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There is an urgent need to understand the behavior of novel coronavirus (SARS-COV-2), which is the causative agent of COVID-19, and to develop point-of-care diagnostics. Here, a glyconanoparticle platform is used to discover that N-acetyl neuraminic acid has high affinity towards the SARS-COV-2 spike glycoprotein, demonstrating its glycan-binding function. Optimization of the particle size and coating enabled detection of the spike glycoprotein in lateral flow and showed selectivity over the SARS-COV-1 spike protein. Using a viral particle mimic, paper-based lateral flow detection was demonstrated in under 30 minutes showing the potential of this system as a low-cost detection platform.

In this study, we explored possibilities to develop low glycaemic-index foods from barley (Hordeum vulgare – Hv). Barley has a potential to suppress postprandial blood glucose levels, possibly because of its high content of β-glucan (BG). BG content is particularly high in Hordeum vulgare Subsp. spontaneum (Hs), which is the wild ancestor of cultivated barley. Increasing amylose content in starch is another way to decrease the glycaemic index of a starch-rich-food. Therefore, a recently developed Amylose-only barley grain (AO) containing a 99% amylose starch was included. Two in vitro gastro-intestinal models were used to predict glycaemic indices (pGIs). Grains and bread from Hs and AO showed lower pGIs as compared to Hv. The low pGI value of AO was due to the resistant starch. The low pGI of Hs barley grains was caused by increased viscosity of the digesta. A simulated colon was used to predict potential effects on microbiota.

Highlights • We investigated the mechanisms of lipid bioaccessibility from almond muffins. • An in vitro dynamic gastric model was used to simulate human digestion. • A pilot ileostomy study was performed to define the rate of lipid release. • Microstructural analysis proved that some lipid remained encapsulated within matrix. • The cell-wall is the main factor regulating the lipid bioaccessibility., This study compares in vitro and in vivo models of lipid digestion from almond particles within a complex food matrix (muffins) investigating whether the cell-wall barrier regulates the bioaccessibility of nutrients within this matrix. Muffins containing small (AF) or large (AP) particles of almond were digested in triplicate using an in vitro dynamic gastric model (DGM, 1 h) followed by a static duodenal digestion (8 h). AF muffins had 97.1 ± 1.7% of their lipid digested, whereas AP muffins had 57.6 ± 1.1% digested. In vivo digestion of these muffins by an ileostomy volunteer (0–10 h) gave similar results with 96.5% and 56.5% lipid digested, respectively. The AF muffins produced a higher postprandial triacylglycerol iAUC response (by 61%) than the AP muffins. Microstructural analysis showed that some lipid remained encapsulated within the plant tissue throughout digestion. The cell-wall barrier mechanism is the main factor in regulating lipid bioaccessibility from almond particles.

The term bioaccessibility refers to the proportion of a nutrient released from a complex food matrix during digestion and, therefore, becoming potentially available for absorption in the gastrointestinal tract. In the present study, we assessed the starch and protein bioaccessibility from a range of wheat endosperm products differing in particle size. Five porridge meals (size A, flour, mean particle size 0.11 mm, size B, small, mean particle size 0.38 mm, size C, semolina, mean particle size 1.01 mm, size D, medium, mean particle size 1.44 mm, size E, large, mean particle size 1.95 mm) with theoretically different postprandial glycaemic responses were subjected to oral processing in vitro, followed by simulated gastric and duodenal digestion. A significant increase (P

The Dynamic Gastric Model (DGM) is an in-vitro system which aims to closely replicate the complex mixing, dynamic biochemical release and emptying patterns of the human stomach. In this study, the DGM was used to understand how the polymer content of hydrophilic matrices influences drug release in fasted and fed dissolution environments. Matrices containing a soluble model drug (caffeine) and between 10 and 30% HPMC 2208 (METHOCEL(®) K4M CR) were studied in the DGM under simulated fasted and fed conditions. The results were compared with compendial USP I and USP II dissolution tests. The USP I and II tests clearly discriminated between formulations containing different polymer levels, whereas the fasted DGM test bracketed drug release profiles into three groups and was not able to distinguish between some different formulations. DGM tests in the fed state showed that drug release was substantially influenced by the presence of a high fat meal. Under these conditions, there was a delay before initial drug release, and differences between matrices with different polymer contents were no longer clear. Matrices containing the typical amount of HPMC polymer (30% w/w) exhibited similar release rates under fed and fasted DGM conditions, but matrices with lower polymer contents exhibited more rapid drug release in the fasted state. In both the fasted and fed states erosion mechanisms appeared to dominate drug release in the DGM: most likely a consequence of the changing, cylindrical forces exerted during simulated antral cycling. This is in contrast to the USP tests in which diffusion played a significant role in the drug release process. This study is one of the first publications where a series of extended release (ER) formulations have been studied in the DGM. The technique appears to offer a useful tool to explore the potential sensitivity of ER formulations with respect to the gastric environment, especially the presence of food.

Objective: The bioaccessibility of bioactives from pistachios has not been previously evaluated. In the present study we quantified the release of polyphenols, xanthophylls (lutein), and tocopherols from pistachios (raw pistachios, roasted salted pistachios, and muffins made with raw pistachios) during simulated human digestion. Methods: A dynamic gastric model of digestion that provides a realistic and predictive simulation of the physical and chemical processing and accurately mimics the residence time and the luminal environment within the human stomach was used for the digestion studies. Results: More than 90% of the polyphenols were released in the gastric compartment, with virtually total release in the duodenal phase. No significant differences were observed between raw shelled and roasted salted pistachio. The presence of a food matrix (muffin) decreased the bioaccessibility of protocatechuic acid (78%) and luteolin (36%). Almost 100% bioaccessibility of lutein and tocopherols was found after duodenal digestion, with no difference among the three samples. Conclusion: The rapid release of the assayed bioactives in the stomach maximizes the potential for absorption in the duodenum and contributes to the beneficial relation between pistachio consumption and health-related outcomes.

Modulation of the human gut microbiota has proven to have beneficial effects on host health. The aim of this work was to evaluate the effect of sun-dried raisins (SR) on the composition of the human gut microbiota. A full model of the gastrointestinal tract, which includes simulated mastication, a dynamic gastric model, a duodenal model and a colonic model of the human large intestine, was used. An increase in the numbers of bifidobacteria and lactobacilli was observed by plate-counting in response to the addition of either SR or FOS after 8 and 24 h fermentation. A significant decrease in Firmicutes and Bacteroidetes was observed in SR samples after 8 and 24 h fermentation. FOS resulted in the greatest production of short chain fatty acids. Sun-dried raisins demonstrated considerable potential to promote the colonization and proliferation of beneficial bacteria in the human large intestine and to stimulate the production of organic acids.

New chiral C1-symmetric dipyridylmethane ligands have been prepared from naturally occurring monoterpenes according to a method based on two consecutive constructions of the pyridine rings. These ligands have been assessed in the enantioselective palladium catalyzed allylic alkylation of 1,3-diphenylprop-2-enyl acetate with dimethylmalonate. Enantioselectivity up to 68% ee has been obtained.

Characterisation of the effect of food on the bio-performance of modified and extended release dosage forms can be very challenging due to the need to replicate the dynamic biochemical conditions of the human gut as well as the complex physical processing modalities under fed state. Classical compendial methods are useful for testing the quality of pharmaceutical dosage forms but typically have limitations in the accurate prediction of food-effect in-vivo. Preliminary evaluation of the Dynamic Gastric Model (DGM) shows that it can provide substantially more detailed mechanistic information on dosage form properties compared to conventional compendial testing. The potential effect of food on the drug release and physical properties of a hydrophilic matrix formulation containing a model drug, hydrochlorothiazide, was studied using compendial methods, bio-relevant media and the DGM (in combination with an off-line intestinal model). Whilst the compendial methods with biorelevant media provided good correlation with the dissolution rates observed using the DGM/intestinal model under simulated fasted state, the quantification of simulated fed state performance changes was much more challenging using the compendial methods. Classical compendial studies using biorelevant FeSSIF and FaSSIF media could not readily discern differences in dissolution performance under fasted and fed states; however, the DGM could detect significant changes in both physical properties as well as drug release performance under fed state processing.

The structure of the title compound, {[Na(C3H7NO)3]I} n , has been redetermined at 140 (2) K. The Na+ cations lie on sites of 32 point symmetry and are linked into one-dimensional chains via bridging DMF molecules lying on mirror planes. The coordination geometry of Na+ is intermediate between octahedral and trigonal prismatic. The I− anions lie on sites of \overline{6} point symmetry between the chains.

alpha-Zirconium phosphonates derivatised with N-heterocyclic carbenes provide a versatile platform for organocatalysis and metal-catalysed transformations, including the ring-opening polymerisation of cyclic esters, and olefin metathesis and hydroformylations by surface-bound ruthenium, rhodium and iridium complexes.