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BACKGROUND: The INFOGEST model is a standardized general in vitro digestion study, but it cannot accurately simulate the fatty acid release process of lipids in the stomach and small intestine. In this study, the internationally universal INFOGEST 2019 was used as the basic model and flaxseed oil emulsion was used as the research object. In various improvement models, the effect of fatty acid release rate on the oxidation stability of flaxseed oil was assessed by adding rabbit stomach extract and changing the order of bile salts addition. RESULTS: With the presence of rabbit gastric extract, flaxseed oil emulsion flocculation and coalescence in stomach were reduced, and the absolute value of ζ‐potential increased. Moreover, the release rate of fatty acids in the small intestine increased by 12.14%. The amount of lipid oxidation product (i.e. hexanal) in the gastric and intestinal phases increased by 0.08 ppb. In addition, the fatty acid release rate in the small intestine phase increased by 5.85% and the hexanal content increased by 0.011 ppb in the digestion model of adding bile salts before adjusting the pH in the small intestine phase compared with the model of adjusting the pH first and then adding bile salts. CONCLUSION: The results obtained from this study will contribute to finding the most suitable static digestion model for simulating digestion and oxidation of lipid during lipid gastrointestinal digestion. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In the present, oil pressing is still the main process for extracting oil from flaxseed in China, but it cannot achieve efficient utilization of functional materials in flaxseed, such as flaxseed gum and lignin secoisolariciresinol diglycoside (SDG). So a comprehensive process that produces multiple products from flaxseed needs to be developed. On the basis of the structural characteristics that the flaxseed gum is in the outermost layer of flaxseeds, the grinding degumming technology using high-speed rotating sand roller grind flaxseed surface is studied before in our laboratory. Model 150 flaxseed degumming machine was designed and manufactured according to this technology, it is composes of motor, sand roller, sieve, gum powder collector etc. Electronic motor is used in the machine to drive the sand roller with high-speed rotation inner the sieve to grind flaxseed, the gum powder flow out the sieve and is collected, the sand roller length and diameter is 800 and 146 mm, the cylindrical sieve diameter is 158 mm with uniform distribution of F1.5 mm sieve size. In this paper, the feasibility of Model 150 flaxseed degumming machine was studied. Based on that, the research work of flaxseed degumming and oil pressing co-process was carried out with the commodity flaxseed from Gansu as the research material. The results showed that: the machine was able to obtain flaxseed gum-powder successfully when flaxseed flow rate was controlled at 40 to 220 kg/h. The rate of gum-powder grinded from flaxseed was 6.5%±0.3%. The viscosity of the defatted gum-powder was (5100 ± 520) mPaos. The oil contents of flaxseed and the degummed flaxseed were 39.30%±0.25% and 41.62%±0.22%, respectively. By using the method of adding 30% flaxseed cake to degummed flaxseed, the oil of degummed flaxseed can be screw pressed successfully. The oil yield pressed from degummed flaxseed was 34.65%±0.43%, higher than that pressed twice from flaxseed (33.94% ± 0.43%)when the flaxseed was pressed with the screw pressing machine without degumming. By the combination of degumming and screw-pressing for flaxseed processing, two benefits were achieved, they were: increase number of products and high pressed oil yield. The research results can provide reference for flaxseed processing. [ABSTRACT FROM AUTHOR]

In this study, rapeseed was pretreated by steam explosion pretreatment technology and subsequently pressed to prepare rapeseed oil. GC, UPLC, and HPLC techniques were employed to analyze the quality characteristics of the rapeseed oil, including the canolol content and other quality characteristics. Additionally, the effect of steam explosion pretreatment technology on the canolol content of rapeseed oil was studied and the formation mechanism of canolol elucidated. The results revealed that when the steam explosion pressure reached 1.0 MPa, the canolol content of the tested oil increased from 41.21 to 2,168.69 mg/kg (52.63‐fold increase) and that sinapic acid played a significant role in the conversion of canolol. Thus, the sinapine was converted into the intermediate (sinapic acid) by hydrolysis, which in turn was transformed into canolol through decarboxylation. The instantaneous high‐energy environment generated by steam explosion pretreatment could intensify the hydrolysis and decarboxylation reactions of sinapine and sinapinic acid, thereby significantly increasing the canolol content of the oil. To prove the superiority of steam explosion pretreatment, we compared it with other pretreatment technologies, including traditional high‐temperature roasting and popular microwave pretreatment. The results revealed that rapeseed oil prepared by steam explosion pretreatment displayed the best quality characteristics. This study can be a reference for the preparation process of rapeseed oil with superhigh canolol content and superior quality characteristics using steam explosion pretreatment. [ABSTRACT FROM AUTHOR]

In this study, flaxseed was pretreated by steam explosion technology and subsequently pressed to prepare flaxseed oil. GC, UPLC, HPLC, and GC‐MS techniques were used to analyze the quality characteristics of the prepared flaxseed oil. These included the food safety risk indices, micronutrient components, and oxidative stability. The effects of different steam explosion pressures on the quality characteristics and relative volatile components of flaxseed oil were also investigated. The results revealed that steam explosion pretreatment technology could significantly increase the oil yield, improve micronutrient content, and strengthen the oxidation stability of the product. Moreover, the food safety risk indices (e.g., benzopyrene) were controlled within a reasonable range, while the fatty acid content remained almost unchanged. Notably, the relative pyrazine content in the total volatile components of flaxseed oil was 68.25% when the steam explosion pressure reached 1.2 MPa. This was considered as the main factor that contributed to the unique concentrated fragrance of the produced flaxseed oil. To prove the superiority of the steam explosion pretreatment, we compared this technique with traditional high‐temperature roasting and popular microwave pretreatment techniques. The results revealed that flaxseed oil prepared by steam explosion pretreatment displayed the best quality characteristics and most concentrated fragrance. Thus, steam explosion technology shows great potential for application to produce high‐quality concentrated fragrance flaxseed oil. This study provides significant reference and guidance for the preparation process of flaxseed oil. [ABSTRACT FROM AUTHOR]

[Display omitted] • DHA improves systemic glucose metabolism disorders. • DHA prevents hippocampal neuroinflammation. • DHA attenuates hippocampal oxidative stress. • DHA inhibits hippocampal amyloid formation and Tau phosphorylation. • DHA ameliorates hippocampal insulin resistance. • DHA improves cognitive function. Diminished brain insulin sensitivity is associated with reduced cognitive function. Docosahexaenoic acid (DHA) is known to maintain normal brain function. This study aimed to determine whether DHA impacts hippocampal insulin sensitivity and cognitive function in aged rats fed a high-fat diet (HFD). Eight-month-old female Sprague-Dawley rats were randomly divided into three groups (n = 50 each). Rats in the aged group, HFD group, and DHA treatment group received standard diet (10 kcal% fat), HFD (45 kcal% fat), and DHA-enriched HFD (45 kcal% fat, 1% DHA, W/W) for 10 months, respectively. Four-month-old female rats (n = 40) that received a standard diet served as young controls. Neuroinflammation, oxidative stress, amyloid formation, and tau phosphorylation in the hippocampus, as well as systemic glucose homeostasis and cognitive function, were tested. DHA treatment relieved a block in the insulin signaling pathway and consequently protected aged rats against HFD-induced hippocampal insulin resistance. The beneficial effects were explained by a DHA-induced decrease in systemic glucose homeostasis dysregulation, hippocampal neuroinflammation and oxidative stress. In addition, DHA treatment broke the reciprocal cycle of hippocampal insulin resistance, Aβ burden, and tau hyperphosphorylation. Importantly, treatment of model rats with DHA significantly increased their cognitive capacity, as evidenced by their increased hippocampal-dependent learning and memory, restored neuron morphology, enhanced cholinergic activity, and activated cyclic AMP-response element-binding protein. DHA improves cognitive function by enhancing hippocampal insulin sensitivity. [ABSTRACT FROM AUTHOR]

The linseed gum/cellulose composite hydrogels were successfully fabricated by mixing cellulose and linseed gum solutions dissolved in the NaOH/urea aqueous system and cross-linked with epichlorohydrin. The morphology and structure of the composite hydrogels were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD) and thermogravimetric analysis (TGA). The swelling ratio and water retention properties were investigated. The results revealed that linseed gum mainly contributed to water adsorption, whereas the cellulose acted as a backbone to strengthen the porous structure. This work provided a simple way to prepare cellulose-based superabsorbent hydrogels, which could be potentially applied as an effective water conservation material in agriculture. [ABSTRACT FROM AUTHOR]

Abstract: A novel production process of biodiesel using magnetically stabilized fluidized bed reactor (MSFBR) has been developed based on cottonseed oil and the reaction conditions were also studied. The reactant flow rate and magnetic field intensity affects on the magnetic catalytic particles behavior in the column were performed, and the transesterification reaction conditions of cottonseed oil were investigated in MSFBR with nanometer magnetic catalytic particles. Under the suitable reaction conditions of methanol/oil molar ratio 8:1, 40 cm3 min−1 flow rate, 225 Oe magnetic field intensity and temperature of 65 °C, the conversion efficiency reaches to 97% in 100 min. The stability and recovery of the magnetic catalytic particles in MSFBR are much better than that in autoclave stirred reactor. The result shows that most of the resultant cottonseed oil biodiesel parameters comply with the limits established by representative biodiesel standards. [Copyright &y& Elsevier]

As a natural plant-derived oil-in-water emulsion, oil bodies (OBs) with fine membrane structure have a great potential to be a typical green entrapping system. The dense membrane of OBs protects the interior readily oxidizable substance, but also severely blocks the passage of biologically active substances. Given full considerations of both the mobility and rigidity of the OBs membrane, in this work, tepidity-ultrasonic (TU) method was firstly applied to incorporate β-carotene within flaxseed oil bodies (FOB). Laser Scanning Confocal Microscopy (LSCM), Atomic force microscopy (AFM) and Cryo-Scanning Electron Microscope (Cryo-SEM) measurements demonstrated that TU could induce the transformation of FOB membrane and greatly promoted β-carotene encapsulation into FOB interior. In consistent with rheology, the infrared, ultraviolet and fluorescence spectra of the membrane protein, as well as force-deformation curves confirmed that the inserted β-carotene weaken the interaction of components in the membrane to a sharp reduction in membrane stiffness. The subsequent ultrasonic triggered interfacial membrane remodeling and particle size reduction, causing a significant improvement of interfacial membrane stiffness nearly back its original state and ultimately improving the stability of the system. The optimal encapsulation rate of β-carotene (96.88%) could be obtained at optimized ultrasonic condition. After 30-day storage, the relative encapsulation efficiency of β-carotene in FOB-β-TU remained at 84.06%. Thus, this paper reveals that the synergistic effect of tepidity-stirring and ultrasonic provides the possibility for solvent-free assisted encapsulation of hydrophobic bioactive substances in natural OBs. This easily applicable method is also conducive to fulfill its application in multiple food processing. [Display omitted] • β-carotene incorporation and tepidity treatment changed the interaction between membrane protein and phospholipids • The translocation of interfacial protein may provide a pathway for β-carotene accessing. • Tepidity-ultrasonic successful promoted the entrapment of β-carotene into natural plant-derived FOB. • Interfacial membrane stiffness showed a significant tendency to return to the original state after ultrasound. • Ultrasound triggered interfacial membrane remodeling and ultimately improving the system stability. [ABSTRACT FROM AUTHOR]

The present study aimed to use a chemometric study to compare the in-vitro antioxidant activities and bioactive compounds of flaxseed based on the variety and geographical origins, and further explore the specific components constructed the endogenous antioxidant system of flaxseed in China. The differential contents of α-linolenic acid (35.83-58.91%), lignans (11.37-33.31 mg/g), total phenolic acids (109.93-246.88 mg/100 g) and phytosterols (56.52-125.12 mg/g) of 32 flaxseed varieties were observed. Concomitantly, the in-vitro antioxidant activities varied from 32.56 to 46.22 mg TE/100 g, 0.58 to 1.08 mg TE/g, and 14.22 to 36.14 mmol TE/g as determined by the 2,2’-diphenyl-1-picrylhydrazyl radical (DPPH), ferric reducing antioxidant power (FRAP) and 2,2′-azinobis-(3-ethylbenzthiazoline 6-sulfonic acid) (ABTS) assays, respectively. Significant correlations were found between the antioxidant activities and contents of free syringic acid, p-coumaric acid glucoside and secoisolariciresinol diglucoside (SDG) (p < 0.01). Principal component analysis showed a relatively dispersed distribution between samples, which was not effective enough to determine the geographical origins of the flaxseed samples. Hierarchical cluster analysis allowed flaxseed samples to be grouped based on their in-vitro antioxidant activities and bioactive component contents, primarily in relation to variety specificity. [ABSTRACT FROM AUTHOR]

Aging is a principal risk factor for neurodegenerative diseases and especially shares similar pathologic mechanisms to Alzheimer’s disease (AD). Amyloid-β (Aβ) plaques deposition and neurofibrillary tangles (NFTs) are the prominent age-dependent pathologies implicated in the cognitive deficits. Accumulation of mis-folded proteins in the endoplasmic reticulum triggers a cellular stress response called the unfolded protein response (UPR), the activation of which is increased in AD patients. However, the UPR relates to the pathological hallmarks of aging is still elusive. In this study, we report that long-term supplement of α-linolenic acid (ALA), starting before the onset of disease symptoms (6 month-old), prevents the age-related memory deficits during natural aging. The amelioration of the memory impairment is associated with a decrease in UPR related markers [glucose regulated protein 78 (GRP78), protein kinase RNA-like endoplasmic reticulum kinase (PERK), eukaryotic Initiation Factor 2α (eIF2α)]. ALA suppressed the PERK/eIF2α signaling, which may be responsible for multifaceted memory-deteriorating and neurodegenerative mechanisms, including inhibition of Aβ production by suppressing β-site APP-cleaving enzyme 1 (BACE1) expression, enhancement of cAMP response element binding protein (CREB) function via down-regulating activating transcription factor 4 (ATF4), and suppression of Tau phosphorylation by inhibiting glycogen synthase kinase 3β (GSK-3β) pathway. Taken together, our findings provide new insights into the link between ALA and PERK/eIF2α signaling, which could contribute to a better understanding of an ALA-mediated protective effect in aging-associated neuropathology. [ABSTRACT FROM AUTHOR]

In this study, different oil extraction technologies were used to obtain flaxseed oil with different lipid concomitants, and the influences of endogenous lipid concomitants on the stability and digestion properties of flaxseed oil emulsions were investigated. Compared with cold-press (CP), microwave pretreatment coupled with cold-press (MPCP) and accelerated solvent extraction (ASE) contributed to the accumulation of hydrophilic and lipophilic lipid concomitants, respectively. Subcritical fluid extraction (SFE) and supercritical CO 2 extraction (SCO 2 E) were conducive to the accumulation of amphipathic lipid concomitants. After emulsification, ASE-flaxseed oil emulsions had the lowest initial particle size due to the high content of amphiphilic lipid concomitants phospholipids. Phospholipids are spontaneously adsorbed on the interface of flaxseed oil and water. Antioxidative lipid concomitants (phenols, phytosterols, carotenoids, flavonoids, and cyclolinopeptides (CLs)) in MPCP-flaxseed oil improved the oxidative stability of emulsions. After digestion, ASE-flaxseed oil emulsion presented the highest FFAs% (∼78%) owing to smaller particle size. The release of FFAs decreased by 5%–10% in MPCP-, SCO 2 E-, and SFE-flaxseed oil emulsions ascribed to the high content of phenols. In conclusion, MPCP and ASE are powerful flaxseed oil extraction technologies for improving the stability and digestion of emulsions, respectively. [Display omitted] • The methods of CP, MPCP, ASE, SCO 2 E and ASE were used to extract flaxseed oil. • Oil extraction methods influenced the content of lipid concomitants in flaxseed oil. • SCO 2 E-flaxseed oil emulsions were unstable for the prooxidative activity of FFAs. • MPCP-flaxseed oil emulsion was stable for high content of tocopherols, flavonoids. • ASE-flaxseed oil emulsions promoted FFAs release for its lower diameter size. [ABSTRACT FROM AUTHOR]

Abstract: A solid base catalyst Na2SiO3 was prepared by microwave heating. The catalyst was used to catalyze the transesterification reactions for the production of fatty acid methyl esters from cottonseed oil. The optimum conditions of the catalyst preparation and transesterification reactions were investigated by orthogonal experiments. The catalyst with the highest catalytic activity was obtained using microwave power of 640 W, microwave irradiation time of 6 min, catalyst particle size of 60 mesh. The catalyst was characterized with X-ray diffraction (XRD), scanning electron micrographs (SEM), and the results showed the catalyst Na2SiO3 has good microstructure. Under the transesterification conditions of methanol/oil molar ratio of 6:1, catalyst dosage of 5%, reaction temperature of 65 °C, reaction time of 100 min and stirring speed of 400 rpm, the yield of methyl esters was 97.6%. The lifetime of the solid base catalysts by different process methods (microwave heating and conventional electric heating) was no significant differences, but microwave heating may be more economical than conventional electric heating. [Copyright &y& Elsevier]

The oil and protein of dehulled cold-pressed double-low rapeseed cake was extracted by an aqueous enzymatic process. The rapeseed cake was treated by the chosen combined enzymes of Viscozyme L and Alcalase 2.4L (VLA,1:1,w/w). Preliminary experiments and Response Surface Methodology (RSM) were used to study the effects of enzyme concentration, incubation time and water-to-cake ratio on the extraction yield of oil and protein. This is how the desirable conditions were obtained. Transmissive electron microscope photo showed that after cold-pressing the cell structure of rapeseed was partly damaged while dehulling had little effect on the cell structure of rapeseed. In RSM experiments water-to-cake ratio showed significant effects on the extraction of oil and protein (P<0.05),while incubation time only showed significant effects on protein yield (P<0.05).The desirable conditions were as follows: 1.0% concentration (w/w) of VLA; water-to-cake ratio(w/w),6:1; 80 min incubation time. Under this condition, the extraction yield of protein and oil were 82.10% and 71.89%, respectively. Through combining both the cold-press and the aqueous enzymatic processes together, the total oil yield reached 91.6%, which is higher than the normal cold-press process or the aqueous enzymatic extraction process alone. [ABSTRACT FROM AUTHOR]

The main proposal of this study was to evaluate in vivo whether flaxseed oils fortified with micronutrients would have beneficial effects on lipid profile and antioxidant status in high-fat fed rats. Male Wistar rats were fed synthetic diets containing 10% of flaxseed oil (FO), phytosterols (PS) fortified FO (PS-FO), vitamin E (VE) fortified FO (VE-FO), VE, and PS fortified FO (VE-PS-FO), respectively, for 4 wk. The results showed that VE fortified FO enhanced the enzymatic (SOD and GPX) and nonenzymatic (GSH and VE) antioxidant system, lowered the lipid peroxide (TBARS) concentration compared with FO ( P < 0.05). And FO fortified with PS significantly reduced the plasma TG, TC and LDL-C levels, and hepatic TG and TC levels of rats compared with FO ( P < 0.05), but had no significant effect on antioxidant defense capacities. Combined addition of VE and PS in FO had a synergetic effect. These results indicated that flaxseed oils fortified micronutrients VE and PS may contribute to reduce the risk factors of cardiovascular disease (CVD) by improving plasma antioxidant defenses and lipids profiles. Practical Application: Flaxseed oil usually contains greater than 50% of alpha-linolenic acid (ALA) and is a desire origin for n-3 PUFA. But consuming high dose of n-3 PUFA could lead to oxidative damage through free radical-chain reaction in cellular and subcellular membranes. Our studies showed that a regular intake of VE and PS fortified flaxseed oils increased antioxidant defenses and ameliorated lipids profile in high-fat fed rats, and these indicated that the flaxseed oil fortified with these micronutrients might reduce the incidence of CVD. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the functional properties of Ginkgo seed protein isolate (GPI), Ginkgo seed globulin protein (GGP) and Ginkgo seed albumin protein (GAP) extracted from Ginkgo biloba seeds were investigated. The protein contents of GPI, GGP and GAP were 91.0%, 93.4% and 87.8%, respectively in the samples in which the sugar, polyphenol and crude fibre were removed by the preparation procedure. For functional properties of Ginkgo seed proteins in the natural state, GAP showed the highest oil-absorption capacity (9.3ml/g), foaming capacity (67.8%), emulsifying capacity (65.4%) and emulsion stability (90.6%); while GPI showed the highest water absorption capacity (1.93ml/g), and GGP showed the highest foam stability (55.5%). The differences of the chemical components, surface hydrophobicity, disulphide bond (SS) and sulfhydryl group (SH) contents of GPI, GGP and GAP, which were correlated significantly with functional properties of Ginkgo seed proteins, were also investigated. The improved functional properties, such as water absorption capacity, solubility, foaming properties and emulsifying properties of Ginkgo seed proteins were observed in a pH range of 8.0–10.0 or sodium chloride concentration of 0.5–0.75M. [ABSTRACT FROM AUTHOR]

Abstract: A new antioxidation protein named G4b was purified from Ginkgo biloba seed albumin. The results of chemical colorimetry and chemiluminescence methods showed that the hemi-inhibitory concentration (IC50) of G4b on the hydroxyl radical were 78.1μg/mL and 115.1μg/mL, and the IC50 on DPPH was 100.7μg/mL, while the IC50 on the superoxide anion and DNA injury were 23μg/mL and 27μg/mL, respectively, and the abundance of sulfur amino acids and aromatic amino acids contained in G4b might contribute to its strong antioxidation properties. G4b is a kind of homogeneous and novel protein with a molecular mass of 29,247Da, consisting of two peptides with similar molecular weights linked by a disulfide bond. Result of β-elimination reaction showed that G4b is connected with a small quantity of polysaccharide by an oxygen-glucosidic bond. [Copyright &y& Elsevier]

[Display omitted] • Different structural flaxseed lignans inhibited FO oxidation in HSPC-emulsions. • SECO and FLEH enhanced the physical stability of emulsions. • The free radical membrane permeation was highly inhibited by SECO and FLEH. • The mechanism mainly related to the interactions between HSPC and flaxseed lignans. • The flaxseed lignans decreased the lipolysis by lipase during simulated digestion. The influences of the different structural flaxseed lignans on flaxseed oil (FO) emulsions during storage and digestion were investigated, focusing on their interfacial behavior. From perspective of interface, more than 60% of secoisolariciresinol (SECO) and the acidic hydrolysates of flaxseed lignan macromolecule (FLEH) were located on the interface of FO emulsions. It improved the stability of FO emulsions both during storage and digestion by inhibiting of free radical penetration and improving their targeted antioxidative activity. By comparison, the secoisolariciresinol diglucoside (SDG) and the alkaline hydrolysates of flaxseed lignan macromolecule (FLE) largely located in the aqueous and exerted lower antioxidative efficiency in emulsions. Moreover, SDG, SECO, FLE and FLEH slowed down the digestive rate of FO in emulsions, which might be due to flaxseed lignans inhibited the activity of digestive enzymes. These findings suggested that the different structural flaxseed lignans had the potential as antioxidants in emulsions during storage and digestion. [ABSTRACT FROM AUTHOR]

The digestion of flaxseed polysaccharides (FSP) in simulated saliva, gastric and small intestine conditions was assessed, as well as in vitro fermentation of FSP by human gut microbiota. FSP was not degraded in the simulated digestive systems (there was no change in molecular weight or content of reducing sugars), indicating that ingested FSP would reach the large intestine intact. Changes in carbohydrate content, reducing sugars and culture pH suggested that FSP could be broken down and used by gut microbiota. FSP modulated the composition and structure of the gut microbiota by altering the Firmicutes/Bacteroidetes ratio and increasing the relative abundances of Prevotella, Phascolarctobacterium, Clostridium and Megamonas, which can degrade polysaccharides. Meanwhile, FSP fermentation increased the concentration of short-chain fatty acids, especially propionic and butyric acids. Our results indicate that FSP might be developed as a functional food that benefits gut health. [ABSTRACT FROM AUTHOR]

• Flaxseed polysaccharide supplementation ameliorated the metabolic syndrome in HFD mice. • Flaxseed polysaccharide supplementation increased the proportion of Akkermansia and Bifidobacterium. • The improvement of lipid metabolism disorder was associated with the modulation of the gut microbiota. Flaxseed (Linum usitatissimum L.) is known as healthy food for its anti-obesity and lipid modulating properties. However, the effects of flaxseed polysaccharide (FSP) on metabolic syndrome (MetS) and gut microbiota are still poorly understood. Here, we investigated the effects of FSP on lipid metabolism and gut microbiota in high-fat-diet-fed mice. FSP effectively reduced the serum fasting glucose, total triglyceride and total cholesterol levels. FSP consumption adipose accumulation impacted the gut microbiome at different taxonomic levels by increasing the proportions of beneficial Akkermansia and Bifidobacterium and decreasing the disease or obesity associated Oscillospira and Odoribacteraceae. These changes were highly correlated with the regulation of expression levels of lipid metabolism involved genes in the liver. The restoration of total SCFAs, especially propionate and butyrate might be an important strategy for mitigating HFD induced metabolic disorders. These findings suggest that FSP may use as a prebiotic for preventing MetS by modulating the gut microbiota. [ABSTRACT FROM AUTHOR]

• Flaxseed polyphenols exerted differential antioxidant effects in nanoemulsion. • SECO and flaxseed lignan macromolecule inhibited lipid oxidation in nanoemulsion. • The mechanism mainly related to the partitioning of polyphenols in nanoemulsion. • The glucoside in phenolic extracts decreased their association with lipid droplets. Recent studies have shown that the high susceptibility of flaxseed oil nanoemulsions to lipid oxidation limits their incorporation into functional foods and beverages. For this reason, the impact of various flaxseed phenolic extracts on the physical and oxidative stability of flaxseed oil nanoemulsions was investigated. Flaxseed lignan extract (FLE) and secoisolariciresinol (SECO) exhibited antioxidant activity whereas secoisolariciresinol diglucoside (SDG) and p -coumaric acid (CouA) exhibited prooxidant activity in the flaxseed oil nanoemulsions. The antioxidant potential of flaxseed phenolics in the nanoemulsions was as follows: SECO < CouA < SDG ≈ FLE. Moreover, the antioxidant/prooxidant activity of the phenolics was also related to their free radical scavenging activity and partitioning in the nanoemulsions. Our results suggested that both SECO and FLE were good plant-based antioxidants for improving the stability of flaxseed oil nanoemulsions. [ABSTRACT FROM AUTHOR]

Brain insulin resistance, induced by neuroinflammation and oxidative stress, contributes to neurodegeneration, that is, processes that are associated with Aβ accumulation and TAU hyperphosphorylation. Here, we tested the effect of chronic administration of melatonin (MLT) on brain insulin resistance and cognition deficits caused by a high‐fat diet (HFD) in aged rats. Results showed that MLT supplementation attenuated peripheral insulin resistance and lowered hippocampal oxidative stress levels. Activated microglia and astrocytes and hippocampal levels of TNF‐α in HFD‐fed rats were reduced by MLT treatment. Melatonin also prevented HFD‐induced increases in beta‐amyloid (Aβ) accumulation and TAU phosphorylation in the hippocampus. In addition, impairments of brain insulin signaling elicited by long‐term HFD were restored by MLT treatment, as confirmed by ex vivo insulin stimulation. Importantly, MLT reversed HFD‐induced cognitive decline as measured by a water maze test, normalized hippocampal LTP and restored CREB activity and BDNF levels as well as cholinergic neuronal activity in the hippocampus. Collectively, these findings indicate that MLT may exhibit substantial protective effects on cognition, via restoration of brain insulin signaling. [ABSTRACT FROM AUTHOR]