Sterol Content Research Articles

Temporal changes of phytoplankton-derived sterols in suspended particulate matter and their implications as biomarkers for phytoplankton abundance in northern Patagonia, Reloncaví Estuarine System (RES), Chile

The Northern Patagonia coast, characterized by an intricate interaction among terrestrial and marine systems such as Reloncaví Estuarine System (RES), present highly productive marine and aquaculture activities, having a significant socio-economic importance in Chile. Understanding the composition of Organic Matter (OM) in aquatic ecosystems is crucial for elucidating biogeochemical processes, and the use of lipid biomarkers, has proven valuable in identifying OM sources. This study investigates the relationship between phytoplankton biomass indicators, including phytoplankton abundance, chlorophyll-a, and sterol molecules synthesized in high percentages by phytoplankton cells, also known as phytoplankton-derived sterols at the RES. The RES encompasses the Reloncaví Fjord (RF) and the Reloncaví Sound (RS) and exhibits a high influenced by oceanic waters and freshwater discharge from rivers Spatio-temporal sampling was conducted during the austral spring, summer and winter expeditions of 2018 and 2019, at two sites in RS and RF mouth (RFm). Our findings reveal higher sterol concentration at RFm than RS. Notably, high sterol concentrations during austral summer season coinciding with increased phytoplankton abundances. Furthermore, higher concentrations of terrestrial-derived sterols such as β-sitosterol (C29Δ5) and stigmasterol (C29Δ5,22), at RFm site suggested an input of OM from the inner RF. Phytoplankton-derived sterols such as 24-methylenecholesterol (C28Δ5,24(28)) provide a reliable estimate of total diatom abundance at both sites (RFm and RS), though they showed a lower relationship with taxonomic subgroups and phytoplankton classes in our study area. Hence, phytoplankton-derived sterols can be considered reliable diatom biomarkers, particularly in the RS, where the primary source of OM is predominantly marine, and even with high sterol degradation values at RES. Our study highlights the importance of interpreting changes in sterol abundances as phytoplankton community shifts. To avoid misinterpretation, it is essential to incorporate direct phytoplankton counts in elucidating the complex biosynthetic sources of sterols within the water column.

Enhancing Antioxidant Activity and Nutritional Profile of Dark Chocolate Through Enrichment with Plant Sterols: A Study on Phytosterol Concentrations and Functional Properties

Chocolate, particularly dark chocolate, is recognized for its antioxidant properties attributed to the presence of flavonoids that promote cardiovascular health. Enriching chocolate with phytosterols, naturally occurring plant compounds known to be effective in reducing cholesterol levels, has the potential to enhance cardiovascular benefits. The incorporation of phytosterols into chocolate provides a palatable and cost-effective means of delivering these beneficial compounds to the body. This study examined the concentrations of sterols and stanols, as well as the antioxidant properties of dark chocolate enriched with plant-derived sterols and stanols. A commercially available preparation containing phytosterol esters (Vegapure® 95 WE) was utilized for this enrichment. Four levels of phytosterol esters (3, 6, 9, and 12%) were added at two distinct stages of chocolate processing: conching and tempering. Sterol and stanol contents were analyzed chromatographically, total phenolic content was determined using the Folin–Ciocalteu method, and antioxidant capacity was assessed via the DPPH assay. Additionally, a sensory evaluation was performed to assess the palatability of the enriched chocolates. The enriched chocolates showed significantly increased levels of sitosterol (up to 1117.68 mg/100 g), campesterol (up to 119.10 mg/100 g), and sitostanol (up to 76.42 mg/100 g). The antioxidant capacity of the enriched dark chocolates was more strongly correlated with phenolic compound content than with phytosterol content. Sensory differences, particularly in taste, were also noted, influenced by the addition of phytosterols. The stage at which phytosterol esters were introduced affected the chocolate’s properties, with the tempering stage proving to be the more advantageous step for incorporating phytosterols, resulting in a lower loss of bioactive compounds. These findings suggest that enriching dark chocolate with phytosterols improves its nutritional profile and functional properties, positioning it as a potential dietary supplement for cholesterol management and cardiovascular health.

Gene-Based Targeting for Treatment of Hypercholesterolemia and Prevention of Atherosclerotic Cardiovascular Disease

Familial hypercholesterolemia, characterized by high levels of LDL cholesterol is a monogenic metabolic disorder linked to atherosclerotic cardiovascular disease. Several genetic mutations in genes such as LDLR and PSK9 are thought to cause familial hypercholesterolemia. This ultimately causes dysfunction of the LDLR pathway, increasing circulating LDL levels. Current treatment revolves around decreasing LDL cholesterol levels in the blood. Statins are the current gold standard while sterol absorption inhibitors (ezetimibe) and PCSK9 inhibitors (evolocumab) are either used as primary treatment in individuals with statin intolerance, or supplementary treatment otherwise. However, CRISPR-Cas9 offers an upstream therapeutic intervention, inducing mutations in pathogenic genes (such as LDLR) to upregulate or downregulate gene expression and subsequently reduce LDL cholesterol levels. This technology thus has great potential as a two-fold treatment option, offering an effective solution for familial hypercholesterolemia, while simultaneously diminishing the risk of atherosclerotic cardiovascular disease. A limitation to current research exists in the sole analysis of monogenic factors in genetic screening, thus polygenic, multifactorial analyses are required to assess more holistic treatment plans. Furthermore, there exist current limitations to CRISPR-Cas9 including ethical limitations and social considerations revolving around the perpetuation of social inequities through technology necessitating future research on global health policies.

Investigation of Phytochemical Composition, Radical Scavenging Potential, Anti-Obesogenic Effects, and Anti-Diabetic Activities of Kaempferia parviflora Rhizomes.

Kaempferia parviflora or commonly known as "Kunyit hitam" by locals, is an edible plant, native to tropical regions, has been extensively utilized for culinary and medicinal applications. The present study aimed to investigate the phytochemical composition and biological activities of the rhizomes of K. parviflora. The ethanol crude and fractionated extracts (hexane and chloroform) of the rhizomes were evaluated for their total phenolic content, total steroidal content, as well as antioxidant, anti-obesogenic, and anti-diabetic activities. The chloroform extract demonstrated the highest concentration of plant sterols (432±0.23 mg BSE/g extract) and a substantial amount of phenolic compounds (1.19×103±0.41 mg GAE/g extract). Gas chromatography-mass spectrometry (GC/MS) analysis revealed that the chloroform extract of the rhizomes is predominantly composed of bioactive flavonoids including tectochrysin (1), 5,7-dimethoxyflavone (2), 3,5,7-trimethoxyflavone (3), 3,4',5,7-tetramethoxyflavone (4), and 4',5,7-trimethoxyflavone (5). Furthermore, the chloroform extract exhibited the highest overall radical scavenging and α-glucosidase inhibitory activities, which can be attributed to the presence of compounds 1-5 in the extract. Collectively, these findings suggest that the chloroform extract of the rhizomes of K. parviflora is a potentially valuable source of bioactive compounds with antioxidant, anti-obesogenic, and anti-diabetic properties, with potential application in therapeutics and functional foods.

Impact of ERG6 Gene Deletion on Membrane Composition and Properties in the Pathogenic Yeast Candida glabrata.

The ERG6 gene is crucial for the biosynthesis of ergosterol, a key component of yeast cell membranes. Our study examines the impact of ERG6 gene deletion on the membrane composition and physicochemical properties of the pathogenic yeast Candida glabrata. Specifically, we investigated changes in selected sterol content, phospholipid composition, transmembrane potential, and PDR16 gene activity. Sterol levels were measured using high-performance liquid chromatography, the phospholipid profile was analysed via thin-layer chromatography, transmembrane potential was assessed with fluorescence spectroscopy, and gene expression levels were determined by quantitative PCR. Our findings revealed a depletion of ergosterol, increased zymosterol and eburicol content, an increased phosphatidylcholine and a reduced phosphatidylethanolamine content in the Δerg6 strain compared to the wt. Additionally, the Δerg6 strain exhibited membrane hyperpolarization without changes in PDR16 expression. Furthermore, the Δerg6 strain showed increased sensitivity to the antifungals myriocin and aureobasidine A. These results suggest that ERG6 gene deletion leads to significant alterations in membrane composition and may activates an alternative ergosterol synthesis pathway in the C. glabrata Δerg6 deletion mutant.

A receptor kinase senses sterol by coupling with elicitins in auxotrophic Phytophthora

Sterols are vital nutrients and signals for eukaryotic organisms. Mammalian cells are known to sense and respond to sterol status changes to maintain them within strict limits, a process associated with various human diseases. However, this process is not understood in oomycete pathogens, most of which are sterol auxotrophic and must obtain sterols from host plants. Here, we report that Phytophthora sojae SSRK1 (sterol-sensing receptor kinase 1) detects host sterols by coupling with elicitins, thereby controlling signaling and sterol absorption. Sterols are recruited by extracellular soluble elicitins, and these complexes then bind to SSRK1 to form trimolecular complexes. These complexes subsequently trigger downstream calcium influx, activation of mitogen-activated protein kinase, and transcriptome reprogramming through the receptor's kinase activity. Our data demonstrate a unique sterol sensing pathway where elicitins and a transmembrane receptor kinase SSRK1 act as coreceptors for extracellular sterols. These findings also portray a sterol-based war between oomycetes and plants, providing a unique perspective on how a pathogen detects host signals during infection.

Virgin Olive oil Authenticity Assays in a Single Run Using Two-Dimensional Liquid Chromatography-High Resolution Mass Spectrometry.

Sterols and triterpenic alcohol analyses are one of the officially established parameters for assessing the authenticity of virgin olive oil (VOO). Most of the applications described for sterol analysis, including the official method, only allow the determination of the total sterol content but not its distribution in free or esterified form. This work proposes a two-dimensional liquid chromatography/high-resolution mass spectrometry (2D-LC-HRMS) method for the simultaneous analysis of triterpenic alcohols, free sterols and steryl esters. A reversed phase liquid chromatography (RPLC)-RPLC coupling was performed through a multiple heart-cutting interface equipped with an active solvent modulation (ASM) valve. Additionally, a selection valve was coupled to the 2D-LC system, allowing the simultaneous data acquisition from both dimensions in a single analysis. A simplified sample treatment based on solid phase extraction was also proposed to avoid tedious steps such as saponification or derivatization before gas chromatography analysis. To evaluate the content of these compounds in different olive oil categories, the proposed 2D-LC-HRMS system was applied to a set of samples from different commercial olive oil categories (extra virgin olive oil, virgin olive oil, olive oil, pomace olive oil) and sunflower oil. The results revealed significant differences in the distribution of free and esterified sterols of the analyzed samples, highlighting the free/esterified sterol ratio as a powerful tool to unveil olive oil fraud practices and fat manipulation.

Dysbiosis index and fecal concentrations of sterols, long-chain fatty acids and unconjugated bile acids in dogs with inflammatory protein-losing enteropathy.

Canine protein-losing enteropathy (PLE) is a syndrome characterized by gastrointestinal loss of proteins. While fecal microbiome and metabolome perturbations have been reported in dogs with chronic enteropathy, they have not been widely studied in dogs with PLE. Therefore, the study aims were to investigate gut microbiome and targeted fecal metabolites in dogs with inflammatory PLE (iPLE) and evaluate whether treatment affects these changes at short-term follow-up. Thirty-eight dogs with PLE and histopathological evidence of gastrointestinal inflammation and 47 healthy dogs were enrolled. Fecal samples were collected before endoscopy (T0) and after one month of therapy (T1). Microbiome and metabolome alterations were investigated using qPCR assays (dysbiosis index, DI) and gas chromatography/mass spectrometry (long-chain fatty acids, sterols, unconjugated bile acids), respectively. Median (min-max) DI of iPLE dogs was 0.4 (-5.9 to 7.7) and was significantly higher (p < 0.0001) than median DI in healthy dogs [-2.0 (-6.0 to 5.3)]. No significant associations were found between DI and selected clinicopathological variables. DI did not significantly differ between T0 and T1. In iPLE dogs, at T0, myristic, palmitic, linoleic, oleic, cis-vaccenic, stearic, arachidonic, gondoic, docosanoic, erucic, and nervonic acids were significantly higher (p < 0.0001) than healthy dogs. In iPLE dogs, oleic acid (p = 0.044), stearic acid (p = 0.013), erucic acid (p = 0.018) and nervonic acid (p = 0.002) were significantly decreased at T1. At T0, cholesterol and lathosterol (p < 0.0001) were significantly higher in iPLE dogs compared to healthy dogs, while total measured phytosterols were significantly lower (p = 0.001). No significant differences in total sterols, total phytosterols and total zoosterols content were found at T1, compared to T0. At T0, total primary bile acids and total secondary bile acids did not significantly differ between healthy control dogs and iPLE dogs. No significant differences in fecal bile acid content were found at T1. Dysbiosis and lipid metabolism perturbations were observed in dogs with iPLE. Different therapeutic protocols lead to an improvement of some but not all metabolome perturbations at short-term follow-up.

Phytosterol Depletion in Soybean Oil Using a Synthetic Silica Adsorbent

Phytosterols in vegetable oils have gained attention for their nutritional benefits in foods and food supplements. However, the use of vegetable oils in emulsions for infant formulas and parenteral nutrition has raised some concerns, as phytosterols may contribute to phytosterolemia in the case of infant formulas and, in a second scenario, to parenteral nutrition-associated liver disease. The present study proposes removing phytosterols from soybean oil using a synthetic amorphous silica Trisyl® (E551) as an adsorbent material. The process is simple and involves stirring the oil at a high temperature under vacuum conditions followed by filtration to remove the adsorbent. A rotational factorial design of experiments, considering the adsorbent/oil ratio, temperature, and time was carried out to determine the optimal conditions. Additionally, the effects on tocopherols levels and formation of trans fatty acids were explored. The total sterol content in the initial refined soybean oil was 2540 mg/kg, with 32% in ester form (813 mg/kg). The treatments effectively reduced the sterol concentration, achieving a reduction of nearly 70% when 10% Trisyl®, 140 °C, and a 90-min treatment were applied. Under these conditions, nearly 80% of the oil was recovered. Campesterol and stigmasterol levels were almost halved. Tocopherol losses were found to be below 20%. Thermal degradation, as analyzed by triacylglycerol polymers and trans fatty acids, was not observed in the treatments.

Identification of a homozygous variant in ABCG5 by panel sequencing in a Pakistani family with sitosterolemia: Genotype-phenotype correlation and management considerations

Sitosterolemia is a rare autosomal recessive disorder characterized by impaired excretion of plant sterols, leading to their accumulation in tissues and organs. We identified a hitherto unreported homozygous variant, in ATP-binding cassette sub-family G member 5 (ABCG5) (NM_022436.3) c.274A>G p.(Lys92Glu), segregating in two affected sibs (Sit1C and Sit1F) of a consanguineous Pakistani family, during genetic workup for hereditary hemolytic anemia. Both patients had anemia, history of gum bleed and easy bruising. Peripheral film revealed stomatocytes and macrothrombocytopenia. Plasma sitosterol level was found to be significantly high (27.7 mg/dL and 25.1 mg/dL for Sit1C and F respectively), confirming diagnosis of sitosterolemia in both patients. Treatment with Ezetimibe, a sterol absorption inhibitor, resulted in significant decrease in sitosterol as well as LDL-cholesterol, in these patients. This study confirms the potential of panel sequencing as a diagnostic tool for sitosterolemia. Definitive diagnosis has significant clinical implications for genetic counseling and management strategies, such as dietary modifications and successful management with Ezetimibe.

How relevant are sterols in the mode of action of prymnesins?

Prymnesins, produced by the haptophyte Prymnesium parvum, are considered responsible for fish kills when this species blooms. Although their toxic mechanism is not fully understood, membrane disruptive properties have been ascribed to A-type prymnesins. Currently it is suggested that pore-formation is the underlying cause of cell disruption. Here the hypothesis that A-, B-, and C-type prymnesins interact with sterols in order to create pores was tested. Prymnesin mixtures containing various analogs of the same type were applied in hemolysis and cytotoxicity assays using Atlantic salmon Salmo salar erythrocytes or rainbow trout RTgill-W1 cells. The hemolytic potency of the prymnesin types reflected their cytotoxic potential, with approximate concentrations reaching 50 % hemolysis (HC50) of 4 nM (A-type), 54 nM (C-type), and 600 nM (B-type). Variabilities in prymnesin profiles were shown to influence potency. Prymnesin-A (3 Cl) + 2 pentose + hexose was likely responsible for the strong toxicity of A-type samples. Co-incubation with cholesterol and epi-cholesterol pre-hemolysis reduced the potential by about 50 % irrespective of sterol concentration, suggesting interactions with sterols. However, this effect was not observed in RTgill-W1 toxicity. Treatment of RTgill-W1 cells with 10 µM lovastatin or 10 µM methyl-β-cyclodextrin-cholesterol modified cholesterol levels by 20-30 %. Regardless, prymnesin cytotoxicity remained unaltered in the modified cells. SPR data showed that B-type prymnesins likely bound with a single exponential decay while A-types seemed to have a more complex binding. Overall, interaction with cholesterol appeared to play only a partial role in the cytotoxic mechanism of pore-formation. It is suggested that prymnesins initially interact with cholesterol and stabilize pores through a subsequent, still unknown mechanism possibly including other membrane lipids or proteins.

Antioxidant activity, physico-chemical properties, and bioactive compounds of Nigella sativa seeds and oil impacted by microwave processing technique

Strongly anti-oxidant and medicinal, Nigella sativa L (NS) is utilized in conventional medicine to address a range of illnesses, including gastrointestinal, inflammatory and rheumatic illnesses. This study was carried out to investigate the effects of microwave processing on the physico-chemical properties of Moroccan-grown Nigella sativa seeds and oils, as well as to investigate the antioxidant qualities of black cumin oils under conditions of accelerated oxidation. The study's specific goal was to ascertain the effects of varying microwave power levels (500 and 750 W) and roasting times (5, 10, and 15 min) on the black cumin oils' quality indices, fatty acid and sterol content, carotenoid and chlorophyll levels, mineral profile, tocopherol amount, and overall antioxidant activity. To this end, the seeds of black cumin were roasted at two power levels (500 and 750 W) and for three different periods (5, 10, and 15 min) in a microwave oven. The obtained results show that the duration and the processing power did not significantly influence the amount of sterols and fatty acids. In contrast, the quality indices, physico-chemical properties, carotenoid and chlorophyll contents, mineral profile, and tocopherol amount were influenced by the microwave processing. A significant decline in the antioxidant activity was recorded from 45.01 ± 0.81 % (unroasted cumin seeds) to 4.32 ± 0.91 % (750 W/5 min). Based on these findings, the black cumin oil preparations should be handled carefully and the oil must be protected once extracted. The stability and preservation of antioxidants are crucial steps against pro-oxidant and inflammatory conditions that could favour cellular senescence and accelerate aging processes.

Effect of Andean Lupin (Lupinus mutabilis) genotype and harvest altitude on the chemical composition and nutritional quality of flours

Andean Lupin (Lupinus mutabilis S.) or tarwi, a legume cultivated in the Andean region of South America, is considered a protein source. In this work, flours were prepared from different Andean Lupin genotypes, namely Cholo Fuerte (CHF), Común (CM), or Altagracia (ALT), grown at 2700 (1) or 3300 (2) meters above sea level. The effect of genotype and growth altitude on the chemical composition, color, phytochemical (alkaloids, free phenolics, fatty acids, and sterols) content, antioxidant activity, and microbiological quality of the flours was evaluated. CM-1 flour had higher protein, polyunsaturated fatty acid (PUFA), and Δ5-avenasterol content. CHF-1 flour had higher crude fiber, Δ7-campesterol, clerosterol, and saturated fatty acid (SFA) content and higher antioxidant activity. ALT-2 flour had the highest total sterol content, particularly stigmasterol and β-sitosterol. None of the flours contained alkaloids or microorganisms, confirming that the preparation process was efficient. Andean Lupin cultivated at high and low altitude provides flour with high phytosterol and PUFA content, respectively. CM-1 flour has potential use in the food and nutraceutical industry due to its higher protein, essential fatty acid or PUFA, and total sterol content as well as low SFA content.

Micro-scale quantitative analysis of sterol content in liposomes

The high complexity of biological membranes has driven the development and application of a wide range of model membrane systems. Among these models, liposomes are extensively used because of their versatility in mimicking cellular membranes with a wide range of lipid compositions. However, the accurate quantification of lipid components, such as sterols, within these models remains a critical requirement for validation, data interpretation, and comparison. Here, we present a reliable and sensitive colorimetric assay using the Zak color reaction, which we have specifically adapted for the quantification of sterols at the micro-scale level. The assay was evaluated using cholesterol, ergosterol, and sitosterol standards, reflecting the diversity of sterol species across organisms. The reaction mechanism involves the dehydration of sterols to form carbonium ions, which are oxidized to form various enylic carbonium ions with specific absorption peaks. Due to the different chemical structures of cholesterol, ergosterol, and sitosterol, the resulting spectra show that the colored reaction products are formed in different proportions. The stability and interconversion of these species over time were analyzed. Cholesterol and sitosterol showed a clear peak at 555 nm, while ergosterol had prominent peaks at shorter wavelengths. Sterol assays on liposomal preparations showed accurate sterol incorporation with minimal loss during processing steps. These results demonstrate that this assay provides a robust and accurate measurement of sterol content in large unilamellar vesicles, making it a valuable tool for liposomal studies.

Integrating QTL mapping and transcriptomics to decipher the genetic architecture of sterol metabolism in Brassica napus L.

Sterols are secondary metabolites commonly found in rapeseed that play crucial physiological roles in plants and also benefit human health. Consequently, unraveling the genetic basis of sterol synthesis in rapeseed is highly important. In this study, 21 individual sterols as well as total sterol (TS) content were detected in a double haploid (DH) population of Brassica napus, and a total of 24 quantitative trait loci (QTL) and 157 mQTL were identified that were associated with TS and different individual sterols. Time-series transcriptomic analysis showed that the differentially expressed genes (DEGs) involved in sterol and lipid biosynthesis pathways were enriched. Additionally, a regulatory network between sterol-related DEGs and transcription factors (TFs) was established using coexpression analysis. Some candidate genes were identified with the integration of transcriptomic analysis and QTL mapping, and the key candidate gene BnSQS1.C03 was selected for further functional analysis. BnSQS1.C03 demonstrated squalene synthase activity in vitro and increased the TS by 3.8% when overexpressed in Arabidopsis. The present results provide new insights into sterol regulatory pathways and a valuable genetic basis for breeding rapeseed varieties with high sterol content in the future.

Effect of Pulsed Electric Field Pretreatment on the Concentration of Lipophilic and Hydrophilic Compounds in Cold-Pressed Grape Seed Oil Produced from Wine Waste.

Pretreatment of grape pomace seeds with a pulsed electric field (PEF) was applied to improve the extraction yield of cold-pressed grape seed oil. The effects of different PEF conditions, electric field intensities (12.5, 14.0 and 15.6 kV/cm), and durations (15 and 30 min) on the oil chemical composition were also studied. All PEF pretreatments significantly increased the oil yield, flow rate and concentration of total sterols (p < 0.05). In addition, similar trends were observed for total tocochromanols and phenolic compounds, except for PEF pretreatment under the mildest conditions (12.5 kV/cm, 15 min) (p < 0.05). Notably, the application of 15.6 kV/cm for 30 min resulted in the highest relative increase in oil yield and flow rate (29.6% and 56.5%, respectively) and in the concentrations of total tocochromanols, nonflavonoids, and flavonoids (22.1%, 60.2% and 81.5%, respectively). In addition, the highest relative increase in the concentration of total sterols (25.4%) was achieved by applying 12.5 kV/cm for 30 min. The fatty acid composition of the grape seed oil remained largely unaffected by the PEF pretreatments. These results show that PEF pretreatment effectively improves both the yield and the bioactive properties of cold-pressed grape seed oil.

Bioactive Compounds in the Oils of the Autochthonous Slovenian Olive Varieties 'Buga', 'Črnica' and 'Drobnica'.

The adaptation of autochthonous olive varieties to local soil and climatic conditions can lead to a unique chemical composition and characteristics of olive oils that may differ from the generally accepted quality standards set out in the International Olive Oil Council strategy documents and EU regulations. Therefore, the fatty acid composition, biophenol, tocopherol, sterol and triterpenic dialcohol content and composition of the autochthonous Slovenian olive varieties 'Buga', 'Črnica' and 'Drobnica' were studied for a three-year period with the aim of valorising the characteristics of the three olive varieties. Standardised and accredited analytical methods in accordance with SIST EN ISO/IEC 17025:2017 were applied. The results of the investigation showed that the highest average amount of oleic acid (75.75%) was found in the oils of the 'Črnica' variety, followed by the 'Drobnica' (72.06%) and the 'Buga' (68.73%). All three varieties are a good source of total biophenols ('Buga' 616 mg/kg, 'Drobnica' 569 mg/kg and 'Črnica' 427 mg/kg) and α-tocopherol ('Buga' 378 mg/kg, 'Drobnica' 279 mg/kg, and 'Črnica' 243 mg/kg). 'Buga' and 'Drobnica' are characterised by high amounts of total sterols, 2468 mg/kg and 2391 mg/kg, respectively, while 'Črnica' oils, in comparison, showed a lower average value of total sterols (1351 mg/kg). Due to their exceptional chemical composition, 'Buga', 'Črnica' and 'Drobnica' show great potential for the further cultivation and valorisation of traditional olive oil production in the region, thus contributing to the preservation of biodiversity and local traditions. The quality parameters of olive oil from the autochthonous Slovenian olive varieties 'Buga', 'Črnica' and 'Drobnica' also fulfil the limits for extra virgin olive oil according to the Commission Delegated Regulation (EU) 2022/2104, despite local climatic influences. However, accelerated growth due to climatic changes affecting early harvest can lead to them falling outside these limits, which was observed in particular for the 'Buga' variety in terms of the linoleic acid content. This study emphasises the importance of timing the harvest to achieve optimum maturity and meet EU quality standards, taking into account the genetic makeup of the varieties and their response to the current climatic conditions.

Unique formulation of edible blended oil from sesame and mustard seeds grown in Bangladesh

Edible oils are vulnerable to oxidation-induced degradation, leading to off-flavors, carcinogenic products, and reduced nutritional content. This work aimed to prepare a blended oil (BO) from indigenous mustard and sesame seeds to extend the oil’s shelf life and boost its nutritional value. Four blends were formulated with sesame oil (SO) and mustard oil (MO) in the ratios of SO50:MO50, SO60:MO40, SO70:MO30 and SO80:MO20. GCMS analyses showed that the SO80:MO20 blend had an erucic acid content of 4.22 %, which is below the internationally accepted limit of 5 %, and an ideal fatty acid ratio of 1:1.3:1; saturated fatty acid (SFA): monounsaturated fatty acid (MUFA): polyunsaturated fatty acid (PUFA), close to the WHO/FAO permissible limit. The blend SO80:MO20 was then assessed and related to single oil. The physicochemical properties of the blended oil were superior to those of the individual oils. BO exhibited higher levels of lignan (48.96 %) and tocopherol (13.58 %) than SO (48.89 % and 12.74 %) and MO (0.24 % and 6.22 %). Additionally, BO’s sterol content was 18.7 %, surpassing SO’s 14.7 % but falling short of MO’s 21.13 %. Moreover, BO’s flash point (318 °C) closely resembled that of SO (320 °C) and MO (316 °C). Aflatoxin and trace metal levels were detected and found to be well below than permitted ranges. The blend had a total antioxidantcapacity of 95 % with an IC50 value of 0.575 mg/mL, which was higher than that of the individual oils andcomparable to standards. Over 180 days of storage at room temperature, the moisture content, refractive index, free fatty acids, peroxide value, p-anisidine value, saponification value, iodine value, and totox value of the BO showed a slower increase compared to the individual oils. The estimated fatty acid ratio and enriched antioxidant in the blended oil enhanced its stability and nutritional potency over the individual oils. The results of this work may represent Bangladesh’s first unique oil blend composition.

Comprehensive Modulation of Secondary Metabolites in Terpenoid-Accumulating Mentha spicata L. via UV Radiation.

In plants, secondary metabolites change in response to environmental conditions. These changes co-regulate resilience to stressful environmental conditions, plant growth and development, and interactions between plants and the wider ecosystem, while also affecting soil carbon storage and atmospheric and climatic conditions. The objective of this study was to determine the association between UV exposure and the contents of key metabolites, including amino acids, phenolics, flavonoids, terpenoids, carotenoids, tocopherols, and phytosterols. Mentha spicata plantlets were grown in tissue culture boxes for 30 days and then exposed to a low dose of broadband UV-B (291-315 nm; 2.8 kJm-2 biologically effective UV) enriched light for eight days. Metabolite contents were quantified either immediately after the final UV exposure, or after seven days of recovery under photosynthetically active radiation. It was found that UV promoted the production of flavonoids (1.8-fold) ahead of phenolic acids (unchanged). Furthermore, the majority of monoterpenes and sesquiterpenes, constituents of valuable mint essential oil, were significantly increased through UV treatment (up to 90-fold for α-linalool). In contrast, the contents of carotenoids and tocopherols did not increase following UV exposure. A comparison between plants sampled immediately after UV exposure and after seven days of recovery showed that there was an overall increase in the content of carotenoids, mono- and sesquiterpenes, phenolics, and amino acids following recovery, while the contents of sterols and tocopherols decreased. These UV-induced changes in metabolite profile may have important consequences for agriculture, ecology, and even the global climate, and they also provide an exciting opportunity to enhance crop value, facilitating the development of improved products with higher levels of essential oils and added benefits of enhanced flavour, colour, and bioactive content.

Genotype by environment interaction influence on functional molecules (tocopherols and sterols) accumulation in sunflower oil

Tocopherol and sterol are non-dietary functional molecules in sunflower oil, which act as antioxidants, reduce cholesterol and improve immunity against diseases. The present study was designed to determine tocopherol and sterol contents in 13 high and two low oleic acid sunflower hybrids across two seasons (spring and autumn) and four locations under subtropical conditions of Pakistan with contrasting reproductive phase temperatures. The results showed that tocopherol and sterol contents varied across the seasons and locations. Autumn planting produced high tocopherol content. Moreover, locations under high temperature during reproductive phase negatively affected the sterol and tocopherol contents. High oleic acid hybrids yielded 38% higher tocopherol content than low oleic acid hybrids. High oleic acid hybrids produced higher sterol contents at all locations and seasons. Hybrids such as H4 and H5 are considered stable due to comparatively close values of tocopherol and sterol contents across the four locations when compared with standard checks and other hybrids during spring season as indicated from various stability parameters. Hybrids H8, H4 and H5 also manifested higher magnitude of heterosis for tocopherol and sterol contents that may be due to overdominance gene action. Breeding lines such as B.116.P, B.112.P and RH.365 were positive combiners for the investigated traits, thus likely carrying positive alleles for both tocopherol and sterol traits.