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The procedure involving water and water-methanol extraction, RP-HPLC-C18 column chromatography with PDA detection was developed for determination of cinnamic acid and benzoic acid derivatives in grapevine’s dietary supplements (LV, RW, VIN, VIC, and DK) available on the Polish market. Phenolic acids were analysed before and after acidic and basic hydrolysis and identified against standards. Totalamount of studied phenolic acids determined by HPLC-PDA was compared with total polyphenols content (TPC) by Folin-Ciocalteu method. The average content of studied phenolic acids (70.54±0.21; 122.95±0.49; 87.67±0.10; 132.21±0.24; 266.78 ±0.39, and 18.16±0.09 mg/100 g d.m. (dry mass) for LV, RW, VIN, VIC, DK, and WW, respectively) were higher than the TPC (1489.91±0.39, 1648.19±0.14, 1574.38±0.33, 1643.64±0.12, 1984.75±0.97, and 715.55±0.36 mg/100 g d.m. for LV, RW, VIN, VIC, DK, and WW, respectively). The new developed method was validated for specifi city, repeatability, and accuracy and can be suitable for routine quality and quantity analysis of dietary supplements containing grape vine (Vitis vinifera).

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The paper presents results of the HPLC determination of sulphachloropyrazine residues (active component of the drug „Esb3 30%”) in muscle tissue and liver of broiler chickens inoculated with laboratory-grown coccidium in the course and after treatment with this sulphonamide.Extraction of sulphachloropyrazine from samples of broiler muscle tissue and liver was carried out with a mixture of solvents dichloromethane-methanol-acetic acid (90:5:5, v/v/v), followed by extract purification by chromatographic separation on a XAD-2 column and elution of sulphachloropyrazine residues with dichloromethane. The HPLC determination of sulphachloropyrazine residues was accomplished on a Bio Sil C-8 HL 5 ?m column with a mobile phase consisting of 60% aqueous solution of acetonitrile and NH3 (pH=9.5), using a UV detector at 254 nm.The method developed allows quantitative determination of the residues of the anticoccidial agent in broiler tissue samples with a detection limit of 0.02 ?g g–1. Recovery of the method for this type of samples with a complex matrix was satisfactory, the results ranging from 79.2(0.6 to 86.7(0.2% for muscle tissue and from 81.7(0.8 to 87.3(0.7% for liver.

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Previous study showed that the standardised 50% aqueous-methanol extract of Eurycoma longifolia (TAF-273) affected phase 1 aminopyrine metabolism especially in adult male and female rat hepatocytes. The present study evaluated the molecular mechanism of TAF-273 on phase 1 aminopyrine metabolism in adult male and female rat hepatocytes by using ten cellular stimulants/inhibitors. The study suggested that the effect of TAF-273 on hepatic phase 1 aminopyrine metabolism in adult male rats was probably mediated through the inhibition of tyrosine kinases and through the activation of G-protein, protein kinase G, protein kinase A in the cAMP pathway, calmodulin and protein kinase C. On the contrary, the extract affected adult female rat hepatocytes, only through the activation of G-protein, protein kinase G, protein kinase A in the cAMP pathway and protein kinase C. The effect of TAF-273 on aminopyrine metabolism in the presence of trifluoperazine, phorbol myristate acetate and genistein also exhibited significant difference (P<0.05) between male and female rats. The rate of aminopyrine metabolism was higher in male rats than in female rats and the effect of TAF-273 on aminopyrine metabolism at the molecular level was different in male and female rats on the activation of calmodulin, protein kinase C and tyrosine kinases.

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Acta Alimentaria
Authors: M. Croitoru, I. Fülöp, M. Ajtay, G. Dudutz, O. Crăciun, and M. Dogaru

To date, monosodium glutamate is the most used flavour enhancing food additive. Because high levels of glutamate are toxic to brain concerns appeared regarding the safe use of glutamate and there is a 10 g kg −1 concentration limit in foodstuff. A simple HPLC-UV method, based on a derivatization procedure with o -phthaldialdehyde, was developed for determination of glutamate in meat products, soup bases and vegetable concentrates. Even if our method is less sensitive than the HPLC-fluorescence ones widely available, it is able to measure amounts at least 200 times smaller than the maximum allowed one, has good reproducibility (CV under 2% for intraday and under 3% for interday determinations), linearity and accuracy. Less expensive HPLC systems are required and the formed derivative is very stable (at least 1 week), good separation is obtained with the less expensive 5 μm particle C 18 columns and methanol as organic phase. Concentration of free glutamate ranged between 0.14 g kg −1 in sausage without added glutamate to as high as 2.16 g kg −1 in a pork sausage. Concentration in vegetable mixes and soup bases were between 80–120 g kg −1 .

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The first objective of this study was to reveal the effect of temperature and time on the production of CLA isomers from safflower oil. For this purpose, CLA production was conducted at different temperatures (80–240 °C) and over different time durations (1–10 h). Alkali isomerisation gave a total conversion of 87.8% under the optimal conditions of 240 °C and 8 h (for maximum beneficial isomers), and produced 41.0% trans-10, cis-12, 40.4% cis-9, trans-11, and 6.4% undesirable CLA isomers. The second aim of this study was to determine the effect of temperature and solvents on the purification of CLA isomers. To achieve this, CLA solutions containing different solvents (acetone, methanol, and petroleum ether) were crystallized at several temperatures (0 to –85 °C). It was determined that although the highest CLA purities (94%) were obtained at –55 °C using acetone as the solvent with a yield of 38.1%, the highest yield (89.6%) was determined using petroleum ether at –85 °C with a purity of 88.1%. This paper presents methods to utilize safflower oil and low temperature crystallization process to inexpensively obtain beneficial CLA.

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In this laboratory research, we produced and compared different phenol extracts from olive-oil mill wastewaters. The extracts and sample preparation was as follows: 1 CW-Acetone (wastewater, previously centrifuged and treated with acetone to precipitate colloid substances); 2 CW-Ac-HCl-EtAc (this extract was recovered by ethyl acetate from the 1 CW-Acetone prior to being hydrolysed by 1N HCL at 80 °C for 1 h); 3.2 CW-20% MetOH and 4.2 CW-80% MetOH (fractions separated by solid-liquid extraction (SPE) with methanol:water mixtures at 20% and 80% (v/v), respectively).Determined in each sample were: (i) total phenols and ortho -di-phenol conducive to spectrophotometric methods; (ii) phenol composition by HPLC analysis and finally, (iii) antioxidant activity on a lard sample, using rancimat test under 120 °C temperature and 20 l h −1 air flow. The extract 1 CW-Acetone, composed essentially of local wastewater phenols, was less effective than the other extracts. Best antioxidant extract was 3.2 CW-20% MetOH that prolonged the lard’s oxidative stability 3.5 and 7.0 times at doses of 100 and 200 mg kg −1 , respectively. Antioxidant effectiveness of the various extracts were found to be directly correlating with percentage of free hydroxytyrosol. Finally, antioxidant properties of olive-oil mill wastewater extract samples was found to be the result of their phenol composition rather than their phenol content.

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Globe artichoke (Cynara scolymus L.) is a perennial plant belonging to Asteraceae family. It is one of the most suitable plants for growing organically. Artichoke has been used as choleretic, hepatoprotective, anticarcinogenic, antioxidant, antibacterial, antifungal, antimicrobial, cholesterol-reducing, and diuretic in traditional medicine. Artichoke has been cultivated worldwide because of its nutritional value and medicinal properties. In this study organically and conventionally grown artichokes were compared in terms of phenolic constituents, antibacterial and antioxidant activities. Artichoke leaves, bracts, and floral receptacles obtained from 2 different sources (organic and conventional) were freeze-dried, powdered, and extracts were prepared with methanol. Phenolic constituents (chlorogenic acid, cynarin, luteolin, and apigenin) were analysed by HPLC-DAD system. It was found that organic farming enhanced cynarin, chlorogenic acid, and luteolin amounts in receptacle (edible part). Organically grown leaves had also higher amounts of cynarin and chlorogenic acid than conventional ones. Cynarin amount was higher by 35% in organic receptacle and 20% in organic leaves. Organic farming also augmented the antioxidant property and flavonoid content of edible parts of the artichoke. Additionally, organically grown leaves had the highest antioxidant activity, total phenol and flavonoid contents. Antibacterial activity was observed with both organic and conventional leaves only against Staphylococcus epidermidis. This comparative study revealed that organic farming enhanced the health-beneficial medicinal values of artichoke's heart and leaves.

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Acta Alimentaria
Authors: I. Tas, A.B. Yildirim, E. Ozkan, G.C. Ozyigitoglu, M.Z. Yavuz, and A.U. Turker

Lichens are a symbiotic relationship between a fungus and a photosynthetic partner. Chemical characterization and bioactive potentials (antiproliferative, antioxidant, and antibacterial) of five lichen species (Evernia prunastri, Platismatia glauca, Pseudevernia furfuracea, Ramalina fastigiata, and Ramalina farinacea) were assessed. Five lichen metabolites (usnic acid, atranorin, stictic acid, evernic acid, and fumarprotocetraric acid) were analyzed by HPLC-DAD. E. prunastri was noteworthy evernic acid source. Antiproliferative activity was evaluated using human breast adenocarcinoma (MCF-7) and human hepatocellular carcinoma (HepG2/C3A) cell lines. The strongest activity was observed for P. glauca against HepG2/C3A, while the only lichen species that induced cytotoxicity against MCF-7 cell line was P. furfuracea. The highest antioxidant activity was also obtained with P. furfuracea. E. prunastri and R. farinaceae had the highest phenolic and flavonoid contents, respectively. Antibacterial activities of the extracts were determined against ten pathogenic bacteria. The most effective antibacterial agent was methanol extract of R. fastigiata. Our findings have revealed the pharmaceutical potentials of tested lichen species.

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, National Institute for Occupational Safety and Health (NIOSH). Available from: http://www.cdc.gov/niosh/npg/ Stegink, L.D., Brummel, M.C., Filer, L.J. & Baker, G.L. (1983): Blood methanol

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-homogenised tomato sample was crushed in a crucible mortar with quartz and extracted with methanol and then with 1:5 methanol:dichloroethane. The dichloroethane fraction was separated in a separating funnel after addition of 1 ml water to ensure phase separation. The

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