Purity assessment of recombinant human granulocyte colony-stimulating factor in finished drug product by capillary zone electrophoresis.

Current methods for determination of impurities with different charge-to-volume ratio are limited especially in terms of sensitivity and precision. The main goal of this research was to establish a quantitative method for determination of impurities with charges differing from that of recombinant human granulocyte colony-stimulating factor (rhG-CSF, filgrastim) with superior precision and sensitivity compared to existing methods. A CZE method has been developed, optimized, and validated for a purity assessment of filgrastim in liquid pharmaceutical formulations.

A comparison of the nutritional value and food safety of organically and conventionally produced wheat flours.

Growing interest in organic agriculture has prompted this study aiming to evaluate nutritional content of wheat flours originating from organic and conventional production systems. Obtained results showed that organic samples had significantly lower protein content and lower levels of Ca, Mn and Fe compared to conventional samples. Protein digestibility and levels of K, Zn and Mo were significantly higher in organic than in conventional wheat flours.

Interference of selected flavonoid aglycons in platelet aggregation assays.

Background: Flavonoids are widely distributed across the plant kingdom and are therefore common ingredients in an everyday diet. Some flavonoids have a potential to affect platelet aggregation; most often antiaggregatory effects of flavonoids are observed. The objective of this research was to evaluate the in vitro effect of a selected set of flavonoids on platelet aggregation in whole blood.

Evaluation of antiaggregatory activity of flavonoid aglycone series.

Background: Among natural compounds, present in every day diet, flavonoids have shown beneficial effect in prevention of cardiovascular diseases that can be attributed, at least partially to the described antiaggregatory activity i.e. antiplatelet effects of flavonoids.

Effect of natural biostimulants on yield and nutritional quality: an example of sweet yellow pepper (Capsicum annuum L.) plants.

Background: Modifications in growing techniques can affect the yield and nutritional quality of various cultivated plant species. Owing to its high nutritional value, pepper (Capsicum annuum L.) was used in this study as a model plant to investigate the effect of natural biostimulants on yield and fruit quality parameters under conditions of reduced fertilisation.

Chemical composition of the ethanolic propolis extracts and its effect on HeLa cells.

Ethnopharmacological Relevance: Propolis is a resinous hive product collected by honeybees from various plant sources. It is widely used in traditional medicine and is reported to have a broad spectrum of pharmacological effects (antibacterial, antihepatoxic, antioxidative, anti-inflammatory, etc.).

Recent advances in the application of high performance liquid chromatography in the analysis of polyphenols in wine and propolis.

Wine and propolis are among the richest sources of polyphenolics. Flavonoids and phenolic acids are main pharmacological components whose benefits have been shown in numerous reports. This paper presents a review of the latest applications of HPLC for determination of polyphenolics in propolis and wine.

From functional food to medicinal product: systematic approach in analysis of polyphenolics from propolis and wine.

In the last decade we have been working on standardization of propolis extract and determination of active constituents of wine those are rich in polyphenolics and have nutritional as well as therapeutic value. Here we are summarizing our results and providing overview on systematic approach how to analyse natural products rich in flavonoids and phenolic acids.Chromatographic methods (thin layer chromatography and high performance liquid chromatography) were used for identification, quantification, and characterization of individual flavonoid or phenolic acid.

The synthesis and antimicrobial activity of some 4-hydroxycoumarin derivatives.

Due to exceptional reactivity of 4-hydroxycoumarin, the synthesis of new coumarin derivatives of dimer and tetramer type has been carried out. The synthesis was carried out from 4-hydroxycoumarin and various aromatic aldehydes. In this way, compounds of the dimer 3,3'-(benzilidene)bis (4-hydroxycoumarin) type, as well as of the tetramer 3,3',3'',3'''-(1,4-dimethylenphenyl)tetra (4-hydroxycoumarin) type were prepared.

QSAR study of antioxidant activity of wine polyphenols.

Quantitative structure activity relationships (QSAR) were obtained describing the antioxidant activity of the main pharmacologically active polyphenols of wine, using molecular properties and descriptors derived from the 2D and 3D representations of molecules. The best models for the prediction of the ability to scavenge the ABTS radical cation were obtained by polynomial regression analysis using zero-order connectivity index and molar refractivity. Statistically, significant models for lipid peroxidation inhibiting effects of flavonoids were obtained by polynomial and multiple regression using lipophilicity, Balaban index, Balaban-type index and 3D GETAWAY descriptor.

Evaluation of antioxidative activity of Croatian propolis samples using DPPH* and ABTS*+ stable free radical assays.

Propolis is one of the richest sources of plant phenolics (flavonoids and phenolic acids), which are widely recognized as rather strong antioxidants. The aim of our work was to use colored stable free radical (DPPH* and ABTS*+) spectrophotometric and thin-layer chromatographic (TLC) assays to study the antioxidative behavior of the phenolics (caffeic acid, galangin and pinocembrin) most commonly present in Croatian propolis samples obtained from different Croatian regions. We propose a mathematical model providing a more sophisticated interpretation of the obtained results and a new parameter named antioxidative efficiency (AOE) is introduced.

QSAR study of antimicrobial activity of some 3-nitrocoumarins and related compounds.

A new class of antimicrobial agents, 3-nitrocoumarins and related compounds, has been chosen as a subject of the present study. In order to explore their activity and molecular properties that determine their antimicrobial effects, QSAR models have been proposed. Most of the 64 descriptors used for the development were extracted from semiempirical and density functional theory (DFT) founded calculations.

In vivo study of propolis supplementation effects on antioxidative status and red blood cells.

In vivo study has been conducted on 47 healthy women and men in order to investigate whether daily intake of powdered propolis extract during 30 days has any influence on the following blood parameters: activity of superoxide dismutase, glutathione peroxidase and catalase, concentration of plasma malondialdehyde, total cholesterol, low- and high-density lipoprotein cholesterol, triglycerides, glucose, uric acid, ferritin and transferrin, together with routine red blood cell parameters. The effect of daily propolis intake seems to be time and gender related. For the men test group after the initial 15 days of propolis treatment, 23.

Novel approach to evolutionary neural network based descriptor selection and QSAR model development.

Capability of evolutionary neural network (ENN) based QSAR approach to direct the descriptor selection process towards stable descriptor subset (DS) composition characterized by acceptable generalization, as well as the influence of description stability on QSAR model interpretation have been examined. In order to analyze the DS stability and QSAR model generalization properties multiple random dataset partitions into training and test set were made. Acceptability criteria proposed by Golbraikh et al.

Evaluation of novel sample identification approach based on chromatographic fingerprint set correlation homogeneity analysis.

Instead of usual rationale for chromatographic fingerprint based sample identification which relies upon visual inspection or principal component analysis of raw or aligned chromatograms novel nonparametric statistical measure of fingerprint set homogeneity is proposed. Randomization test is applied for significance analysis of fingerprint set homogeneity while average maximum crosscorrelation is used as a merit function. Chromatogram sets generated by random selection from standard and unknown sample chromatogram collections are compared with respect to merit function values with set of chromatograms that represents standard and/or unknown sample.

Lipophilicity study of salicylamide.

Molecular lipophilicity was studied using salicylamide as a model drug. Log P value for the target compound was experimentally determined by the shake-flask method and calculated using nine different computer programs based on atom/fragment contributions, structural parameters, atom-type electrotopological-state indices and neural network modeling, or topological structure descriptors. Our analysis demonstrates good agreement between the experimentally observed log P value of salicylamide and the value calculated by the CSLogP program, based on topological structure descriptors and electrotopological indices.