properties of oleogels consisting of 0.5–25 wt% rice bran wax (RBX) in rice bran oil (RBO) were explored. RBX was an efficient, thermoreversible oleogelator capable of structuring RBO at concentrations as low as 0.5 wt% RBX. A qualitative temperature-composition phase diagram showed that oleogels containing higher concentrations of RBX were expectedly the most resistant to melting. In oleogels at higher RBX concentrations, polarized light microscopy revealed the presence of a network of interlinked, long aspect ratio wax crystal needles up to 50 μm long. Upon heating, RBX crystals did not undergo any structural transition, based on the constant short spacings at ~ 4.16 and ~ 3.73 Å, indicative of an orthorhombic subcell, and d001 long spacing at 74–76 Å that persisted until RBX fusion. This long spacing was ascribed to the presence of wax esters consisting of long-chain saturated fatty acids (C24 and C22) esterified to C28 – C34 saturated fatty alcohols. During cooling from 90 to 20 °C, the increase in oleogel viscosity resulting from the RBX liquid-solid phase transition was corroborated by DSC-based crystallization onset and enthalpy data. Similarly, elastic moduli and hardness both rose with increasing RBX concentration. This study, which demonstrated that RBX can structure RBO with distinct concentration-dependent properties, serves as the foundation for the development of oleogel-based approaches to saturated and trans fats replacement in processed foods.

Wax synthase MhWS2 from Marinobacter hydrocarbonoclasticus: substrate specificity and biotechnological potential for wax ester production.

Wax synthases are involved in the biosynthesis of wax esters, lipids with great industrial potential. Here, we heterologously expressed the native wax synthase MhWS2 from Marinobacter hydrocarbonoclasticus in Saccharomyces cerevisiae and performed comprehensive analysis of its substrate specificity. The enzyme displayed high wax synthase (but no diacylglycerol acyltransferase) activity both in vivo and in vitro. In the presence of exogenous fatty alcohol, wax esters accounted for more than 57% of total yeast lipids. In vitro, MhWS2 produced wax esters with most of the tested substrates, showing the highest activity with 14:0-, 18:1-, 18:0-, 12:0-, and 16:0-CoA together with saturated C10-C16 fatty alcohols. Co-expression with genes encoding fatty acyl reductases resulted in the accumulation of C26-C36 wax esters. Altogether, our results provide a detailed characterization of MhWS2 which should be useful in the development of strategies for producing wax esters in various expression systems.

Simple lipids and hydrocarbons of New Zealand propolis wax

The composition of neutral lipids of New Zealand propolis wax was determined with the use of Thin Layer Chromatography, Solid Phase Extraction, Gas Chromatography, and Gas Chromatography-Mass Spectrometry. Neutral lipids in the sample were represented mostly by wax esters, long-chain hydrocarbons, and free fatty acids. Low levels of free fatty alcohols were also observed, accompanied by even lower levels of 1-O-alkylglycerols. Wax esters consisted mostly of saturated non-hydroxylated and mono-hydroxylated fatty acids and alcohols, with some monounsaturated non-hydroxylated esters also present. Non-hydroxylated fatty acids contained from 16 to 36 carbon atoms, whilst hydroxylated acids contained from 14 to 26 carbon atoms. While almost 11% of non-hydroxylated fatty acids were monounsaturated, only trace levels of monounsaturated hydroxylated fatty acids were observed. Fatty alcohol moieties of wax esters were predominantly saturated and contained mostly from 24 to 34 carbon atoms per molecule. No polyhydroxylated fatty components were detected in the sample. Overall, the composition of the sample resembled that of beeswax.

Wax Ester Synthase/Diacylglycerol Acyltransferase Isoenzymes Play a Pivotal Role in Wax Ester Biosynthesis in Euglena gracilis

Wax ester fermentation is a unique energy gaining pathway for a unicellular phytoflagellated protozoan, Euglena gracilis, to survive under anaerobiosis. Wax esters produced in E. gracilis are composed of saturated fatty acids and alcohols, which are the major constituents of myristic acid and myristyl alcohol. Thus, wax esters can be promising alternative biofuels. Here, we report the identification and characterization of wax ester synthase/diacylglycerol acyltrasferase (WSD) isoenzymes as the terminal enzymes of wax ester production in E. gracilis. Among six possible Euglena WSD orthologs predicted by BLASTX search, gene expression analysis and in vivo evaluation for enzyme activity with yeast expressing individual recombinant WSDs indicated that two of them (EgWSD2 and EgWSD5) predominantly function as wax ester synthase. Furthermore, experiments with gene silencing demonstrated a pivotal role of both EgWSD2 and EgWSD5 in wax ester synthesis, as evidenced by remarkably reduced wax ester contents in EgWSD2/5-double knockdown E. gracilis cells treated with anaerobic conditions. Interestingly, the decreased ability to produce wax ester did not affect adaptation of E. gracilis to anaerobiosis. Lipid profile analysis suggested allocation of metabolites to other compounds including triacylglycerol instead of wax esters.