Metabolites of dietary atractyligenin glucoside in coffee drinkers' urine.

Arabica roast coffee contains a substantial amount of water soluble atractyligenin-2-O-ß-d-glucoside, which is ingested by consumption of coffee brew. Metabolomics data suggest this coffee compound is excreted as glucuronides, but the structures of conjugates have not been elucidated so far. We collected coffee drinkers' urine and isolated four metabolites by MS-guided liquid chromatographic fractionation. The structures were investigated by nuclear magnetic resonance (NMR) and time-of-flight mass spectrometry (ToF-MS) and identified as atractyligenin-19-O-ß-d-glucuronide (M1), 2ß-hydroxy-15-oxoatractylan-4α-carboxy-19-O-ß-d-glucuronide (M2), and 2ß-hydroxy-15-oxoatractylan-4α-carboxylic acid-2-O-ß-d-glucuronide (M3). An unconjugated metabolite (M4) was confirmed as atractyligenin. We analyzed spot urines from n = 6 coffee drinking individuals and detected the metabolites M1, M2 and M4 in every sample, and M3 in four out of six samples, suggesting interindividual differences in metabolism.

Metabolites of Key Flavor Compound 2,3,5-Trimethylpyrazine in Human Urine.

Pyrazines are among the most important compound class conveying the odor impressions "roasty", "nutty", and "earthy". They are formed by the Maillard reaction and occur ubiquitously in heated foods. The excretion of metabolites of the key flavor odorant 2,3,5-trimethylpyrazine, abundant in the volatile fraction of roasted coffee, was investigated. Based on literature suggestions, putative phase 1 and phase 2 metabolites were synthesized, characterized by nuclear magnetic resonance and mass spectroscopy data and used as standards for targeted, quantitative analysis of coffee drinkers' urine using stable-isotope-dilution-ultrahigh-performance liquid chromatography tandem mass spectroscopy (SIDA-UHPLC-MS/MS). The analysis of spot urine samples from a coffee intervention study revealed 3,6-dimethylpyrazine-2-carboxylic acid, 3,5-dimethylpyrazine-2-carboxylic acid, and 5,6-dimethylpyrazine-2-carboxylic acid were quantitatively dominating metabolites. Only negligible traces of pyrazinemethanols (3,6-dimethyl-2-pyrazinemethanol and 3,5,6-trimethylpyrazine-2-ol), glucuronides ((3,6-dimethylpyrazine-2-yl-)methyl-O-ß-D-glucuronide and (3,5-dimethylpyrazine-2-yl-)methyl-O-ß-D-glucuronide), and sulfates ((3,6-dimethylpyrazine-2-yl-)methyl-sulfate and (3,5-dimethylpyrazine-2-yl-)methyl-sulfate) were detected.

An aqueous extract of the brown alga Eisenia bicyclis extends lifespan in a sex-specific manner by interfering with the Tor-FoxO axis.

Food has a decisive influence on our health, to the extent where even lifespan can be directly affected by it. In the present work, we have examined the effects of an aqueous extract of the marine brown alga Eisenia bicyclis in terms of its potential to extend lifespan. For this purpose, we used the fruit fly Drosophila melanogaster as a model. The experiments showed that small amounts of Eisenia extract can extend lifespan by up to 40%. This effect is not only related to the median but also to the maximum lifespan. Interestingly, this life-extending effect is sex-specific, i.e. it occurs exclusively in females. Even under stressful nutritional conditions such as a high sugar diet, this effect is detectable. Mechanistic studies showed that this life-prolonging effect depends on a functional Tor and a functional FoxO signaling pathway. It can be concluded that components of the Eisenia extract prolong lifespan by interacting with the Tor-FoxO axis. This study may serve to stimulate further investigations, which on the one hand show such a life-prolonging effect also in other organisms and on the other hand identify the substances responsible for this effect. Finally, it may also encourage the increased use of arame as a health-promoting food supplement.

Offering Fiber-Enriched Foods Increases Fiber Intake in Adults With or Without Cardiometabolic Risk: A Randomized Controlled Trial.

INTRODUCTION: Previous efforts to increase fiber intake in the general population were disappointing despite growing awareness of the multiple benefits of a high fiber intake. Aim of the study was to investigate the acceptance and consumption of fiber-enriched foods. METHODS: One hundred and fifteen middle-aged healthy individuals with and without elevated waist circumference (> 102 cm in males and > 88 cm in females) were recruited and randomized to an intervention or an age- and sex-matched control group. Subjects assigned to the intervention group were invited to select fiber-enriched foods from a broad portfolio of products to increase fiber intake by 10 g/day. Control subjects could choose items from the same food basket without fiber enrichment. The primary outcome was the increase in dietary fiber intake, and secondary outcomes were changes in cardiometabolic risk factors, microbiota composition, food choices, and consumer acceptance of the fiber-enriched foods. RESULTS: Compared to baseline, daily fiber intake increased from 22.5 ± 8.0 to 34.0 ± 9.6 g/day after 4 weeks (p < 0.001) and to 36.0 ± 8.9 g/day after 12 weeks (p < 0.001) in the intervention group, whereas fiber intake remained unchanged in the control group. Participants rated the taste of the food products as pleasant without group differences. In both groups, the most liked foods included popular convenience foods such as pretzel breadstick, pizza salami, and pizza vegetarian. After 12 weeks of intervention, there were minor improvements in plasma lipids and parameters of glucose metabolism in both the intervention and control group compared to baseline, but no differences between the two groups. Increased fiber consumption resulted in an increased (p < 0.001) relative abundance of Tannerellaceae. CONCLUSIONS: Fiber-enrichment of popular foods increases fiber intake in a middle-aged population with and without cardiometabolic risk and may provide a simple, novel strategy to increase fiber intake in the population.

Identification and Quantitation of Taste-Active Compounds in Dried Scallops by Combined Application of the Sensomics and a Quantitative NMR Approach.

Application of the sensomics concept on dried scallops, a Japanese specialty produced from the adductor muscle of scallops, revealed after activity-guided fractionation with subsequent (comparative) taste dilution analyses besides nucleotides, amino acids, organic acids, and inorganic ions, the presence of taste-modulating quaternary ammonium compounds and opines in highly taste-active fractions. In order to recreate the taste of dried scallops, two independent quantitation approaches were applied and compared. The first approach used multiple targeted UHPLC-MS/MS and high-performance ion chromatography methods. Besides already established quantitation methods for basic taste compounds, a new HILIC-UHPLC-MS/MSMRM method for the quantitation of chromatographically challenging opines, using synthesized stable isotope-labeled standards, was developed. Furthermore, a qHNMR approach was applied, enabling a direct identification and quantitation of organic taste compounds in a food extract without prior fractionation using a reference 1H NMR database. Both methods yielded similar quantitative results of taste-active compounds in dried scallop extracts and subsequent taste recombination experiments based on these data were able to recreate the taste of dried scallops.

Dietary Piperine is Transferred into the Milk of Nursing Mothers.

INTRODUCTION: The diet of breastfeeding mothers could bring nurslings into contact with flavor compounds putatively contributing to early sensory programming of the infant. The study investigates whether tastants from a customary curry dish consumed by mothers are detectable in their milk afterwards and can be perceived by the infant. METHODS AND RESULTS: Sensory evaluation identifies pungency as the dominating taste impression of the curry dish. Its ingredients of chili, pepper, and ginger suggest the flavor compounds capsaicin, piperine, and 6-gingerol as analytical targets. Breastfeeding mothers are recruited for an intervention trial involving the consumption of the curry dish and subsequent collection of milk samples for flavor compound analysis. Targeted and untargeted mass spectrometric (MS)- investigations identify exclusively piperine as an intervention-derived compound in human milk. However, concentrations are below the human taste threshold. CONCLUSION: Piperine from pepper-containing foods transfers into the mother's milk within 1 h and is delivered to the nursling. Concentrations of 50 and 200 nM of piperine are 70-350 times below the human taste threshold, but TRPV1 (Transient Receptor Potential Vanilloid-1 ion channel) desensitization through frequent exposure to sub-taste-threshold concentrations could contribute to an increased tolerance at a later age.

Investigation of Kokumi Substances and Bacteria in Thai Fermented Freshwater Fish (Pla-ra).

A 16S rRNA next-generation sequencing technique was applied to investigate the microbial diversity and liquid chromatography-tandem mass spectrometry was used to identify glutamyl peptide profiles of 10 Thai fermented freshwater fish (Pla-ra) samples. A total of 12 genera of bacteria were able to be detected, with Tetragenococcus spp., Staphylococcus spp., and Lactobacillus spp. dominating. Of the 18 glutamyl peptides analyzed, 17 were found, even though the amounts detected were lower than the taste threshold. Despite this, an increase in mouthfulness sensation, reflecting kokumi activity, was clearly identified in most of the samples, which might be because of a synergistic effect of different sub-threshold compounds present in the samples. In principle component analysis, the relationship between microorganisms and glutamyl peptide generation was observed, especially between Tetragenococcus spp. and Lentibacillus spp. and the generation of γ-Glu-Val-Gly. Correlations between microbial diversity and the generation of taste enhancers were identified in this study.

Cloning and plant-based production of antibody MC10E7 for a lateral flow immunoassay to detect [4-arginine]microcystin in freshwater.

Antibody MC10E7 is one of a small number of monoclonal antibodies that bind specifically to [Arg4]-microcystins, and it can be used to survey natural water sources and food samples for algal toxin contamination. However, the development of sensitive immunoassays in different test formats, particularly user-friendly tests for on-site analysis, requires a sensitive but also cost-effective antibody. The original version of MC10E7 was derived from a murine hybridoma, but we determined the sequence of the variable regions using the peptide mass-assisted cloning strategy and expressed a scFv (single-chain variable fragment) format of this antibody in yeast and a chimeric full-size version in leaves of Nicotiana tabacum and Nicotiana benthamiana to facilitate inexpensive and scalable production. The specific antigen-binding activity of the purified antibody was verified by surface plasmon resonance spectroscopy and ELISA, confirming the same binding specificity as its hybridoma-derived counterpart. The plant-derived antibody was used to design a lateral flow immunoassay (dipstick) for the sensitive detection of [Arg4]-microcystins at concentrations of 100-300 ng/L in freshwater samples collected at different sites. Plant-based production will likely reduce the cost of the antibody, currently the most expensive component of the dipstick immunoassay, and will allow the development of further antibody-based analytical devices and water purification adsorbents for the efficient removal of toxic contaminants.