Structural identification and antioxidative activity evaluation of flaxseed lignan macromolecules: structure-activity correlation

Flaxseed lignan macromolecules(FLM)are a class of important secondary metabolites in fl axseed,which have been widely concerned due to their biological and pharmacological properties,especially for their antioxidative activity.For the composition and structure of FLM,our results confirmed that ferulic acid glycoside(FerAG)was directly ester-linked with herbacetin diglucoside(HDG)or pinoresinol diglucoside(PDG),which might determine the beginning of FLM biosynthesis.Additionally,p-coumaric acid glycoside(CouAG)might determine the end of chain extension during FLM synthesis in fl axseed.FLM exhibited higher antioxidative activity in polar systems,as shown by its superior 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical scavenging capacity compared to the 2,2’-azinobis(3-ehtylbenzothiazolin-6-sulfnic acid)(ABTS)cation free radical scavenging capacity in non-polar systems.Moreover,the antioxidative activity of FLM was found to be highly dependent on its composition and structure.In particular,it was positively correlated with the number of phenolic hydroxyl groups(longer FLM chains)and inversely related to the steric hindrance at the ends(lower levels of FerAG and CouAG).These fi ndings verifi ed the potential application of FLM in nonpolar systems,particularly in functional food emulsions。

Effect of defatted flaxseed gum powder addition on the quality of sesame paste

The study explored the influence of defatted flaxseed gum powder(DFGP) on the stability and quality of sesame paste by measuring and analyzing its composition, color, texture, particle size, centrifugal oil separation rate,rheological properties, and microstructure. The results showed that the moisture and polysaccharide content of sesame paste was increased as the DFGP increased. Additionally, the hardness, gumminess, and chewiness of the sesame paste was improved, while the presence of particles with small particle size(1–100 μm) was decreased.The rate of oil precipitation was reduced by 28.99% when the amount of DFGP was 6%. The sesame paste samples exhibited pseudoplastic behavior, demonstrating shear thinning. As the shear rate increased, the apparent viscosity of sesame paste gradually decreased. Both the storage modulus(G’) and the loss modulus(G’’) increased as the shear frequency increased. The microstructure observation revealed that protein and oil were evenly distributed in the sesame paste system, and the addition of DFGP enhanced the bonding between oil and protein.This study can provide valuable references for high-quality sesame paste products in the food industry.

Targeted microbiome metabolomics reveals flaxseed oil supplementation regulated the gut microbiota and farnesoid X receptor pathway in high-fat diet mice

Flaxseed oil(FSO)rich in n-3 polyunsaturated fatty acids(PUFAs)can protect against obesity and insulin resistance,but the underlying mechanism is unknown.An integrative multiomics of the microbiome and targeted metab olomics approach was performed to investigate the possible pathway for flaxseed oil supplementation on reducing serum total cholesterol,triglyceride and epididymal adipose in high-fat diet mice.FSO ameliorated the gut microbial dysbiosis by increasing the community diversity and the abundance of Clostridiales and Ruminococcaceae.These effects were associated with the regulation of bile acid(BAs)in the feces.FSO reduced the concentrations of conjugated BAs,such as cholic acid,tauro-α-murocholic acid,and tauro-ursodesoxycholic acid in feces,which in turn inhibit the intestinal farnesoid X receptor(FXR)-fibroblast growth factor(FGF)15 signaling pathway.Further analysis revealed that FSO activated FXR in the liver and regulated downstream gene expression(SHP,SREBP-1c,and CPT-1a),which promoted lipolysis and inhibited lipogenesis.The results of this study suggest that FSO modulates serum lipid concentrations by regulating the gut microbiota,FXR-FGF15 signaling and BA metabolism.

Elucidation of the structure, antioxidant, and interfacial properties of flaxseed proteins tailored by microwave treatment

The microwave treatment is commonly applied to flaxseed to release nutrients, inactivate enzymes, remove cyanogens,and intensify flavors. The current study aimed to explore the influences of microwave exposure on the antioxidant and interfacial properties of flaxseed protein isolates(FPI), focusing on the altering composition and molecular structure.The results showed that after microwave exposure(700 W, 1–5 min), more compact assembly of storage proteins and subsequent permeation by membrane fragments of oil bodies occurred for cold-pressing flaxseed flours. Moreover, the particle sizes of FPI was progressively reduced with the decrement ranged from 37.84 to 60.66%(P<0.05), whereas the zeta potential values initially decreased and then substantially recovered during 1–5 min of microwave exposure. The conformation unfolding, chain cross-linking, and depolymerization were sequentially induced for FPI based on the analysis of fluorescence emission spectra, secondary structure, and protein subunit profiles, thereby affecting the dispersion or aggregation properties between albumin and globulin fractions in FPI. Microwave exposure retained specific phenolic acids and superior in vitro antioxidant activities of FPI. The inferior gas–water interface absorption and the loose/porous assembly structure were observed for the foams prepared by FPI, concurrent with obviously shrinking foaming properties upon microwave exposure. Improving oil–water interface activities of FPI produced the emulsion droplets with descending sizes and dense interface coating, which were then mildly destabilized due to the lipid leakage and weakened rheological behavior with microwave exposure extended to 5 min. Our findings elucidated that microwave treatment could tailor the application functionality of protein fractions in flaxseed based on their in situ structural remodeling.

Physical and emulsifying properties of pea protein:influence of combined physical modification by flaxseed gum and ultrasonic treatment

This study characterized and compared the physical and emulsifying properties of pea protein(PP)and its modified proteins(ultrasound treated-PP(PPU),flaxseed gum(FG)treated PP(PPFG)and ultrasound treated-PPFG(PPFGU)).The results showed FG triggered the formation of loosely attached complex with PP via physical modification under gentle magnetic stirring at pH 7.0,while ultrasound played an important role in reducing protein size,increasing surface hydrophobicity and molecular fluidity onto oil-water interface.So ultrasound further enhanced the interaction of PP with FG,and produced the PPFGU complex with smaller droplet size,higherζ-potential and lower turbidity.Further,combination of FG and ultrasound improved the physical properties of PP with higher viscosity,stiffer gels(defined as higher elastic modulus),stronger hydrophobic properties,better thermal stability,and fast protein absorption rate.Therefore,the PPFGU coarse emulsion performed highest emulsifying activity index(EAI)and emulsion stability index(ESI)that the stabilized nanoemulsion obtained smallest droplet size,higherζ-potential,and longest storage stability.The combination of FG and ultrasonic treatment will be an effective approach to improving the emulsifying property and thermal stability of PP,which can be considered as a potential plant-based emulsifier applied in the food industry.

Role of flaxseed(Linum usitatissimum L.)in disease prevention and treatment

Seeds of flax or linseed(Linum usitatissimum L.)are important nutraceutical foods with antioxidant,anti-inflammatory,estrogenic,laxative,and antibacterial properties.Flaxseed oil and seeds are the richest vegetarian source of omega-3 fatty acids.Consumption of flaxseeds helps in prevention and control of cardiovascular disease,neurodegenerative disorders,obesity,diabetes mellitus,polycystic ovary syndrome,gout,liver and kidney dysfunction,oxidative stress-related diseases,post-menopausal symptoms,osteoporosis,irritable bowel syndrome,dry eye disease,cystic fibrosis,diarrhea,and cancer,particularly of the mammary and prostate gland cancer.Of late,flaxseed is gaining more importance not only because of its industrial values but also due to its nutraceutical and pharmaceutical properties.The literature review was performed using PubMed,Scopus,PubMed Central,Google Scholar,and Web of Science from 1995 onwards.Data was also obtained from websites/books/book chapters.

Antioxidant peptides encrypted in flaxseed proteome:An in silico assessment

Flaxseed proteins and antioxidant peptides(AP)encrypted in their sequences were analysed in silico with a range of bioinformatics tools to study their physicochemical properties,allergenicity,and toxicity.Nine proteases(digestive,plant and microbial sources)were assessed for their ability to release known APs from 23 mature flaxseed storage proteins using the BIOPEP database.The families of proteins identified were predominantly globulins,oleosins,and small amount of conlinin.Overall,253 APs were identified from these proteins.More peptides were released by enzymatic hydrolysis from the globulins than those from oleosins and conlinin.Compared with other enzymes studied,the plant proteases(papain,ficin,and bromelain)were found to be superior to releasing APs from the flaxseed proteins.Analysis of toxicity by ToxinPred showed that none of the peptides released was toxic.Most of the APs showed structural features that are important for antioxidation,including relatively low molecular weight(dipeptides and tripeptides only);amphipathic properties(hydrophobicity range of-0.5 to+0.5);relatively low Boman index(≤2);broad range of pI(3.7-10.8),and an abundance of antioxidant amino acid residues(e.g.glutamic acid and histidine).This study demonstrate the suitability of flaxseed proteins as a source of APs.

Milled flaxseed-added diets ameliorated hepatic inflammation by reducing gene expression of TLR4/NF-κB pathway and altered gut microbiota in STZ-induced type 1 diabetic mice

Flaxseed has displayed the potential beneficial as functional foods.However,most studies focused on effects of flaxseed extracts or ingredients in flaxseed.Besides,few studies showed that flaxseed extracts contributed to anti-type 1 diabetes(T1D),yet the underlying mechanism is still unknown.In the present study,16.7% of milled flaxseed(MF)-added diet was given to diabetic mice induced by streptozocin for 6 weeks.The results showed that MF feeding 1)slightly decreased blood glucose levels and improved the ability of glucose tolerance by oral glucose tolerance test,2)decreased liver tumor necrosis factor-αlevels and increased liver glycogen levels with significance via down-regulating TLR4/NF-κB pathways,3)and significantly altered some beneficial bacteria in gut microbiota.In conclusion,the present study showed that milled flaxseed showed the potential on anti-T1D through anti-inflammation via TLR4/NF-κB and altering the gut microbiota in STZ-induced diabetic mice.

Variation in the Content of Cyanogenic Glycosides in Flaxseed Meal from Twenty-One Varieties

Flaxseed meal from twenty-one varieties has been evaluated for content of cyanogenic glycosides (linamarin, linustatin and neolinustatin). Varieties belonging to three different groups of productive attitude (oil, fiber and intermediate) were considered. The total content of cyanogenic glycosides ranged from 0.74 to 1.60 g?Kg?1 CN?. As expected, linamarin was a minority component accounting for only 2% - 14% of total glycosides. Linustatin resulted statistically lower in the intermediate group than that in the other groups and, in particular, it was the lowest in the Festival variety. Neolinustatin resulted lower in the fiber group although the variety Ventimiglia (belonging to oil group) showed a negligible level of this compound. Neolinustatin was positively correlated to total cyanogenic glycosides (r = 0.709) and inversely correlated to linustatin (r = ?0.326). The variability observed in the content of the various forms of glycosides could be exploited in breeding programs to reduce the content of these toxic compounds in flaxseed meal.

Effect of Flaxseed on Bile Tolerances of <i>Lactobacillus acidophilus, Lactobacillus bulgaricus</i>, and <i>Streptococcus thermophilus</i>

Consumption of flaxseed provides health benefits. Bile tolerance allows survival of probiotics in the intestinal tract. The objective was to determine whether or not flaxseed enhances bile tolerance of Lactobacillus acidophilus (L. acidophilus) LA-K, Lactobacillus delbruekii ssp. bulgaricus (L. bulgaricus) LB-12, and Streptococcus salivarius ssp. thermophilus (S. thermophilus) ST-M5. Control and experimental (62 g flaxseed/L) broths containing 0.3% oxgall were prepared for each culture, sterilized, cooled, inoculated, and plated for 8 h. Growth of each microorganism in both the control and experimental broths was evaluated by the slope of the regression line of its log count versus time after inoculation. Flaxseed significantly enhanced growth of L. acidophilus but not L. bulgaricus and S. thermophilus over 8 h compared to its corresponding control. Therefore, flaxseed improved the bile tolerance of L. acidophilus but not of S. thermophilus and L. bulgaricus.

Impact of feeding flaxseed and microalgal residue on omega-3 fatty acids enrichment in hen eggs

To investigate the impact of dietary supplementation of different omega-3 polyunsaturated fatty acids (n-3 PUFAs) resources on PUFAs enrichment in hen eggs, two supplemental materials, flaxseed and oil-extracted microalgal residue of heterotrophic Schizochytrium, were added to the diet of laying hens in 3 groups. Results showed that supplementation with flaxseed and Schizochytrium residue gave rise to the increased, but different n-3 PUFAs levels in egg yolk, mainly α-linolenic acid (ALA) and docosahexaenoic acid (DHA). The ratio of n-6/n-3 PUFAs was reduced in all groups. After 14 days feeding of supplied PUFAs resources, n-3 PUFAs contents reached a plateau, and then remained constant during further supplementation in 3 experimental groups. Both the highest ALA level and DHA level were achieved in flaxseed group and microalgae group, reaching up to 353.69 (±68.15) mg/egg and 301.41 (± 26.76) mg/egg respectively. Moreover, the n-3 PUFAs enrichment efficiency was relatively low in flaxseed group when compared to other 2 groups. Laying rates of hens before entering peak production period could be improved by adding flaxseed but was not obviously affected by Schizochytrium residue. The egg weight, on the other hand, had no relationship with dietary supplementation. Thus, supplementation of flaxseed or Schizochytrium residue into standard feed offers an alternative choice for the production of n-3 PUFAs enriched eggs.

Flaxseed Lignans Promoted the Growth of Skeletal Muscle in Male Rats and Its Possible Mechanism

This study was aimed to determine whether flaxseed lignans could affect the growth of skeletal muscle in male animals and its possible mechanisms. The impact of flaxseed lignans on the skeletal muscle in male rats was determined in vivo. Flaxseed lignans （50 ppm） and daidzein （5 ppm） were added into the basal diets, respectively. The concentrations of serum lignans and daidzein were measured by high performance liquid chromatography （HPLC）, and the serum growth hormone and testosterone （T） levels were analyzed by radioimmunoassay （RIA）, and the expression of estrogen receptor β （ER β） in the soleus muscle and hypothalamus were determined by reverse-transcription polymerase chain reaction （RT-PCR）. Flaxseed lignans and daidzein could significantly improve the feed efficiency and facilitate the weight gain of the femoral muscle in male rats. The ratio of RNA to DNA in the muscles and serum T levels was remarkably increased, whereas, the urea nitrogen concentrations were significantly decreased by flaxseed lignan and/or its metabolites and daidzein. Meanwhile, the expression of ER β in soleus muscle and hypothalamus were both upgraded by the two phytoestrogens. Flaxseed lignan promoted the growth of male rats, and it might be by regulating serum T levels by binding to ER β in the hypothalamus. In turn, it depressed the catabolism of protein and promoted the hypertrophy of skeletal muscle ceils.

Effect of flaxseed supplementation on metabolic state,endocrine profiles,body composition and reproductive performance of sows

Objective:To assess the effect of flaxseed supplementation on metabolic profile,endocrine concentrations,non-esterified fatty acids(NEFA),body composition variables,and reproductive performance of sows.Methods:All the 21 crossbred Large White Yorkshire sows were considered in the study period starting at day 1 of current farrowing when the feeding of specific supplemental ration was started until the day of subsequent farrowing(days 150-155)and were equally allocated into three groups.Group 1 served as the control group and followed their normal feeding schedule.Group 2 and group 3,in addition to their normal feeding schedule,were supplemented with flaxseed at a rate of 0.5%and 1.0%of the dry matter,respectively.Blood samples were collected 15 days prior to farrowing,on the day of farrowing(day 0),at weekly intervals until day 28 of lactation and at monthly intervals during gestation to harvest the plasma.Plasma was used to assess the metabolic and endocrine status of sows.Body weight of each sow and individual birth weight of all piglets born were measured.Results:Flaxseed supplementation led to decrease in plasma cholesterol and triglyceride levels in the supplemented groups than in the control group(P<0.05).Plasma estradiol-17βlevel was higher in group 2 than that in group 1 and 3 on day 90 of the gestation period(P<0.05).The mean plasma level of insulin-like growth factor 1 was higher in group 3 than that in group 1 and 2 both in late lactation(day 28)as well as in early gestation(day 30)(P<0.05).Plasma NEFA and weight gain were greater in sows of group 2 and 3 compared to those fed with the normal control diets(P<0.05).The proportion of pregnant sows relative to sows bred was 100.0%in group 2 and 3 and 85.7%in the control group.Piglet mortality was lower in group 2 and 3 compared to group 1(P>0.05).Conclusions:Flaxseed improves endocrine profiles,NEFA concentrations and body weight,resulting in better pregnancy rate and litter size.

Rheological Properties of Barley and Flaxseed Composites

The newly developed barley-flaxseed composites were unique because barley provides the soluble fiber β-glucan that is beneficial for improving food texture and preventing coronary heart disease along with the health benefits of omega-3 polyunsaturated fatty acids (w-3 PUFAs) of flaxseed. The new composites of barley with flaxseeds were prepared using prowashonupana, a barley variety containing high β-glucan content, with 10, 20, and 50% flaxseed for enhancing health benefits of functional food. Besides the nutritional aspects of barley-flaxseed composites, they have improved water holding capacities, texture, and useful pasting and viscoelastic qualities measured using a Rapid Visco Analyzer (RVA) followed by an advanced rheometer. The pasting and rheological properties of the barley flour were not greatly influenced by 10% ground flaxseed replacements but showed differences at the 50% replacement level. Shear thinning properties were observed for all the composites. These functional composites could be valuable and applicable for developing new functional food products with health benefits of decreasing heart problems, diabetes, and obesity along with providing desirable texture.

Incorporation of Omega-3 on an Extruded Snack with Golden Flaxseed

This study evaluates the incorporation of alpha-linolenic acid （LNA, 18：3n-3） through the golden flaxseed in snacks＇ formulations with and without seasoning. Snacks with different formulations presented significant differences （P 〈 0.05） in their proximate composition, mainly for total lipids and moisture content. Regarding the fatty acids profile, six different fatty acids were found： 16：0, 18：0, 18：1n-9, 18：1n-7, 18：2n-6 （LA） and 18：3n-3. The majority fatty acid was 18：2n-6 （LA） due to the predominance of corn in the products formulation. The incorporation of 18：3n-3 was observed, and this fatty acid was not affected by the extrusion temperature during the processing or the storage time. The results of sensory evaluation indicated that the product developed with addition of golden flaxseed had mild acceptance among the panelists. Thus, it was concluded that the addition of flaxseed is feasible for the nutritional enrichment of corn snacks.

Dietary flaxseed oil regulate lipid metabolism associated with modulation of gut microbiota in high-fat-diet fed mice

Accumulating data suggest that consuming dietary flaxseed oil(FSO)was a potential strategy for treating diet-induced lipid metabolism disorder(LMD).Effects of FSO on high-fat-diet(HFD)induced LMD and gut microbiota were studied in C57/BL6J mice.Results showed that FSO remarkably suppressed body weight gain induced by HFD and also attenuated LMD by decreasing levels of total cholesterol(TC),total triglyceride(TG),lowdensity lipoprotein cholesterol(LDL-C),non-esterified fatty acid(NEFA)and fasting bloodglucose(FBG)in serum.FSO treatment modulated mRNA expression level of genes associated with glucose and lipid metabolism.It regulated gut microbiome at different taxonomic levels by increasing proportions of beneficial Alistipes,Anaeroplasma,Bifidobacterium and inhibiting the growth of insulin resistance or obesity-associated bacteria such as Adlercreutzia,Dorea and Sporosarcina,compared with HFD group.Spearman's correlation analysis suggested that modulation of gut microbiota by FSO were closely related with LMD parameters.These findings might help us to better understand FSO impact on human health.

Nutritional composition and functions of flaxseed ( Linum usitatissimum linn .)

Diet and nourishment are the foundation of living wellbeing and development.With advancements in clinical nutrition and increasingly growing awareness of nutritional principles of eatables,nutraceuticals have emerged as an important part of the healthcare system.India offers a variety of natural plant medicines that have high promise and pharmacological activity.Linum usitatissimum linn is an annual plant used for the treatment of many illnesses in numerous traditional medicines.Flaxseed is an upright,thin,and fibrous cold,temperate plant.The seed is reported to have cardio vascular,antidiabetic,antibacterial,antioxidant,estrogenic effects,etc.It has the highest source of Alpha-linolenic acid(ALA),dietary fiber,omega-3 fatty acid,lignan mostly Secoisolariciresinol diglucoside(SDG),protein,and soluble mucilage,all of which have benefits for the overall management in the hea lth sector.Flaxseed is a major part of various regimens of Ayurveda.This mini-review outlines the nutritional composition of flaxseed.

Heat Treatment and Thirty-Day Storage Period Do Not Affect the Stability of Omega-3 Fatty Acid in Brown Flaxseed(Linum Usitatissimum)Whole Flour

This study was conducted to verify if the processing and storage of brown flaxseed whole flour result in loss of func-tional properties, such as reduced linolenic acid content, increased lipid peroxidation and sensory changes. The flours were obtained from seeds dried by heat treatment in oven at 150?C, for 15 minutes and subsequent grinding to obtain flour with a particle size of 20 mesh. Meal samples, with and without synthetic antioxidants (BHA and BHT combined, at 100 ppm each), were stored for a thirty-day period, under similar conditions to those used commercially. The linolenic acid content was quantified by gas chromatography. Lipid peroxidation was analyzed by thiobarbituric acid reactive substance assay. Color and flavor were evaluated by sensory tests. The linolenic acid content and lipid peroxidation did not significantly change after processing or during storage. Fluctuations in color and flavor occurred during storage, but at the end of 30 days, only the heat treatment presented negative effect (p < 0.05) on the parameter color. Heat treatment and thirty-day storage period do not change the stability of n-3 fatty acid in brown flaxseed whole flour.

Characterization of Flaxseed Oil for Nuclear Magnetic Resonance and Its Encapsulation

Flaxseed (Linum usitatissimum L.) is one of the oldest crops known by humans and it has been used in numerous applications, such as in the textile industry, feed formulation, fertilizers, and paper industry. However, nowadays these seeds have won an important highlight for human consumption due to their active ingredients that make them an excellent functional food. Thus, this study aimed to extract flaxseed oil, an oil rich in omega 3 and 6, characterize it by using nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR) and then encapsulate this oil in polycaprolactone (PCL) on the micro scale, using the nanoprecipitation technique and subsequently freeze-drying. To determine the mean diameter, the dynamic light scattering technique (DLS) was used, and to verify whether there was encapsulation, the pulse sequence MSE-FID, an NMR sequence in the time domain, was also used. In addition to the previously mentioned techniques, X-ray diffraction (XRD) was also employed. Flaxseed flour was also analyzed by time-domain NMR and FTIR. The results obtained by NMR show that the oil consists of fatty acid esters in the form of triglycerides in which there is the presence of esters of α-linolenic and linoleic acids, respectively ALA and LA, according to the literature. Regarding the material after encapsulation, it presented a mean diameter of 445.2 ± 41 nm and PDI of 0.674 ± 0.064, therefore classified as microparticles. Finally, using the sequence MSE-FID and the FTIR, it can be concluded that there has been the microencapsulation of flaxseed oil in the particles formed.

Protective Role of Golden Flaxseed (Linum usitatissimum L.) Against Oxidative Damage in Lipids and Proteins of Healthy Volunteers

Flaxseed (Linum usitatissimum L.) is composed mainly of bioactive components such as polyphenols, polyunsaturated fatty acids, fiber and lignans. Flaxseed can be found in different presentation forms (grain or flour) and varieties (brown or golden);however, questions have arisen as to whether the presentation form and/or variety may influence the health effects. The objective of this study was to evaluate the effects on blood pressure, anthropometric and oxidative parameters in healthy human volunteers. All subjects received 40 gram aliquots of flaxseed and were instructed to consume them in their entirety mixed with water in the morning for a period of 14 days. Oxidative parameters showed significant reductions (p < 0.05) in oxidative damage to lipids and proteins via dietary intervention with golden flaxseed grains. There were no significant differences in anthropometric parameters, blood pressure, DNA damage and micronuclei frequency after 14-day supplementation. This research indicates that golden flaxseed grains can be a valuable adjunct for disease prevention and protecting the organism against oxidative damage.