Human Oral Phase Coupled with In Vitro Dynamic Gastrointestinal Digestion for Assessment of Plant Sterol Bioaccessibility from Wholemeal Rye Bread.

A dynamic gastrointestinal digestion system (simgi) after a human oral phase was used, for the first time, to assess the bioaccessibility of plant sterols (PS) from wholemeal rye bread (74.8 ± 2.2 mg of PS/100 g d.m.) and PS-enriched wholemeal rye bread (PS-WRB) (1.6 ± 0.04 g of PS/100 g of fresh bread). The use of these solid food matrices requires a novel adaptation of the gastric phase of the system. The PS identified in the breads are campesterol, campestanol, stigmasterol, ß-sitosterol, sitostanol, Δ5-avenasterol, Δ5,24-stigmastadienol, Δ7-stigmastenol, and Δ7-avenasterol. The bioaccessibility of the total PS, only quantifiable in PS-WRB, is 19.9%, with Δ7-avenasterol being the most bioaccessible and Δ5-avenasterol being the least (p < 0.05). As shown in this study, PS-WRB can be considered to be a good choice to include in the daily diet. Furthermore, although the use of dynamic digestion methods for evaluating bioaccessibility implies high costs and technical complexity, their application means a closer approximation to in vivo scenarios.

Phytosterols: Physiological Functions and Potential Application.

Dietary intake of natural substances to regulate physiological functions is currently regarded as a potential way of promoting health. As one of the recommended dietary ingredients, phytosterols that are natural bioactive compounds distributed in plants have received increasing attention for their health effects. Phytosterols have attracted great attention from scientists because of many physiological functions, for example, cholesterol-lowering, anticancer, anti-inflammatory, and immunomodulatory effects. In addition, the physiological functions of phytosterols, the purification, structure analysis, synthesis, and food application of phytosterols have been widely studied. Nowadays, many bioactivities of phytosterols have been assessed in vivo and in vitro. However, the mechanisms of their pharmacological activities are not yet fully understood, and in-depth investigation of the relationship between structure and function is crucial. Therefore, a contemporaneous overview of the extraction, beneficial properties, and the mechanisms, as well as the current states of phytosterol application, in the food field of phytosterols is provided in this review.

Biosynthesis of the triterpenoid withanolides in Withaniasomnifera.

Ashwagandha (Withania somnifera L. Dunal) is a versatile medicinal plant of Solanaceae family, renowned for its potent therapeutic properties, due to which it is extensively used in Indian traditional systems of medicine such as Ayurveda. The medicinal properties are attributed to specialized metabolites known as withanolides, which are chemically triterpenoid steroidal lactones. Despite their significance, the biosynthetic pathway of withanolides remains poorly understood. It is hypothesized that withanolides are synthesized through the universal sterol pathway, wherein sterol precursors undergo various biochemical modifications such as hydroxylation, oxidation, cyclization, and glycosylation, yielding a diverse array of downstream withanolides and withanosides. Consequently, comprehending the biosynthetic pathway of withanolides is crucial to facilitate advancements in withanolides productivity through metabolic engineering or synthetic biology approaches. This article aims to provide an update on the efforts made toward understanding withanolides formation and regulation and highlights gaps and approaches to elucidate the withanolides biosynthesis in W. somnifera.

Hypoglycemic and hypolipidemic effects of unsaponifiable matter from okra seed in diabetic rats.

BACKGROUND/OBJECTIVES: Okra seed is a rich source of various nutritional and bioactive constituents, but its mechanism of action is still unclear. The aim of this study was to evaluated the effects on glucose uptake and serum lipid profiles of unsaponifiable matter (USM) from okra seed in adipocytes and diabetic animal models. MATERIALS/METHODS: USM was prepared from okra seed powder by saponification. The contents of phytosterols and vitamin E in USM were measured. 3T3-L1 preadipocytes were cultured for 6 days with different concentrations of USM (0-200 µg/mL). The diabetic rats were administered with or without USM for 5 wk. RESULTS: In the USM, the contents of phytosterols and vitamin E were 394.13 mg/g USM and 31.16 mg/g USM, respectively. USM showed no cytotoxicity and led to an approximately 1.4-fold increase in glucose uptake in 3T3-L1 adipocytes. The treatment of USM also increased the expressions of peroxisome proliferator-activated receptor-γ and glucose transporter-4 in a dose-dependent manner in adipocytes. The body weight change was not significantly different in all diabetic rats. However, blood glucose and the weights of liver and adipose tissues were significantly reduced compared to those in the control diabetic rats. Treatment with USM decreased the levels of triglycerides, total cholesterol, and low-density lipoprotein cholesterol compared to the control group. The USM group also showed significantly decreased atherogenic indices and cardiac risk factors. CONCLUSION: These results suggest that USM from okra seed improves the hypoglycemic and hypolipidemic effects in diabetic rats, and provides valuable information for improving the functional properties of okra seed.

Anti-inflammatory Activity and Acute Toxicity Of Pereskia aculeata, In Zophobas morio Larvae.

Pereskia aculeata has been widely investigated due to its anti-inflammatory potential. Among the metabolites found in this species are the phytosterols beta-sitosterol (ß-SIT) and stigmasterol (STIG). The objective of the study was to evaluate the anti-inflammatory and toxicity activities of the hexane partition of P. aculeata (PHEX), as well as ß-SIT and STIG. PHEX was prepared and the phytosterols were quantified. In terms of toxicity against L929 fibroblast cells, PHEX showed toxicity up to 200 µg/mL; STIG and ß-SIT showed toxicity up to 25 µg/mL. PHEX inhibited 66% of nitric oxide radicals, while STIG and ß-SIT inhibited 33.73% and 34.94%, respectively. In an anti-inflammatory test against Zophobas morio larvae, all samples significantly reduced hemocyte levels. Additionally, the LD50 values were calculated: 229.6 mg/kg for PHEX, 101.5 mg/kg for STIG, and 103.8 mg/kg for ß-SIT. In conclusion, the study indicates that the phytosterols present in PHEX may contribute to its anti-inflammatory activity.

Synthesis of a Side Chain Alkyne Analogue of Sitosterol as a Chemical Probe for Imaging in Plant Cells.

Clickable chemical tools are essential for studying the localization and role of biomolecules in living cells. For this purpose, alkyne-based close analogs of the respective biomolecules are of outstanding interest. Here, in the field of phytosterols, we present the first alkyne derivative of sitosterol, which fulfills the crucial requirements for such a chemical tool as follows: very similar in size and lipophilicity to the plant phytosterols, and correct absolute configuration at C-24. The alkyne sitosterol FB-DJ-1 was synthesized, starting from stigmasterol, which comprised nine steps, utilizing a novel alkyne activation method, a Johnson-Claisen rearrangement for the stereoselective construction of a branched sterol side chain, and a Bestmann-Ohira reaction for the generation of the alkyne moiety.

Biochemical Properties of Bioactive Compounds in the Oil from Polish Varieties of Camelina sativa Cultivated in 2019-2022.

Cold-pressed Camelina oil is a traditional oil registered as a traditional food in Poland. Camelina oil has health-promoting properties and high oxidative stability. This may be due to the presence of various bioactive antioxidant compounds such as carotenoids, sterols and polyphenols. Bioactive compounds content in Camelina oil depends mainly on the varieties and on the conditions under which the crop was grown therefore the aim of the research was to analyse antioxidant bioactive compounds in oil from different cultivars of Camelina sativa seeds and to determine their relationship with oil parameters.

Phytosterols and the Digestive System: A Review Study from Insights into Their Potential Health Benefits and Safety.

Phytosterols are a large group of substances belonging to sterols-compounds naturally occurring in the tissues of plants, animals, and humans. The most well-known animal sterol is cholesterol. Among phytosterols, the most significant compounds are ß-sitosterol, stigmasterol, and campesterol. At present, they are mainly employed in functional food products designed to counteract cardiovascular disorders by lowering levels of 'bad' cholesterol, which stands as their most extensively studied purpose. It is currently understood that phytosterols may also alleviate conditions associated with the gastrointestinal system. Their beneficial pharmacological properties in relation to gastrointestinal tract include anti-inflammatory and hepatoprotective activity. Also, the anti-cancer properties as well as the impact on the gut microbiome could be a very interesting area of research, which might potentially lead to the discovery of their new application. This article provides consolidated knowledge on a new potential use of phytosterols, namely the treatment or prevention of gastrointestinal diseases. The cited studies indicate high therapeutic efficacy in conditions such as peptic ulcer disease, IBD or liver failure caused by hepatotoxic xenobiotics, however, these are mainly in vitro or in vivo studies. Nevertheless, studies to date indicate their therapeutic potential as adjunctive treatments to conventional therapies, which often exhibit unsatisfactory efficacy or serious side effects. Unfortunately, at this point there is a lack of significant clinical study data to use phytosterols in clinical practice in this area.

Profiling the Bioactive Compounds in Broccoli Heads with Varying Organ Sizes and Growing Seasons.

Broccoli is a rich source of diverse bioactive compounds, but how their contents are influenced by different growing seasons and variations in broccoli head sizes remains elusive. To address this question, we quantified sixteen known bioactive compounds and seven minerals in broccoli with varying head sizes obtained in two different growing seasons. Our results suggest that the contents of vitamin C, total phenols, carotenoids, and glucoraphanin were significantly higher in samples from the summer-autumn season, showing increases of 157.46%, 34.74%, 51.80%, and 17.78%, respectively, compared with those from the winter-spring season. Moreover, chlorogenic acid is a phenolic compound with relatively high contents among the six detected, while beta-sitosterol is the sterol with relatively high contents. Further, principal component analysis was conducted to rank the comprehensive scores of the profiles of phenolic compounds, phytosterols, and minerals, demonstrating that the broccoli samples grown during the summer-autumn season achieved the highest composite scores. Our results indicate that broccoli heads from the summer-autumn season are richer in a combination of bioactive compounds and minerals than those from the winter-spring season based on the composite score. This study extends our understanding of the nutrition profiles in broccoli and also lays the foundation for breeding broccoli varieties with improved nutrition quality.

Evaluation of sterols as markers of fungal spoilage in red pepper powder.

Red pepper powder (RPP) made from ground dried red pepper (Capsicum annuum L.) is prone to adulteration with fungal-spoiled RPP to gain unfair profits in Korea. This study aimed to investigate the effects of fungal infection on the ergosterol and phytosterol content of RPP and evaluate the potential of the sterol content as a marker for identifying fungal-spoiled RPP. Ergosterol was detected only in fungal-spoiled RPP and not in unspoiled RPP [

Encapsulation of antioxidants with colloidal lipid particles for enhancing the photooxidation stability of phytosterol in Pickering emulsions.

In order to prevent the photooxidation of phytosterols, a new type of Pickering emulsion was developed by regulating the oriented distribution of antioxidants in colloidal lipid particles (CLPs) at the oil-water interface. High-melting-point and low-melting-point lipids were tested to modulate their protective effect against phytosterols photooxidation. Results showed that CLPs could stabilize Pickering emulsion and encapsulate antioxidants, providing a dual functional delivery system for phytosterols protection. The Pickering emulsion formed had a particle size of around 350-820 nm, and the crystallization and melting temperatures of tripalmitin particles were approximately 32 °C and 63.8 °C, respectively. The addition of tributyrin or tricaprylin reduced the crystallization and melting temperatures of Pal CLPs and improved the photooxidation emulsion stability. The prepared Pickering emulsion remained stable for a maximum of 12 days under accelerated light-induced oxidation. Among all formulations, the emulsion primarily composed of tripalmitin CLPs, with added tributyrin and resveratrol, exhibited the highest photooxidation stability.

Effects of phytosterol supplementation on lipoprotein subfractions and LDL particle quality.

Phytosterols are natural components of plant-based foods used as supplements because of their known cholesterol-lowering effect. However, their effects on lipoprotein subfractions and the quality of the LDL particle have not been studied in greater detail. We aimed to evaluate the effects of phytosterols supplements on lipids, lipoproteins subfractions, and on the quality of LDL. A prospective, pilot-type, open label, cross-over study, randomized 23 males in primary prevention of hypercholesterolemia to receive diet or diet plus phytosterol (2.6 g in 2 doses, with meals) for 12 weeks, when treatments were switched for another 12 weeks. Lipoprotein subfractions were analyzed by electrophoresis in polyacrylamide gel (Lipoprint System®). The Sampson equation estimated the small and dense (sd) and large and buoyant (lb) LDL subfractions from the lipid profile. Quality of LDL particle was analyzed by Z-scan and UV-vis spectroscopy. Primary outcome was the comparison of diet vs. diet plus phytosterols. Secondary outcomes assessed differences between baseline, diet and diet plus phytosterol. Non-parametric statistics were performed with p < 0.05. There was a trend to reduction on HDL-7 (p = 0.05) in diet plus phytosterol arm, with no effects on the quality of LDL particles. Heatmap showed strong correlations (ρ > 0.7) between particle size by different methods with both interventions. Diet plus phytosterol reduced TC, increased HDL-c, and reduced IDL-B, whereas diet increased HDL7, and reduced IDL-B vs. baseline (p < 0.05, for all). Phytosterol supplementation demonstrated small beneficial effects on HDL-7 subfraction, compared with diet alone, without effects on the quality of LDL particles.This trial is registered in Clinical Trials (NCT06127732) and can be accessed at https://clinicaltrials.gov .

Unveiling the molecular mechanisms: dietary phytosterols as guardians against cardiovascular diseases.

Until recently, the main pharmaceuticals used to control cholesterol and prevent cardiovascular disease (CVD) were statin-related drugs, known for their historical side effects. Therefore, there is growing interest in exploring alternatives, such as nutritional and dietary components, that could play a central role in CVD prevention. This review aims to provide a comprehensive understanding of how natural phytosterols found in various diets combat CVDs. We begin with a description of the overall approach, then we explore in detail the different direct and indirect mechanisms that contribute to reducing cardiovascular incidents. Phytosterols, including stigmasterol, ß-sitosterol, ergosterol, and fucosterol, emerge as promising molecules within nutritional systems for protection against CVDs due to their beneficial effects at different levels through direct or indirect cellular, subcellular, and molecular mechanisms. Specifically, the mentioned phytosterols exhibit the ability to diminish the generation of various radicals, including hydroperoxides and hydrogen peroxide. They also promote the activation of antioxidant enzymes such as superoxide dismutase, catalase, and glutathione, while inhibiting lipid peroxidation through the activation of Nrf2 and Nrf2/heme oxygenase-1 (HO-1) signaling pathways. Additionally, they demonstrate a significant inhibitory capacity in the generation of pro-inflammatory cytokines, thus playing a crucial role in regulating the inflammatory/immune response by inhibiting the expression of proteins involved in cellular signaling pathways such as JAK3/STAT3 and NF-κB. Moreover, phytosterols play a key role in reducing cholesterol absorption and improving the lipid profile. These compounds can be used as dietary supplements or included in specific diets to aid control cholesterol levels, particularly in individuals suffering from hypercholesterolemia.

Blood Phytosterol Concentration and Genetic Variant Associations in a Sample Population.

The main objective of this study was to determine plasma levels of PS and to study SNVs rs41360247, rs4245791, rs4148217, and rs11887534 of ABCG8 and the r657152 SNV at the ABO blood group locus in a sample of a population treated at our hospital, and to determine whether these SNVs are related to plasma PS concentrations. The secondary objective was to establish the variables associated with plasma PS concentrations in adults. Participants completed a dietary habit questionnaire and a blood sample was collected to obtain the following variables: campesterol, sitosterol, sitostanol, lanosterol, stigmasterol, biochemical parameters, and the SNVs. In addition, biometric and demographic variables were also recorded. In the generalized linear model, cholesterol and age were positively associated with total PS levels, while BMI was negatively related. For rs4245791, homozygous T allele individuals showed a significantly lower campesterol concentration compared with C homozygotes, and the GG alleles of rs657152 had the lowest levels of campesterol compared with the other alleles of the SNV. Conclusions: The screening of certain SNVs could help prevent the increase in plasma PS and maybe PNALD in some patients. However, further studies on the determinants of plasma phytosterol concentrations are needed.

Optimizing niger seed (Guizotia abyssinica) oil quality: A comprehensive analysis of infrared-heat induced changes in bioactive profile, physiochemical attributes, and oxidative stability.

Infrared heating (IRH) at 140, 160, and 180°C for varying durations (5, 10, and 15 min) was employed for improving the niger (Guizotia abyssinica) seed oil (NSO) quality for diverse food applications. The study explored changes in phenolic profile, oxidative stability index (OSI), tocopherols, phytosterols, fatty acid profiles, and physicochemical attributes of NSO. Upon IRH at 180°C for 10 min, the oil yield, total phenolic, and flavonoid contents increased from 33.09% to 40.56%, 6.67 to 173.62 mg GAE/kg, and 24.76 to 120.64 mg QE/kg, respectively. The viscosity, chlorophylls, carotenoids, radical scavenging activity, OSI, caffeic, protocatechuic, vanillic, and syringic acids were highest upon IRH at 180°C for 15 min. The tocopherols and phytosterols initially augmented while decremented upon raising IRH conditions. The infrared spectra indicated no adverse impact of IRH on NSO quality. The appropriate IRH conditions can be considered for improving NSO quality and making it valuable for various edible products.

Dietary supplementing phytosterols improves the metabolic status of perinatal cows revealed by plasma metabolomics and faecal microbial metabolism.

Objective: Previous research reported that dietary addition with phytosterols improved the energy utilisation of the rumen microbiome, suggesting its potential to alleviate the negative energy balance of perinatal cows. This experiment aimed to explore the effects of feeding phytosterols on the metabolic status of perinatal cows through plasma metabolomics and faecal bacteria metabolism. Methods: Ten perinatal Holstein cows (multiparous, 2 parities) with a similar calving date were selected four weeks before calving. After 7 days for adaptation, cows were allocated to two groups (n=5), which respectively received the basal rations supplementing commercial phytosterols at 0 and 200 mg/d during a 42-day experiment. The milk yield of each cow was recorded daily after calving. On days 1 and 42, blood and faeces samples were all collected from perinatal cows before morning feeding for analysing plasma biochemicals and metabolome, and faecal bacteria metabolism. Results: Dietary addition with phytosterols at 200 mg/d had no effects on plasma cholesterol and numerically increased milk yield by 1.82 kg/d (p>0.10) but attenuated their negative energy balance in perinatal cows as observed from the significantly decreased plasma level of ß-hydroxybutyric acid (p=0.002). Dietary addition with phytosterols significantly altered 12 and 15 metabolites (p<0.05) within the plasma and faeces of perinatal cows, respectively. Of these metabolites, 5 upregulated plasma fatty acids indicated an improved energy status (i.e., C18:1T, C14:0, C17:0, C18:0, and C16:0). Milk yield negatively correlated with plasma concentrations of ketone bodies (p=0.035) and 5-methoxytryptamine (p=0.039). Furthermore, dietary addition with phytosterols at 200 mg/d had no effects on fermentation characteristics and bacterial diversity of cow faeces (p>0.10) but improved potentially beneficial bacteria such as Christensenellaceae family (p<0.05) that positively correlated with feed efficiency. Conclusion: Dietary addition with phytosterols at 200 mg/d could effectively improve the energy status in perinatal cows by attenuating their negative energy balance.

Deciphering the effect of phytosterols on Alzheimer's disease and Parkinson's disease: the mediating role of lipid profiles.

BACKGROUND: Studies have suggested that blood circulating phytosterols, plant-derived sterols analogous to cholesterol, were associated with blood lipid levels and the risk of Alzheimer's disease (AD) and Parkinson's disease (PD). This Mendelian randomization (MR) study is performed to determine the causal effect of circulating phytosterols on AD and PD and evaluate the mediation effect of blood lipids. METHODS: Leveraging genome-wide association studies summary-level data for phytosterols, blood lipids, AD, and PD, univariable and multivariable MR (MVMR) analyses were conducted. Four types of phytosterols (brassicasterol, campesterol, sitosterol, and stigmasterol), three blood lipids parameters (high-density lipoprotein cholesterol [HDL-C], non-HDL-C, and triglyceride), two datasets for AD and PD were used. Inverse-variance weighted method was applied as the primary analysis, and false discovery rate method was used for adjustment of multiple comparisons. RESULTS: Using the largest AD dataset, genetically proxied higher levels of stigmasterol (OR = 0.593, 95%CI = 0.431-0.817, P = 0.004) and sitosterol (OR = 0.864, 95%CI = 0.791-0.943, P = 0.004) significantly correlated with a lower risk of AD. No significant associations were observed between all four types of phytosterols levels and PD. MVMR estimates showed that the above causal associations were missing after integrating the blood lipids as exposures. Sensitivity analyses confirmed the robustness of these associations, with no evidence of pleiotropy and heterogeneity. CONCLUSION: The study supports a potential beneficial role of blood stigmasterol and sitosterol in reducing the risk of AD, but not PD, which is dependent on modulating blood lipids. These insights highlight circulating stigmasterol and sitosterol as possible biomarkers and therapeutic targets for AD.

Sterol Migration during Rotational Frying of Food Products in Modified Rapeseed and Soybean Oils.

This study explores the impact of rotational frying of three different food products on degradation of sterols, as well as their migration between frying oils and food. The research addresses a gap in the existing literature, which primarily focuses on changes in fat during the frying of single food items, providing limited information on the interaction of sterols from the frying medium with those from the food product. The frying was conducted at 185 ± 5 °C for up to 10 days where French fries, battered chicken, and fish sticks were fried in succession. The sterol content was determined by Gas Chromatography. This research is the first to highlight the influence of the type of oil on sterol degradation in both oils and food. Notably, sterols were found to be most stable when food products were fried in high-oleic low-linolenic rapeseed oil (HOLLRO). High-oleic soybean oil (HOSO) exhibited higher sterol degradation than high-oleic rapeseed oil (HORO). It was proven that cholesterol from fried chicken and fish sticks did not transfer to the fried oils or French fries. Despite initially having the highest sterol content in fish, the lowest sterol amount was recorded in fried fish, suggesting rapid degradation, possibly due to prefrying in oil with a high sterol content, regardless of the medium used.

A SCYL2 gene from Oryza sativa is involved in phytosterol accumulation and regulates plant growth and salt stress.

Rice is a crucial food for humans due to its high nutritional value. Phytosterols, essential components of the plant membrane lipid bilayer, play a vital role in plant growth and contribute significantly to lipid-lowering, antitumor, and immunomodulation processes. In this study, SCY1-like protein kinases 2 (SCYL2) was found to be closely related to the accumulation of phytosterols. The levels of campesterol, stigmasterol, and ß-sitosterol significantly increased in transgenic rice seeds, husks, and leaves, whereas there was a considerable reduction in scyl2 plants. Subsequent investigations revealed the crucial role of SCYL2 in plant development. Mutations in this gene led to stunted plant growth while overexpressing OsSCYL2 in Arabidopsis and rice resulted in larger leaves, taller plants, and accelerated development. When subjected to salt stress, Arabidopsis plants overexpressed OsSCYL2 showed significantly higher germination rates than wild-type plants. Similarly, transgenic rice seedlings displayed better growth than both ZH11 and mutant plants, exhibiting lower malondialdehyde (MDA) content and higher peroxidase (POD), and catalase (CAT) activities. Conversely, scyl2 plants exhibited more yellow leaves or even death. These findings suggested that OsSCYL2 proteins might be involved in phytosterols synthesis and play an important role during plant growth and development. This study provides a theoretical basis for developing functional rice.

Solving the Jigsaw puzzle of phytosterol diversity by a novel sterol methyltransferase from Zea mays.

Phytosterols are vital structural and regulatory components in plants. Zea mays produces a series of phytosterols that are specific to corn. However, the underline biosynthetic mechanism remains elusive. In this study, we identified a novel sterol methyltransferase from Z. mays (ZmSMT1-2) which showed a unique feature compared with documented plant SMTs. ZmSMT1-2 showed a substrate preference for cycloartenol. Using S-adenosyl-L-methionine (AdoMet) as a donor, ZmSMT1-2 converted cycloartenol into alkylated sterols with unique side-chain architectures, including Δ25(27) (i.e., cyclolaudenol and cycloneolitsol) and Δ24(25) (i.e., cyclobranol) sterols. Cycloneolitsol is identified as a product of SMTs for the first time. Our discovery provides a previously untapped mechanism for phytosterol biosynthesis and adds another layer of diversity of sterol biosynthesis.