Bogumiła Kupcewicz

Copper(II) complexes with derivatives of pyrazole as potential antioxidant enzyme mimics

A series of six mononuclear Cu(II) complexes with pyrazole-based ligands: 5-(2-hydroxybenzoyl)-3-methyl-1-(2-pyridinyl)-1H-pyrazol-4-phosphonic acid dimethyl ester (1a), 5-(2-hydroxyphenyl)-3-methyl-1-(2-pyridylo)-1H-pyrazole-4-carboxylic acid methyl ester (1b) and 1-benzothiazol-2-yl-5-(2-hydroxyphenyl)-3-methyl-1H-pyrazole-4-carboxylic acid methyl ester (1c) were characterized regarding to electrochemical and antioxidant properties. All complexes exhibit suitable Cu(II)/Cu(I) redox potential (E1/2) to act as antioxidant enzymes mimic. The five of these complexes were found to be trifunctional enzyme mimics possessing SOD, CAT and GPx-like catalytic activities. Moreover, Cu(II) complexes were capable to decrease ROS level in melanoma cells and observed effects were not merely a reflection of cytotoxicity.

Content of selected heavy metals in the organs of fish from Znin Duze Lake

Fish species constituting the majority of the fish population ofnin Du?e Lake were selected for the investigations. They included: roach, white bream, common bream and perch. The largest amounts of detected metals accumulated in the liver and gills, and the lowest amounts occurred in muscle, except copper which had the lowest concentration in the gills. A bifactor analysis of variance revealed that the average concentrations of the elements in different organs differed significantly, but only in a few cases the average contents of mineral components in the same organ for different species differed significantly. The analysis of the dependence of the content of elements in different organs and the fish body length indicated a positive correlation for Cu, Fe and Ni, and a negative correlation for Zn and Mn in muscle. The analysis of the bioaccumulation coefficient revealed that the largest tendency to accumulate in muscle is displayed by zinc and iron, manganese and copper accumulate the least.

The synthesis, lipophilicity and cytotoxic effects of new ruthenium(II) arene complexes with chromone derivatives.

A series of arene ruthenium(II) complexes with the general formula [(η(6)-arene)Ru(L)X2] (where arene=p-cymene, benzene, hexamethylbenzene or mesitylene, L=aminoflavone or aminochromone derivatives and X=Cl, I) were synthesized and characterized by elemental analysis, MS, IR and (1)H NMR spectroscopy. The stability of the selected complexes was assessed by UV-Vis spectroscopy in 24-hour period. The lipophilicity of the synthesized complexes was determined by the shake-flask method, and their cytotoxicity evaluated in vitro on patient-derived melanoma populations. The most active complexes against melanoma cells contain 7-aminoflavone and 6-aminoflavone as a ligand. The relationship between the cytotoxicity of all the obtained compounds and their logP values was determined and briefly analyzed with two different patterns observed.

Impact of Different Fishing Seasons on the Fatty Acids Profile, Cholesterol Content, And Fat in the Muscles of Perch, Perca Fluviatils L. from the Włocławski Reservoir (Central Poland)

Impact of Different Fishing Seasons on the Fatty Acids Profile, Cholesterol Content, And Fat in the Muscles of Perch, Perca Fluviatils L. from the Włocławski Reservoir (Central Poland) The aim of the study was to compare the fatty acids profile, fat content, and total cholesterol in the muscles of female perch, Perca fluviatilis L., caught in fall and spring. The group of fish examined was comprised of perch caught in the Włocławski Reservoir in December 2005 and June 2006. Analysis indicated that the muscles of the fish caught in fall had higher total cholesterol and fat content (53.91 mg 100 g-1 and 2.17%, respectively) in comparison with the level of these parameters in the muscles of perch caught in spring (44.74 mg 100 g-1 and 1.94%, respectively). In both seasons, the main saturated fatty acid (SFA) was C16:0, the monounsaturated fatty acids (MUFA) were dominated by C18:1 n-6, and the highest percentage of polyunsaturated fatty acids (PUFA) was of C20:5 n-3. The total SFA and PUFA was higher in the muscles of perch caught in fall at 47.53 and 28.65%, respectively, in contrast to the values of these acids in spring, which were 43.02% and 21.73%, respectively. Total MUFA in fall (23.83%) was lower than in spring (32.24%). Wpływ Różnych Sezonów Odłowu na Profil Kwasów Tłuszczowych, Zawartość Cholesterolu Oraz Tłuszczu w Mięsie Okonia (Perca Fluviatils L.) ze Zbiornika Włocławskiego (Centralna Polska) Celem badań było porównanie profilu kwasów tłuszczowych, zawartości tłuszczu i cholesterolu całkowitego w mięsie samic okoni, Perca fluviatilis L. pomiędzy wiosną i jesienią. Grupę badawczą stanowiły okonie ze Zbiornika Włocławskiego pozyskane w grudniu 2005 roku i czerwcu 2006 roku. Analiza wykazała, że w mięsie ryb odłowionych jesienią było większe stężenie cholesterolu całkowitego (53,91 mg 100 g-1) i tłuszczu (2,17%), w porównaniu z poziomem tych parametrów w mięsie okoni pozyskanych wiosną, kiedy zawartość cholesterolu całkowitego wynosiła 44,74 mg 100 g-1, a tłuszcz stanowił 1,94%. W obu sezonach głównym kwasem spośród nasyconych kwasów tłuszczowych (SFA) był C16:0, w grupie monoenowych kwasów tłuszczowych (MUFA) dominował C18:1 n-6, a spośród polienowych kwasów (PUFA) największy procent stanowił C20:5 n-3. Suma SFA i PUFA była wyższa w mięsie okoni pozyskanych jesienią i stanowiła odpowiednio 47,53 i 28,65%, w przeciwieństwie do wartości tych kwasów u ryb odłowionych wiosną, u których SFA stanowiło 43,02%, a PUFA 21,73%. Suma MUFA jesienią (23,83%) była niższa niż wiosną (32,24%).

Chemometric analysis of antioxidant properties of herbal products containing Ginkgo biloba extract

Ginkgo biloba extract is a popular ingredient in pharmaceutical formulations. The level of bioactive compounds determines final antioxidant activity of an extract and its therapeutic efficiency. The aim of the project was to assess phytopharmaceuticals containing Ginkgo extracts in terms of their chemical characteristic and antioxidant activity using selected chemometric methods. The aim of the study was also to investigate whether the antioxidant activity of phytopharmaceuticals can be successfully predicted based on their chromatograms. Total polyphenol content and antioxidant activity of methanolic Ginkgo extracts were determined using a spectrophotometric technique. Comparative chemometric analysis of investigated pharmaceutical formulations was carried out using hierarchical and non-hierarchical segmentation algorithms. Samples of herbal drug products were clearly separated from samples of dietary supplements. A tree regression method was used to predict the antioxidant activity of pharmaceuticals based on the chromatographic description. The correlations between the predicted (by regression model) and experimental values of IC50 for training and testing subset were 0.960 and 0.949, respectively. The chemometric techniques, combined with instrumental analysis, could improve and simplify the quality control methods of herbal products. The antioxidant activity, predicted on the basis of chromatograms, may be one of measures of final product quality.

Structure–cytotoxic activity relationship of 3-arylideneflavanone and chromanone (E,Z isomers) and 3-arylflavones

The E,Z-isomers of 3-arylidene substituted flavanone, chromanone and 3-aryl substituted flavone derivatives were tested in vitro for their cytotoxic activity against three cancer cell lines (HL-60, NALM-6, WM-115) and normal cell line (HUVEC). It was observed that substitution at C3 position led to significant enhance in cytotoxicity. Isomeric configuration of 3-arylideneflavanones had an influence on the cytotoxic potential. Multiple regression analysis combined with variable selection by genetic algorithm was used to model relationships between molecular descriptors and the cytotoxic activity. The most accurate QSAR models were based on a combination between energy of LUMO, experimental value of logP and partial charge on carbonyl oxygen (δO2).

Simultaneous determination of ciprofloxacin hydrochloride and hydrocortisone in ear drops by high performance liquid chromatography

The aim of the study was to design and validate a reversed phase high performance liquid chromatography method for the separation and quantification of two active pharmaceutical ingredients (ciprofloxacin hydrochloride, hydrocortisone) and a preservative (benzyl alcohol) in ear drops. Effective separation of the examined compounds was achieved on a GraceSmart™ RP 18 column (150 mm × 4.6 mm, 5 μm) with gradient elution and a diode array detector. The total assay run time was 25 min. Analytical method validation assays were performed. Validation parameters used for the evaluation were: specificity, linearity, trueness, precision (repeatability and reproducibility), limit of detection and limit of quantitation. Results of the validation procedure (high recoveries, good standard deviations, no interfering peaks at the retention times corresponding to the analytes) confirm that the developed chromatographic method can be applied for routine analysis of ear drops.

Chemometric analysis of fatty acids profile of bream (Abramis brama), ruffe (Gymnocephalus cernua) and perch (Perca fluviatilis) meat from Lake Gopło and Włocławski Dam Reservoir

The 18 fatty acid profiles have been determined in 63 samples of muscles from three freshwater fish species: bream, ruffe and perch by gas chromatography method. The fish were collected in natural condition from two reservoirs located in central Poland: Lake Goplo and Wloclawski Reservoir. A chemometric study with the use of hierarchical cluster analysis (HCA), principal component (PCA) and stepwise linear discrimination analysis (LDA) was applied to characterize, classify and differentiate collected samples. The chemometric techniques by using fatty acids content as descriptors allow clearly distinguish 6 groups according to fish species and their geographical origin.

Quantitative relationships between structure and cytotoxic activity of flavonoid derivatives. An application of Hirshfeld surface derived descriptors.

Quantitative relationships between the structure and cytotoxic activity of series flavonoid derivatives were examined. The first regression-based model, developed for 18 flavanone-2-pyrazoline hybrids, involved two interpretable descriptors: a Mor04v and partial atomic charge. The second model, developed for structurally diverse set of compounds, was based on descriptors derived from Hirshfeld surface analysis. This model suggests that cytotoxic activity of compounds can be successfully predicted based on a fraction of H⋯H contacts and a fraction of interactions involving a halogen atom. For non-halogen derivatives, the data reveal that cytotoxic activity is inversely proportional to the percentage of O⋯H and N⋯H close contacts to Hirshfeld surface, while directly proportional to the percentage of H⋯H interactions. Chlorine (1k) and bromine (1l) derivatives of compounds, containing flavanone fused with N-methyl-2-pyrazoline, exhibited high cytotoxic potential against HL-60 cancer cell line (IC50<10μM). The cytotoxicity of 1k and 1l towards normal cells (HUVEC) was 10 and 25-fold lower, respectively.

Implementation of chemometric techniques for evaluation of antioxidant properties of Camellia sinensis extracts

In this study, antioxidant properties of commercial green teas and dietary supplements containing Camellia sinensis extracts were evaluated. Extracts were examined using two antioxidant assays (DPPH· radical method and ABTS·+ cation radical method). A Folin-Ciocalteu assay was used to evaluate the total polyphenol content in the extracts. In order to compare and characterize the investigated Camellia sinensis extracts, chemometric techniques based on fingerprint chromatograms, antioxidant activity and total polyphenol content were applied. Application of chemometric methods allowed for reduction of multidimensionality of the data set and grouped the samples into differentiable clusters. The relationship between the antioxidant activity and total polyphenol content was also assessed. The results indicated that extracts with the higher polyphenolic content exhibited the stronger antiradical activity against both DPPH· radicals and ABTS·+ cation radicals. The multivariate calibration technique (such as a tree regression algorithm) can be a useful tool for rapid determining the antioxidant activity of a herbal product based on its fingerprint chromatogram