Alkylresorcinols in cereals and cereal products

The dietary impact of the Norman Conquest: A multiproxy archaeological investigation of Oxford, UK

Archaeology has yet to capitalise on the opportunities offered by bioarchaeological approaches to examine the impact of the 11th-century AD Norman Conquest of England. This study utilises an integrated multiproxy analytical approach to identify and explain changes and continuities in diet and foodways between the 10th and 13th centuries in the city of Oxford, UK. The integration of organic residue analysis of ceramics, carbon (δ13C) and nitrogen (δ15N) isotope analysis of human and animal bones, incremental analysis of δ13C and δ15N from human tooth dentine and palaeopathological analysis of human skeletal remains has revealed a broad pattern of increasing intensification and marketisation across various areas of economic practice, with a much lesser and more short-term impact of the Conquest on everyday lifestyles than is suggested by documentary sources. Nonetheless, isotope data indicate short-term periods of instability, particularly food insecurity, did impact individuals. Evidence of preferences for certain foodstuffs and cooking techniques documented among the elite classes were also observed among lower-status townspeople, suggesting that Anglo-Norman fashions could be adopted across the social spectrum. This study demonstrates the potential for future archaeological research to generate more nuanced understanding of the cultural impact of the Norman Conquest of England, while showcasing a method which can be used to elucidate the undocumented, everyday implications of other large-scale political events on non-elites.

Characterization of an alkylresorcinol synthase that forms phenolics accumulating in the cuticular wax on various organs of rye (Secale cereale)

Alkylresorcinols are bioactive compounds produced in diverse plant species, with chemical structures combining an aliphatic hydrocarbon chain and an aromatic ring with characteristic hydroxyl substituents. Here, we aimed to isolate and characterize the enzyme that forms the alkylresorcinols accumulating in the cuticular wax on the surface of all above-ground organs of rye. Based on sequence homology with other type-III polyketide synthases, a candidate alkylresorcinol synthase was cloned. Yeast heterologous expression showed that the enzyme, ScARS, is highly specific for the formation of the aromatic resorcinol ring structure, through aldol condensation analogous to stilbene synthases. The enzyme accepts long-chain and very-long-chain acyl-CoA starter substrates, preferring saturated over unsaturated chains. It typically carries out three rounds of condensation with malonyl-CoA prior to cyclization, with only very minor activity for a fourth round of malonyl-CoA condensation and cyclization to 5-(2'-oxo)-alkylresorcinols or 5-(2'-hydroxy)-alkylresorcinols. Like other enzymes involved in cuticle formation, ScARS is localized to the endoplasmic reticulum. ScARS expression patterns were found correlated with alkylresorcinol accumulation during leaf development and across different rye organs. Overall, our results thus suggest that ScARS synthesizes the cuticular alkylresorcinols found on diverse rye organ surfaces.

5-Heptadecylresorcinol, a Biomarker for Whole Grain Rye Consumption, Ameliorates Cognitive Impairments and Neuroinflammation in APP/PS1 Transgenic Mice

SCOPE

5-heptadecylresorcinol (AR-C17) is a biomarker for whole grain rye consumption, which is also an important active component with potential health benefits. The aim of this study is to investigate the protective effect of AR-C17 on cognitive deficits in amyloid precursor protein (APP)/PS1 transgenic mice.

METHODS AND RESULTS

Cognitive function is evaluated using Morris water maze test. The result shows that oral administration of AR-C17 (150 mg kg^-1 day^-1 ) for 5 months can ameliorate APP/PS1 transgenic mice memory impairment and improve learning ability. Moreover, AR-C17 treatment can notably reduce β-amyloid plaques accumulation and tau hyperphosphorylation while enhancing a disintegrin and metalloprotease 10 (ADAM10), postsynaptic density protein-95 (PSD-95), and synaptophysin protein expression in APP/PS1 transgenic mice. Furthermore, AR-C17 treatment reduces neuroinflammation by inhibiting microglial activation and astrogliosis as well as decreasing NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome-mediated IL-1β production and activating the sirtuin 3 (SIRT3)/superoxide dismutase 2 (SOD2) signaling pathway. Additionally, AR-C17 consumption significantly modulated gut dysbiosis in APP/PS1 transgenic mice through improving the relative abundance of Akkermansia and Lactobacillus while reducing the abundance of Clostridium and Desulfovibr according to16S rRNA analysis.

CONCLUSION

AR-C17 can be applied as a potential functional food ingredient to ameliorate cognitive impairments and prevent Alzheimer's disease.

5-Heptadecylresorcinol attenuates oxidative damage and mitochondria-mediated apoptosis through activation of the SIRT3/FOXO3a signaling pathway in neurocytes

5-Heptadecylresorcinol (AR-C17) is a main component of the alkylresorcinols (ARs), and has been widely used as a biomarker for whole grain rye consumption. Our study suggested AR-C17 attenuated neurocytes oxidative damage and apoptosis through SIRT3/FOXO3a signaling pathway.

Stone Milling versus Roller Milling in Soft Wheat: Influence on Products Composition

Wholegrain wheat flours are in great demand from consumers worldwide because they are considered healthier then refined flours. They can be obtained by either stone milling, which is experiencing a revival in Europe, or roller milling. In order to study compositional differences due to the milling technology and to explore the possibility of a better qualification of wholegrain flours by means of nutritionally oriented quality parameters, eight mixes of soft wheat grains were stone milled and roller milled and the milling products were analyzed for their protein, ash, lipids, total dietary fibre, total polyphenols and alkylresorcinols content. A wholegrain flour milled with a laboratory disk mill was used as a comparison and a set of seven wholegrain flours purchased on themarket were also analyzed and compared. The particle size distribution of stone milled and recombined roller milled flour was also studied. Considering the above mentioned parameters, we found that there is no compositional difference between a stone milled or a roller milled flour if, in this latter one, the milling streams are all recombined, but the particle size distribution was different. This might have an impact on the technological quality of flours and on the bioavailability of components.

Biomarkers of Whole-Grain and Cereal-Fiber Intake in Human Studies: A Systematic Review of the Available Evidence and Perspectives

High whole-grain consumption is related to better health outcomes. The specific physiological effect of these compounds is still unrevealed, partly because the accurate estimation of the intake of whole grains from dietary assessments is difficult and prone to bias, due to the complexity of the estimation of the intake by the consumer. A biomarker of whole-grain intake and type of whole-grain intake would be useful for quantifying the exposure to whole-grain intake. In this review, we aim to review the evidence on the potential biomarkers for whole-grain intake in the literature. We conducted a systematic search in Medline, Embase, Web of Science, and the Cochrane database. In total, 39 papers met the inclusion criteria following the PRISMA guidelines and were included. The relative validity, responsiveness, and reproducibility of these markers were assessed for short-, medium-, and long-term exposure as important criteria for the potential use of these biomarkers from a clinical and research perspective. We found three major groups of biomarkers: (1) alkylresorcinol, as well as its homologs and metabolites, assessed in plasma, adipose tissue biopsies, erythrocyte membranes, and urine; (2) avenacosides, assessed in urine samples; and (3) benzoxazinoid-derived phenylacetamide sulfates, assessed in blood and urine samples. The reviewed biomarkers may be used for improved assessment of associations between whole-grain intake and health outcomes.

Resorcinosides A and B, Glycosylated Alkylresorcinols from a Marine-Derived Strain of the Fungus Penicillium janthinellum

Two new glycosylated alkylresorcinols, resorcinosides A (1) and B (2), were isolated from a strain of the fungus Penicillium janthinellum derived from a marine sediment sample collected from Cu Lao Cham Island, Vietnam. The structures of 1 and 2 were established by interpretation of 1D and 2D NMR and high-resolution ESIMS data, and their absolute configurations were confirmed by the coupling constant of the anomeric proton, acid hydrolysis, subsequent HPLC analysis, Mosher's method, and quantum-mechanics-based computational analysis of NMR chemical shifts. The structure elucidation indicated that 1 and 2 are new alkylresorcinols with d-glucose, and 2 has an α-pyrone moiety attached to the aromatic ring. Compound 1 exhibited cytotoxic activity against the NUGC-3 cancer cell line with a GI₅₀ value of 9.3 μM.

Wheat Bran for Colon Cancer Prevention: The Synergy between Phytochemical Alkylresorcinol C21 and Intestinal Microbial Metabolite Butyrate

There is convincing evidence that consuming whole grains (WGs) may decrease the risk of colorectal cancer (CRC). Wheat bran (WB) is a rich source of dietary fiber and phytochemicals with health-promoting properties. However, the active components especially the interaction between different components in WG wheat have not been fully explored. Here, we investigated whether one of the major WB phytochemicals, alkylresorcinol (AR) C21, and the major active intestinal microbial metabolite of fiber, butyrate, could synergistically suppress human colon cancer cells. Our results demonstrated for the first time that the combination of C21 and butyrate synergistically inhibited the growth of human colon cancer cells and induced apoptosis. Further mechanistic studies demonstrated that the cotreatment of C21 and butyrate induced significant up-regulations in cleaved Poly(ADP-ribose) polymerase (PARP), cleaved caspase 3, p53 upregulated modulator of apoptosis (PUMA), cytochrome C, lipid-conjugated membrane-bound form of microtubule-associated protein 1A/1B-light chain 3 (LC3-II), and C/EBP homologous protein (CHOP) expressions, indicating the synergistic anticancer effects of C21 and butyrate were associated with induction of apoptosis, autophagy, and ER stress pathways. Notably, the C21 concentrations in the large intestinal tract of mice treated with human relevant doses of C21, were from 0.86 to 1.78 μmol/g, suggesting the C21 doses used in vitro may be achievable after daily WG wheat intake. These results provide novel insights into the dietary prevention of CRC regarding the potential interaction of bioactive WG wheat phytochemicals and the microbial metabolites of fiber.

Quantitative assessment of betainized compounds and associations with dietary and metabolic biomarkers in the randomized study of the healthy Nordic diet (SYSDIET)

BACKGROUND

Recently, a group of betainized compounds have been suggested to play a role in health effects in relation to a whole-grain-rich diet.

OBJECTIVES

The aims of this study were to develop a quantitative mass spectrometric method for selected betainized compounds in human plasma, and to investigate their association with nutrient intake and measures of metabolic health in participants of the SYSDIET study.

METHODS

The SYSDIET study was a controlled randomized intervention including individuals with metabolic syndrome, where the healthy Nordic diet (HND) group increased intakes of whole grains, canola oil, berries, and fish, whereas the control diet (CD) group consumed low-fiber cereal products, milk fat, and restricted amounts of fish and berries. A quantitative LC combined with triple quadrupole MS method for betainized compounds was developed and applied to fasting plasma samples from baseline (week 0) and the end of the intervention (week 18 or 24). Concentrations of betainized compounds were correlated with intakes of selected nutrients and fiber and measures of metabolic health.

RESULTS

Pipecolic acid betaine (PAB) concentrations were significantly higher in the HND group than in the CD group (P = 0.00032) at the end of the intervention and correlated directly (P < 0.0001) with intakes of dietary fiber (r = 0.376) and a biomarker related to whole-grain rye intake, namely the ratio of alkylresorcinol C17:0 to C21:0 (r = 0.442). PAB was associated inversely with fasting plasma insulin consistently at the beginning and at the end of the intervention (P < 0.001, r = -0.300; P < 0.01, r = -0.250, respectively), as well as IL-1 receptor antagonist (P < 0.01, r = -0.232 at the beginning; P < 0.01, r = -0.236 at the end) and serum LDL/HDL cholesterol (P < 0.01, r = -0.239 at the beginning; P < 0.01, r = -0.241 at the end).

CONCLUSIONS

Among adults with the metabolic syndrome, PAB plasma concentrations were associated with fasting insulin, inflammation, and lipids and were significantly increased with adoption of the HND. Further studies are needed to clarify the biological functions of betainized compounds. This trial was registered at clinicaltrials.gov as NCT00992641.

Effect of Alkylresorcinols on Autophagy, Migration, and Invasion of HepG2 Cells

Alkylresorcinols are phenolic lipids that mainly exist in the cortex of grains, and they exhibit anticancer activity against various cancer cells in vitro. However, the underlying action mechanisms are still unclear. In our study, the influence of alkylresorcinols C_19:0 and C_21:0 (ARs) upon migration, invasion, and autophagy in human hepatoblastoma HepG2 cells was evaluated. Results showed that ARs at 80 and 160 µg/mL significantly suppressed cells proliferation, migration, and invasion, downregulated the expression of proteins RhoA and MMP-7 associated with migration and invasion. ARs at 160 µg/mL, the rate of LC3 puncta was appreciably increased. After autophagy was blocked by 3-MA or CQ, the expression of LC3II was significantly increased in 3-MA+ARs group and p62 was significantly decreased in CQ+ARs group. The results indicate that ARs may promote autophagic flow. ARs (80, 160 µg/mL) significantly inhibited the expression of proteins p-mTOR, p-PI3K, and p-Akt related to the PI3K/Akt pathway. The results of the present study suggest that ARs can activate autophagy and suppresses the biological behaviors of HepG2 cells by inhibiting the activation of MMP-7, Rho/Rho-associated protein kinase, and activation of the phosphatidylinositol 3-kinase/Akt signaling pathway. PRACTICAL APPLICATION: The anticancer mechanism of ARs in wheat bran was studied, which provided a basis for the development of anticancer functional auxiliary food with wheat bran as raw material. It is of great practical significance to promote the effective utilization of grain processing by-products and improve the economic benefits of the grain industry.

Natural antioxidants of plant origin

Interest in the content of natural antioxidants in plant-based foods can be from the human health perspective, in terms of how these compounds might help promote one's health and wellness, or from the storage point-of-view, as the endogenous antioxidant constituents aid to extend a foodstuff's shelf-life. This chapter reports essential information about the mechanism of antioxidant action and methods employed for determination of their activity, classes of phenolic compounds (phenolic acids, flavonoids, lignans, stilbenes, tannins), sources of plant antioxidants (oil seeds, cereals, legumes, plants of the Lamiaceae family, tea and coffee, tree nuts, fruits, and berries), extraction strategies of phenolic compounds from plant material, and the influence of processing and storage on the content of natural antioxidants in foods and their antioxidant activity. Thermal processing, if not releasing bound phenolics from the structural matrices of the food, tends to decrease the antioxidant potential or, in the best case scenario, has no significant negative impact. Gentler sterilization processes such as high-pressure processing tend to better retain the antioxidant potential of a foodstuff than thermal treatments such as steaming, boiling, or frying. The impact of processing can be assessed by determining the antioxidant potential of foodstuffs either at the point of formulation or after different periods of storage under specified conditions.

Non-Destructive Determination of Alkylresorcinol (ARs) Content on Wheat Seed Surfaces and Prediction of ARs Content in Whole-Grain Flour

Alkylresorcinols (ARs) are beneficial for human health and can be used as biomarkers for whole-grain cereal intake. In previous studies, ARs content in whole-grain flour was determined by milling the seeds into powder, thus destroying their structure. In this paper, we adopted a non-destructive extraction approach. Chloroform and ethyl acetate extraction methods were carried out to extract lipids from the seed surface and whole-grain flour of 36 wheat varieties in China, respectively. GC-MS analysis identified chemical compounds in which ARs were the major compounds for all the samples. The average total content of ARs (624.223 µg/g) in whole grains was much higher than that on seed surfaces (4.934 µg/g), with a positive correlation (r = 0.863, p < 0.001) between these two parameters. The results suggested that the total ARs content on the seed surface can be used to predict their content in whole-grain flour. Without affecting the seed germination rate and damaging seed structure, we demonstrate that a non-destructive extraction approach is an appropriate and useful method, facilitating the development of rapid screening methods suitable for use in wheat breeding.

Long-Term Whole Grain Wheat and Rye Intake Reflected by Adipose Tissue Alkylresorcinols and Breast Cancer: A Case-Cohort Study

Whole grain rye (WGR) and whole grain wheat (WGW) have been suggested to protect against the development of breast cancer. In this study, we estimated long-term intake of WGR and WGW, using both a food frequency questionnaire (FFQ) and alkylresorcinol concentrations in adipose tissue biopsies, in relation to the risk of developing invasive breast cancer in a case-cohort study (n = 414 in the case group, n = 933 in the subcohort group) on the Danish “Diet, Cancer and Health” cohort. The median follow-up time of the subcohort was 5.3 years. Total WGR and WGW intake estimated with FFQ or reflected by total alkylresorcinol concentration in adipose tissue was not significantly associated with risk of breast cancer. However, after adjustment for total WGR and WGW intake, women in the highest quartile of relative WGR intake, reflected by the alkylresorcinol C17:0/C21:0 ratio, had a higher risk of overall breast cancer and estrogen-receptor-positive (ER+) breast cancer than women in the lowest quartile of relative WGR intake, while the risk of estrogen-receptor-negative (ER-) breast cancer incidence was unaffected. Similar results were obtained with the FFQ data. Based on these data, further investigation of the role of specific grain types in reducing or increasing breast cancer risk, and their overall impact on health, is warranted.

Targeted Metabolite Profiling-Based Identification of Antifungal 5-n-Alkylresorcinols Occurring in Different Cereals against Fusarium oxysporum

A rapid and convenient biochemometrics-based analysis of several cereal-derived extracts was used to identify n-alkyl(enyl)resorcinols (AR) as antifungals against Fusarium oxysporum. Total AR content and liquid chromatography/mass spectrometry (LC-MS)-based profiles were recorded for each extract, in addition to their antifungal activity, to help integrate these chemical and biological datasets by orthogonal partial least squares regression. In this study, we developed and used a micro-scale amended medium (MSAM) assay to evaluate the in vitro mycelial growth inhibition at low amounts of extracts. Triticale husk-derived extracts had the highest AR content (662.1 µg olivetol equivalent/g dry extract), exhibiting >79% inhibition at the highest doses (10.0–1.0 µg/µL). Correlation of the chemical and antifungal datasets using supervised metabolite profiling revealed that 5-n-nonadecanylresorcinol, 5-n-heneicosylresorcinol, and 5-n-tricosyl-resorcinol were the most active ARs occurring in cereal products from Colombia. Hence, we propose the biochemometrics-based approach as a useful tool for identifying AR-like antifungals against F. oxysporum.

Plasma alkylresorcinol metabolite, a biomarker of whole-grain wheat and rye intake, and risk of ischemic stroke: a case-control study

Background

Epidemiologic studies on whole grains and risk of stroke have reported inconsistent results, with some suggesting a protective effect but others showing a null association.

Objectives

The aim of this study was to examine whether plasma 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), a biomarker of whole-grain wheat and rye intake, is associated with risk of ischemic stroke.

Methods

A hospital-based case-control study was conducted between March 2011 and May 2016. Cases (n = 990) with first ischemic stroke were matched to controls (n = 990) by sex and age. Concentrations of plasma DHPPA were determined by high-performance liquid chromatography-tandem mass spectrometry. We calculated ORs for the association of plasma DHPPA concentrations with ischemic stroke risk through the use of logistic regression.

Results

Plasma DHPPA was inversely associated with ischemic stroke risk. After adjustment for potential confounding factors, the ORs for ischemic stroke across increasing quartiles of plasma DHPPA concentrations were 1 (referent), 0.76 (95% CI: 0.58, 0.99), 0.71 (95% CI: 0.54, 0.92), and 0.59 (95% CI: 0.45, 0.77), respectively (P-trend = 0.001). The inverse association was also observed in all subgroups of participants according to sex, age, body mass index, smoking status, alcohol consumption, history of hypertension, and history of diabetes.

Conclusions

Our study showed that higher plasma DHPPA concentrations were associated with lower risk of ischemic stroke. This finding provides further evidence to support the health benefits of whole-grain consumption.

Identification and heterologous reconstitution of a 5-alk(en)ylresorcinol synthase from endophytic fungus Shiraia sp. Slf14

A new type III polyketide synthase gene (Ssars) was discovered from the genome of Shiraia sp. Slf14, an endophytic fungal strain from Huperzia serrata. The intron-free gene was cloned from the cDNA and ligated to two expression vectors pET28a and YEpADH2p-URA3 for expression in Escherichia coli BL21(DE3) and Saccharomyces cerevisiae BJ5464, respectively. SsARS was efficiently expressed in E. coli BL21(DE3), leading to the synthesis of a series of polyketide products. Six major products were isolated from the engineered E. coli and characterized as 1,3-dihydroxyphenyl-5-undecane, 1,3-dihydroxyphenyl-5-cis-6'-tridecene,1,3-dihydroxyphenyl-5-tridecane, 1,3-dihydroxyphenyl-5-cis-8'-pentadecene, 1,3-dihydroxyphenyl-5-pentadecane, and 1,3-dihydroxyphenyl-5-cis-10'-heptadecene, respectively, based on the spectral data and biosynthetic origin. Expression of SsARS in the yeast also led to the synthesis of the same polyketide products, indicating that this enzyme can be reconstituted in both heterologous hosts. Supplementation of soybean oil into the culture of E. coli BL21(DE3)/SsARS increased the production titers of 1-6 and led to the synthesis of an additional product, which was identified as 5-(8'Z,11'Z-heptadecadienyl) resorcinol. This work thus allowed the identification of SsARS as a 5-alk(en)ylresorcinol synthase with flexible substrate specificity toward endogenous and exogenous fatty acids. Desired resorcinol derivatives may be synthesized by supplying corresponding fatty acids into the culture medium.

Identification, Quantification, and Anti-inflammatory Activity of 5- n-Alkylresorcinols from 21 Different Wheat Varieties

The characteristic constituent and anti-inflammatory activity of 5- n-alkylresorcinols (ARs) from 21 wheat bran samples in China were investigated in this study. The amount of ARs ranged from 697 to 1732 μg/g in the tested samples, which were composed of five different homologues. Among these homologues, C19:0 and C21:0 were the most abundant, followed by C17:0, C23:0, and C25:0. Moreover, the mRNA expression of IL-1β, IL-6, and TNF-α in LPS-activated RAW264.7 macrophage cells were significantly inhibited by ARs supplementation. The molecular mechanisms behind its anti-inflammatory activity could result from the suppression of nuclear factor-κB (NF-κB) and JNK/MAPK activation. ARs treatment notably decreased NF-κB p65 nuclear translocation and inhibitor κB (IκBα) kinase and JNK phosphorylation. Additionally, ARs homologues C17:0 had been proven to be the main active constituent. The results from this study could be used to promote the comprehensive utilization of wheat and its byproducts in improving human health.

Plasma Alkylresorcinol Metabolite, a Biomarker of Whole-Grain Wheat and Rye Intake, and Risk of Type 2 Diabetes and Impaired Glucose Regulation in a Chinese Population

OBJECTIVE

To examine the association of plasma alkylresorcinol metabolite 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), a biomarker of whole-grain wheat and rye intake, with type 2 diabetes (T2D) and impaired glucose regulation (IGR) in a Chinese population.

RESEARCH DESIGN AND METHODS

A total of 1,060 newly diagnosed T2D patients, 736 newly diagnosed IGR patients, and 1,443 control subjects with normal glucose tolerance were recruited in the case-control study. Plasma DHPPA concentrations were determined by high-performance liquid chromatography-tandem mass spectroscopy. Multivariate logistic regression analysis was used to evaluate the independent association of plasma DHPPA concentrations with the likelihood of T2D and IGR.

RESULTS

After adjustment for age, sex, BMI, and family history of diabetes, the odds ratios (95% CI) of T2D and IGR were 0.57 (0.45, 0.73) and 0.66 (0.50, 0.85), respectively, comparing the lowest with the highest quartile of plasma DHPPA concentrations. Further adjustment for current smoking status, current alcohol consumption, physical activity, history of hypertension, and educational level did not change the observed association materially. Similar results were also obtained in T2D and IGR groups combined. The inverse association of plasma DHPPA with T2D persisted in stratified analyses according to age, sex, BMI, current smoking status, current alcohol consumption, physical activity, family history of diabetes, and history of hypertension.

CONCLUSIONS

These findings suggested that higher plasma DHPPA concentrations were associated with lower odds of T2D and IGR. Further studies are warranted to confirm these findings in prospective cohorts.

PpORS, an ancient type III polyketide synthase, is required for integrity of leaf cuticle and resistance to dehydration in the moss, Physcomitrella patens

PpORS knockout mutants produced abnormal leaves with increased dye permeability and were more susceptible to dehydration, consistent with PpORS products being constituents of a cuticular structure in the moss. Type III polyketide synthases (PKSs) have co-evolved with terrestrial plants such that each taxon can generate a characteristic collection of polyketides, fine-tuned to its needs. 2'-Oxoalkylresorcinol synthase from Physcomitrella patens (PpORS) is basal to all plant type III PKSs in phylogenetic trees and may closely resemble their most recent common ancestor. To gain insight into the roles that ancestral plant type III PKSs might have played during early land plant evolution, we constructed and phenotypically characterized targeted knockouts of PpORS. Ors gametophores, unless submerged in water while they were developing, displayed various leaf malformations that included grossly misshapen leaves, missing or abnormal midribs, multicellular protuberances and localized necrosis. Ors leaves, particularly abnormal ones, showed increased permeability to the hydrophilic dye, toluidine blue. Ors gametophores lost water faster and were more susceptible to dehydration than those of the control strain. Our findings are consistent with ors leaves possessing a partially defective cuticle and implicate PpORS in synthesis of the intact cuticle. PpORS orthologs are present in a few moss species but have not been found in other plants. However, conceivably an ancestral ORS in early land plants may have contributed to their protection from dehydration.

Hydrothermal grain pre-processing and ultra-fine milling for the production of durum wheat flour fractions with high nutritional value

This work describes a process for producing durum wheat flour fractions with high potential nutritional value using grain pre-milling hydrothermal treatment and ultra-fine grinding (micronization), coupled with air classification. The difference of bioactive value of the flour fractions in relation to dietary fibre and phenolic compounds was monitored on four durum wheat cultivars by analysing total arabinoxylans, water extractable arabinoxylans and 5- n-alkylresorcinols. The extractability of the analysed compounds was most significantly affected by hydrothermal treatment. On average, the hydrothermally treated kernels compared with the untreated ones presented a marked increase of water extractable arabinoxylans and alkylresorcinols (about 25 and 48%, respectively), whereas slightly lower total arabinoxylans content (about 9%) was detected. The air classification applied on micronized kernels produced two flour fractions, coarse and fine, with the last showing, irrespective of the hydrothermal treatment, an increment of alkylresorcinols (24 and 22% in untreated and treated samples) and of total arabinoxylans (13 and 20% in untreated and treated samples) in comparison with the coarse one. The fine fraction (particles ≤ 120 µm), resulting richer in bioactive compounds, provides an interesting raw material to enrich traditional semolina in which, due to the removal of the external layers, the losses of total arabinoxylans and of alkylresorcinols were more than 60 and 90% alkylresorcinols, respectively, if compared with whole wheat grain.

Biomarkers of food intake and nutrient status are associated with glucose tolerance status and development of type 2 diabetes in older Swedish women

Background: Diet is frequently associated with both the development and prevention of type 2 diabetes (T2D), but there is a lack of objective tools for assessing the relation between diet and T2D. Biomarkers of dietary intake are unconfounded by recall and reporting bias, and using multiple dietary biomarkers could help strengthen the link between a healthy diet and the prevention of T2D.Objective: The objective of this study was to explore how diet is related to glucose tolerance status (GTS) and to future development of T2D irrespective of common T2D and cardiovascular disease risk factors by using multiple dietary biomarkers.Design: Dietary biomarkers were measured in plasma from 64-y-old Swedish women with different GTS [normal glucose tolerance (NGT; n = 190), impaired glucose tolerance (IGT; n = 209), and diabetes (n = 230)]. The same subjects were followed up after 5 y to determine changes in glucose tolerance (n = 167 for NGT, n = 174 for IGT, and n = 159 for diabetes). ANCOVA and logistic regression were used to explore baseline data for associations between dietary biomarkers, GTS, and new T2D cases at follow-up (n = 69).Results: Of the 10 dietary biomarkers analyzed, β-alanine (beef) (P-raw < 0.001), alkylresorcinols C17 and C19 (whole-grain wheat and rye) (P-raw = 0.003 and 0.011), eicosapentaenoic acid (fish) (P-raw = 0.041), 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF) (fish) (P-raw = 0.002), linoleic acid (P-raw < 0.001), oleic acid (P-raw = 0.003), and α-tocopherol (margarine and vegetable oil) (P-raw < 0.001) were associated with GTS, and CMPF (fish) (OR: 0.72; 95% CI: 0.56, 0.93; P-raw = 0.013) and α-tocopherol (OR: 0.71; 95% CI: 0.51, 0.98; P-raw = 0.041) were inversely associated with future T2D development.Conclusions: Several circulating dietary biomarkers were strongly associated with GTS after correction for known T2D risk factors, underlining the role of diet in the development and prevention of T2D. To our knowledge, this study is the first to use multiple dietary biomarkers to investigate the link between diet and disease risk.

Novel urinary alkylresorcinol metabolites as biomarkers of whole grain intake in free-living Swedish adults

SCOPE

Most studies on the role of whole grain for health rely on self-reported intake data, which are prone to measurement errors. There is a need for dietary biomarkers that can provide an objective measure of intake. Alkylresorcinols (AR) and their main metabolites 3,5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-propanoic acid (DHPPA) have been proposed as biomarkers for whole grain (WG) wheat and rye intake.

METHODS AND RESULTS

The medium-term reproducibility and relative validity of four putative urinary AR metabolites (3,5-dihydroxycinnamic acid (DHCA), 5-(3,5-dihydroxyphenyl) pentanoic acid (DHPPTA), 2-(3,5-dihydroxybenzamido)acetic acid (DHBA-glycine) and 3,5-dihydroxycinnamic acid amide (DHCA-amide)) as biomarkers for WG intake were investigated. Three-day weighed food records and 24-h urine samples from two occasions 2-3 months apart were obtained from 69 Swedish adults. WG intake was calculated and urinary AR metabolites were analyzed. The medium-term reproducibility determined for DHCA, DHPPTA, and DHBA-glycine varied from moderate-to-excellent (intra-class correlation coefficient = 0.63-0.85). Moreover, DHCA and DHPPTA excretion correlated well with self-reported total WG intake (r = 0.55, p < 0.001 and r = 0.42, p < 0.001, respectively).

CONCLUSION

DHCA or DHPPTA excretion in 24-h urine might be a suitable medium- to long-term biomarker of WG wheat and rye intake. These findings need to be confirmed in populations with low and infrequent WG intake.

Phytochemicals in whole grain wheat and their health-promoting effects

Accumulated evidence in epidemiological studies has consistently shown that consumption of whole grains (WGs) is inversely associated with risk of major chronic diseases such as certain types of cancer, type 2 diabetes, and cardiovascular diseases. Dietary fiber (DF) has been reported to be responsible for the health effects of WG consumption. Evidence from in vitro and in vivo studies is emerging that, in addition to DF and minerals, the unique phytochemicals in WGs may in part contribute to these health-promoting effects. WGs are rich sources of various phytochemicals. However, phytochemical contents and profiles in WG wheat are not systematically summarized yet, and the rapid rate of discovery of wheat phytochemicals necessitates an update on the current state of this field. Furthermore, the biological roles of phytochemicals in protective effects of WGs are also relatively underestimated compared to DFs. This manuscript summarized current research literature regarding phytochemicals that have been identified and characterized from wheat grains and wheat bran, and their corresponding contributions to the major health benefits of WG wheat consumption.

Substituting whole grains for refined grains in a 6-wk randomized trial has a modest effect on gut microbiota and immune and inflammatory markers of healthy adults

Background: Observational studies suggest an inverse association between whole-grain (WG) consumption and inflammation. However, evidence from interventional studies is limited, and few studies have included measurements of cell-mediated immunity.Objective: We assessed the effects of diets rich in WGs compared with refined grains (RGs) on immune and inflammatory responses, gut microbiota, and microbial products in healthy adults while maintaining subject body weights.Design: After a 2-wk provided-food run-in period of consuming a Western-style diet, 49 men and 32 postmenopausal women [age range: 40-65 y, body mass index (in kg/m2) <35] were assigned to consume 1 of 2 provided-food weight-maintenance diets for 6 wk.Results: Compared with the RG group, the WG group had increased plasma total alkyresorcinols (a measure of WG intake) (P < 0.0001), stool weight (P < 0.0001), stool frequency (P = 0.02), and short-chain fatty acid (SCFA) producer Lachnospira [false-discovery rate (FDR)-corrected P = 0.25] but decreased pro-inflammatory Enterobacteriaceae (FDR-corrected P = 0.25). Changes in stool acetate (P = 0.02) and total SCFAs (P = 0.05) were higher in the WG group than in the RG group. A positive association was shown between Lachnospira and acetate (FDR-corrected P = 0.002) or butyrate (FDR-corrected P = 0.005). We also showed that there was a higher percentage of terminal effector memory T cells (P = 0.03) and LPS-stimulated ex vivo production of tumor necrosis factor-α (P = 0.04) in the WG group than in the RG group, which were positively associated with plasma alkylresorcinol concentrations.Conclusion: The short-term consumption of WGs in a weight-maintenance diet increases stool weight and frequency and has modest positive effects on gut microbiota, SCFAs, effector memory T cells, and the acute innate immune response and no effect on other markers of cell-mediated immunity or systemic and gut inflammation. This trial was registered at clinicaltrials.gov as NCT01902394.

Amino acid digestibility of different rye genotypes in caecectomised laying hens

This study investigated the variability of amino acid (AA) digestibility of rye grains in laying hens. Relationships between AA digestibility and physical properties (thousand seed weight, test weight, falling number, and extract viscoelasticity), chemical composition (proximate nutrients, non-starch polysaccharides, AA, minerals, and inositol phosphates), gross energy concentration, and in vitro solubility of nitrogen (N) of the grains were also examined. Twenty rye genotypes were grown under standardised agronomic and environmental conditions as part of a collaborative research project known as "GrainUp". Each genotype was added to a basal diet at 500 g/kg at the expense of maize starch to produce 20 rye diets. The experimental design comprised four Latin Squares (6 × 6) distributed over two runs, resulting in 12 experimental periods. Caecectomised laying hens (LSL-Classic) were individually kept in metabolism cages. Excreta were collected quantitatively for 4 d, and AA digestibility of the rye genotypes was determined using a regression approach. The digestibility of AA was generally low but varied significantly among the 20 rye genotypes, especially for Lys (digestibility range 35-59%), Met (57-75%), Thr (34-54%), and Trp (36-71%). Nevertheless, physical and chemical characteristics as well as the in vitro solubility of N correlated in only a few cases with AA digestibility. Multiple linear regression was used to calculate equations to predict AA digestibility based on the analysed characteristics. However, their explanatory power, as judged by the adjusted R(2), was not sufficiently precise for practical application (below 0.6 for most AA). In conclusion, the AA digestibility of rye grain is generally low and varies significantly between crop genotypes. Equations based on its physical and chemical characteristics are not sufficiently precise to be useful for feed formulation.

Phenolic Compounds of Cereals and Their Antioxidant Capacity

Phenolic compounds play an important role in health benefits because of their highly antioxidant capacity. In this review, total phenolic contents (TPCs), phenolic acid profile and antioxidant capacity of the extracted from wheat, corn, rice, barley, sorghum, rye, oat, and millet, which have been recently reported, are summarized. The review shows clearly that cereals contain a number of phytochemicals including phenolics, flavonoids, anthocyanins, etc. The phytochemicals of cereals significantly exhibit antioxidant activity as measured by trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl radical scavenging, reducing power, oxygen radical absorbance capacity (ORAC), inhibition of oxidation of human low-density lipoprotein (LDL) cholesterol and DNA, Rancimat, inhibition of photochemilumenescence (PCL), and iron(II) chelation activity. Thus, the consumption of whole grains is considered to have significantly health benefits in prevention from chronic diseases such as cardiovascular disease, diabetes, and cancer because of the contribution of phenolic compounds existed. In addition, the extracts from cereal brans are considered to be used as a source of natural antioxidants.

Characterization and Discrimination of Ancient Grains: A Metabolomics Approach

Hulled, or ancient, wheats were the earliest domesticated wheats by mankind and the ancestors of current wheats. Their cultivation drastically decreased during the 1960s; however, the increasing demand for a healthy and equilibrated diet led to rediscovering these grains. Our aim was to use a non-targeted metabolomic approach to discriminate and characterize similarities and differences between ancient Triticum varieties. For this purpose, 77 hulled wheat samples from three different varieties were collected: Garfagnana T. turgidum var. dicoccum L. (emmer), ID331 T. monococcum L. (einkorn) and Rouquin T. spelta L. (spelt). The ultra high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-QTOF) metabolomics approach highlighted a pronounced sample clustering according to the wheat variety, with an excellent predictability (Q²), for all the models built. Fifteen metabolites were tentatively identified based on accurate masses, isotopic pattern, and product ion spectra. Among these, alkylresorcinols (ARs) were found to be significantly higher in spelt and emmer, showing different homologue composition. Furthermore, phosphatidylcholines (PC) and lysophosphatidylcholines (lysoPC) levels were higher in einkorn variety. The results obtained in this study confirmed the importance of ARs as markers to distinguish between Triticum species and revealed their values as cultivar markers, being not affected by the environmental influences.

Development of Lipophilic Antioxidants and Chloroplasts during the Sprouting of Diverse Triticum spp

The influence of sprouting times and illumination conditions on lipophilic antioxidants (carotenoids, tocochromanols, alkylresorcinols, and steryl ferulates), chlorophylls, and α-amylase activity was investigated using four varieties each of bread wheat (Triticum aestivum ssp. aestivum), spelt (T. aestivum ssp. spelta), durum (T. durum), emmer (T. dicoccum), and einkorn (T. monococcum). Carotenoid levels significantly increased during sprouting, particularly, under light exposure. In contrast, concentrations of other lipophilic antioxidants were affected to a lesser extent. Moreover, the quantitative development of lipophilic antioxidants was evidently determined by genotype. On the basis of the levels of carotenoids newly synthesized during sprouting, a chloroplast development index indicated that chloroplast ontogenesis during sprouting occurred at different species-dependent rates. Thermal degradation of carotenoids, tocochromanols, chlorophylls, and α-amylase activity was observed during the drying of sprouts at 40 and 90 °C, while alkylresorcinol and steryl ferulate levels remained unaffected. Wheat sprouts were shown to be potential functional ingredients to increase the nutritional value of cereal products.