Uracil as an index of lactic acid bacteria contamination of tomato products

Antihypertensive effects of abalone viscera fermented with Lactiplantibacillus pentosus SN001 via angiotensin-converting enzyme inhibition

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L. pentosus SN001-fermented abalone viscera reduced blood pressure in vivo.

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L. pentosus SN001-fermented abalone viscera did not affect rat blood composition.

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L. pentosus SN001-fermented abalone viscera had a good safety profile.

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Uracil was identified from L. pentosus SN001-fermented abalone viscera.

Abalone viscera, which accounts for more than 20% of body weight, is typically discarded. With increases in abalone aquaculture production, novel uses for abalone viscera are needed. Here, we evaluated the effects of abalone viscera fermented with Lactiplantibacillus pentosus SN001 on angiotensin-converting enzyme (ACE) activity and blood pressure elevation in spontaneously hypertensive rats. The fermented product significantly reduced systolic blood pressure compared with the control. There were no significant differences in blood glucose, triglyceride, total cholesterol, or high-density lipoprotein cholesterol levels; alanine aminotransferase activity; and aspartate aminotransferase activity between the fermented product and control groups. Uracil was isolated and identified from the fermented product. Uracil may be the active component. Overall, L. pentosus SN001-fermented abalone viscera showed sustained inhibitory effects on blood pressure elevation but did not alter blood components after long-term intake. These results provide insights into the safety of L. pentosus SN001-fermented abalone viscera as a food product.

Detection of microbial contamination based on uracil-selective synthetic receptors

The here presented work is focused on the development of a method for detection of microbial contamination of food based on uracil-selective synthetic receptors. Because uracil may serve as an indicator of bacterial contamination, its selective and on-site detection may prevent spreading of foodborne diseases. The synthetic receptors were created by molecular imprinting. Molecularly imprinted polymers for selective uracil isolation were prepared by a non-covalent imprinting method using dopamine as a functional monomer. Detection of isolated uracil was performed by capillary electrophoresis with absorption detection (λ - 260 nm). The conditions of preparation of molecularly imprinted polymers, their binding properties, adsorption kinetics and selectivity were investigated in detail. Furthermore, the prepared polymer materials were used for selective isolation and detection of uracil from complex samples as tomato products by miniaturized electrophoretic system suggesting the potential of in situ analysis of real samples.

Synthesis of heterocyclic scaffolds through 6-aminouracil-involved multicomponent reactions

There is a wide range of multicomponent reactions that include 6-aminouracil in the synthesis of heterocyclic compounds. This review highlights the advances in the use of 6-aminouracil in the synthesis of various organic compounds.

Antihypertensive Effect of a Combination of Uracil and Glycerol Derived from Lactobacillus plantarum Strain TWK10-Fermented Soy Milk

We previously demonstrated that angiotensin-converting enzyme (ACE) could be inhibited by soy milk that had been fermented with the Lactobacillus plantarum strain TWK10, suggesting great potential for the development of antihypertensive products. In this work, the bioactive ACE inhibitors in TWK10-fermented soy milk water extracts were isolated, and a combination of uracil and glycerol (CUG) was identified as one of the ACE inhibitors. We then examined the physiological effects of CUG treatment in short-term and long-term studies using spontaneously hypertensive rats (SHRs) as an experimental model. The results revealed that the fermented soy milk extracts and CUG decreased blood pressure by 11.97 ± 3.71 to 19.54 ± 9.54 mmHg, 8 h after oral administration, and exhibited antihypertensive effects in SHRs in a long-term study. In addition, CUG was shown to decrease blood pressure by suppressing either the renin activity or the ACE activity and, thus, decreasing the downstream vasoconstricting peptide angiotensin II and the hormone aldosterone. CUG also promoted nitric oxide production, resulting in vasodilation and further improvement to hypertension. This important finding suggests that TWK10-fermented soy milk and its functional ingredients, uracil and glycerol, exhibit antihypertensive effects via multiple pathways and provide a healthier and more natural antihypertensive functional food.

Hydrothermal synthesis, experimental and theoretical characterization of a novel cocrystal compound in the 2:1 stoichiometric ratio containing 6-methyluracil and dipicolinic acid

This paper reports the hydrothermal synthesis, experimental and theoretical studies of a novel cocrystal compound in the 2:1 stoichiometric ratio of 6-methyluracil (6mu) and dipicolinic acid (pydcH(2)) formulated as [6mu](2)[pydcH(2)] (1), for the first time. DFT calculations were performed to access the most possible geometry of the title cocrystal compound. All calculations were carried out with the B3LYP hybrid density functional level and 6-311+G(d,p) basis sets. The vibrational frequencies together with the (1)H and (13)C NMR chemical shifts have been calculated on the fully optimized geometry of 1. The theoretical results are in good agreement with the experimental and solution data. The theoretical, solution, and experimental (elemental analysis, mass spectrometry, FTIR, (1)H and (13)C NMR spectroscopies) results confirmed our proposed structure for 1 in the 2:1 stoichiometric ratio of 6mu and pydcH(2), respectively. The protonation and equilibrium constants of 6mu and pydcH(2) and constituent systems were determined by potentiometric studies and the corresponding distribution diagrams depicted.

Chemical markers for the evaluation of raw material hygienic quality in egg products

The aim of this research was to study uracil and lactic and acetic acids as chemical markers for hygienic quality evaluation of raw material in liquid pasteurized egg products. Uracil, absent in sound whole eggs, was formed in raw and pasteurized egg products as a consequence of high microbial contamination (>10(6) cfu/g) after a sufficient lag time, remaining stable at 4 degrees C but disappearing after 7 days of storage at 25 degrees C. Both lactic and acetic acids, starting from initial values of 1-7 mg/kg dry matter, presented trends similar to that of uracil; however, acetic acid never decreased during the storage of raw egg products. With few exceptions, all three metabolites were produced by Enterobacter cloacae, Escherichia coli, Morganella morganii, Serratia liquefaciens, Aeromonas hydrophyla, Pseudomonas fluorescens, Enterococcus avium, and Enterococcus faecalis, separately inoculated in whole egg samples. Uracil seems to be the most sensible marker, with a suggested limit corresponding to the detectable level.