Weight-conscious subjects and diabetics use the sulfonyl amide sweeteners saccharin acesulfame K to reduce their calorie sugar intake. However, intrinsic bitter aftertaste, which is caused by unknown mechanisms, limits of these sweeteners. Here, we show functional expression experiments in human embryonic kidney cells that activate two members TAS2R family (hTAS2R43 hTAS2R44) at concentrations known stimulate taste. These receptors are expressed tongue taste papillae. Moreover, sweet...

A fast and precise proton nuclear magnetic resonance (qHNMR) method for the quantitative determination of low molecular weight target molecules in reference materials natural isolates has been validated using ERETIC 2 (Electronic REference To access In vivo Concentrations) based on PULCON (PULse length CONcentration determination) methodology compared to gravimetric results. Using an Avance III NMR spectrometer (400 MHz) equipped with a broad band observe (BBO) probe, qHNMR was by...

Thermal treatment of aqueous solutions xylose and primary amino acids led to rapid development a bitter taste the reaction mixture. To characterize key compound causing this taste, novel bioassay, which is based on determination threshold products in serial dilutions HPLC fractions, was developed select most intense compounds complex mixture Maillard products. By application so-called dilution analysis (TDA) 21 fractions were obtained, among 1 fraction evaluated with by far highest impact....

The increasing incidence of invasive fungal infections (IFI) in immunocompromised patients emphasizes the need to improve diagnostic tools. We established a DNA microarray detect and identify from 14 pathogens (Aspergillus fumigatus, Aspergillus flavus, terreus, Candida albicans, dubliniensis, glabrata, lusitaniae, tropicalis, Fusarium oxysporum, solani, Mucor racemosus, Rhizopus microsporus, Scedosporium prolificans, Trichosporon asahii) blood, bronchoalveolar lavage, tissue samples...

Aimed at elucidating intense bitter-tasting molecules in coffee, various bean ingredients were thermally treated model experiments and evaluated for their potential to produce bitter compounds. As caffeic acid was found generate bitterness reminiscent of the taste a strongly roasted espresso-type reaction products formed screened compounds by means dilution analysis, most tastants isolated purified. LC-MS/MS as well 1-D/2-D NMR enabled identification 10 with rather low recognition threshold...

The aim of the present study was to apply an activity-guided screening procedure coffee brew identify a key chemopreventive compound by means in vitro antioxidant tests as well cell culture experiments and prove vivo activity that animal feeding experiment. Solvent fractionation, followed multiple-step ultrafiltration, revealed polar compounds with molecular weights below 1 kDa show major inhibitory effect on peroxidation linoleic acid predominant enzyme modulating NADPH−cytochrome c...

To investigate the influence of roasting time and temperature on degradation bitter precursors 3-O-caffeoyl quinic acid (1), 5-O-caffeoyl (2), 4-O-caffeoyl (3) as well formation tastants during coffee roasting, we prepared brews from beans roasted either at 260 degrees C for 60-600 s or 240 190-280 C. By means HPLC-UV/vis HPLC-MS/MS, bitter-tasting monocaffeoyl quinides (4-8), dicaffeoyl (9-11), 4-vinylcatechol oligomers (12-20) parent 1-3 were quantitatively analyzed in these brews....

Alphaproteobacteria of the metabolically versatile Roseobacter group (Rhodobacteraceae) are abundant in marine ecosystems and represent dominant primary colonizers submerged surfaces. Motility attachment prerequisite for characteristic 'swim-or-stick' lifestyle many representatives such as Phaeobacter inhibens DSM 17395. It has recently been shown that plasmid curing its 65-kb RepA-I-type replicon with >20 genes exopolysaccharide biosynthesis including a rhamnose operon results nearly...

Most 3D printing studies of foods deal with the feasibility and modulation textures independent flavor design aspects. As a cornerstone for combined control over texturing taste distribution, method starch-based food was developed in pioneering approach using dual extrusion coupled focused on-board near infrared (NIR) heating thermal stabilization. The facilitated hydrated starch-egg white powder-systems reproducible configurations. To systematically study influence inhomogeneous...

Diterpenoids form a diverse group of natural products, many which are or could become pharmaceuticals industrial chemicals. The modular character diterpene biosynthesis and the promiscuity enzymes involved make combinatorial promising approach to generate libraries diterpenoids. Here, we report on assembly in yeast ten synthases producing (+)-copalyl diphosphate-derived backbones four cytochrome P450 oxygenases (CYPs) combinations. This resulted production over 200 Based literature chemical...

Whereas freshly pressed linseed oil provides a delicate nutty flavor, lingering bitter off-taste is developing upon storage at room temperature. Using sensory guided fractionation approach, the key compound was identified in stored oil, and its structure determined as methionine sulfoxide-containing, cyclic octapeptide cyclo(PLFIM OLVF) by means of FTIR, LC-MS, NMR spectroscopy, amino acid analysis. Although this peptide known literature cyclolinopeptide E, taste activity has not previously...

Besides undesirable changes in the attractive aroma, a significant decrease intensity of bitterness as well change taste into lingering, harsh has long been known shelf-life limiting factor beer. Multiple studies have demonstrated that aging beer induces total amount cis- and trans-iso-alpha-acids, well-known bitter principles Although trans-iso-alpha-acids exclusively, not cis-iso-alpha-acids, were found to be degraded upon storage beer, key transformation products formed exclusively from...

To gain a more comprehensive knowledge on whether, besides the well-known piperine, other compounds are responsible for pungent and tingling oral impression imparted by black pepper, an ethanol extract prepared from pepper (Piper nigrum L.) was screened its key sensory-active nonvolatiles application of taste dilution analysis (TDA). Purification perceived with highest sensory impact, followed LC-MS 1D/2D NMR experiments as well synthesis, led to structure determination 25 phytochemicals,...

Dinoroseobacter shibae, a member of the Roseobacter clade abundant in marine environments, maintains morphological heterogeneity throughout growth, with small cells dividing by binary fission and large budding from one or both cell poles. This is lost if quorum sensing (QS) system silenced, concurrent decreased expression CtrA phosphorelay, regulatory conserved Alphaproteobacteria master regulator Caulobacter crescentus cycle. It consists sensor histidine kinase CckA, phosphotransferase ChpT...

Rapeseed products, such as protein concentrates, hold promise for addressing global demands, but their application in food products is limited by bitter and astringent taste. This study investigates the use of β-glucosidase (BG) laccase (LAC) enzymatic treatment, individually combined, to enhance flavor rapeseed concentrate (RPC). Untargeted metabolomics sensory analysis reveal that LAC reduces compound kaempferol 3-O-(2‴-O-sinapoyl-β-D-sophoroside) (K3OSS) well a general reduction other...

The teleost v1r-related ora genes are a small, highly conserved olfactory receptor gene family of only six genes, whose direct orthologues can be identified in lineages as far that cartilaginous fish. However, no ligands for fish class A related (ORA) had been uncovered so far. Here we have deorphanized the ORA1 using heterologous expression and calcium imaging. We report zebrafish recognizes with high specificity sensitivity 4-hydroxyphenylacetic acid. carboxyl group this compound is...

An aqueous ethanolic extract of the stem bark Garcinia buchananii showed strong antioxidative activity using H2O2 scavenging, oxygen radical absorbance capacity (ORAC), and Trolox equivalent antioxidant (TEAC) assays. Activity-guided fractionation afforded three new compounds, isomanniflavanone (1), an ent-eriodictyol-(3α→6)-dihydroquercetin-linked biflavanone, 1,5-dimethoxyajacareubin (2), depsidone garcinisidone-G (3), six known (2″R,3″R)-preussianon, euxanthone,...

To gain comprehensive insight into the interactions of key coffee odorants, like Strecker aldehydes, acetaldehyde, propanal, methylpropanal, 2- and 3-methylbutanal, methional, nonvolatile fraction coffee, an untargeted metabolomics approach was applied. Ultra performance liquid chromatography (UPLC)–time flight (TOF)-mass spectrometry (ESI–) profiling followed by statistical data analysis revealed a marker substance for beverage spiked with acetaldehyde accurate mass 217.0703 [M – H]−. This...

Linseed oil is rich in unsaturated fatty acids, and its increased consumption could aid health-promoting nutrition. However, rapid oxidation of linseed concomitant development bitterness impair consumers' acceptance. Previous research revealed that cyclolinopeptides, a group cyclic peptides inherent to oil, dominantly contribute the observed bitterness. In present study, fresh stored flaxseed were analyzed for presence cyclolinopeptides using preparative high-performance liquid...

In order to characterize red wine polymers with regard their binding properties aroma compounds (odorants), a qualitative and quantitative analysis of chemical degradation products after different treatments (thiolytic, acidic, alkaline depolymerization) high -molecular-weight (HMW) fractions was performed. Using 1H NMR, LC-ToF-MS, LC-MS/MS, HPIC revealed key structural features such as carbohydrates, organic acids, phenolic compounds, anthocyanins, anthocyanidins, amino flavan-3-ols...

Recent investigations on the bitterness of coffee as well 5-O-caffeoyl quinic acid roasting mixtures indicated existence another, yet unknown, bitter lactone besides previously identified compounds 5-O-caffeoyl-muco-γ-quinide, 3-O-caffeoyl-γ-quinide, 4-O-caffeoyl-muco-γ-quinide, 5-O-caffeoyl-epi-δ-quinide, and 4-O-caffeoyl-γ-quinide. In present study, this orphan was isolated from reaction products generated by dry heating 5-O-caffeoylquinic model, its structure determined unreported...