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A new flavonoid glucoside derivative, patuletin 3-O-(2-O-feruloyl)-beta-D-glucuronopyranosyl-(1 -> 2)-beta-D-glucopyranoside, named atriplexin IV (1), and three new triterpenoid saponin derivatives, two sulfonylated, beta-D-glucopyranosyl-3-O-(2-O-sulfo-beta-D-galactopyranosyl)-(1 -> 2)-alpha-L-arabinopyranoside-30-alolean-12-en-28-oate (2), named atriplexogenin I, beta-D-glucopyranosyl-3-O-(2-O-sulfo-beta-D-galactopyranosyl)-(1 -> 2)-alpha-L-arabinopyranoside)-30-hydroxyolean-12-en-28-oate (3), named atriplexogenin II, and beta-D-glucopyranosyl-3-D-(beta-D-glucopyranosyl-(1 -> 2)-beta-D-galactopyranosyl-(1 -> 2)-alpha-L-arabinopyranoside)-30-alolean-12-en-28-oate (4), named atriplexogenin III, were isolated by silica gel column and semipreparative HPLC chromatography from the n-butanol extract of the salt marsh plant Atriplex tatarica. In addition, two known secondary metabolites, patuletin3-O-beta-D-apiofuranosyl-(1 '''-> 2 '')-beta-D-glucopyranoside (5) and patuletin 3-O-5 '''-O-feruloyl-beta-D-apiofuranosyl-(1 '''-> 2 '')-beta-D-glucopyranoside (6), were isolated for the first time from A. tatarica. The structures of the isolated compounds were elucidated by 1D and 2D NMR, HRESIMS, IR, and UV data. Antibacterial activity by the microdilution method and antibiofilm activity against P. aeruginosa were assessed. Compound 5 possesses significant antibacterial activity, while the most potent antibiofilm agent is compound 2.

This study was performed to determine the main antibacterial compounds of the essential oil (EO) of saltmarsh plant Artemisia santonicum (Asteraceae). The combination of HPTLC and direct bioautography was used for the activity guided isolation of isogeranic acid as the main antibacterial constituent with remarkable antimicrobial activity, although it was the minor component of the EO, present only in 0.2 %, as calculated from GC/FID. Its structure was determined by 1D- and 2D-NMR and GC-MS techniques. Antibacterial activity of isogeranic acid against all tested bacteria was significantly higher than EO and even than both controls streptomycin and ampicillin. In further investigation of antibiofilm and antiquorum sensing activity EO exhibited the best inhibition of the biofilm formation at 1/8 minimal inhibitory concentration (MIC) and isogeranic acid at 1/2 MIC. Both EO and isogeranic acid possessed pyocyanin inhibitory activity showing the reduction of pigment at 60.6 and 62.8 %, respectively, at 1/2 MIC concentrations.

Grape pomace (grape skin, seeds, and stems) represents a valuable source of bioactive compounds, thus the interest in making use of these wine waste products is increasing. Prokupac is an autochthonous Serbian variety of black grape with a long tradition in production of red wine. Identification of the superficial polyphenolic compounds by LC/MS revealed presence of 19 compounds including hydroxybenzoic acid derivatives, ellagic acid derivatives, flavan-3-ol monomers, proanthocyanidins, and flavonols. Catechin and epicatechin together with proanthocyanidins were the most abundant compounds and the highest content of phenolic compounds was determined in Prokupac clones 43/1, 40/1, and 40/2. Grape seed oil consisted of dominantly UFA (87-95 %) where methyl linoleate was the most abundant in all samples (69-81 %). Palmitic (3-8 %) and stearic acid (2-4 %) methyl esters were dominant SFA. Prokupac clone 43/3 was the most abundant in UFA (95 %) with the lowest percentage of SFA (5 %), while clones 41/1 and 43/5 had the lowest percentage of UFA (87 %) and the highest content of SFA (13 %). Favorable chemical profile of Prokupac clone seeds implicates its potential to be used as a raw material in further processing and possibility to be included as one of the quality parameters in further selection of the most interesting Prokupac clone.

From the aerial parts of Atriplex littoralis, three new flavonoid glycosides named atriplexins I-III (1-3), a known flavonoid glycoside, spinacetin 3-O-beta-D-glucopyranoside (4), arbutin (5), and 4-hydroxybenzyl-beta-D-glucopyranoside (6) were isolated. Their structures were elucidated on the basis of detailed spectroscopic analysis, including ID and 2D NMR (COSY, NOESY, TOCSY, HSQC, HMBC) and HRESITOF MS data. The compounds were tested for in vitro protective effects on chromosome aberrations in peripheral human lymphocytes using a cytochalasin-B-blocked micronucleus (MN) assay in a concentration range of 0.8-7.4 mu M of final culture solution. Chromosomal damage was induced by 2 Gy of gamma-radiation on binudeated human lymphocytes, and the effects of the compounds were tested 2 to 19 h after irradiation. The frequency of micronuclei (MNi) was scored in binudeated cells, and the nuclear proliferation index was calculated. The highest prevention of in vitro biochemical and cytogenetic damage of human lymphocytes induced by gamma-radiation was exhibited by 3 (reduction of MN frequency by 31%), followed by 4 and 6.

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-b-D-glucopyranoside (2), and 3-carboxymethyl-indole-1-N-b-D-glucopyranoside (3). The structure of the new compound was identified as dihydrophaseic acid 3'-O-b-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.

Wine quality depends mainly on the characteristics of the grape it is made of, and one of the attributes affecting wine composition is cluster and berry morphology. The aim of this study was to represent variability of the morphological characteristics between different clones of the autochthonous grape variety Prokupac and to perform chemical evaluation of wines obtained from them. Total phenolic content was generally low and it ranged from 33.0 to 114.5 mg GAE/100 mL. Six main anthocyanin compounds including malvidin as the main anthocyanidin were detected. Malvidin 3-O-glucoside was the most abundant anthocyanin with concentration of 59.8 to 101.7 mu g/mL. Clones 43/5 and 43/4 yielded highest quality wines. According to the results, clonal selection makes a significant difference in Prokupac wine quality. On the other hand, there is a minor dependance of wine quality parameters to variation in morphological attributes of clusters and berries (bunch weight, proportion of stem, berry and seed weight, skin, pulp and seed weight per berry).

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.

Some primary and secondary metabolites, as well as mineral nutrients in pulp, peel and juice obtained from four Serbian indigenous apple cultivars (Kozara, Kolacara, Budimka and.Sumatovka) collected at two different developmental stages were studied. With advanced maturation soluble solids content, total and reducing sugars increased, while L-ascorbic acid content and titratable acidity decreased. Thirteen phenolic compounds were quantified using LC-MS/MS. The total phenolic content (TPC) ranged from 9.37 to 1440 mg/100 g fw, and 0.83 to 7.84 mg/100 g fw in peel and pulp samples, respectively. Quercetin derivatives were the major detected polyphenolic group. Majority of determined phenolic compounds were influenced by cultivar and the best sources were cultivars Kolgara and Budimka. The content of flavonols (with the exception of quercitrin) varied significantly depending on maturity at harvest. With regard to mineral analysis, K was the most abundant ranging from 104 to 158 mg/100 g fw in peel, 74.4 to 93.3 mg/100 g fw in pulp, and 77.1 to 91.5 mg/100 g fw in juice samples. Obtained results provide detailed information on nutritional potential and chemical composition of tested apple cultivars and thereby could encourage their wider cultivation and consumption

Novel polyurethane copolymers derived from 4,4'-methylenediphenyl diisocyanate (MDI), 1,4-butanediol (BD) and alpha, omega-dihydroxy-[poly(caprolactone)-poly (dimethylsiloxane)-poly(caprolactone)] (a, x-dihydroxy( PCL-PDMS-PCL); (M) over bar (n) 6100 g mol(-1)) were synthesized by a two-step polyaddition reaction in solution. In the synthesis of the polyurethanes, the PCL blocks served as a compatibilizer between the nonpolar PDMS blocks and the polar comonomers, MDI and BD. The synthesis of thermoplastic polyurethanes (TPU) with high soft segment contents was optimized in terms of the concentrations of the reactants, the molar ratio of the NCO/OH groups, and the time and temperature of the polyaddition reaction. The structure, composition, and hard MDI/BD segment length of the synthesized polyurethane copolymers were determined by H-1, C-13-NMR, and two-dimensional correlation (COSY, HSQC, and HMBC) spectroscopy, while the hydrogen bonding interactions in the copolymers were analyzed by FT-IR spectroscopy. The influence of the reaction conditions on the structure, molecular weight, thermal, and some physical properties was studied at constant composition of the reaction mixture. A change in the molar ratio of the NCO/OH groups and the reaction conditions modified not only the molecular weight of the synthesized polyurethanes, but also the microstructure and therefore the thermal and physical properties of the copolymers. It was demonstrated that only PCL segments with high soft segment contents crystallize, thereby showing spherulitic morphology.

Condensation derivatives of ethyl hydrazinoacetate with 2-formylpyridine and quinoline-2-carboxaldehyde were synthesized. Pd(II), Pt(II) and Cd(II) complexes with the 2-formylpyridine derivative and a Cd(II) complex with the quinoline-2-carboxaldehyde derivative were synthesized and characterized by spectroscopic techniques. In the complexes, both ligands are coordinated in neutral NN bidentate modes, while the remaining two coordination sites are occupied by chloride. All compounds showed biological activity when tested against Escherichia coli, Bacillus subtilis and Staphylococcus aureus.

New complexes of Pt(II) and Pd(II) with 2-quinolinecarboxaldehyde selenosemicarbazone were synthesized and characterized by elemental analysis, NMR and IR spectroscopy and molar conductivity measurements. The assumed geometry of Pt(II) and Pd(II) complexes was square planar where the ligand was tridentately coordinated via the quinoline and imine nitrogen atoms and the selenium atom. The cytotoxic activity of the new Pt(II) and Pd(II) compounds, as well as of some previously synthesized Cd(II), Zn(II) and Ni(II) complexes with the same or analogous ligand, was tested against a panel of three human cancer cell lines: human cervix carcinoma cells (HeLa), human melanoma cells (FemX) and breast cancer cells (MDA-361). All investigated compounds, except Pt(II) complex, possess a strong dose-dependent cytotoxic activity of the same order of magnitude as cisplatin (CDDP). The investigation of potential of these compounds to induce HeLa cell cycle perturbations was also evaluated.

Two flavonoid glycosides 1 and 2 having the luteolin structure were isolated from flowers of the endemic plant species Cephalaria pastricensis. They were identified by (1)H and (13)C NMR, as well as UV/Vis spectroscopy. The structures of 1 and 2 were also confirmed by the spectral data of aglycones and TLC of the sugars obtained after acid hydrolysis. Flavones 1 and 2 showed significant antiradical activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay., Iz cvetova Cephalaria pastricensis izolovana su dva heterozidna flavonoida sa luteolinskim aglikonom (1 i 2). Wihova struktura je određena primenom 1H i 13C-NMR i UV spektroskopije. Strukture flavona 1 i 2 su potvrđene i spektrima aglikona, odnosno tankoslojnom hromatografijom oslobođenih šećera nakon kisele hidrolize. Jedinjenja 1 i 2 su pokazala značajnu antiradikalsku aktivnost u 1,1-difenil-2 pikrilhidrazil (DPPH) testu.