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Seven commercial hop (Humulus lupulus L.) oils originating from a selection of North American hop varieties (Amarillo, Azacca, Cascade, Centennial, Chinook, Saaz, and Ahhhroma) and six homemade hop oils hydrodistilled from the same commercial hop pellets (except Ahhhroma) were compared. Seven terpenes regarded as hop oil markers (i.e., α-pinene, β-pinene, β-myrcene, β-ocimene, limonene, β-caryophyllene, and α-humulene) and methyl heptanoate were identified and quantified by GC–MS and GC-FID. The antioxidant potential of the commercial hop oil samples was evaluated using electron paramagnetic resonance (EPR) spectroscopy, while their components' antibacterial (against Aliivibrio fischeri) and enzyme (α-glucosidase and lipase) inhibition activities were screened using high-performance thin-layer chromatography (HPTLC)-based assays. A distinct feature of five of the commercial hop oils (except Saaz and Ahhhroma) was relatively high contents of β-myrcene (between 4.21 and 6.40 µg mg−1 hop oil). Azacca, Cascade, and Centennial hydrodistilled oils had perceptibly higher contents of β-caryophyllene than the rest, and most of them (except Chinook) contained relatively high amounts of α-humulene. Differences between the terpene profiles of the commercial and homemade hydrodistilled hop oils suggested that the commercial hop oils were derived from hop cones in a process different from hydrodistillation. The oils showed relatively low antioxidant potential, comparable to that of popular beers and white wines. The highest antioxidant potential was observed in Ahhhroma oil, while it was very low in Centennial oil, and no antioxidant potential was observed in Cascade and Saaz oils. The developed streamlined workflow, including parallel HPTLC-directed bioassays and HPTLC—TLC–MS Interface—SPME–GC–MS, enabled the identification of β-myrcene, dimyrcenes, β-farnesene, and 2-methylbutyl isobutyrate as anti-obesity compounds and β-farnesene, β-myrcene, and 2-methylbutyl isobutyrate as weak antibacterial hop oil components. [ABSTRACT FROM AUTHOR]

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Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Derivatives of ( E)-1-(5-alkoxybenzo[ d][1,3]oxathiol-6-yl)-3-phenylprop-2-en-1-one demonstrated exceptionally high in vitro cytotoxic activity, with IC50 values of the most active derivatives in the nanomolar range. To identify structural fragments necessary for the activity, several analogs deprived of selected fragments were prepared, and their cytotoxic activity was tested. It was found that the activity depends on combined effects of (i) the heterocyclic ring, (ii) the alkoxy group at position 5 of the benzoxathiole ring, and (iii) the substituents in the phenyl ring B. Replacement of the sulfur atom by oxygen does not influence the activity. None of the listed structural fragments alone assured high cytotoxic activity. [ABSTRACT FROM AUTHOR]

Glasses containing two different network-forming components and doped with optically active ions exhibit interesting properties. In this work, glass systems based on germanium dioxide and boron trioxide singly doped with lanthanides (Eu3+) and transition metals (Cr3+) ions are research subjects. Optical spectroscopy was the major research tool used to record excitation and emission spectra in a wide spectral range for studied systems. The emitted radiation of glasses doped with Cr3+ ions is dominated by broadband luminescence centered at 770 nm and 1050 nm (4T2 → 4A2). Interestingly, the increase of concentration of one of the oxides contributed to the detectable changes of the R-line (2E → 4A2) of Cr3+ ions. Moreover, EPR spectroscopy confirmed the paramagnetic properties of the obtained glasses. The influence of molar ratio GeO2:B2O3 on spectroscopic properties for Eu3+ ions is discussed. The intensity of luminescence bands due to transitions of trivalent europium ions as well as the ratio R/O decrease with the increase of B2O3. On the other hand, the increase in concentration B2O3 influences the increasing tendency of luminescence lifetimes for the 5D0 state of Eu3+ ions. The results will contribute to a better understanding of the role of the glass host and thus the prospects for new optical materials. [ABSTRACT FROM AUTHOR]

Phosphorus compounds present in bottom sediment collected from a drinking water reservoir have been investigated by means of 31P NMR spectroscopy and UV-Vis spectrophotometry with the use of the molybdenum blue method. Surficial sediment samples for studies were taken from different places of the reservoir, varying in depth, the distance to the shore and to the rivers as well as in the texture of the sediments. The aim of the conducted studies was to determine the main factors affecting the content of phosphorus in the sediment and to define the role of bottom sediments in supplying the water reservoir in phosphorus.The percentage of an individual phosphorus fraction in the studied sediment samples was estimated. It was ascertained that the texture of the sediment as well as the distance from the river bed are the main factors affecting the quantity of phosphorus in the sediment. [ABSTRACT FROM AUTHOR]

Studies of humification processes of sediments collected from various points of the Goczałkowice dam were con- ducted. The humic and fulvic acids were extracted from the collected sediment. For study of physico-chemical properties of humic and fulvic acids, EPR and NMR spectroscopy were used. For extracted humic and fulvic acids, concentration of free radicals and the g factor were determined with EPR. The presence of characteristic functional groups was confirmed with NMR spectroscopy. It was found that humic and fulvic acids extracted from sediment at 8 places of the Goczałkowice Reservoir are characterized by similar physico-chemical properties, which points to a similar composition of sediment in the whole reservoir. Humic acids are relatively high aromatized, have a low free radicals content and a low value of the g factor. They have condensed aromatic rings with side-aliphatic chains. However, the extracted fulvic acids are less aromatized than humic acids. They have a weakly formed aromatic core with the dominance of side-aliphatic chains. The influence of the depth of the lake on the content of oxygen functional groups in the extracted humic and fulvic acids was also observed. [ABSTRACT FROM AUTHOR]

NMR, EPR and JR spectroscopic studies of humic substances isolated from sediment and water samples have been used for characterization of humification process occurring in the Goczalkowice Reservoir. Fulvic acids (FA) were isolated from both sediment and water samples whereas humic acids (HA) only from the former due to their absence in the latter. Humic substances were studied with JR spectroscopy in order to suggest the presence of functional chemical groups. Comparison of signal intensity of the main functional groups was conducted by means of tHNIvIR techniques. The concentration of free radicals was determined with EPR. It was found that free radical concentrations of FA isolated from sediment are considerably higher than those of FA from water and HA from sediment. On the basis of the interpretation of EPR and JR spectra, the formation of transition metal complexes with humic substances was confirmed. [ABSTRACT FROM AUTHOR]