3D Porous Edible Scaffolds from Rye Secalin for Cell-Based Pork Fat Tissue Culturing.

Cellular agriculture holds hope for a sustainable alternative to conventional meat, yet multiple technical challenges remain. These include the large-scale production of edible scaffolds and culturing methods for fat tissues, which are key to meat texture, flavor, and nutritional values. Herein. we disclose our method in the facile fabrication of sponge-like plant protein scaffolds by applying commercial sugar cubes as highly permeable templates. The prepared secalin scaffolds feature a high porosity of 85-90%, fully interconnected pores, and high water stability. The mechanical properties of scaffolds could be tuned by varying sugar-to-protein weight ratio and post-water annealing treatment. Moreover, murine preadipocytes (3T3-L1) and porcine adipose-derived stem cells (ADSCs) readily infiltrate, adhere, proliferate, and differentiate on the secalin scaffolds to develop a fat tissue morphology. A cultured fat tissue was produced by culturing porcine ADSCs for 12 days, which remarkably resembles conventional porcine subcutaneous adipose tissue in appearance, texture, flavor, and fatty acid profiles. The research demonstrates the great potential of sponge-like secalin scaffolds for cultured fat tissue production.

All-in-one 2LabsToGo system for analysis of ergot alkaloids in whole rye.

Ergot alkaloids, naturally occurring mycotoxins of Claviceps fungi, pose health risks. This necessitates accurate analysis methods to ensure food safety. This study explored the open-source miniaturized all-in-one 2LabsToGo system to analyze ergot alkaloids in whole rye samples. It is suited for sustainable atline analysis as it combines all planar chromatography tasks, allowing low-cost quality control in milling plants. The LOD and LOQ of ergocristine were determined to be 0.4 and 1.2 ng/zone, respectively. Detectability of ergot alkaloids was proven to be below the current maximum limit of 500 µg/kg for rye milling products. The repeatability (%RSD) was 4.1 % and the coefficient of determination of the analytical response (R2) was 0.9918 for ergocristine. The mean recovery rate of ergot alkaloids in spiked whole rye grain was close to 100 %. Results of screening whole rye for ergot alkaloids were successfully verified by comparison with those obtained by conventional status quo HPTLC instrumentation.

Biogenic amines as an indicator of rye leaven quality during production and storage.

Rye leaven, the basic constituent of sour rye soup ('zurek' or white borsch), was obtained through three methods of initiating lacto-fermentation of rye flour. Optimal concentrations of NaCl (1.5%) and garlic (0.5%) were selected by utilizing the response surface methodology. During the production and storage of leaven at 10 °C and 20 °C, the secalin proteins of rye flour degraded significantly and the concentration of free amino acids increased, making the rye leaven an environment potentially conducive to the formation of biogenic amines. Putrescine (max. conc: 116.7 mg kg-1) and tyramine (max. conc: 63.4 mg kg-1) were the amines that occurred in the largest amounts in the leavens. The final concentration of histamine (after 150 days of storage) did not exceed 22 mg kg-1. Regardless of the method of initiation of fermentation, the products that contained fewer biogenic amines better retained their sensory characteristics (r ≤ -0.89, p < 0.05) and had a higher number of lactic acid bacteria (r ≤ -0.66, p < 0.05).

Inclusion of a Bacillus-based probiotic in non-starch polysaccharides-rich broiler diets.

This study examined the effects of a 3-strain Bacillus-based probiotic (BP; Bacillus amyloliquefaciens and two Bacillus subtilis) in broiler diets with different rye levels on performance, mucus, viscosity, and nutrient digestibility. We distributed 720 one-d-old female broilers into 72 pens and designed nine diets using a 3 × 3 factorial approach, varying BP levels (0, 1.2 × 106, and 1.2 × 107 CFU/g) and rye concentrations (0, 200, 400 g/kg). On d 35, diets with 200 or 400 g/kg rye reduced broiler weight gain (BWG). Diets with 400 g/kg rye had the highest FCR, while rye-free diets had the lowest (p ≤0.05). Adding BP increased feed intake and BWG in weeks two and three (p ≤0.05). It should be noted that the overall performance fell below the goals of the breed. Including rye in diets reduced the coefficient of apparent ileal digestibility (CAID) for protein, ether extract (EE), calcium, phosphorus, and all amino acids (p ≤0.05). Rye-free diets exhibited the highest CAID for all nutrients, except for methionine, EE, and calcium, while diets with 400 g/kg of rye demonstrated the lowest CAID (p ≤0.05). BP in diets decreased phosphorus CAID (p ≤0.05). Diets containing 1.2 × 107 CFU/g (10X) of BP exhibited higher CAID of methionine than the other two diets (p ≤0.05). Diets containing 10X of BP showed higher CAID of cysteine than diets with no BP (p ≤0.05). Ileal viscosity increased as the inclusion level of rye in the diets increased (p ≤0.05). The ileal concentration of glucosamine in chickens fed diets with 400 g/kg of rye was higher than in those fed diets with no rye (p ≤0.05). Furthermore, ileal galactosamine concentrations were elevated in diets with 200 and 400 g/kg of rye when compared to rye-free diets (p ≤0.05). However, BP in diets had no impact on ileal viscosity, galactosamine, or glucosamine (p > 0.05). In conclusion, the applied Bacillus strains appeared to have a limited capacity to produce arabinoxylan-degrading enzymes and were only partially effective in mitigating the negative impacts of rye arabinoxylans on broilers.

Tailor-made fermentation of sourdough reduces the acrylamide content in rye crispbread and improves its sensory and nutritional characteristics.

Thirty strains of lactic acid bacteria (LAB) and Saccharomyces cerevisiae E8.9 (wild type) were used to formulate fifteen combinations of starters by mixing two or three LAB with the yeast (ratio LAB: yeast, 10: 1). Such combinations were used to prepare rye sourdough and their performance in term of acidification and biochemical characteristics during fermentation at two temperatures (30 and 37 °C) and duration (4 and 8 h) were screened. The best thirteen sourdough formulations were selected and used for rye crispbread making. The analysis of acrylamide concentration demonstrated that 11 out 13 formulations resulted in significant decreases of concentration compared to the baker's yeast (control), with reductions up to 79.6 %. The rye sourdough crispbreads showed also higher amount of volatile organic compounds (VOCs) compared to the baker's yeast control. Two rye sourdough crispbreads, selected to represent the opposite extremes within the thirteen formulations in term of VOC profiles and fermentation performances, demonstrated better sensory and nutritional features, such as phytic acid reduction (up to 47.3 %), and enhanced total free amino acid compared to the control. These evidences suggest the potential of tailored sourdough fermentations as alternative and suitable biotechnological strategy for lowering acrylamide levels in rye crispbread.

Characteristic of the gene candidate SecARS encoding alkylresorcinol synthase in Secale.

BACKGROUND: Alkylresorcinols (ARs) are compounds belonging to the class of phenolic lipids. A rich source of ARs are cereal grains such as rye, wheat, triticale or barley. ARs found in plants are characterized by a variety of biological properties such as antimicrobial, antifungal and cytotoxic activity. Moreover, they are proven to have a positive influence on human health. Here, we aimed to find and characterize the gene with ARs synthase activity in the species Secale cereale. METHODS AND RESULTS: Using BAC library screening, two BAC clones containing the gene candidate were isolated and sequenced. Bioinformatic analyses of the resulting contigs were used to examine the structure and other features of the gene, including promoter, intron, 3'UTR and 5'UTR. Mapping using the FISH procedure located the gene on the 4R chromosome. Comparative analysis showed that the gene is highly similar to sequences coding for type III polyketide synthase. The level of gene expression in various parts of the plant was investigated, and the biochemical function of the gene was confirmed by heterologous expression in yeast. CONCLUSIONS: The conducted analyses contributed to a better understanding of the processes related to ARs synthesis. Although the research concerned the rye model, the knowledge gained may help in understanding the genetic basis of ARs biosynthesis in other species of the Poaceae family as well.

Daily assessment of malting-induced changes in the volatile composition of barley (Hordeum vulgare L.), rye (Secale cereale L.), and quinoa (Chenopodium quinoa Willd.).

Barley (Hordeum vulgare L.) is the traditional malting cereal and is primarily used for beverages, whereas rye (Secale cereale L.) is mainly used in baked goods. Conversely, quinoa (Chenopodium quinoa Willd.) is a gluten-free pseudocereal, rich in starch and high-quality proteins, and can be used in a similar manner to cereals. The sharp bitterness of unprocessed rye and the earthy aroma of native quinoa interfere with the acceptance and development of food products. Malting of barley is known to improve its processing properties and enhance its sensory quality. Therefore, the effect of germination and kilning on malt quality (e.g., viscosity) as well as the volatile composition of barley, rye, and quinoa were monitored. Moreover, temporal changes on the volatile patterns of rye and quinoa at the different stages of malting were compared to barley. In total, 34 volatile compounds were quantified in the three (pseudo)cereals; the alcohol group dominated in all unprocessed samples, in particular, compounds contributing grassy notes (e.g., hexan-1-ol). These grassy compounds remained abundant during germination, whereas kilning promoted the formation of Maillard reaction volatiles associated with malty and roasted notes. The volatile profiles of kilned barley and quinoa were characterized by high concentrations of the malty Strecker aldehyde, 3-methylbutanal. In contrast, green, floral notes imparted by phenylacetaldehyde remained dominant in rye malt. Hierarchical cluster analysis of the volatile data discriminated the samples into the different stages of malting, confirmed the similarities in the volatile patterns of barley and rye, and indicated clear differences to the quinoa samples. PRACTICAL APPLICATION: In this study, the effect of germination and kilning on the chemical and volatile composition of barley, rye, and quinoa was examined. Temporal changes on the volatile patterns of rye and quinoa at different stages of malting were compared to barley. Understanding the differences among the (pseudo)cereals as well as the influence of processing on malt quality and aroma development can help find new food applications.

Comparative study of the impact of malting on the aroma profiles of barley (Hordeum vulgare L.) and rye (Secale cereale L.).

Barley (Hordeum vulgare L.) remains the traditional malted cereal used for beverages, whereas rye (Secale cereale L.) is mainly used in baked goods. To evaluate the potential of rye malt for beverage production, malt quality indicators and the volatile composition of different rye malts were compared to barley malt. Sensory assessment revealed that pleasant malty and caramel aromas were formed by malting. Subsequently, three complementary isolation techniques and gas chromatography-olfactometry/mass spectrometry (GC-O/MS) were used for volatile analysis. Instrumental analysis detected 50 and 56 odor active volatiles in barley and rye, respectively. In part two, storage and the impact of three malting parameters on volatile formation were examined. Similarities in the malt volatile patterns were detected but the perceived intensity and composition varied. In barley, characteristic malty volatiles were lost during storage and staling compounds were formed. Conversely, nutty pyrazines and caramel furanones remained dominant in rye malts even after storage.

Metabolite Pattern Derived from Lactiplantibacillus plantarum-Fermented Rye Foods and In Vitro Gut Fermentation Synergistically Inhibits Bacterial Growth.

SCOPE: Fermentation improves many food characteristics using microbes, such as lactic acid bacteria (LAB). Recent studies suggest fermentation may also enhance the health properties, but mechanistic evidence is lacking. The study aims to identify a metabolite pattern reproducibly produced during sourdough and in vitro colonic fermentation of various whole-grain rye products and how it affects the growth of bacterial species of potential importance to health and disease. METHODS AND RESULTS: The study uses Lactiplantibacillus plantarum DSMZ 13890 strain, previously shown to favor rye as its substrate. Using LC-MS metabolomics, the study finds seven microbial metabolites commonly produced during the fermentations, including dihydroferulic acid, dihydrocaffeic acid, and five amino acid metabolites, and stronger inhibition is achieved when exposing the bacteria to a mixture of the metabolites in vitro compared to individual compound exposures. CONCLUSION: The study suggests that metabolites produced by LAB may synergistically modulate the local microbial ecology, such as in the gut. This could provide new hypotheses on how fermented foods influence human health via diet-microbiota interactions.

Analysis of the multi-physiological and functional mechanism of wheat alkylresorcinols based on reverse molecular docking and network pharmacology.

Alkylresorcinols (ARs) are phenolic lipids present in the bran part of whole grain wheat and rye, which possess antioxidant, anti-inflammatory, anti-cancer and anti-tumor properties. The physiological activities of ARs have been proven to be diverse; however, the specific molecular mechanisms are still unclear. In this study, reverse virtual screening and network pharmacology were used to explore the potential molecular mechanisms of the physiological function of ARs and their endogenous metabolites. The Metascape database was used for GO enrichment and KEGG pathway analysis. Furthermore, molecular docking was used to investigate the interactions between active compounds and potential targets. The results showed that the bioavailability of most ARs and their endogenous metabolites was 0.55 and 0.56, while the bioavailability of certain endogenous metabolites was only 0.11. Multiplex analysis was used to screen 73 important targets and 4 core targets (namely, HSP90AA1, EP300, HSP90AB1 and ERBB2) out of the 163 initial targets. The important targets involved in the key KEGG pathway were pathways in cancer (hsa05200), lipid and atherosclerosis (hsa05417), Th17 cell differentiation (hsa04659), chemical carcinogenesis-receptor activation (hsa05207), and prostate cancer (hsa05215). The compounds involved in the core targets were AR-C21, AR-C19, AR-C17, 3,5-DHPHTA-S, 3,5-DHPHTA-G, 3,5-DHPPTA, 3,5-DHPPTA-S, 3,5-DHPPTA-G, 3,5-DHPPTA-Gly and 3,5-DHPPA-G. The interaction force between them was mainly related to hydrogen bonds and van der Waals. Overall, the physiological activities of ARs are not only related to their multiple targets, but may also be related to the synergistic effect of their endogenous metabolites.

DHPPA, a major plasma alkylresorcinol metabolite reflecting whole-grain wheat and rye intake, and risk of metabolic syndrome: a case-control study.

PURPOSE: Whole-grain intake assessed through self-reported methods has been suggested to be inversely associated with the metabolic syndrome (MetS) risk in epidemiological studies. However, few studies have evaluated the association between whole-grain intake and MetS risk using objective biomarkers of whole-grain intake. The aim of this study was to examine the association between plasma 3-(3,5-Dihydroxyphenyl)-1-propanoic acid (DHPPA), a biomarker of whole-grain wheat and rye intake, and MetS risk in a Chinese population. METHODS: A case-control study of 667 MetS cases and 667 matched controls was conducted based on baseline data of the Tongji-Ezhou Cohort study. Plasma DHPPA concentrations were assessed by high-performance liquid chromatography-tandem mass spectrometry. The MetS was defined based on criteria set by the Joint Interim Statement. RESULTS: Plasma DHPPA was inversely associated with MetS risk. After adjustment for age, sex, body mass index, smoking status, alcohol drinking status, physical activity and education level, the odds ratios (ORs) for MetS across increasing quartiles of plasma DHPPA concentrations were 1 (referent), 0.86 (0.58-1.26), 0.77 (0.52-1.15), and 0.59 (0.39-0.89), respectively. In addition, the cubic spline analysis revealed a potential nonlinear association between plasma DHPPA and MetS, with a steep reduction in the risk at the lower range of plasma DHPPA concentration. CONCLUSION: Our study revealed that individuals with higher DHPPA concentrations in plasma had lower odds of MetS compared to those with lower DHPPA concentrations in plasma. Our findings provided further evidence to support health benefits of whole grain consumption.

Consumption of Yeast-Fermented Wheat and Rye Breads Increases Colitis and Mortality in a Mouse Model of Colitis.

BACKGROUND: Cereals are known to trigger for wheat allergy, celiac disease and non-celiac wheat sensitivity (NCWS). Inflammatory processes and intestinal barrier impairment are suspected to be involved in NCWS, although the molecular triggers are unclear. AIMS: We were interested if different bread types influence inflammatory processes and intestinal barrier function in a mouse model of inflammatory bowel disease. METHODS: Epithelial caspase-8 gene knockout (Casp8ΔIEC) and control (Casp8fl) mice were randomized to eight groups, respectively. The groups received different diets for 28 days (gluten-free diet, gluten-rich diet 5 g%, or different types of bread at 50 g%). Breads varied regarding grain, milling and fermentation. All diets were isocaloric. RESULTS: Regardless of the diet, Casp8ΔIEC mice showed pronounced inflammation in colon compared to ileum, whereas Casp8fl mice were hardly inflamed. Casp8fl mice could tolerate all bread types. Especially yeast fermented rye and wheat bread from superfine flour but not pure gluten challenge increased colitis and mortality in Casp8ΔIEC mice. Hepatic expression of lipopolysaccharide-binding protein and colonic expression of tumor necrosis factor-α genes were inversely related to survival. The bread diets, but not the gluten-rich diet, also decreased colonic tight junction expression to variable degrees, without clear association to survival and inflammation. CONCLUSIONS: Bread components, especially those from yeast-fermented breads from wheat and rye, increase colitis and mortality in Casp8ΔIEC mice highly susceptible to intestinal inflammation, whereas control mice can tolerate all types of bread without inflammation. Yet unidentified bread components other than gluten seem to play the major role.

Integrated LC-MS and GC-MS-Based Metabolomics Reveal the Effects of Plant Competition on the Rye Metabolome.

Plants compete with their neighbors about the limited resources available to them. Plants under induced stress resulting from competition may alter their metabolome to increase their resilience or enhance their defense mechanisms. In the present study, rye (Secale cereale) plants were cocultivated with different densities (3, 12, and 18 plants per pot) of Austrian pea (Pisum sativum subsp. arvense), hairy vetch (Vicia villosa), and Alexandrian clover (Trifolium alexandrinum L.) to elucidate the changes in the rye metabolome in response to the different levels of competition. Global metabolic profiling by liquid chromatography triple quadrupole tandem mass spectrometry (LC-QqQ-MS), liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS), and gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) was performed on rye plants, and the acquired data were analyzed using uni- and multivariate statistics. Targeted analysis showed that a high level of competition reduced the concentration of aglycone benzoxazinoids (BXs) and increased glycoside BXs in rye roots. Untargeted metabolomics analysis indicated an increase in the rye root content of the allelopathic compounds 4-hydroxybenzoic acid and uracil in response to competition. Untargeted analysis of rye shoots revealed that the plant competition increased the d-pyroglutamic acid, which is an elicitor of reactive oxygen species (ROS). Our results have enhanced the knowledge of the biochemical response of plant species to cocultivation.

Analysis of molecular weight and structural changes in water-extractable arabinoxylans during the breadmaking process.

Arabinoxylans are important for dough and breadmaking properties. It is not clear how arabinoxylans of different molecular weights behave during the breadmaking process as well as the changes in individual structures. We investigated changes in the molecular weight and structure of water-extractable arabinoxylans. It was revealed that molecules larger than high molecular weight arabinoxylans were formed during the mixing and 1st fermentation (105 min before 1st punch). High molecular weight arabinoxylan continued to be degraded from mixing to the proofing stage. The arabinose to xylose ratio increased at mixing and the 1st fermentation due to solubilization of highly substituted arabinoxylan. Low molecular weight arabinoxylan did not show degradation and structural changes during the fermentation process, whereas the weight average molecular weight of low molecular weight arabinoxylan significantly decreased (P < 0.05) at mixing. Water extractable arabinoxylan shows different behaviors for molecular weight and structural changes during the breadmaking process.

An efficient urine peptidomics workflow identifies chemically defined dietary gluten peptides from patients with celiac disease.

Celiac disease (CeD) is an autoimmune disorder induced by consuming gluten proteins from wheat, barley, and rye. Glutens resist gastrointestinal proteolysis, resulting in peptides that elicit inflammation in patients with CeD. Despite well-established connections between glutens and CeD, chemically defined, bioavailable peptides produced from dietary proteins have never been identified from humans in an unbiased manner. This is largely attributable to technical challenges, impeding our knowledge of potentially diverse peptide species that encounter the immune system. Here, we develop a liquid chromatographic-mass spectrometric workflow for untargeted sequence analysis of the urinary peptidome. We detect over 600 distinct dietary peptides, of which ~35% have a CeD-relevant T cell epitope and ~5% are known to stimulate innate immune responses. Remarkably, gluten peptides from patients with CeD qualitatively and quantitatively differ from controls. Our results provide a new foundation for understanding gluten immunogenicity, improving CeD management, and characterizing the dietary and urinary peptidomes.

Regulated and Non-Regulated Mycotoxin Detection in Cereal Matrices Using an Ultra-High-Performance Liquid Chromatography High-Resolution Mass Spectrometry (UHPLC-HRMS) Method.

Cereals represent a widely consumed food commodity that might be contaminated by mycotoxins, resulting not only in potential consumer health risks upon dietary exposure but also significant financial losses due to contaminated batch disposal. Thus, continuous improvement of the performance characteristics of methods to enable an effective monitoring of such contaminants in food supply is highly needed. In this study, an ultra-high-performance liquid chromatography coupled to a hybrid quadrupole orbitrap mass analyzer (UHPLC-q-Orbitrap MS) method was optimized and validated in wheat, maize and rye flour matrices. Nineteen analytes were monitored, including both regulated mycotoxins, e.g., ochratoxin A (OTA) or deoxynivalenol (DON), and non-regulated mycotoxins, such as ergot alkaloids (EAs), which are analytes that are expected to be regulated soon in the EU. Low limits of quantification (LOQ) at the part per trillion level were achieved as well as wide linear ranges (four orders of magnitude) and recovery rates within the 68-104% range. Overall, the developed method attained fit-for-purpose results and it highlights the applicability of high-resolution mass spectrometry (HRMS) detection in mycotoxin food analysis.

Correlation between leaf epicuticular wax composition and structure, physio-biochemical traits and drought resistance in glaucous and non-glaucous near-isogenic lines of rye.

The objective of this research was to investigate the differences between glaucous and non-glaucous near-isogenic lines (NILs) of winter rye (Secale cereale L.) in terms of epicuticular wax layer properties (weight, composition, and crystal morphology), selected physiological and biochemical responses, yield components, above-ground biomass, and plant height under soil drought stress. An important aspect of this analysis was to examine the correlation between the above characteristics. Two different NIL pairs were tested, each consisting of a typical glaucous line and a non-glaucous line with a recessive mutation. The drought experiment was conducted twice (2015-2016). Our study showed that wax accumulation during drought was not correlated with higher leaf hydration and glaucousness. Environmental factors had a large impact on the response of the lines to drought in individual years, both in terms of physiological and biochemical reactions, and the composition of epicuticular leaf wax. The analysed pairs displayed significantly different responses to drought. Demonstration of the correlation between the components of rye leaf wax and the physiological and biochemical parameters of rye NILs is a significant achievement of this work. Interestingly, the study showed a correlation between the wax components and the content of photosynthetic pigments and tocopherols, whose biosynthesis, similarly to the biosynthesis of wax precursors, is mainly located in chloroplasts. This suggests a relationship between wax biosynthesis and plant response to various environmental conditions and drought stress.

Comprehensive analysis of structural, functional, and evolutionary dynamics of Leucine Rich Repeats-RLKs in Thinopyrum elongatum.

Leucine Rich Repeats-receptor-like protein kinases (LRR-RLKs) regulate several critical biological processes ranging from growth and development to stress response. Thinopyrum elongatum harbours many desirable traits such as biotic and abiotic stress resistance and therefore commonly used by wheat breeders. In the present investigation, in-silico analysis of LRR-RLKs yielded 589 genes of which 431 were membrane surface RLKs and 158 were receptor like cytoplasmic kinases. An insight into the gene and protein structure revealed quite a conserved nature of these proteins within subgroups. A large expansion in LRR-RLKs was due to tandem and segmental duplication event. Maximum number of tandem and segmentally duplicated pairs was observed in LRR-VI and LRR-XII subfamily, respectively. Furthermore, syntenic analyses revealed that chromosome 6 harboured more (48) tandem duplicated genes while chromosome 7 possessed more (47) segmentally duplicated genes. A detailed analysis about the gene duplication events coupled with expression profiles during Fusarium graminearum infection and water deficiency unravelled the expansion of the gene family with sub functionalization and neofunctionalization. Interaction network analysis showed that LRR-RLKs can heterodimerize upon ligand binding to perform various plant functional attributes.

Impact of arabinoxylan on characteristics, stability and lipid oxidation of oil-in-water emulsions: Arabinoxylan from wheat bran, corn bran, rice bran, and rye bran.

To investigate the impact of arabinoxylan (AX) on the physical and oxidative stability of oil-in-water emulsions, AX from wheat bran, corn bran, rice bran, or rye bran was incorporated into the production of whey protein isolate-stabilised emulsions. Decreased interfacial charge and increased mean particle diameters were recorded in all fresh emulsions with 0.1%-0.5% AX, as recorded by the ζ-potential and particle size measurement, indicating the adsorption of AX onto the oil droplets. No phase separation was observed in all emulsions with ≤0.3% AX after 14-day storage in dark. Spectrophotometric analysis demonstrated that all AX lowered the peroxide value and thiobarbituric acid reactive substance concentration in emulsions, with AX from rice bran being slightly more effective. Consequently, AX has the potential to be used as a natural interfacial antioxidant in emulsions, and the antioxidant capacity of AX varies with its source.

Isolation of saturated alkylresorcinols from rye grains by countercurrent chromatography.

Alkylresorcinols (5-alkyl-1,3-dihydroxybenzenes) are amphiphilic phenolic lipid compounds that are abundant in cereals with highest contents in rye. Alkylresorcinols are suspected to show a wide range of favourable biological activities. For such and further testing, highly pure alkylresorcinol standards are required. Especially, purities >> 98% were partly difficult to obtain in the past. Here, we aimed to isolate the most abundant (saturated) alkylresorcinols from rye using countercurrent chromatography. To achieve very high purity, alkylresorcinol-containing extract (∼7.14 g) of rye grains (cold extracts with cyclohexane/ethyl acetate (46/54, w/w)) were preparatively transesterified followed by a preparative hydrogenation. Countercurrent chromatography separation of ∼1 g hydrogenated and transesterified rye grain extract using the solvent system n-hexane-ethyl acetate-methanol-water (9:1:9:1, v/v/v/v) yielded 51.8 mg AR17:0, 77.4 mg AR19:0, 57.2 mg AR21:0, 28.8 mg AR23:0 and 11.5 mg AR25:0 with purities >99% in either case. The isolated alkylresorcinol homologues can be used for subsequent bioassays.