Steryl Glycosides Research Articles

Analysis of lipid composition and characterization of acyl steryl glycosides in rose petals by using nontargeted LC/MS

Analysis of lipid composition and characterization of acyl steryl glycosides in rose petals by using nontargeted LC/MS

Regulation of Nanoliposome Rigidity and Bioavailability of Oligomeric Proanthocyanidin with Phytosterols Containing Different C3 Branches.

The rigidity of nanoliposomes significantly influences their physical stability and in vitro and in vivo behaviors (e.g., cellular uptake, blood circulation, biodistribution, etc.). This study aimed to quantify the rigidity of the nanoliposomes composed of phytosterol with varying C3 branches and phospholipids (DPPC, DOPC) using atomic force microscopy. Young's modulus, determined by the Shell model, effectively differentiated between mechanical differences in nanoliposomes with varying components and component structure and phase states. FTIR results indicated that P-SG exhibited the highest Young's modulus (175.98 ± 10.53 MPa) due to the hydrogen bond between the glucose residue of steryl glycosides (SGs) and the phospholipid polar head. However, the rigidity of DOPC nanoliposomes was not significantly different due to the unsaturated bond. The addition of oligomeric proanthocyanidin (OPC) did not change the order of rigidity among the nanoliposomes, with P-SG-OPC having the highest Young's modulus (126.27 ± 2.06 MPa). In the simulated gastrointestinal tract experiment, P-SG-OPC exhibited the greatest stability, with minimal particle aggregation. Cellular uptake experiments revealed that DPPC nanoliposomes with high rigidity had optimal endocytosis, while DOPC nanoliposome uptake was independent of rigidity. In melanin production inhibition tests, the inhibitory effect correlated directly with Young's modulus and P-SG-OPC had the best inhibitory effect on melanin generation. Our findings in this study provide valuable insights into the design and optimization of nanoliposomes for the efficient delivery of active substances, offering potential solutions for improving the efficacy of drug delivery systems.

Increase in steryl glycoside levels and stimulation of lipid raft formation in azuki bean epicotyls under hypergravity conditions

Sterols are the main components of the plasma membrane and are involved in various plant membrane functions. Azuki bean (Vigna angularis (Wild.) Ohwi et Ohashi) seedlings were cultivated under hypergravity conditions, and changes in the levels and composition of membrane sterols in their epicotyls were analyzed. Under hypergravity conditions at 300 g, the levels of steryl glycosides and acyl steryl glycosides per unit length and per gram fresh weight greatly increased, which accounted for an increase in the total sterol levels. Stigmasterol, β-sitosterol, and campesterol were the most abundant sterols. Hypergravity decreased the proportion of stigmasterol but increased that of β-sitosterol. The fatty chains of acyl steryl glycosides mainly consisted of palmitic acid (C16:0), stearic acid (C18:0), linoleic acid (C18:2), and α-linolenic acid (C18:3), and their proportions were not modified under hypergravity conditions. In addition, the density of membrane microdomains, visualized with anti-Flotillin 1 antibody per unit area, increased by hypergravity, suggesting that lipid raft formation was stimulated. These results support the hypothesis that lipid rafts are involved in plant response and resistance to gravity.

Tomato STEROL GLYCOSYLTRANSFERASE 1 silencing unveils a major role of steryl glycosides in plant and fruit development

Free and glycosylated sterols localize in the plant cell plasma membrane, where in combination with other lipids regulate its structure and function. The role of glycosylated sterols in regulating membrane-associated biological processes is more relevant in plants like tomato (Solanum lycopersicum), in which glycosylated sterols are the predominant sterols. A proper ratio of free sterols versus glycosylated sterols has proven to be essential for proper plant performance in several species, but almost nothing is known in tomato. To assess the role of glycosylated sterols in tomato plant and fruit development, we generated transgenic lines of tomato cultivar Micro-Tom expressing two different amiRNAs devised to silence STEROL GLYCOSYLTRANSFERASE 1, the most actively expressed of the four genes encoding sterol glycosyltransferases in this plant. STEROL GLYCOSYLTRANSFERASE 1 gene silencing caused moderate plant dwarfism and reduced fruit size. Analysis of the profile of glycosylated sterols throughout fruit development demonstrated that the maintenance of proper levels of these compounds during the early stages of fruit development is essential for normal fruit growth, since reduced levels of glycosylated sterols trigger a transcriptional downregulatory response that affects genes involved in processes that are critical for proper fruit development, such as seed filling, cell wall extension and auxin signaling.

Phytochemical investigation of unripe banana (Musa AAB) cv. Nendran and its novel ‘Banana Grits’

Novel ‘Banana Grits’ (BG) was prepared from the pulp of unripe banana (Musa AAB) cv. Nendran, and their detailed phytochemical investigation is described. The present work serves as a first report of isolation and identification of glycolipids by exhaustive NMR and HR-ESI-MS analysis from Nendran that include glycolipids viz. monogalactosyldiacylglycerols, digalactosyldiacylglycerols, acyl steryl glycosides, glucocerebrosides, and sterylglycoside. Proximate analysis, estimation of total carotenoid content, and the resistant starch content in BG are also reported. In vitro starch digestion pattern indicated that out of 80% of total starch in BG, 21% is slowly digestible starch (SDS) and 42% is resistant starch (RS). The presence of SDS and RS indicates that they may contribute to gut health and glycaemic control.

Steryl Glycosides in Postfermentation Corn Oil and Its Effect on the Biofuel Production

Post-fermentation corn oil in transesterification process of biodiesel production is considered as feedstock causing major quality problems influencing both filterability and cold flow properties of crude biodiesel. Phytosterols and steryl glycosides (SG) occurring naturally in crude oil in acylated oil-soluble form are transformed during transesterification into unwanted non-acylated SG particles promoting sediments in final FAME (fatty acid methyl ester) product. Elimination and SG precipitates removal is necessary at industrial scale to achieve better biodiesel quality but preferably without significantly increasing costs of biodiesel production. Recombinant steryl glycosidase enzymes represent an environmentally friendly way to reduce SG by its hydrolysis to glucose and sterols – substances with high added value. The production of enzymes directly in the production plant can positively affect the carbon footprint of biotechnological production and increase the efficiency, without high investment costs for conversion or technology change, since the application is possible at any production step with respect to specific enzyme conditions.

Sphingolipid long-chain base hydroxylation influences plant growth and callose deposition in Physcomitrium patens.

Sphingolipids are enriched in microdomains in the plant plasma membrane (PM). Hydroxyl groups in the characteristic long-chain base (LCB) moiety might be essential for the interaction between sphingolipids and sterols during microdomain formation. Investigating LCB hydroxylase mutants in Physcomitrium patens might therefore reveal the role of certain plant sphingolipids in the formation of PM subdomains. Physcomitriumpatens mutants for the LCB C-4 hydroxylase S4H were generated by homologous recombination. Plants were characterised by analysing their sphingolipid and steryl glycoside (SG) profiles and by investigating different gametophyte stages. s4h mutants lost the hydroxyl group at the C-4 position of their LCB moiety. Loss of this hydroxyl group caused global changes in the moss sphingolipidome and in SG composition. Changes in membrane lipid composition may trigger growth defects by interfering with the localisation of membrane-associated proteins that are crucial for growth processes such as signalling receptors or callose-modifying enzymes. Loss of LCB-C4 hydroxylation substantially changes the P.patens sphingolipidome and reveals a key role for S4H during development of nonvascular plants. Physcomitrium patens is a valuable model for studying the diversification of plant sphingolipids. The simple anatomy of P.patens facilitates visualisation of physiological processes in biological membranes.

Structure, metabolism and biological functions of steryl glycosides in mammals.

Steryl glycosides (SGs) are sterols glycosylated at their 3β-hydroxy group. They are widely distributed in plants, algae, and fungi, but are relatively rare in bacteria and animals. Glycosylation of sterols, resulting in important components of the cell membrane SGs, alters their biophysical properties and confers resistance against stress by freezing or heat shock to cells. Besides, many biological functions in animals have been suggested from the observations of SG administration. Recently, cholesteryl glucosides synthesized via the transglycosidation by glucocerebrosidases (GBAs) were found in the central nervous system of animals. Identification of patients with congenital mutations in GBA genes or availability of respective animal models will enable investigation of the function of such endogenously synthesized cholesteryl glycosides by genetic approaches. In addition, mechanisms of the host immune responses against pathogenic bacterial SGs have partially been resolved. This review is focused on the biological functions of SGs in mammals taking into consideration their therapeutic applications in the future.

Characterization and determination of free phytosterols and phytosterol conjugates: The potential phytochemicals to classify different rice bran oil and rice bran

Phytosterols are important beneficial compounds found in rice bran (RB) and rice bran oil (RBO). Although relationships have been confirmed between the forms of phytosterols and their bioactivities, the analysis of different forms of phytosterols in RB and RBO has been lacking. In this study, high temperature gas chromatography-mass spectrometry (HTGC-MS) was combined with the single standard to determine multi-components (SSDMC) method to determine free sterols (FSs) and steryl glycosides (SGs) in RB and RBO. High-performance liquid chromatography (HPLC) was used to determine steryl ferulates (SFs). There was clear variation in the composition of FS, SF and SG, indicating that different forms of phytosterols can discriminate between different RB and RBO. The developed method may be also useful for the detection of other compounds of interest in oils, oil seeds or cereals.

Various adsorbents to improve the filterability of biodiesel

Cold flow properties are the primary drawback to the common usage of biodiesel as an alternative fuel to diesel. Biodiesel's cold flow behaviour is discovered for the main reasons of presence of precipitant or crystal initiate by minor components such as monoglycerides and steryl glycosides. The ASTM test for this precipitant is ‘The Standard Test Method for Determination of Fuel Filter Blocking Potential of Biodiesel (B100) Blend Stock by Cold Soak Filtration Test (CSFT)’. Therefore, in this study, the performance of commercial activated carbon, silica and beach sand as adsorbent is studied in improving the filterability of two different level of refined biodiesel. The adsorbents were used to treat the biodiesel by removing the impurities present in the biodiesel such as the monoglycerides and steryl glycosides compound from biodiesel using adsorption technique. The efficiency of the adsorbent is determined by performing the cold soak filtration test. Based on the cold soak filtration test, precipitate is not visible and the CSTF is within the 360 s limit for the both refined level of biodiesel. However, treatment of these biodiesel with commercial activated carbon, silica and beach sand resulted in further reduce in CSFT. Commercial activated carbon found to be the most effective adsorbent, followed by silica. This is because both adsorbents possessed high surface area of 657.0420 m2/g and 320.2724 m2/g respectively and high pore volume of 0.379097 cm3/g and 0.952320 cm3/g respectively which further enhance its potential as an excellent adsorbent to improve the filterability of biodiesel compared to beach sand which possessed lowest surface area and lowest pore volume of only 1.2630 m2/g and 0.001751 cm3/g respectively.

Industrial applications of selected JFS articles

Industrial applications of selected <i>JFS</i> articles

Transesterification of Refined Bleached Deodorized Palm Oil (RBD PO) Using Homogeneous Base Catalyst and Methanol and Investigation of Factors Filter Blocking Issue in Palm Based Biodiesel

The aim of this study is to investigate the major properties of biodiesel causing filter-blocking issue in biodiesel especially for palm oil based, to identify the suitable solution to reduce or eliminate these factors for improving the filter properties of the palm based biodiesel by control the specific parameter (mono-glycerides during intermediate process and minimize or eliminate the Steryl Glycoside after post treatment. This study may give significant impact especially to local industry of biodiesel producer which operated with normal transesterification process and using palm base feedstock to conform international biodiesel specification such as ASTM D D7501 (Standard Specification for Biodiesel Fuel Blend Stock (B100) for Middle Distillate Fuels). In this paper the Filter Blocking Tendency (FBT) testing and Cold Soak Filterability Test (CSFT) testing procedure and result will be presented.

Steryl Glycosides in Fungal Pathogenesis: An Understudied Immunomodulatory Adjuvant.

Invasive fungal infections pose an increasing threat to human hosts, especially in immunocompromised individuals. In response to the increasing morbidity and mortality of fungal infections, numerous groups have shown great strides in uncovering novel treatment options and potential efficacious vaccine candidates for this increasing threat due to the increase in current antifungal resistance. Steryl glycosides are lipid compounds produced by a wide range of organisms, and are largely understudied in the field of pathogenicity, especially to fungal infections. Published works over the years have shown these compounds positively modulating the host immune response. Recent advances, most notably from our lab, have strongly indicated that steryl glycosides have high efficacy in protecting the host against lethal Cryptococcal infection through acting as an immunoadjuvant. This review will summarize the keystone studies on the role of steryl glycosides in the host immune response, as well as elucidate the remaining unknown characteristics and future perspectives of these compounds for the host–fungal interactions.

Insights Into Oxidized Lipid Modification in Barley Roots as an Adaptation Mechanism to Salinity Stress.

Lipidomics is an emerging technology, which aims at the global characterization and quantification of lipids within biological matrices including biofluids, cells, whole organs and tissues. The changes in individual lipid molecular species in stress treated plant species and different cultivars can indicate the functions of genes affecting lipid metabolism or lipid signaling. Mass spectrometry–based lipid profiling has been used to track the changes of lipid levels and related metabolites in response to salinity stress. We have developed a comprehensive lipidomics platform for the identification and direct qualification and/or quantification of individual lipid species, including oxidized lipids, which enables a more systematic investigation of peroxidation of individual lipid species in barley roots under salinity stress. This new lipidomics approach has improved with an advantage of analyzing the composition of acyl chains at the molecular level, which facilitates to profile precisely the 18:3-containing diacyl-glycerophosphates and allowed individual comparison of lipids across varieties. Our findings revealed a general decrease in most of the galactolipids in plastid membranes, and an increase of glycerophospholipids and acylated steryl glycosides, which indicate that plastidial and extraplastidial membranes in barley roots ubiquitously tend to form a hexagonal II (HII) phase under salinity stress. In addition, salt-tolerant and salt-sensitive cultivars showed contrasting changes in the levels of oxidized membrane lipids. These results support the hypothesis that salt-induced oxidative damage to membrane lipids can be used as an indication of salt stress tolerance in barley.

Pregnenolonyl-α-glucoside exhibits marked anti-cancer and CYP17A1 enzymatic inhibitory activities.

We report here that pregnenolonyl-α-glucoside (2), a steryl glycoside synthesized directly from pregnenolone and glucose via a consecutive multienzyme-catalyzed process, exhibits marked dose-dependent cytotoxic activity against HT29, AGS, and ES-2 cells with IC50 values of 23.5 to 50.9 μM. An in vitro CYP17A1 binding pattern assay and protein-ligand docking model support that 2, like abiraterone, binds in the active site heme iron pocket of CYP17A1.

Extending ‘Granny Smith’ apple superficial scald control following long-term ultra-low oxygen controlled atmosphere storage

Superficial scald is an apple postharvest peel browning disorder that contributes to annual losses of susceptible cultivars, principally where crop protectants that control the disorder are restricted. Controlled atmosphere (CA) storage reduces or eliminates superficial scald while apples remain in storage, especially when pO2 is maintained below 1 kPa. However, symptoms often develop during the post-storage cold chain, which can last beyond a month. Diphenylamine (DPA) or 1-methylcyclopropene (1-MCP) treatment can be used to control scald, but application is required within the first weeks of cold air storage following harvest. After this period, treatments are no longer effective due to irreversible physiological changes, hereby referred to as “scald induction”. As a recent report indicates, apple flesh softening can be reduced by 1-MCP treatment following ultra-low oxygen CA (ULO-CA) storage (pO2 ≤ 1.0 kPa). Here, we sought to determine if ULO-CA would also preserve the capacity to control scald with post-CA treatments. To determine this, ‘Granny Smith’ apples were treated with hot water and 1-MCP at harvest or following long-term (>3 months) in-house and commercial ULO-CA for two consecutive years. Different CA storage environments (2.0 kPa and 1.0 kPa O2) and delays in ULO-CA establishment were used in combinations with delayed DPA and 1-MCP treatments to reveal the scald induction timeline and how different storage practices may impact the effectiveness of post-CA scald control measures. Taken together, results indicate that scald induction is effectively delayed during ULO-CA storage and resumes upon return to air storage. 1-MCP and hot water treatments applied after four months of ULO-CA storage were equally effective at controlling scald during subsequent air storage as treatments applied at harvest. However, the efficacy of post-storage treatments relied on the rapid establishment and maintenance of ULO conditions and immediate treatment upon removal from ULO-CA storage. Scald induction resulted from cumulative oxygen exposure occurring prior to, during (pO2) and following CA storage. Conjugated trienol and acylated steryl glycoside levels at the end of ULO-CA storage reflected how much scald induction had occurred and, likewise, the efficacy of post-storage scald mitigation treatments.

Inactivation of UDP-Glucose Sterol Glucosyltransferases Enhances Arabidopsis Resistance to Botrytis cinerea.

Free and glycosylated sterols are both structural components of the plasma membrane that regulate their biophysical properties and consequently different plasma membrane-associated processes such as plant adaptation to stress or signaling. Several reports relate changes in glycosylated sterols levels with the plant response to abiotic stress, but the information about the role of these compounds in the response to biotic stress is scarce. In this work, we have studied the response to the necrotrophic fungus Botrytis cinerea in an Arabidopsis mutant that is severely impaired in steryl glycosides biosynthesis due to the inactivation of the two sterol glucosyltransferases (UGT80A2 and UGT80B1) reported in this plant. This mutant exhibits enhanced resistance against B. cinerea when compared to wild-type plants, which correlates with increased levels of jasmonic acid (JA) and up-regulation of two marker genes (PDF1.2 and PR4) of the ERF branch of the JA signaling pathway. Upon B. cinerea infection, the ugt80A2;B1 double mutant also accumulates higher levels of camalexin, the major Arabidopsis phytoalexin, than wild-type plants. Camalexin accumulation correlates with enhanced transcript levels of several cytochrome P450 camalexin biosynthetic genes, as well as of their transcriptional regulators WRKY33, ANAC042, and MYB51, suggesting that the Botrytis-induced accumulation of camalexin is coordinately regulated at the transcriptional level. After fungus infection, the expression of genes involved in the indole glucosinolate biosynthesis is also up-regulated at a higher degree in the ugt80A2;B1 mutant than in wild-type plants. Altogether, the results of this study show that glycosylated sterols play an important role in the regulation of Arabidopsis response to B. cinerea infection and suggest that this occurs through signaling pathways involving the canonical stress-hormone JA and the tryptophan-derived secondary metabolites camalexin and possibly also indole glucosinolates.

Lipid Class and Fatty Acid Compositions of Dried Sea Cucumber Apostichopus japonicus

Introduction: Sea cucumber, Apostichopus japonicus, is becoming popular around the world due to its nutritional and medicinal properties. There are still no detailed chemical studies of the lipid class, glycolipids compositions of sea cucumber. Methods: This study was conducted to determine the lipid class and glycolipid compositions of dried sea cucumber, A. japonicus, and analyze fatty acid compositions of Monogalactosyl Diglycerides (MGDG), Steryl Glycosides (SG) and Sulfoquinovosyl Diglycerides (SQDG). Total lipids of sea cucumber were extracted by Bligh and Dyer method and Sep-Pak Silica plus long cartridge, and Thin Layer Chromatography (TLC) silica gel G-60 F254 was used for the separation of different lipid classes and glycolipid compositions. The composition of fatty acids was analyzed by GC. Results &amp; Conclusion: The level of total lipids in the dried sea cucumber, Apostichopus japonicus, was 4 ± 1% of dry weight (w/w) and the amount of neutral lipids, glycolipids and phospholipids was 31 ± 1%, 29 ± 1% and 40 ± 1% of the total lipids (w/w), respectively. MGDG, SG and SQDG were the major glycolipids, and the contents were 37.5 ± 0.3%, 33.8 ± 0.5% and 23.6 ± 0.7% of the total glycolipids (w/w), respectively and significantly higher than other glycolipids (p &lt; 0.05). SQDG contained much higher Arachidonic Acid (AA), Eicosapentaenoic Acid (EPA) and MGDG contained higher Docosahexaenoic Acid (DHA) compared with SG (p &lt; 0.05). Further investigation is required to understand the positional distribution of fatty acids and molecular species in MGDG, SG and SQDG in detail.

Exploiting Lipids to Develop Anticryptococcal Vaccines

Cryptococcus spp. are responsible for life-threatening infections in humans causing mortality rates of 70% in developing countries. Antifungal therapy to combat cryptococcosis is based on the combination of amphotericin B, azoles, and 5-flucytosine. However, treatment failure is frequently triggered by antifungal resistance, drug-drug interactions, and toxicity. New alternatives to prevent cryptococcosis are imperative. Here, we discuss the roles of lipids in the immunological control of the disease caused by Cryptococcus spp. Recently, remarkable advances on immunology of fungal infections have been made and a number of studies indicated the potential of vaccine formulations to combat cryptococcosis. New formulations exploiting virulence regulators and genetically modified attenuated strains have been tested. In this context, lipids have emerged as virulence regulators and immunogens to be explored. Glucosylceramide (GlcCer), sterylglycosides (SGs), and lipid-containing extracellular vesicles have been recently tested in vaccine formulations and their anticryptococcal efficacy was confirmed in vivo. Together, the data discussed here encourage the use of fungal lipids in anticryptococcal vaccinal strategies.

Step-economy synthesis of β-steryl sialosides using a sialyl iodide donor.

Steryl glycosides are prevalent in nature and have unique biological activities dictated by sterol structure, sugar composition, and the stereochemical attachment of the aglycone. A single configurational switch can have profound biological consequences meriting the systematic study of structure and function relationships. Steryl congeners of N-acetyl neuraminic acid (NANA) impact neurobiological processes and may also mediate host/microbe interactions. In order to study these processes, a platform for the synthesis of β-steryl sialosides has been established. Promoter-free glycosidations using a novel α-linked sialyl iodide donor efficiently provide unique amphiphilic sialoglycoconjugates for examining bioactivities in various systems.