Spatial metabolome of biosynthesis and metabolism in Cyclocarya paliurus leaves.

A large number of plant metabolites were discovered, but their biosynthetic and metabolic pathways are still largely unknown. However, the spatial distribution of metabolites and their changes in metabolic pathways can be supplemented by mass spectrometry imaging (MSI) techniques. For this purpose, the combination of desorption electrospray ionization (DESI)-MSI and non-targeted metabolomics was used to obtain the spatial distribution information of metabolites in the leaves of Cyclocarya paliurus (Batal.) Iljinskaja (C. paliurus). The sample pretreatment method was optimized to have higher detection sensitivity in DESI. The changes of metabolites in C. paliurus were analyzed in depth with the integration of the spatial distribution information of metabolites. The main pathways for biosynthesis of flavonoid precursor and the effect of changes in compound structure on the spatial distribution were found. Spatial metabolomics can provide more metabolite information and a platform for the in-depth understanding of the biosynthesis and metabolism in plants.

Anthocyanins-natural pigment of colored rice bran: Composition and biological activities.

Rice by-products are a potential source of various bioactive substances with great processing potential, which are receiving increasing attention. Among them, rice bran is a by-product of rice milling, with high nutritional value and health benefits. Colored rice bran contains a large amount of anthocyanins responsible for color and bioactivities. And anthocyanins are often added to foods as a natural pigment, serving to enhance both the visual appeal and nutritional value. Recent advances in the composition and bioactivities of four common colored rice bran anthocyanins (black, purple, red, and purple red rice) are reviewed in this paper. Rice bran anthocyanins have been confirmed to exhibit biological potential for human health, with their main biological activities being antioxidant, anti-atherosclerosis, anti-cancer, neuroprotective, retinoprotective, immunomodulatory, anti-aging and anti-obesity effects. The structure of anthocyanins determines their biological activities. The anthocyanins composition of rice bran with different colors varied greatly, while that of rice bran with the same color is also slightly different, which is attributed to the rice varieties, growing environment and cropping conditions. However, it remains necessary to conduct further clinical studies to support the health activities of anthocyanins. The present review provides information value for the further development and comprehensive utilization of rice bran anthocyanins.

Release characteristic of bound polyphenols from tea residues insoluble dietary fiber by mixed solid-state fermentation with cellulose degrading strains CZ-6 and CZ-7.

The purpose of this work was to investigate the release characteristic of bound polyphenols (BP) from tea residues insoluble dietary fiber (IDF) by mixed solid-state fermentation (SSF) with cellulose degrading strains CZ-6 and CZ-7. The results implied that cellulase, ß-glucosidase and filter paper lyase activities were strongly correlated with the BP content. The scanning electron microscop and fourier transform infrared spectroscopy manifested that the cellulose network of the IDF was decomposed and dissolve, forming more loose fibrous structure. Additionally, 28 polyphenols components were detected and their biotransformation pathways were preliminary speculated. Moreover, the BP obtained by mixed SSF produced prominent inhibitory activities against α-glucosidase and α-amylase, as well as exhibited significant scavenging effects on DPPH•, ABTS+• free radicals and ferric reducing antioxidant power. These findings could further promote the utilization of BP from agricultural by-products in a more natural and economical method, CZ-6 and CZ-7 strains provide a new approach to expound the release and conversion of BP.

Extraction optimization of tea saponins from Camellia oleifera seed meal with deep eutectic solvents: Composition identification and properties evaluation.

Traditional organic solvent extractions of tea saponins have many drawbacks. This study aimed to establish an environment-friendly and efficient technology based on deep eutectic solvents (DESs) to extract tea saponins from Camellia oleifera seed meal. The solvent consisting of choline chloride and methylurea was screened as optimal DES. Under the optimal extraction conditions obtained by response surface methodology, the extraction yield of tea saponins reached 94.36 mg/g, which increased by 27% compared with ethanol extraction, while the extraction time was reduced by 50%. Analysis of UV, FT-IR, and UPLC-Q/TOF-MS indicated tea saponins did not alter during DES extraction. Surface activity and emulsification evaluation showed that extracted tea saponins could reduce interfacial tension at the oil-water interface with excellent foamability and foam stability, and they could form nanoemulsions (d32 < 200 nm) with excellent stability. This study provides a suitable approach for the efficient extraction of tea saponins.

Rheology, Texture and Swallowing Characteristics of a Texture-Modified Dysphagia Food Prepared Using Common Supplementary Materials.

A dysphagia diet is a special eating plan. The development and design of dysphagia foods should consider both swallowing safety and food nutritional qualities. In this study, the effects of four food supplements, namely vitamins, minerals, salt and sugar, on swallowing characteristics, rheological and textural properties were investigated, and a sensory evaluation of dysphagia foods made with rice starch, perilla seed oil and whey isolate protein was carried out. The results showed that all the samples belonged to foods at level 4 (pureed) in The International Dysphagia Diet Standardization Initiative (IDDSI) framework, and exhibited shear thinning behavior, which is favorable for dysphagia patients. Rheological tests showed that the viscosity of a food bolus was increased with salt and sugar (SS), while it decreased with vitamins and minerals (VM) at shear rates of 50 s-1. Both SS and VM strengthened the elastic gel system, and SS enhanced the storage modulus and loss modulus. VM increased the hardness, gumminess, chewiness and color richness, but left small residues on the spoon. SS provided better water-holding, chewiness and resilience by influencing the way molecules were connected, promoting swallowing safety. SS brought a better taste to the food bolus. Dysphagia foods with both VM and 0.5% SS had the best sensory evaluation score. This study may provide a theoretical foundation for the creation and design of new dysphagia nutritional food products.

Development of two immunochromatographic test strips based on signal amplification and selenium nanoparticles for the rapid detection of T-2 mycotoxin.

Conventional immunochromatographic test strips (ICSs) based on gold nanoparticle (AuNP) probes offer limited sensitivity. Here, AuNPs were separately labeled with monoclonal or secondary antibodies (MAb or SAb). In addition, spherical, homogeneously dispersed, and stable selenium nanoparticles (SeNPs) were also synthesized. By optimizing the preparation parameters, two ICSs based on the dual AuNP signal amplification (Duo-ICS) or SeNPs (Se-ICS) were developed for the rapid detection of T-2 mycotoxin. The detection sensitivities of the Duo-ICS and Se-ICS assays for T-2 were 1 ng/mL and 0.25 ng/mL, respectively, which were 3-fold and 15-fold more sensitive, respectively, than a conventional ICS. Furthermore, the ICSs were applied in the detection of T-2 in cereals, which requires higher sensitivity. Our findings indicate that both ICS systems can be used for rapid, sensitive, and specific detection of T-2 toxin in cereals and potentially other sample types.

Rapid and Simultaneous Detection of Aflatoxin B1, Zearalenone, and T-2 Toxin in Medicinal and Edible Food Using Gold Immunochromatographic Test Strip.

(1) Background: Medicinal and edible food and traditional Chinese medicine have been used to treat various diseases. However, their safety has not been thoroughly assessed. (2) Methods: An immunochromatographic test strip (ICS) was used for the first time to screen some mycotoxins, including aflatoxin B1 (AFB1), zearalenone (ZEN), and T-2 toxin, in medicinal and edible food and traditional Chinese medicine. Antibody/nano-gold particle coupling was used with the prepared ICS, and the pH, monoclonal antibody concentration, and antigen amount were optimized. The extraction sample solution was diluted 10 times with phosphate-buffered saline containing 0.5% Tween-20 and 0.05% sodium dodecyl sulfate to remove the complex matrix in medicinal and edible food. (3) Results: Under optimal conditions, the sensitivities of the developed ICS for AFB1, ZEN, and T-2 were 0.5, 5.0, and 5.0 ng/mL, respectively. Among the 30 medicinal and edible food samples tested, two samples (both of sand jujube kernels) were positive, and the results were verified by high-performance liquid chromatography and enzyme-linked immunosorbent assay and were consistent with the ICS test results. (4) Conclusions: The ICS could be used for rapid screening and simultaneous detection of mycotoxins at medicinal and edible food storage facilities.

Purification, composition and activity of bound polyphenols from mung bean coat dietary fiber.

In this study, the static adsorption-desorption performance of seven macroporous resins for bound polyphenols from mung bean coat dietary fiber (MBDF-BP) was compared, and NKA-9 macroporous resin was preferably screened for subsequent separation and purification. The composition of the purified products was identified and quantified, 44 major compounds were detected, with the main phenolic acid being p-hydroxybenzoic acid, which contained up to 8881.90 µg/g DW. The purification enriched flavonoids, with high contents of catechin (1419.03 µg/g DW) and vitexin (615.88 µg/g DW). The MBDF-BP purified products (pMBDF-BP) produced significant reversible inhibitory activity against α-glucosidase in a mixed-type inhibition manner, which was superior to the reported crude extracts. The antioxidant activity assays showed that pMBDF-BP exhibited distinct scavenging effects on DPPH•, ABTS+•, •OH free radicals, as well as reactive oxygen species (ROS) in Caenorhabditis elegans (C. elegans). These results demonstrated that NKA-9 macroporous resin could effectively enrich MBDF-BP extracts and enhance its antioxidant activity, which was promising to explore new sights into the applications of bound polyphenols from mung bean coat dietary fiber in functional foods or dietary supplements, thus contributing to the scientific utilization of mung bean coat resources and increasing the added value of related products.

Exploration of the role of bound polyphenols on tea residues dietary fiber improving diabetic hepatorenal injury and metabolic disorders.

Consumption of tea residues dietary fiber (TRDF) contributed to the relief of hyperglycemia symptoms in type 2 diabetes (T2D). Given the properties of TRDF abundant in bound polyphenols, the research intended to evaluate the effect of the presence or absence of bound polyphenols in TRDF on the improvement of diabetic complications (liver and kidney injury, metabolic disorders) in T2D rats induced by high-fat diet and streptozocin injection. Our results revealed that the presence of bound polyphenols in TRDF was remarkably beneficial for the amelioration of liver and kidney damage caused by T2D, which was supported by significant differences in activities of serum glutamic oxaloacetic transaminase (AST) and glutamic-pyruvic transaminase (ALT), contents of inflammatory factors in liver and kidney, the levels of kidney oxidative stress, as well as histopathological status between TRDF and bound polyphenols removed-TRDF (TRDF-DF) groups. In addition, metabolomic analysis revealed that TRDF interventions could increase the levels of metabolites such as S-Adenosylmethionine, L-Homophenylalanine and Riboflavin, as well as differ in the regulation of the metabolic pathways including arachidonic acid metabolism and cysteine and methionine metabolism as compared to TRDF-DF without bound polyphenols. These results suggested that bound polyphenols ensured the health-promoting effects for T2D complications of TRDF.

Gallic acid and heat moisture treatment improve pasting, rheological, and microstructure properties of Chinese yam starch-chitosan gels: A comparative study.

Nowadays，It is difficult for the polysaccharide-starch system to meet demand of practical production owing to the poor gel properties. Therefore, aiming to further improve the practical application of polysaccharide-starch gel, the effects of gallic acid (GA) and heat moisture treatment (HMT) on the gel properties and microstructure of yam starch/chitosan (YS/CS) composite gels were investigated. Swell power (SP) results showed that GA and HMT treatment respectively reduced the SP of YS gel by 3.24 g/g and 6.03 g/g, given that GA and HMT decrease the rheology of the water phase inhibiting the entry of water into the swollen starch. In the pasting process, HMT reduced pasting viscosity of the HMT/YS system because only little amylose was leached in the medium for elevating its viscosity after HMT. The rheological properties suggested that high temperature treatment of HMT facilitated the disruption and disintegration of starch granules resulting dynamic modulus had a decline trend. The elastic properties of GA/YS gels were enhanced with the addition of GA, which could be supported by the thicken lamellar observed in its microstructure. In general, GA and HMT effectively alter the gel properties of YS/CS gel system, and facilitate its practical application in food industry.

Soluble dietary fiber from tea residues with inhibitory effects against acrylamide and 5-hydroxymethylfurfural formation in biscuits: The role of bound polyphenols.

This study investigated the impact of soluble dietary fiber (SDF) from untreated (U-SDF), fermented (F-SDF) and high temperature cooked (H-SDF) from tea residues on formation of acrylamide (AA) and 5-hydroxymethylfurfural (5-HMF) in biscuits. Both 3% F-SDF and 2% H-SDF can simultaneously inhibit AA and 5-HMF and SDFs increased the types of volatile compounds in biscuits. After the determination of the bound polyphenol compositions in SDFs by LC-QTOF-MS/MS, six polyphenols with different structural characteristics were selected to explore their contributions on the inhibitory effect of SDFs and structure-inhibitory capacity relationships in the "glucose-asparagine-linoleic acid" model system. It showed that the inhibitory activities of those polyphenols were greatly affected by the number of hydroxyl groups and methoxy groups on the benzene ring. Almost all polyphenols were also found to scavenge hydroxyl radicals generated in reactions. Thus, this study suggests that the bound polyphenols of SDFs play a key role in the inhibition of AA and 5-HMF.

Dihydromyricetin ameliorates osteogenic differentiation of human aortic valve interstitial cells by targeting c-KIT/interleukin-6 signaling pathway.

Aims: Calcific aortic valve disease (CAVD) is a chronic cardiovascular disease with high morbidity that lacks effective pharmacotherapeutics. As a natural flavonoid extracted from Ampelopsis grossedentata, dihydromyricetin (DHM) has been shown to be effective in protecting against atherosclerosis; yet, the therapeutic role of DHM in CAVD remains poorly understood. Herein, we aimed to clarify the therapeutic implications of DHM in CAVD and the underlying molecular mechanisms in human valvular interstitial cells (hVICs). Methods and Results: The protein levels of two known osteogenesis-specific genes (alkaline phosphatase, ALP; runt-related transcription factor 2, Runx2) and calcified nodule formation in hVICs were detected by Western blot and Alizarin Red staining, respectively. The results showed that DHM markedly ameliorated osteogenic induction medium (OM)-induced osteogenic differentiation of hVICs, as evidenced by downregulation of ALP and Runx2 expression and decreased calcium deposition. The SwissTargetPrediction database was used to identify the potential AVC-associated direct protein target of DHM. Protein-protein interaction (PPI) analysis revealed that c-KIT, a tyrosine-protein kinase, can act as a credible protein target of DHM, as evidenced by molecular docking. Mechanistically, DHM-mediated inhibition of c-KIT phosphorylation drove interleukin-6 (IL-6) downregulation in CAVD, thereby ameliorating OM-induced osteogenic differentiation of hVICs and aortic valve calcification progression. Conclusion: DHM ameliorates osteogenic differentiation of hVICs by blocking the phosphorylation of c-KIT, thus reducing IL-6 expression in CAVD. DHM could be a viable therapeutic supplement to impede CAVD.

Screen of high efficiency cellulose degrading strains and effects on tea residues dietary fiber modification: Structural properties and adsorption capacities.

In our study, two high efficiency cellulose degrading strains were screened, isolated and identified as Cochliobolus kusanoi and Aspergillus puulaauensis by 18S rDNA gene sequencing. In addition, the composite microbial system was constructed to develop the synergistic effect among different strains. Under the optimum conditions, the yield of soluble dietary fiber from tea residues by mixed fermentation method (MF-SDF) dramatically increased compared to single strain fermentation. The structural analysis demonstrated that all samples possessed the representative infrared absorption peaks of polysaccharides, whereas MF-SDF revealed more loose structure, lower crystallinity and smaller molecular size. For the adsorption capacities indexes, MF-SDF also owned the highest adsorbing capacity for the water molecule, oil molecule, cholesterol molecule and nitrite ion. Overall, our data showed that mixed fermentation method could be better choices to improve the functional properties of dietary fiber, and screening of cellulose degrading strains could provide new thinkings for the study of dietary fiber modification and realize high-quality utilization of crop residues.

Amelioration of TPA-induced skin inflammation by the leaf extract of Vernonia amygdalina involves ERK/STAT3 (Ser727) signaling inhibition.

BACKGROUND: Uncontrolled inflammation causes health problems. Extracellular signal-regulated kinase (ERK) phosphorylates signal transducer and activator of transcription 3 (STAT3) at Ser727, resulting in inflammation. The leaf of Vernonia amygdalina (VA) is a medicinal herb for managing inflammation-associated diseases. Oral administration or topical application of VA leaf extract exerts anti-inflammatory effects in rat models. However, the anti-inflammatory mechanisms of the herb are not fully understood. PURPOSE: In this study, we aimed to investigate the involvement of ERK/STAT3 (Ser727) signaling in the anti-inflammatory effects of an ethanolic extract of VA leaves. STUDY DESIGN AND METHODS: Extracts of VA leaves were prepared with different concentrations of ethanol. A LPS-stimulated RAW264.7 cell model was used for in vitro assays, and a TPA (12-O-tetradecanoylphorbol-13-acetate)-induced ear edema mouse model was employed for in vivo assays. The 95% ethanol extract of VA leaves (VAE) exerted the strongest inhibitory effect on nitric oxide (NO) production in LPS-stimulated macrophages; thus it was selected for use in this study. Hematoxylin and eosin (H&E) staining was used to examine pathological conditions of mouse ear tissues. Griess reagent was employed to examine NO generation in cell cultures. Immunoblotting and ELISA were used to examine protein levels, and RT-qPCR was employed to examine mRNA levels. RESULTS: Topical application of VAE ameliorated mouse ear edema induced by TPA. VAE suppressed the phosphorylation of ERK (Thr202/Tyr204) and STAT3 (Ser727); and decreased protein levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-6, IL-1ß and tumor necrosis factor-α (TNF-α) in the mouse ear tissues and in LPS-stimulated RAW 264.7 cells. VAE also inhibited NO production, and lowered mRNA levels of IL-6, IL-1ß and TNF-α in the macrophages. CONCLUSIONS: VAE ameliorates TPA-induced mouse ear edema. Suppression of ERK/STAT3 (Ser727) signaling is involved in VAE's anti-inflammatory effects. These novel data provide further pharmacological justifications for the medicinal use of VA in treating inflammation-associated diseases, and lay the groundwork for developing VAE into a new anti-inflammatory agent.

Phytochemical composition, antioxidant activities and immunomodulatory effects of pigment extracts from Wugong Mountain purple red rice bran.

The study was to investigate the phytochemical composition, antioxidant activities and the immunomodulatory effects on cyclophosphamide-induced (cy-induced) immunosuppressed mice of purple red rice bran pigment extracts (PRBP). The phytochemical composition of total anthocyanins, total phenolic and total flavonoid contents were evaluated. Moreover, UV-Vis, FT-IR and UPLC-ESI-QTOF-MS spectra analysis identified for the first time the presence of seventeen anthocyanins in PRBP, including five anthocyanin aglycones and twelve acetylated anthocyanins, suggesting that PRBP were a highly acylated anthocyanin profile. The DPPH, ABTS+, hydroxyl radical scavenging activity and FRAP assays showed that PRBP had excellent antioxidant activities. Further, the results of animal experiments showed that PRBP alleviated immune organ damage and recovered damaged immune function, such as preventing the reduction of body weight, spleen and thymus organ indexes, and significantly increasing the levels of TNF-α, IL-6 and IL-1ß in spleen which indicated that PRBP alleviated immunosuppression in Cy-induced mice. The immunomodulatory activity of PRBP was reflected by the upregulation of MAPK signaling pathways after gavage. Taken together, these results suggest that PRBP possessed a certain antioxidant and immunomodulatory abilities. These findings will lead to a better understanding of the biological properties of PRBP and broaden its utilization in food processing.

Metabonomics combined with 16S rRNA sequencing to elucidate the hypoglycemic effect of dietary fiber from tea residues.

Tea residues are rich in dietary fiber, which possesses excellent physicochemical and functional properties in vitro. However, the hypoglycemic effect and mechanism of dietary fiber from tea residues are not clear. The study aimed to investigate the potential hypoglycemic effect of dietary fiber obtained from tea residues fermentation (TRDF) and reveal its related mechanisms of action in terms of both intestinal flora and metabolomics. The type 2 diabetes (T2D) rat model induced by high-fat diet and streptozotocin injection was applied in this study. Four weeks of TRDF intervention could remarkably ameliorate hyperglycemia, severe oxidative stress and insulin resistance of diabetic rats. Additionally, there was a significant increase of short chain fatty acids (SCFAs) concentrations in feces of diabetic rats after TRDF intervention. Furthermore, TRDF played a positive role in relieving intestinal microbiota dysbiosis by enriching beneficial bacteria (S24-7 and Prevotellaceae) and inhibiting harmful bacteria (Desulfovibrionaceae and Clostridiaceae). Metabolomic analysis showed that TRDF improved the amino acid metabolism and citrate cycle. The study elaborated on the hypoglycemic effect and potential mechanisms of TRDF through multiple pathways of gut microbiota and metabolites, which could provide theoretical basis for TRDF as a dietary supplement to manage T2D.

Elucidation of the interaction effect between dietary fiber and bound polyphenol components on the anti-hyperglycemic activity of tea residue dietary fiber.

Dietary fiber intake is beneficial for the prevention of some chronic metabolic diseases. Considering the characteristic that dietary fiber from tea residues (TRDF) is rich in bound polyphenols, the study aimed to elucidate the interaction effect between dietary fiber components (TRDF-DF) and bound polyphenol components (TRDF-BP) on the anti-hyperglycemic activity of TRDF. A type 2 diabetes (T2D) rat model induced by high-fat diet and streptozotocin injection was applied in this study. The results showed that bound polyphenol components rather than dietary fiber components were essential for the anti-hyperglycemic activity of TRDF, as evidenced by remarkable differences in fasting blood glucose (FBG), the insulin resistance index (HOMA-IR) and the levels of serum oxidative stress between the TRDF and TRDF-DF groups, as well as the up-regulation of the expression of insulin signaling pathway-related proteins in the liver after TRDF and TRDF-BP administration. In addition, the synergistic effect between TRDF-BP and TRDF-DF components modulated gut microbiota dysbiosis and increased the content of short chain fatty acids (SCFAs) via enriching beneficial bacteria and inhibiting harmful bacteria. The role of TRDF-BP and TRDF-DF as well as their interaction effect on the anti-hyperglycemic activity of TRDF are elucidated, which can provide theoretical basis for TRDF as a dietary supplement to manage T2D.

Investigation of thermal contaminants in coffee beans induced by roasting: A kinetic modeling approach.

The roasting-induced formation of thermal contaminants in coffee beans, including 5-hydroxymethylfurfural (5-HMF), acrylamide (AA), furan (F), 2-methyl furan (2-MF), and 3-methyl furan (3-MF), was investigated using a kinetic modeling approach. Results showed that AA and 5-HMF formation and elimination occur simultaneously in coffee beans during roasting and that the related reactions follow first-order reaction kinetics. The concentrations of F, 2-MF, and 3-MF increased throughout the roasting experiment, and variations in the concentrations of these compounds during roasting could be best described by empirical, logistic model. The increase in weight loss and decrease in moisture content of the beans during roasting also displayed first-order reaction kinetics. High coefficients of determination (R2 > 0.981) were observed for all fitted models, and the reaction rate constants of all models followed the Arrhenius law.

Sulfated Chinese yam polysaccharide enhances the immunomodulatory activity of RAW 264.7 cells via the TLR4-MAPK/NF-κB signaling pathway.

In this study, Chinese yam polysaccharide (CYP) was isolated from yam by hydroextraction and alcoholic precipitation. Subsequently, the chlorosulfate-pyridine (CSA-Pyr) method was used to obtain the sulfated Chinese yam polysaccharide derivative (S-CYP) to evaluate its immunomodulatory activity in RAW 264.7 cells and to investigate its mechanism of action. The results revealed that the sulfated modification altered the physicochemical properties of CYP but had no impact on the main chain structure. S-CYP demonstrated excellent immunomodulatory activity by increasing the viability of RAW 264.7 macrophage cells and stimulating the production of reactive oxygen species (ROS), nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin (IL)-6. Moreover, signal transduction experiments showed that S-CYP induced the activation of mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways through toll-like receptor 4 (TLR4), dramatically increasing p-ERK, p-JNK and p-p38 proteins. Meanwhile, immunofluorescence results showed that S-CYP could significantly promote the entry of NF-κB p65 into the nucleus, which is essential for triggering the NF-κB pathway. Furthermore, blocking antibody experiments revealed that specific inhibitors of TLR4, MAPKs, and NF-κB suppressed the generation of TNF-α and IL-6 in RAW 264.7 cells. These findings suggested that both CYP and S-CYP could be used as immunomodulatory agents and may have potential application prospects in the food and pharmaceutical industries.

Evaluation of trans fatty acids, carbonyl compounds and bioactive minor components in commercial linseed oils.

Trans fatty acids (TFAs), associated with the risks of coronary heart disease and diabetes, are formed by isomerization of unsaturated fatty acids during refining of linseed oils. In this study, TFAs and the chemical characteristics (acid value, peroxide value, carbonyl compounds, bioactive minor components and fatty acids) in 32 commercial linseed oils were investigated, and the correlation among them were further analyzed. Results showed that C18:3 TFAs were predominant TFAs in linseed oils and about 9% of the samples had TFA contents above 2 g/100 g fat, as well as the average level of TFA in the refined samples was higher than that in the unrefined oils. The correlation analyses suggested C18:3 TFAs exhibited significant negative correlations with acid value, levels of acetone, trans-2-nonenal, campesterol and α-linolenic acid. These results provided a comprehensive insight of TFAs in linseed oil and had important implications for consumers and linseed oil industry.