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The application of High Performance Thin Layer Chromatography (HPTLC)-based non-targeted metabolomics as a holistic approach to compare fingerprints of metabolite changes during Artemisia annua development is described. Images of HPTLC chromatograms obtained after derivatization with anisaldehyde-sulphuric acid reagent were used as a dataset for multivariate analysis. Principal component analysis and Orthogonal Partial Least Squares Discriminant Analysis confirmed the discrimination of samples belonging to vegetative phase, flowering stage, and seed formation stage of the plant development. The obtained results showed that the HPTLC-based metabolomics approach can be a very reliable technique for the investigation of metabolic changes during plant development, complementary to GC-MS and NMR-based metabolomics. Описана је холистичка примена нетаргетне метаболомике базиране на високоефикасној танкослојној хроматографији (HPTLC) која омогућава поређење метаболичких профила Artemisia annua и праћење њихових промена током развоја биљке. HPTLC хроматограми након развијања анизалдехидом и сумпорном киселином су коришћени за генерисање података за мултиваријантну анализу. Анализа главних компоненти (PCA) и ортогонална дискриминанта анализа најмањих квадрата (OPLS-DA) су потврдиле разлике између узорака који припадају различитим фенофазама - вегетативној фази, фази цветања и фази формирања семена. Добијени резултати указују да метаболомички приступ заснован на HPTLC методи која је комплементарна са GC-MS и NMR анализом, може бити веома поуздана техника за анализу промене током развоја биљке.

Oregano is one of the most used culinary herb and it is often adult­erated with cheaper plants. In this study, GC–MS was used for identification and quan­tification of metabolites from 104 samples of oregano (Origanum vul­gare and O. onites) adulterated with olive (Olea europaea), venetian sumac (Cotinus coggy­gria) and myrtle (Myrtus communis) leaves, at five different concentration levels. The metabolomics profiles obtained after the two-step derivatization, involving methoxyamination and silanization, were subjected to multivariate data analysis to reveal markers of adulteration and to build the reg­ression models on the basis of the oregano-to-adulterants mixing ratio. Ortho­gonal partial least squares enabled detection of oregano adulterations with olive, Venetian sumac and myrtle leaves. Sorbitol levels distinguished oregano samples adulterated with olive leaves, while shikimic and quinic acids were recognized as discrimination factor for adulteration of oregano with venetian sumac. Fructose and quinic acid levels correlated with oregano adulteration with myrtle. Orthogonal partial least squares discriminant analysis enabled dis­crimination of O. vulgare and O. onites samples, where catechollactate was found to be discriminating metabolite. Оригано је једна од најчешће коришћених кулинарских биљака и често се криво- твори јефтинијим биљкама. У овој студији, гаснa хроматографијa–масенa спектро- метријa коришћена је за идентификацију и квантификацију метаболита из 104 узорка оригана (Origanum vulgare и O. onites) кривотвореног маслином (Olea europea), венеци- јанским сумаком (Cotinus coggygria) и миртом (Myrtus communis), у пет различитих концентрација. Метаболомички профили добијени након двостепене дериватизације, која укључује метоксиаминовање и силанизацију, подвргнути су мултиваријантној ана- лизи података како би се открили маркери кривотворења и направили регресиони модели на основу односа мешања оригана и биљака за кривотворење. Ортогонална дели- мична анализа најмањих квадрата је омогућила детекцију кривотворења оригана лишћем маслине, венецијанског сумака и мирте. Садржај сорбитола разликовао је узорке оригана кривотворених лишћем маслине, док су шикиминска и кининска кисе- лина препознате као фактор разликовања за кривотворење оригана венецијанским сумаком. Садржај фруктозе и кининске киселине у корелацији су са кривотворењем оригана миртом. Ортогонална делимична анализа најмањих квадрата – дискриминантна анализа је омогућила разликовање узорака O. vulgare и O. onites, при чему је одређено да је катехоллактат метаболит који разликује ове две биљне врсте. Part of the theme issue honoring Professor Emeritus Slobodan Milosavljevićs 80th birthday.

Hexane extracts of Heracleum verticillatum, H. sibiricum, H. angustisectum, and H. ternatum were studied for their furanocoumarin content antioxidant potential and acetylcholinesterase and α-amylase inhibitory activities. Quantification of the furanocoumarins was performed by 1 H-NMR. Pimpinellin was found to be the main component in the roots of all studied species. Bergapten and imperatorin were the major compounds in the fruits of H. sibiricum and H. verticillatum, respectively, while byakangelicol dominated in H. angustisectum and H. ternatum fruits. The leaf and fruit extracts of H. angustisectum demonstrated the highest DPPH radical scavenging activity and TEAC (IC50 0.58 mg/mL and 1.83 mm, respectively). The root extracts of H. verticillatum and H. angustisectum were found to be the most effective against acetylcholinesterase (IC50 0.30 and 0.34 mg/mL, respectively). The studied extracts were not active or demonstrated a weak inhibitory effect (%Inh. up to 29.7) towards α-amylase.

Hexane extracts of Heracleum verticillatum, H. sibiricum, H. angustisectum, and H. ternatum were studied for their furanocoumarin content antioxidant potential and acetylcholinesterase and α-amylase inhibitory activities. Quantification of the furanocoumarins was performed by

Segmented thermoplastic polyurethane copolymers (PURs) were synthesized using 4,4'-methylenediphenyl diisocyanate and 1,4-butanediol as the hard segment and α,ω-dihydroxy-poly(propylene oxide)-b-poly(dimethylsiloxane)-b-poly(propylene oxide) (PPO-PDMS) as the soft segment. The content of incorporated soft segments in PURs varied in the range from 40 to 90 wt.%. The structure, molecular weights and crystallinity of obtained copolymers were monitored by FTIR, 1H, 2D NMR spectroscopy, GPC and DSC analysis, respectively. Surface free energy analysis indicates the presence of hydrophobic (siloxane) groups on the surface, giving highly hydrophobic nature to the obtained PURs films. Water absorption measurements showed that the increase of the hydrophobic PPO-PDMS segment content, led to the decrease of percentage of absorbed water in copolymers. SEM and AFM analysis revealed that copolymers with lower content of PPO-PDMS segments have higher microphase separation between segments. The results obtained in this work indicate that synthesized PURs based on PPO-PDMS, demonstrated proper surface and morphological properties with a great potential for variety of applications such as hydrophobic coatings in biomedicine. [Projekat Ministarstva nauke Republike Srbije, br. 172062]

Phytochemical analyses of the cultivated Sideritis raeseri subsp. raeseri in four different stages of flower development were performed. Traditionally used infusion and decoction were also prepared from aerial parts in full flowering stage, and analyses of active compounds and radical scavenging capacity were performed. The highest yield of the essential oil, obtained by hydrodistillation, was noticed in the full flowering phase (0.11%), with sesquiterpene bicyclogermacrene as the main constituent (42.5%). All examined extracts contained phenolic compounds and their amounts varied from 15.3 to 34.1 mg GAE/g DW. The amounts of total phenolics in infusion and decoction were similar (46.5 and 43.9 mg GAE/100 ml, respectively). LC–ESI-MS analyses of all samples allowed the characterisation of 22 phenolic compounds. Two dominant flavone glycosides, 4′- O -methylhypolaetin-7- O -[6‴- O -acetyl-β- d -allopyranosyl (1 → 2)-β- d -glucopyranoside ( 17 ) and 4′- O -methylisoscutellarein-7- O -[6‴- O -acetyl-β- d -allopyranosyl-(1 → 2)]-β- d -glucopyranoside ( 19 ) were quantified using HPLC. Moreover, the mineral content and the percent of transportation were investigated.

Seed extracts from eight grape cultivars (Vitis vinifera) growing in Serbia were screened for their polyphenolic composition by means of HPLC/PDA/ESI/MS analysis. The study revealed 34 phenolic compounds belonging to the following groups: flavan-3-ol monomers, proanthocyanidins, flavonols, hydroxycinnamic acids and hydroxybenzoic acid derivatives. The quantities of the main constituents were determined using PDA/HPLC. Qualitative and quantitative differences among the cultivars were observed.

A comparative analysis of the phenolic compounds in the 70% EtOH extracts of Hypericum acutum, H. androsaemum, H. barbatum, H. hirsutum, H. maculatum, and H. richeri has been carried out using high-performance liquid chromatography coupled with photodiode array UV detection and high resolution TOF mass spectrometry. Quercetin, astilbin, I3, II8-biapigenin, orientin, 2”- O-acetylorientin, three phenolcarboxylic acids, and eight flavonols 3- O-glycosides were identified in the extracts on the basis of their on-line UV spectra, accurate mass spectral data, and in comparison of retention times with those from the standards. Fingerprint analysis of the extracts revealed significant differences in the qualitative and quantitative chemical composition of the studied species. Antioxidant assays with various reaction mechanisms were used including ferric reducing antioxidant power (FRAP) assay, DPPH, ABTS, superoxide anion radical scavenging capacity and inhibition of liposome peroxidation induced by Fe2+. The most potent were extracts of H. acutum and H. maculatum indicating this Hypericum species interesting for further research aimed as a potentially new source of biologically active compounds.

Within this paper a new idea for the removal of organically bonded sulphur from fossil fuels is discussed. Dibenzothiophene (DBT) was used as a model compound of organicmolecules containing sulphur. This form of (bio)desulphurization was performed by an indirect mechanism in which iron(III) ions generated from pyrite by Acidithiobacillus ferrooxidans performed the abiotic oxidation. The obtained reaction products, dibenzothiopene sulfoxide and dibenzothiophene sulfone, are more soluble in water than the basic substrate and the obtained results confirmed the basic hypothesis and give the possibility of continuing the experiments related to application of this (bio)desulphurization process. .

This paper presents new data for secondary metabolites and biological activity of the insufficiently studied European inland halophytes as remarkable indicators of Balkan saline habitats. Phenolic content, flavonoid concentrations and antioxidant activity were analyzed in fifteen terrestrial salt tolerant plants collected from eight saline habitats situated in two distinct semiarid regions of Serbia. Total phenols ranged from 31.86 to 212.71 mg of GA/g of extract (gallic acid equivalent – milligrams of gallic acid per gram of extract). Concentration of flavonoids ranged from 41.21 to 146.06 mg of RU/g of extract (rutin equivalent – milligrams of rutin per gram of extract). Antioxidant activity was determined using 1,1-diphenyl-2-picrylhydrazyl radical reagent; obtained values was ranged from 1785.81 to 17.55 μg/ml. A significant relation was noticed between the concentration of phenols and antioxidant activity. Parallel to the analysis of researched halophytes, Camellia sinensis and Ginkgo biloba were analyzed for comparison. The best antioxidant properties were determined for Statice gmelinii, Artemisia santonicum and Mentha pulegium. The results indicate a potential of studied halophytic species as candidates for natural sources of secondary metabolites with high biological activity, whereas their bioactive compounds might have a significant role in adaptations to salt and drought stress.

Phenolic compounds are very important quality parameters of wine because of their impact on colour, taste and health properties. The present study aimed to evaluate the general phenolic composition and free radical scavenging activity of aqueous and organic fractions obtained using liquid/liquid extractions from red wine produced from Serbian autochtonous grape variety Prokupac. Total phenolic contents in different fractions ranged from 48.22 to 289.12 mg GAE/g dry fraction. Phenolic acids (mainly hydroxycinnamic acids) and quercetin-3-glucuronide were the main components of the EtOAc fraction at pH 2.0; catechins, phenolic acids (mainly hydroxybenzoic acids) and quercetin were found in the EtOAc fraction at pH 7.0, while anthocyanins were identified in the aqueous residue after EtOAc extraction. The major anthocyanin extracted into aqueous fraction was malvidin-3-glucoside, while the most abundant non-anthocyanin phenolic compounds from organic fractions were ethyl gallate and trans-caftaric acid. Radical scavenging activity differed significantly among fractions and IC50 values were 138.58 μg/ml for water fraction, 17.83 and 3.47 μg/ml for EtOAc fractions at pH 2.0 and pH 7.0, respectively. As the EtOAc fractions were found to be more potent radical scavengers, it could be assumed that non-anthocyanin phenolic compounds were responsible for such activity in Prokupac wine. [Projekat Ministarstva nauke Republike Srbije, br. 46013]

In this study, the synthesis, structure and physical properties of two series of thermoplastic polyurethanes based on hydroxypropyl-terminated poly(dimethylsiloxane) (HP-PDMS) or hydroxyethoxypropyl-terminated poly(dimethylsiloxane) (EO-PDMS) as soft segments, and 4,4'-methylenediphenyl diisocyanate and 1,4-butanediol as hard segments were investigated. The polyurethanes were synthesized by two-step polyaddition in solution. The effects of the type and content of PDMS segments on the structure, thermal and surface properties of copolymers were studied by H-1-, C-13-nuclear magnetic resonance (NMR) spectroscopy and two-dimensional NMR spectroscopies (heteronuclear multiple bond correlation (HMBC) and rotating-frame nuclear Overhauser effect (ROESY)), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide-angle X-ray scattering (WAXS), scanning electron microscopy (SEM) and water contact angle and water absorption measurements. Thermal properties investigated by DSC indicated that the presence of soft PDMS segments lowers the glass transition and melting temperatures of the hard phase as well as the degree of crystallinity. SEM analysis of the copolymers with a lower soft segment content confirmed the presence of spherulite superstructures, which arise from the crystallization of the hard segments. When compared with polyurethanes prepared from HP-PDMS, the copolymers synthesized from EO-PDMS with the same content of the soft segments had a higher degree of crystallinity, better thermal stability and a less hydrophobic surface. The obtained results showed that the synthesized polyurethanes had good thermal and surface properties, which could be further modified by changing the type or content of the soft segments.

Segmented poly(urethane-urea-siloxane)s (PUUS) were synthesized using 4,4'-methylenediphenyl diisocyanate (MDI) and ethylene diamine (ED) as the hard segment components and hydroxypropyl-terminated poly(dimethylsiloxane) (PDMS) as the soft segment component, where the hard segment content ranged from 38 to 65 wt%. Segmented PUUSs were prepared by a two-step polymerization procedure in tetrahydrofuran/N-methylpyrrolidone (THF/NMP) mixture with a large proportion of polar solvent. The structure, composition and hard segment length were determined by C-13 NMR and two-dimensional correlation spectroscopy. Thermal, mechanical, small-angle X-ray scattering and hydrogen bonding analyses indicated the formation of the microphase-separated copolymers with high tensile strength. Globular superstructures observed in the copolymer films by scanning electron microscopy (SEM) and atomic force microscopy (AFM) were probably arisen from the microstructural organization of the MDI-ED segments, depending on their content and length. The PUUS copolymers showed high water resistance and became more hydrophobic with increasing weight fraction of PDMS.

An investigation of the chemical composition and antimicrobial activity of the essential oil of Galatella linosyris is presented. The chemical analysis (GC/MS, NMR) showed that sabinene (40 %), beta-pinene (35.5 %), alpha-pinene (4.5 %), limonene (4 %), gamma-muurolene (4 %), and (E)-caryophyllene (3.3 %) were dominant components in this oil. Microdilution assays were used to evaluate the minimum inhibitory concentration (MIC) and the minimum bactericidal/fungicidal concentrations (MBC/MFC). G. linosyris essential oil exhibited better antibacterial activity against some of the tested bacteria than antifungal activity. U ovom radu je prikazano ispitivanje hemijskog sastava i antimikrobne aktivnosti etarskog ulja biljne vrste Galatella linosyris. Hemijskom analizom (GC-MS i NMR) je utvrđeno da su glavni sastojci ovog etarskog ulja sabinen (40 %), β-pinen (35,5 %) , α-pinen (4,5 %), limonen (4 %), γ-muurolen (4 %) i (E)-kariofilen (3,3 %). Za procenu minimalne inhibitorne koncentracije (MIC) i minimalne baktericidne/fungicidne koncentracije (MBC/ /MFC) korišćeni su testovi mikrorazblaženja. Etarsko ulje G. linosyris je pokazalo bolju antibakterijsku nego antifungalnu aktivnost.

From the seeds of white currant (Ribes rubrum, cv. White Champagne), a new sesquiterpenoid glycoside 1 was isolated, along with two known compounds: dihydrophaseic acid 3'-O-beta-D-glucopyranoside (2), and 3-carboxymethyl-indole-1-N-beta-D-glucopyranoside (3). The structure of the new compound was identified as dihydrophaseic acid 3'-O-beta-gentiobioside, based on extensive NMR and MS spectral studies. Iz semena bele ribizle (Ribes rubrum, cv. bela šampanjska) izolovan je novi seskviterpenski glukozid (1), zajedno sa dva poznata jedinjenja: 3'-O-b-D-glukopiranozidom dihidrofazeinske kiseline (2) i 3-karboksimetilindol-1-N-b-D-glukopiranozidom (3). Na osnovu detaljnih NMR i MS studija, struktura novog jedinjenja je određena kao 3'-O-b-genciobiozid dihidrofazeinske kiseline.

The cytoprotective activity of F16BP has been documented in severe conditions such as convulsions, reperfusion injury, septic shock, diabetic complications, hypothermia-induced injury, UV-provoked skin damage and in other processes including apoptosis and excitotoxicity. F16BP shows very efficient cytoprotective activity in astroglial cells exposed to H(2)O(2)-provoked oxidative stress and during neuronal injury caused by hypoxic conditions. As most of the aforementioned processes involve iron activity-related conditions, we investigated the ferric and ferrous iron binding properties of F16BP under physiological conditions using (31)P NMR and EPR spectroscopy. Our results indicate that cytoprotective F16BP activity is predominantly based on ferrous iron sequestration. (31)P NMR spectroscopy of F16BP employing paramagnetic properties of iron clearly showed that F16BP forms stabile complexes with Fe(2+) which was verified by EPR of another divalent cation-Mn(2+). On the other hand, F16BP does not sequester ferric iron nor does it increase its redox activity as shown by (31)P NMR and EPR spin-trapping. Therefore, F16BP may be beneficial in neurodegenerative and other conditions that are characterised by ferric iron stores and deposits.