Fatty Acid Release and Gastrointestinal Oxidation Status: Different Methods of Processing Flaxseed.

Flaxseed has been recognized as a superfood worldwide due to its abundance of diverse functional phytochemicals and nutrients. Various studies have shown that flaxseed consumption is beneficial to human health, though methods of processing flaxseed may significantly affect the absorption and metabolism of its bioactive components. Hence, flaxseed was subjected to various processing methods including microwaving treatment, microwave-coupled dry milling, microwave-coupled wet milling, and high-pressure homogenization. In vitro digestion experiments were conducted to assess the impact of these processing techniques on the potential gastrointestinal fate of flaxseed oil. Even though more lipids were released by the flaxseed at the beginning of digestion after it was microwaved and dry-milled, the full digestion of flaxseed oil was still restricted in the intestine. In contrast, oil droplets were more evenly distributed in wet-milled flaxseed milk, and there was a greater release of fatty acids during simulated digestion (7.33 ± 0.21 µmol/mL). Interestingly, wet-milled flaxseed milk showed higher oxidative stability compared with flaxseed powder during digestion despite the larger specific surface area of its oil droplets. This study might provide insight into the choice of flaxseed processing technology for better nutrient delivery efficiency.

Recent advances in understanding the interfacial activity of antioxidants in association colloids in bulk oil.

The chemical stability of edible oils rich in polyunsaturated fatty acids (PUFAs) is a major challenge within the food and supplement industries, as lipid oxidation reduces oil quality and safety. Despite appearing homogeneous to the human eye, bulk oils are actually multiphase heterogeneous systems at the nanoscale level. Association colloids, such as reverse micelles, are spontaneously formed within bulk oils due to the self-assembly of amphiphilic molecules that are present, like phospholipids, free fatty acids, and/or surfactants. In bulk oil, lipid oxidation often occurs at the oil-water interface of these association colloids because this is where different reactants accumulate, such as PUFAs, hydroperoxides, transition metals, and antioxidants. Consequently, the efficiency of antioxidants in bulk oils is governed by their chemical reactivity, but also by their ability to be located close to the site of oxidation. This review describes the impact of minor constituents in bulk oils on the nature of the association colloids formed. And then the formation of mixed reverse micelles (LOOH, (co)surfactants, or antioxidations) during the peroxidation of bulk oils, as well as changes in their composition and structure over time are also discussed. The critical importance of selecting appropriate antioxidants and surfactants for the changes of interface and colloid, as well as the inhibition of lipid oxidation is emphasized. The knowledge presented in this review article may facilitate the design of bulk oil products with improved resistance to oxidation, thereby reducing food waste and improving food quality and safety.

Regulation of interfacial mechanics of soy protein via co-extraction with flaxseed protein for efficient fabrication of foams and emulsions.

Enrichment of plant proteins with functionality is of great importance for expanding their application in food formulations. This study proposed an innovation to co-enrich soy protein and flaxseed protein to act as efficient interfacial stabilizers for generating foams and emulsions. The structure, interfacial properties, and functionalities of the soy protein-flaxseed protein natural nanoparticles (SFNPs) obtained by alkali extraction-isoelectric precipitation (AE) and salt extraction-dialysis (SE) methods were investigated. Overall, the foamability of AE-SFNPs (194.67 %) was 1.45-fold that of SE-SFNPs, due to their more flexible structure, smaller particle size, and suitable surface wettability, promoting diffusion and adsorption at the air-water interface. AE-SFNPs showed higher emulsion stability (140.89 min), probably because the adsorbed AE-SFNPs with smaller size displayed soft particle-like properties and stronger interfacial flexibility, and therefore could densely and evenly arrange at the interface, facilitating the formation of a stiff and solid-like interfacial layer, beneficial for more stable emulsion formation. The findings may innovatively expand the applications of SFNPs as food ingredients.

Effect of Different Temperatures on the Storage Stability of Flaxseed Milk.

In this study, the physical and oxidative stability of flaxseed milk without food additives at different temperatures (25 °C and 37 °C) was assessed. Over in 206 days in storage, the particle size, Turbiscan stability index (TSI), centrifugal sedimentation rate, and primary and secondary oxidation products of flaxseed milk increased, viscosity decreased, and the absolute value of the potential first decreased and then increased. These phenomena indicated a gradual decrease in the physical stability of flaxseed milk, accompanied by drastic oxidative changes. The antioxidant capacity of flaxseed milk was related to the location of the physical distribution of flaxseed lignin, which was more effective in the aqueous phase compared to the non-aqueous phase. Interestingly, after 171 days in storage at 37 °C, the particle size of flaxseed milk was approximately doubled (6.98 µm → 15.27 µm) and the absolute value of the potential reached its lowest point (-13.49 mV), when the content of primary oxidation products reached its maximum (8.29 mmol/kg oil). The results showed that temperature had a significant effect on the stability of flaxseed milk and that stability decreased with increasing temperature and shortened shelf life. This work provides a theoretical basis for elucidating the stabilization-destabilization mechanism of flaxseed milk.

Preparation of polysaccharide-based nanoparticles by chitosan and flaxseed gum polyelectrolyte complexation as carriers for bighead carp (Aristichthys nobilis) peptide delivery.

Polysaccharide-based nanoparticles formed by the polyelectrolyte complexation between chitosan (CS) and flaxseed gum (FG) was developed in this work, and it was further used as a carrier for bighead carp peptide (BCP) delivery. The CS molecular weight (MW) of 50 kDa and CS/FG mass ratio of 1:2 at pH 3.5 were optimal conditions for the NP preparation, with the minimum particle size (∼155.1 nm) and the maximum BCP encapsulation efficiency (60.3 %). The BCP-loaded CS/FG NPs exhibited the smallest particle size (175.8 nm). Both CS/FG NPs and CS/FG-BCP NPs exhibited roughly uniform spherical shape. FT-IR spectra confirmed the existence of hydrogen bonds and electrostatic interactions in the nanoparticles. The BCP-loaded NPs displayed a higher thermal stability than BCP. Moreover, the release of BCP was controllable and dose-dependent, following a first-order kinetics model. These findings suggested that our CS/FG NPs are a promising carrier for bioactive peptide delivery.

Inhibition of advance glycation end products formation, gastrointestinal digestion, absorption and toxicity: A comprehensive review.

Advanced glycation end-products (AGEs) are the final products of the non-enzymatic interaction between reducing sugars and amino groups in proteins, lipids and nucleic acids. In numerous diseases, such as diabetes, neuropathy, atherosclerosis, aging, nephropathy, retinopathy, and chronic renal illness, accumulation of AGEs has been proposed as a pathogenic mechanism of inflammation, oxidative stress, and structural tissue damage leading to chronic vascular issues. Current studies on the inhibition of AGEs mainly focused on food processing. However, there are few studies on the inhibition of AGEs during digestion, absorption and metabolism although there are still plenty of AGEs in our body with our daily diet. This review comprehensively expounded AGEs inhibition mechanism based on the whole process of digestion, absorption and metabolism by polyphenols, amino acids, hydrophilic colloid, carnosine and other new anti-glycation agents. Our study will provide a ground-breaking perspective on mediation or inhibition AGEs.

The physicochemical stability and in vivo gastrointestinal digestion of flaxseed milk: Implication of microwave on flaxseed.

The current study was to investigate how microwave on flaxseed affected the physicochemical stability and gastrointestinal digestion of oil bodies (OBs) in flaxseed milk. Flaxseed was subjected to moisture adjustment (30-35 wt%, 24 h), and microwave exposure (0-5 min, 700  W). Microwave treatment slightly weakened the physical stability of flaxseed milk indicated by Turbiscan Stability Index, but there were no visual phase separation during 21 days of storage at 4 °C. Upon microwave treatment, OBs experienced the layer-by-layer encapsulation into loose interface embedding by storage protein-gum polysaccharide complex from bulk phase, resulting in lower viscoelasticity of flaxseed milk. The OBs underwent earlier interface collapse and lipolysis during gastrointestinal digestion, followed by synergistic micellar absorption, faster chylomicrons transport within enterocytes of rats fed flaxseed milk. The accumulation of α-linolenic acid and synergistic conversion into docosapentaenoic and docosahexanoic acids in jejunum tissue were achieved accompanied by the interface remodeling of OBs in flaxseed milk.

Composition, processing, and quality control of whole flaxseed products used to fortify foods.

Whole flaxseed (flour) as a good source of omega-3 fatty acid and phytochemicals with excellent nutritional and functional attributes has been used to enrich foods for health promotion and disease prevention. However, several limitations and contemporary challenges still impact the development of whole flaxseed (flour)-enriched products on the global market, such as naturally occurring antinutritional factors and entrapment of nutrients within food matrix. Whole flaxseed (flour) with different existing forms could variably alter the techno-functional performance of food matrix, and ultimately affect the edible qualities of fortified food products. The potential interaction mechanism between the subject and object components in fortified products has not been elucidated yet. Hence, in this paper, the physical structure and component changes of flaxseed (flour) by pretreatments coupled with their potential influences on the edible qualities of multiple fortified food products were summarized and analyzed. In addition, several typical food products, including baked, noodle, and dairy products were preferentially selected to investigate the potential influencing mechanisms of flaxseed (flour) on different substrate components. In particular, the altered balance between water absorption of flaxseed protein/gum polysaccharides and the interruption of gluten network, lipid lubrication, lipid-amylose complexes, syneresis, and so forth, were thoroughly elucidated. The overall impact of incorporating whole flaxseed (flour) on the quality and nutritional attributes of fortified food products, coupled with the possible solutions against negative influences are aimed. This paper could provide useful information for expanding the application of whole flaxseed (flour) based on the optimal edible and nutritional properties of fortified food products.

Fabrication and Characterization of Botanical-Based Double-Layered Emulsion: Protection of DHA and Astaxanthin Based on Interface Remodeling.

Both DHA and astaxanthin, with multiple conjugated double bonds, are considered as health-promoting molecules. However, their utilizations into food systems are restricted due to their poor water solubility and high oxidizability, plus their certain off-smell. In this study, the interactions between perilla protein isolate (PPI) and flaxseed gum (FG) were firstly investigated using multiple spectroscopies, suggesting that hydrophobic, electrostatic force and hydrogen bonds played important roles. Additionally, double-layer emulsion was constructed by layer-by-layer deposition technology and exhibited preferable effects on masking the fishy smell of algae oil. Calcium ions also showed an improving effect on the elasticity modulus of O/W emulsions and was managed to significantly protect the stability of co-delivered astaxanthin and DHA, without additional antioxidants during storage for 21 days. The vegan system produced in this study may, therefore, be suitable for effective delivery of both ω-3 fatty acid and carotenoids for their further incorporation into food systems, such as plant-based yoghourt, etc.

DHA Ameliorates Cognitive Ability, Reduces Amyloid Deposition, and Nerve Fiber Production in Alzheimer's Disease.

Background: The etiology of Alzheimer's disease (AD) is very complex. Docosahexaenoic acid (DHA) is important in cognitive ability and nervous system development. A limited number of studies have evaluated the efficacy of DHA in the treatment of AD. Introduction: We detected neurofibrillary tangles (NFT) in the hippocampus and cortex of transgenic mice brain through silver glycine staining. We determined the activity of neurons by staining Nissl bodies, used liquid NMR to detect metabolites in the brain, and functional magnetic resonance imaging results to observe the connection signal value between brain regions. Materials and Methods: We fed 3-month-old APP/PS1 double transgenic mice with DHA mixed feeds for 4 months to assess the effects of DHA on cognitive ability in AD mice through the Morris water maze and open field tests. To evaluate its effects with AD pathology, continuous feeding was done until the mice reached 9 months of age. Results: Compared to AD mice, escape latency significantly decreased on the fifth day while swimming speed, target quadrant stay time, and the crossing number of platforms increased by varying degrees after DHA treatment. Brain tissue section staining revealed that DHA significantly reduced Aß and nerve fibers in the brain of AD mice. Conclusion: DHA significantly reduced the deposition of Aß in the brain and inhibited the production of nerve fibers, thereby increasing cognitive abilities in AD mice. In addition, DHA suppressed blood lipid levels, and restored uric acid and urea levels, implying that DHA is a potential therapeutic option for early AD.

Pharmacodynamics and Pharmacokinetics of HSK3486, a Novel 2,6-Disubstituted Phenol Derivative as a General Anesthetic.

Background: The purpose of this study was to characterize the novel sedative/hypnotic agent HSK3486, a 2,6-disubstituted alkylphenol analogue. Methods: The mechanism of action of HSK3486 was studied in competitive binding assays and whole-cell patch clamp assays. HSK3486 was administered by bolus intravenous injection to dogs and rats, and the loss of righting reflex as well as effects on the cardiovascular and respiratory systems were assessed. The in vitro metabolism of HSK3486 was analyzed by CYP450 genotyping and enzyme inhibition. Results: HSK3486 competed with t-butylbicycloorthobenzoate (TBOB) and t-butylbicyclophosphorothionate (TBPS) for binding to the gamma-aminobutyric acid type A (GABAA) receptor. HSK3486 potentiated GABA-evoked chloride currents at lower concentrations while activating GABAA receptor at higher concentrations. HSK3486 induced hypnosis in rats and dogs, and had a higher therapeutic index than propofol in rats. The hypnotic potency of HSK3486 was approximately 4-5 fold higher than that of propofol. HSK3486 exerted minimal effects on the cardiovascular system. Conclusions: HSK3486 is a positive allosteric regulator and direct agonist of GABAA receptor. It has a promising sedative/hypnotic effect and good in vivo pharmacokinetic properties, which justify further studies towards its clinical application.

Free-Radical-Mediated Formation Mechanism of Polar Polymeric Triglycerides in Vegetable Oil Studied by Electron Spin Resonance and High-Performance Liquid Chromatography.

The free-radical-mediated formation mechanism of polar polymeric triglycerides (TAGs) was derived based on the formation of lipid-derived radicals and the degradation of TAGs in palm oil (PO), rapeseed oil (RO), and sunflower oil (SO). The experimental spectra were simulated by alkoxyl, alkyl, and 5-dimethyl-1-pyrroline N-oxide (DMPO)-oxidized adducts. DMPO-oxidized adducts were the main radical adducts in the initial stage. Then, alkyl radical adducts became the dominating radical adducts after 12 min in PO and RO. The intensity of alkyl radical adducts was the highest in SO. Therefore, based on the bimolecular reaction, polar polymeric TAGs were mainly bonded by -C-O-O-C- in the initial stage and then by -C-C- and -C-O-C- after 30 min. Besides, according to the correlation analysis between the amounts of polar polymeric TAGs and the degradation of TAGs, the main structures of polar polymeric TAGs in PO, RO, and SO were POL-LOP, POL-OOP, and POO-OOP; OLL-LnLO, OLLn-OLnO, OOO-OLO, and OLLn-OOO; and LLL-LLO, LLL-LLL, and OLL-LLO, respectively.

Effect of different structural flaxseed lignans on the stability of flaxseed oil-in-water emulsion: An interfacial perspective.

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.

Effect of sesamol on the physical and chemical stability of plant-based flaxseed oil-in-water emulsions stabilized by proteins or phospholipids.

Plant-based polyphenols are increasingly being explored as functional ingredients in emulsified food systems. In this study, the effects of sesamol on the physical and chemical stability of flaxseed oil-in-water emulsions stabilized by either phospholipids (sunflower) or proteins (whey or pea) were investigated. In the absence of sesamol, the protein-based emulsions displayed better physical stability than the phospholipid-based ones, which was related to their smaller particle diameter and higher particle charge. For the phospholipid-based emulsions, sesamol addition did not improve their physical stability, but it did inhibit lipid oxidation. In particular, it decreased the formation of secondary oxidation products, with a 65% reduction in TBAR formation compared to the control after 8 days of storage. For the protein-based emulsions, sesamol addition reduced particle aggregation and inhibited lipid oxidation, reducing the secondary oxidation products by around 85% after 19 days of storage. The inhibitory efficiency of sesamol in the pea protein-based emulsions was comparable to that in the whey protein-based ones. The effects of sesamol on the physical and chemical stability of the emulsions were related to its partitioning between the oil, water, and interfacial layers. This study suggests that adding sesamol to plant-based emulsions may improve their physical and chemical stability, thereby extending their shelf life.

Fabrication and characterization of whey protein isolates- lotus seedpod proanthocyanin conjugate: Its potential application in oxidizable emulsions.

Emulsified ω-3 polyunsaturated fatty acid have expanding application in different food matrix with improved water solubility while still prone to oxidation. Lotus seedpod proanthocyanidin (LSPC) was grafted to whey protein isolate (WPI) to create nature-derived antioxidant emulsifiers. 1HNMR, SDS-PAGE and multiple spectrometry showed that the structure of protein was changed after grafting. DPPH and FRAP measurements showed that WPI-LSPC conjugate (90.53 ± 1.48% of DPPH scavenging, 691.85 ± 4.54 µg/mL for FRAP assay) possessed a much better antioxidant ability than WPI (17.06 ± 3.34% of DPPH scavenging, 10.43 ± 0.26 µg/mL for FRAP assay). Ultrasonic emulsification and DSC experiments showed that WPI-LSPC conjugate were more effective at forming and stabilizing the flaxseed oil emulsions than pure WPI, with higher thermostability. Likewise, low levels of primary and secondary oxidation products were formed for the conjugate than the pure protein in O/W systems after storage, again suggesting WPI-LSPC could be used as fine antioxidant emulsifiers in oxidizing delivery systems.

Oligomeric Procyanidin Nanoliposomes Prevent Melanogenesis and UV Radiation-Induced Skin Epithelial Cell (HFF-1) Damage.

The potential protective effect of nanoliposomes loaded with lotus seedpod oligomeric procyanidin (LSOPC) against melanogenesis and skin damaging was investigated. Fluorescence spectroscopy showed that, after encapsulation, the LSOPC-nanoliposomes still possessed strong inhibitory effects against melanogenesis, reducing the activity of both monophenolase and diphenolase. Molecular docking indicated that LSOPC could generate intense interactive configuration with tyrosinase through arene-H, arene-arene, and hydrophobic interaction. An ultraviolet radiated cell-culture model (human foreskin fibroblast cell (HFF-1)) was used to determine the protective effects of the LSOPC-nanoliposomes against skin aging and damage. Results showed that LSOPC-nanoliposomes exerted the highest protective effects against both ultraviolet B (UVB) and ultraviolet A (UVA) irradiation groups compared with non-encapsulated LSOPC and a control (vitamin C). Superoxide dismutase (SOD) and malonaldehyde (MDA) assays demonstrated the protection mechanism may be related to the anti-photooxidation activity of the procyanidin. Furthermore, a hydroxyproline assay suggested that the LSOPC-nanoliposomes had a strong protective effect against collagen degradation and/or synthesis after UVA irradiation.

Flavonoid compounds and antibacterial mechanisms of different parts of white guava (Psidium guajava L. cv. Pearl).

The flavonoid compositions, extracted from leaves, peel and flesh of white guava (Psidium guajava L. cv. Pearl), were identified and quantified by UPLC-ESI-QTOF-MS, HPLC-ESI-MS/MS and HPLC. The main components of three extracts all were quercetin-glycosides, but the proportion and content of quercetin-hexoside and quercetin-pentoside in each extract were different. Based on the measurements of MIC, MBC value and time killing curve, it emerged that 3 flavonoid extracts of white guava had good antibacterial effects on four pathogenic bacteria. White guava leaves flavonoids (WGLF) concentrations of 5.00 mg/mL and 0.625 mg/mL could change the micro-morphology of Escherichia coli and Staphylococcus aureus. It suggested that the antibacterial mechanism of WGLF on gram-positive and gram-negative bacteria was to destroy the structure and function of the cell membrane. It is indicated that the flavonoid extracts from white guava is a potential natural antimicrobial agent.

Lotus seedpod proanthocyanidin-whey protein complexes: Impact on physical and chemical stability of ß-carotene-nanoemulsions.

The impact of lotus seedpod proanthocyanidin (LSPC) on the functional properties of ß-carotene-loaded whey-protein stabilized nanoemulsions was investigated. LSPC was selected because it is known to exhibit strong antioxidant activity, as well as having various health benefits. Physically stable nanoemulsions containing small anionic droplets (d < 0.15 µm; ζ = -27 mV) could be formed at pH 6.5 using whey protein-LSPC complexes as natural emulsifiers. The physical and chemical stabilities of the nanoemulsions were then measured when they were incubated at different pH values. LSPC addition promoted droplet aggregation at pH 4, but not at pH 3, 6.5, or 8, which was mainly attributed to its ability to reduce the electrostatic repulsion between the lipid droplets at pH 4. LSPC was shown to have stronger antioxidant activity than catechin and epicatechin. Our results show that the chemical stability of ß-carotene nanoemulsions could be considerably improved by adding LSPC. We believe that LSPC-whey protein complexes can be used as effective emulsifiers and antioxidants in nutraceutical-loaded nanoemulsions, which may be useful for developing more efficacious functional foods and beverages.

Beyond Altruism: Framing Organ Donation in a 19-year Review of Chinese News Coverage.

Despite a significant legal transformation of the organ donation system in China, the public's willingness to become organ donors remains low. This study provides the first empirical examination of how Chinese newspaper coverage reflects the complex interplay among multifaceted factors associated with the stagnant donation rate. Using framing as the primary theoretical lens, we analyzed 923 organ donation newspaper articles from 2000 to 2018 in terms of topics, facilitators and barriers, valence, and policy development. The three most common topics emphasized were: a new official information release regarding organ donation promotion; the challenges of promoting organ donation in social, cultural, and legal contexts; and the positive emotional appeals of organ donors, coordinators, and transplant surgeons. Findings suggest that the values that facilitators of and barriers to organ donation represent can be culturally favored but in conflict with each other. Sharp increases in the presence of policy development framing are associated with the official announcements of new legislation. A better understanding of trending topics and interacting influence from facilitators and barriers is imperative for developing culturally tailored messages to raise awareness about organ donation promotion.

Potential TSPO Ligand and Photooxidation Quencher Isorenieratene from Arctic Ocean Rhodococcus sp. B7740.

Due to its special aromatic structure, isorenieratene is thought to be an active natural antioxidant and photo/UV damage inhibitor. In this work, isorenieratene that was extracted from Rhodococcus sp. B7740 isolated from the Arctic Ocean, showed excellent scavenging ability of both singlet oxygen and hydroxyl radical in the UVB-induced auto-oxidation process using the EPR method. Within an ARPE-19 cell model damaged by UVB radiation, isorenieratene showed fine protective effects (1.13 ± 0.03 fold) compared with macular xanthophylls (MXs) through upregulating of tspo. The molecular docking was firstly performed to investigate the interaction of isorenieratene with TSPO as a special ligand. Results showed isorenieratene might form a better binding conformation (S-score -8.5438) than MXs and indicate that isorenieratene not only can function as a direct antioxidant but also activate tspo in ARPE-19 cells. Thus, isorenieratene might ease the UV-related damages including age-related macular degeneration (AMD).