Flavonoid glycosides from endemic bulgarian astragalus aitosensis (Ivanisch.)

© 2019 The Author(s). Background: The activity and haemolytic toxicity associated with primaquine has been linked to its reactive metabolites. The reactive metabolites are thought to be primarily formed through the action of cytochrome P 450 -mediated pathways. Human erythrocytes generally are not considered a significant contributor to drug biotransformation. As erythrocytes are the target of primaquine toxicity, the ability of erythrocytes to mediate the formation of reactive oxidative primaquine metabolites in the absence of hepatic enzymes, was evaluated. Methods: Primaquine and its enantiomers were incubated separately with human red blood cells and haemoglobin. Post-incubation analysis was performed with UPLC-MS/MS to identify products of biotransformation. Results: The major metabolite detected was identified as primaquine-5,6-orthoquinone, reflecting the pathway yielding putative active and haematotoxic metabolites of primaquine, which was formed by oxidative demethylation of 5-hydroxyprimaquine. Incubation of primaquine with haemoglobin in a cell-free system yielded similar results. It appears that the observed biotransformation is due to non-enzymatic processes, perhaps due to reactive oxygen species (ROS) present in erythrocytes or in the haemoglobin incubates. Conclusion: This study presents new evidence that primaquine-5,6-orthoquinone, the metabolite of primaquine reflecting the oxidative biotransformation pathway, is generated in erythrocytes, probably by non-enzymatic means, and may not require transport from the liver or other tissues

Postharvest UV-B exposure drives changes in primary metabolism, phenolic concentration, and volatilome profile in berries of different grape (Vitis vinifera L.) varieties

BACKGROUND The ultraviolet-B (UV-B) radiation can alter grape metabolism during berry development, but little is known on the effect of postharvest UV-B exposure. In this study, we evaluated the effect of postharvest UV-B exposure on berry primary and secondary metabolites in four grapevine varieties (Aleatico, Moscato bianco, Sangiovese, and Vermentino) in order to evaluate the possibility to increase the grape quality and its nutraceutical properties. RESULTS The treatment did not significantly affect the berry primary metabolism in terms of organic acids, carbohydrates, and amino acids profile, regardless of the variety. UV-B exposure reduced the total anthocyanin content, particularly the tri-substituted and di-substituted forms in Aleatico and Sangiovese, respectively. An overall negative effect of UV-B irradiation on the flavonols profile of Aleatico, Moscato bianco, and Vermentino berries was found, whereas it enhanced the quercetin, myricetin and kaempferol concentration in Sangiovese. The free fraction of berry volatile organic compounds increased in UV-B-treated Aleatico and Moscato bianco berries, especially C-13-norisoprenoids and volatile phenols, as well as key monoterpenes, such as the linalool derivatives. However, higher concentrations of glycosylated monoterpenes and C-13-norisoprenoids were measured in Sangiovese and Vermentino berries treated with UV-B. CONCLUSION This study provides new insights on the effect of postharvest UV-B radiation on berry secondary metabolism, highlighting a different modulation between varieties and suggesting the potential use of this technique to increase some nutraceutical and quality characteristics of grape berry

Stool metabolome-microbiota evaluation among children and adolescents with obesity, overweight, and normal-weight using ¹H NMR and 16S rRNA gene profiling

Characterization of metabolites and microbiota composition from human stool provides powerful insight into the molecular phenotypic difference between subjects with normal weight and those with overweight/obesity. The aim of this study was to identify potential metabolic and bacterial signatures from stool that distinguish the overweight/obesity state in children/adolescents. Using ¹H NMR spectral analysis and 16S rRNA gene profiling, the fecal metabolic profile and bacterial composition from 52 children aged 7 to 16 was evaluated. The children were classified into three groups (16 with normal-weight, 17 with overweight, 19 with obesity). The metabolomic analysis identified four metabolites that were significantly different (p < 0.05) among the study groups based on one-way ANOVA testing: arabinose, butyrate, galactose, and trimethylamine. Significantly different (p < 0.01) genus-level taxa based on edgeR differential abundance tests were genus Escherichia and Tyzzerella subgroup 3. No significant difference in alpha-diversity was detected among the three study groups, and no significant correlations were found between the significant taxa and metabolites. The findings support the hypothesis of increased energy harvest in obesity by human gut bacteria through the growing observation of increased fecal butyrate in children with overweight/obesity, as well as an increase of certain monosaccharides in the stool. Also supported is the increase of trimethylamine as an indicator of an unhealthy state

Zamyšlení nad českou sociologií výchovy, vzdělávání a mládeže v 90. letech

879

Stiffness Models of Novel Force/Displacement Sensors

Miniaturization in field of robotics leads to use of elastic deformation where whole robotic device (precise positioning device, micro-gripper, etc.) is build from one piece of material. The disadvantage of such specific robotic devices is complicated approach to measure of their movement and acting forces. Application of influence of electromagnetic field with parallel resonating circuit seems as suitable method for sensing small deflections. This paper describes mentioned method of wireless measurement of small deflections of compliant robotic structure. Two structures of one and two-component force/displacement sensor are presented as examples using this approach. In the paper we are focused to mathematical description of stiffness models which provide basic static and dynamical properties of such structures

Environmentálne technológie v hutníctve železa a ocele/Environmental Technologies in the Iron and Steel Industry

Metallurgy, including the iron and steelmaking segments has extremely important roles in the world economy, and this creates a higher business profile for the Slovak Republic. The integral part of all business and human activities should be the ultimate protection of the environment, and this environmental protection should be independent of all society’s production and social activities. This paper identifies the current and intended environmental activities and the goals of the European Union, industry and research and development sectors, and it focuses especially on metallurgical and environmental interaction. Our aim is to bring the current status and trends of iron and steel metallurgy to the closer attention of the scientific community, and therefore we examine these trends in relationship to iron and steel metallurgy and the environmental protective aspects in technology and innovation

The effect of soil risk element contamination level on the element contents in Ocimum basilicum L.

Red basil (Ocimum basilicum L.) cv. Red Rubin was cultivated in model pot experiment in the soil amended by arsenic, cadmium and lead solutions in stepwise concentrations representing the soil concentration levels of former mining area in the vicinity of Příbram, Czech Republic. The element levels added to the soil reached up to 40 mg Cd, 100 mg As, and 2000 mg Pb per kg of soil. Moreover, essential macro-and microelements as well as cyanidine contents were investigated to assess their potential interactions with the risk elements. The extractable element portions in soils determined at the end of vegetation period differed according to the individual elements. Whereas the plant-available (extractable with 0.11M CH3COOH) content of Cd represented 70-100% of the added Cd, the mobile portion of Pb did not exceed 1%. The risk element content in plants reflected the increasing element contents in soil. The dominant element portions remained in plant roots indicating the limited translocation ability of risk elements to the aboveground biomass of this plant species. Although the risk element contents in amended plants significantly increased, no visible symptoms of phytotoxicity occurred. However, the effect of enhanced risk element contents on the essential element uptake was assessed. Considering inter-element relationships, elevated sulphur levels were seen in amended plants, indicating its possible role of phytochelatin synthesis in the plants. Moreover, the molybdenum contents in plant biomass dropped down with increasing risk element uptake by plants confirming As-Mo and Cd-Mo antagonism. The increasing content of cyanidine in the plant biomass confirmed possible role of anthocyanins in detoxification mechanism of risk element contaminated plants and suggested the importance of anthocyanin pigments for risk element tolerance of plants growing in contaminated areas

Flavonoid Glycosides from Endemic Bulgarian <i>Astragalus aitosensis</i> (Ivanisch.)

Astragalus is a very interesting plant genus, well-known for its content of flavonoids, triterpenes and polysaccharides. Its secondary metabolites are described as biologically active compounds showing several activities, e.g., immunomodulating, antibacterial, antiviral and hepatoprotective. This inspired us to analyze the Bulgarian endemic A. aitosensis (Ivanisch.) to obtain deeper information about its phenolic components. We used extensive chromatographic separation of A. aitosensis extract to obtain seven phenolic compounds (1&#8211;7), which were identified using combined LC-MS and NMR spectral studies. The 1D and 2D NMR analyses and HR-MS allowed us to resolve the structures of known compounds 5&#8211;7 as isorhamnetin-3-O-robinobioside, isorhamnetin-3-O-(2,6-di-O-&#945;-rhamno-pyranosyl-&#946;-galactopyranoside), and alangiflavoside, respectively, and further comparison of these spectral data with available literature helped us with structural analysis of newly described flavonoid glycosides 1&#8211;4. These were described in plant source for the first time