68 research outputs found
DFT study of the radical scavenging activity of isoxanthohumol, humulones (Ī±-acids), and iso-Ī±-acids from beer
Humulones and iso-humulones are potent natural antioxidants found in beer. In this study, density functional theory (DFT) method was applied for elucidating the structure-antioxidant activity relationship and molecular mechanism of antioxidant activity of eight bioactive humulones previously identified in different beer samples: isoxanthohumol, (R)- and (S)-adhumulone, cis- and trans-iso-adhumulone, cis- and trans-iso-n-humulone, and desdimethyl-octahydro-iso-cohumulone. The calculated bond dissociation enthalpies (BDEs) suggest that desdimethyl-octahydro-iso-cohumulone was the most potent compound with BDEs 5.1 and 23.9 kJ/mol lower compared to the values for resveratrol in gas phase and water, respectively. The enolic āOH is the most reactive site for hydrogen atom transfer (HAT). The presence of Ī²-keto group with respect to enolic āOH diminishes the HAT potency via the formation of a strong intramolecular hydrogen bond. Another common antioxidant mechanism, single electron transfer followed by proton transfer (SET-PT), is only feasible for isoxanthohumol. The results of this study indicate a strong correlation between the increased antioxidant activity of beer products and the higher content of reduced iso-Ī±-acids
Supplementary material for the article: KrstiÄ, Ä.; VukojeviÄ, V.; MutiÄ, J.; FotiriÄ AkÅ”iÄ, M.; LiÄina, V.; MilojkoviÄ-Opsenica, D.; TrifkoviÄ, J. Distribution of Elements in Seeds of Some Wild and Cultivated Fruits. Nutrition and Authenticity Aspects. Journal of the Science of Food and Agriculture 2019, 99 (2), 546ā554. https://doi.org/10.1002/jsfa.9213
Supplementary material for: [https://doi.org/10.1002/jsfa.9213]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/343]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3200
Supplementary material for the article: KrstiÄ, Ä.; VukojeviÄ, V.; MutiÄ, J.; FotiriÄ AkÅ”iÄ, M.; LiÄina, V.; MilojkoviÄ-Opsenica, D.; TrifkoviÄ, J. Distribution of Elements in Seeds of Some Wild and Cultivated Fruits. Nutrition and Authenticity Aspects. Journal of the Science of Food and Agriculture 2019, 99 (2), 546ā554. https://doi.org/10.1002/jsfa.9213
Supplementary material for: [https://doi.org/10.1002/jsfa.9213]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/343]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3200
Phenolic Composition Influences the Health-Promoting Potential of Bee-Pollen
Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3775
Aromatic Guanylhydrazones for the Control of Heme-Induced Antibody Polyreactivity
In a healthy immune repertoire, there exists a fraction of polyreactive antibodies that can bind to a variety of unrelated self- and foreign antigens. Apart from naturally polyreactive antibodies, in every healthy individual, there is a fraction of antibody that can gain polyreactivity upon exposure to porphyrin cofactor heme. Molecular mechanisms and biological significance of the appearance of cryptic polyreactivity are not well understood. It is believed that heme acts as an interfacial cofactor between the antibody and the newly recognized antigens. To further test this claim and gain insight into the types of interactions involved in heme binding, we herein investigated the influence of a group of aromatic guanylhydrazone molecules on the heme-induced antibody polyreactivity. From the analysis of SAR and the results of UV-vis absorbance spectroscopy, it was concluded that the most probable mechanism by which the studied molecules inhibit heme-mediated polyreactivity of the antibody is the direct binding to heme, thus preventing heme from binding to antibody and/or antigen. The inhibitory capacity of the most potent compounds was substantially higher than that of chloroquine, a well-known heme binder. Some of the guanylhydrazone molecules were able to induce polyreactivity of the studied antibody themselves, possibly by a mechanism similar to heme. Results described here point to the conclusion that heme indeed must bind to an antibody to induce its polyreactivity, and that both pi-stacking interactions and iron coordination contribute to the binding affinity, while certain structures, such as guanylhydrazones, can interfere with these processes
Comparison of nutritional properties and antioxidant activity of garlic and its fermented product
Over the past few years, fermented garlic and its extracts have been increasingly used in cooking
and in the daily diet due to their specific taste, nutritional composition and health benefits. The
fermentation process is performed by heat treatment of garlic with controlled humidity for a
longer period of time. During fermentation, chemical reactions and transformations such as
Maillard reactions and caramelization reactions cause the changes in taste, nutritional
composition, content of macro- and microelements as well as the content of phenolic compounds
and antioxidant activity of garlic. In this paper, samples of garlic and fermented garlic were
analyzed and the content of phenolic compounds, antioxidant activity, macro- and microelements
as well as nutritional composition were compared. The content of Ca, K, Mg, Na, Mn, Cu, Zn,
and W increased, while the content of Fe, Al, Cr, Ni, Mo, Hg and Pb decreased during
fermentation. The water content decreased during the fermentation process, while the sugar and
carbohydrate content increased significantly as a result of thermal decomposition of the polyand
oligosaccharides (fructan and other complex polysaccharides). Accordingly, the energy
value of fermented garlic is higher than that of fresh garlic. The content of total phenolic
compounds is higher in the fermented sample compared to fresh one, indicating different
chemical transformations of secondary metabolites during the fermentation process. As a
measure of antioxidant activity, two assays were performed: DPPH and FIC and both showed
higher activity of fermented garlic, which is positively correlated with the higher content of
phenolic compounds in the sample.Abstract: [https://cherry.chem.bg.ac.rs/handle/123456789/5232
Supplementary material for the article: SaviÄ, N. D.; Vojnovic, S.; GliÅ”iÄ, B. Ä.; Crochet, A.; Pavic, A.; JanjiÄ, G. V.; PekmezoviÄ, M.; Opsenica, I. M.; Fromm, K. M.; Nikodinovic-Runic, J.; et al. Mononuclear Silver(I) Complexes with 1,7-Phenanthroline as Potent Inhibitors of Candida Growth. Eur. J. Med. Chem. 2018, 156, 760ā773. https://doi.org/10.1016/j.ejmech.2018.07.049
Supplementary data for: [https://doi.org/10.1016/j.ejmech.2018.07.049]Research data for this article: [https://www.ccdc.cam.ac.uk/structures/search?id=doi:10.5517/ccdc.csd.cc1zdr7c&sid=DataCite]Research data for this article: [https://www.ccdc.cam.ac.uk/structures/search?id=doi:10.5517/ccdc.csd.cc1zdr6b&sid=DataCite]Research data for this article: [https://www.ccdc.cam.ac.uk/structures/search?id=doi:10.5517/ccdc.csd.cc1zdr59&sid=DataCite]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2213]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/2993
Gis techology in regional recognition of the distribution pattern of multifloral honey: the chemical traits in Serbia
GIS is a computer-based system to input, store, manipulate, analyze and output spatially referenced data. There is a huge range application of GIS that generally sets out to fulfill: mapping, measurement, monitoring, modeling and management. In this study, GIS technology was used for the regional recognition of origin and distribution patterns of multifloral honey chemical traits in Serbia. This included organizing and analyzing the spatial and attributive data of 164 honey samples collected from different regions of Serbia during the harvesting season of 2009. Multifloral honey was characterized in regards to mineral composition, sugar content and basic physicochemical properties. The kriging method of Geostatistical Analyst was used for interpolation to predict values of a sampled variable over the whole territory of Serbi
Comparison of nutritional properties and antioxidant activity of garlic and its fermented product
Over the past few years, fermented garlic and its extracts have been increasingly used in cookingand in the daily diet due to their specific taste, nutritional composition and health benefits. Thefermentation process is performed by heat treatment of garlic with controlled humidity for alonger period of time. During fermentation, chemical reactions and transformations such asMaillard reactions and caramelization reactions cause the changes in taste, nutritionalcomposition, content of macro- and microelements as well as the content of phenolic compoundsand antioxidant activity of garlic. In this paper, samples of garlic and fermented garlic wereanalyzed and the content of phenolic compounds, antioxidant activity, macro- and microelementsas well as nutritional composition were compared. The content of Ca, K, Mg, Na, Mn, Cu, Zn,and W increased, while the content of Fe, Al, Cr, Ni, Mo, Hg and Pb decreased duringfermentation. The water content decreased during the fermentation process, while the sugar andcarbohydrate content increased significantly as a result of thermal decomposition of the polyandoligosaccharides (fructan and other complex polysaccharides). Accordingly, the energyvalue of fermented garlic is higher than that of fresh garlic. The content of total phenoliccompounds is higher in the fermented sample compared to fresh one, indicating differentchemical transformations of secondary metabolites during the fermentation process. As ameasure of antioxidant activity, two assays were performed: DPPH and FIC and both showedhigher activity of fermented garlic, which is positively correlated with the higher content ofphenolic compounds in the sample.Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5230
Comparison of nutritional properties and in-vitro antioxidant activity of organically grown garlic and its fermented product
Over the past few years, fermented garlic and its extracts have been increasingly used in cooking and in the daily diet due to their specific taste, nutritional composition and health benefits. The fermentation process is performed by heat treatment of garlic with controlled humidity for a longer period of time. During fermentation, chemical reactions and transformations such as Maillard reactions and caramelization reactions cause the changes in taste, nutritional composition, content of macro- and microelements as well as the content of phenolic compounds and antioxidant activity of garlic. In this paper, samples of garlic and fermented garlic were analyzed and the content of phenolic compounds, antioxidant activity, macro- and microelements as well as nutritional composition were compared. The content of Ca, K, Mg, Na, Mn, Cu, Zn, and W increased, while the content of Fe, Al, Cr, Ni, Mo, Hg and Pb decreased during fermentation. The water content decreased during the fermentation process, while the sugar and carbohydrate content increased significantly as a result of thermal decomposition of the poly- and oligosaccharides (fructan and other complex polysaccharides). Accordingly, the energy value of fermented garlic is higher than that of fresh garlic. The content of total phenolic compounds is higher in the fermented sample compared to fresh one, indicating different chemical transformations of secondary metabolites during the fermentation process. As a measure of antioxidant activity, two assays were performed: DPPH and FIC and both showed higher activity of fermented garlic, which is positively correlated with the higher content of phenolic compounds in the sample.Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5246
- ā¦