Antioxidant Capacities and Phenolic Levels of Different Varieties of Serbian White Wines

The biologically active compounds in wine, especially phenolics, are responsible for reduced risk of developing chronic diseases (cardiovascular disrease, cancer, diabetes, etc.), due to their antioxidant activities. We determined the contents of total phenolics (TP) and total flavonoids (TF) in selected Serbian white wines by colorimetric methods. Total antioxidant activity (TAA) of the white wines was analyzed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay. Međaš beli had the highest content of TP, TF and TAA. The radical scavenging capacity (RSC) and total antioxidant activity (TAA) of white wines were 15.30% and 1.055 mM Trolox equivalent, respectively. Total phenolic (TP) and total flavonoid (TF) contents in white wines ranged from 238.3 to 420.6 mg gallic acid equivalent per L of wines and 42.64 to 81.32 mg catechin equivalent per L of wines, respectively. A high and significant correlation between antioxidant activity and total phenolic content was determined in wines (R2 = 0.968, p < 0.01). For the individual polyphenols determination we used a high performance liquid chromatography (HPLC)-diode array detection (DAD) technique. The majority of white wine polyphenols was represent by four hydroxycinnamic acids (HCAs)

Determination of residues of sulfonylurea herbicides in soil by using microwave-assisted extraction and high performance liquid chromatographic method

A modified method for the analysis of nicosulfuron, rimsulfuron and prosulfuron was developed and validated by using microwave-assisted extraction (MAE) and ultra-performance liquid chromatography with diode array detection in the ultraviolet region (HPLC-UV-DAD). The most important experimental parameters of extraction procedure and HPLC-UV-DAD technique were optimised in respect to those sulfonylurea herbicides. High recoveries of the microwave-assisted extraction were obtained by using a dichloromethane-acetonitrile mixture (2:1 volume ratio) acidified with acetic acid (0.8 vol.%) with the addition of urea. The mean recoveries at three spiking levels ranged from 97.47 to 98.76% for nicosulfuron, 97.88 to 99.17% for rimsulfuron and from 97.91 to 99.83% for prosulfuron. The limits of detection of nicosulfuron, rimsulfuron and prosulfuron were 0.95, 0.91 and 0.89 mu g kg(-1), respectively. The accuracy of the developed method was confirmed by HPLC coupled with tandem mass spectrometry parallel analyses. The developed method was used to investigate the dissipation dynamics of sulfonylurea herbicides in the real field trials in Vojvodina Province, Serbia. The obtained half-lives were 0.05, 0.23 and 0.15 days for recommended dose application of nicosulfuron, rimsulfuron and prosulfuron, respectively. Low residues and short half-life in soil suggested that the risk to sensitive rotational crops after application of those sulfonylurea herbicides is low when they are used in the appropriate dosages

Primena tečne hromatografije sa DAD detektorom za određivanje ostataka acetamiprida i 6-hlornikotinske kiseline u uzorcima trešanja

A rapid and simple method for simultaneous determination of acetamiprid and its metabolite 6-chloronicotinic acid in sweet cherry samples has been developed. This residue analysis method is based on the reversed phase separation on C18 column with gradient elution. Analytes' determination and quantification were performed by high performance liquid chromatography (HPLC) with diode-array detector and chromatograms were extracted at 230 nm. Extraction efficiency experiments demonstrated the ability of this method to extract neonicotinoids from sweet cherry samples. These insecticides were extracted with a mixture of acetonitril/0.1N ammonium-chloride (8/2, v/v). The average recoveries of acetamiprid and 6-chlornicotinic acid from sweet cherry samples were in the range of 95-101% and 73-83%, respectively, with the associated relative standard deviations (RSDs) lt 5%. Expanded measurement uncertainties for the analyzed compounds were 2.7 and 3.01%. The limit of quantification (LOQ) was 10 μg/kg and 30 μg/kg for acetamiprid and 6-chloronicotinic acid, respectively. Thus, the developed HPLC/DAD method can be considered a useful tool for sensitive and rapid determination of acetamiprid and 6-chloronicotinic acid. Hence, the method may find further application in the analysis of real sweet cherry samples contaminated with these insecticides at a ppb level.U radu je predstavljena jednostavna metoda za određivanje acetamiprida i njegovog metabolita, 6-hlornikotinske kiseline, u uzorcima trešanja. Metoda je bazirana na primeni reverzno-faznog razdvajanja na C18 koloni primenom gradijentnog eluiranja. Određivanje i kvantifikacija analita je vršena tečnom hromatografijom (HPLC) sa DAD detektorom, pri čemu je korišćena talasna dužina od 230 nm. Tačnost metode je ocenjena procenom merne nesigurnosti. Ekstrakcija acetamiprida i 6-hlornikotinske kiseline iz uzoraka trešanja je vršena smešom acetonitril/amonijum-hlorid (0,1N) u odnosu 80:20 (v/v). Sva merenja su vršena u tri ponavljanja, pri čemu su dobijeni prinosi određivanja acetamiprida i 6-hlornikotinske kiseline u rasponima 95-101% i 73-83%, respektivno. Relativne standardne devijacije (RSD) merenja su u svim slučajevima bile ispod 5%. Limiti kvantifikacije za acetamiprid i 6-HNK iznosili su 10 i 30 μg/kg, respektivno. Kombinovana merna nesigurnost rezultata analize acetamiprida i njegovog metabolita procenjena je na 1,35, odnosno 1,50%, a proširena na 2,7 i 3,01%, upotrebom faktora pokrivanja (k=2) koji odgovara nivou poverenja od 95%, za normalnu raspodelu. Nakon validacije i procene merne neizvesnosti dobijeni rezultati pokazuju da se razvijena HPLC/DAD metoda može primeniti za određivanje sadržaja acetamiprida i 6-hlornikotinske kiseline u uzorcima trešanja i relevantnim matriksima kontaminiranim ovim jedinjenjima

Razgradnja acetamiprida u plodovima trešanja

Degradation of acetamiprid in sweet cherry samples was evaluated at several intervals from the product application until the end of the pre-harvest interval. An orchard of sweet cherries located at Stepanovićevo village near Novi Sad was used in this study. Acetamiprid was applied according to the manufacturer's recommendation for protecting sweet cherries from their most important pests. Sweet cherry fruit samples were collected at eight intervals: immediately after acetamiprid application and 2, 4, 6, 8, 10, 12 and 14 days after application. The extraction of acetamiprid from sweet cherry samples was performed using a QuEChERS-based method. Determination was carried out using an HPLC-UV diode array detection system (Agilent 1100, United States) with an Agilent Zorbax Eclipse C18 column (50 mm × 4.6 mm internal diameter, 1.8 μm particle size). The method was subjected to a thorough validation procedure. The recovery data were obtained by spiking blank sweet cherry samples at three concentration levels (0.1-0.3 mg/ kg), yielding 85.4% average recovery. Precision values expressed as relative standard deviation (RSD) were below 1.61% for the intraday precision. Acetamiprid showed linear calibrations from 0.05 to 2.5 μg/ml with correlation coefficient (R2) of 0.995%. The limit of detection and limit of quantification were found to be 5 μg/kg and 14 μg/kg, respectively. The validated method was applied in the analysis of acetamiprid in sweet cherry samples. During the study period, the concentration of acetamiprid decreased from 0.529 mg/kg to 0.111 mg/kg. The content of acetamiprid in sweet cherry samples at the end of the pre-harvest interval was below the maximum permissible level specified by the Serbian and EU MRLs.U cilju praćenja razgradnje acetamiprida u plodovima trešanja u periodu od primene preparata do isteka karence, izvršen je tretman preparatom na bazi ove aktivne materije u preporučenoj dozi. Ogled je postavljen u zasadu srednje kasne sorte trešnje na lokalitetu Stepanovićevo u okolini Novog Sada. Plodovi su uzorkovani osam puta - odmah nakon primene preparata, 2, 4, 6, 8, 10, 12 i 14 dana. Ekstrakcija acetamiprida iz trešanja izvedena je QuEChERS metodom. Za određivanje acetamiprida korišćena je tečna hromatografija sa DAD detektorom (Agilent 1100, United States) i Agilent Zorbax Eclipse C18 kolonom (unutrašnji prečnik 50 mm x 4.6 mm, veličina čestica 1.8 μm). Kao mobilna faza upotrebljeni su acetonitril i 1.5% rastvor CH3COOH (30/70), sa protokom 1 ml/min, temperaturom kolone 25 oC i injektovanom zapreminom 2,5 μl, dok je kao odgovarajuća talasna dužina usvojena vrednost od 254 nm. Validacija metode je u potpunosti sprovedena u skladu sa zahtevima standarda SANCO/12495/2011 (EU Commission Health and Consumer Protection Directorate- General, 2011). Prosečna vrednost prinosa ekstrakcije acetamiprida iz trešanja proverena na tri nivoa obogaćenja (0.1-0.3 mg/kg) iznosila je 85.4%. Preciznost merenja razmotrena proverom ponovljivosti određivanja acetamiprida izražena je relativnom standardnom devijacijom (RSD) sa vrednošću manjom od 1.61%. U opsegu masenih koncentracija acetamiprida od 0,05 do 2,5 μg/ml postignuta je dobra linearnost odziva detektora sa koeficijentom varijacije od 0,995%. Limit detekcije i kvantifikacije za određivanje acetamiprida u trešnjama prikazanom metodom iznose 5 μg/kg i 14 μg/kg. Tokom ispitivanog perioda koncentracija acetamiprida u trešnjama se smanjivala od 0,592 mg/kg neposredno nakon primene insekticida do 0,111 mg/kg po isteku karence od 14 dana. Analizom je utvrđeno da je sadržaj acetamiprida u uzorcima plodova trešnje nakon isteka perioda karence ispod maksimalno dozvoljene količine za ovu aktivnu materiju propisane Pravilnikom Republike Srbije (0,2 mg/kg) i Evropske Unije (1,5 mg/kg)

The influence of adding of flaxseed oil to sunflower oil on the content of tocopherols and carotenoids in blended edible oils

Blending vegetable oils of different composition and properties is one of the simplest methods for creating new specific products with the desired properties, which increases their commercial application and improves their nutritional quality. The effect of blending vegetable oils on tocopherols and carotenoids content was examined. Refined sunflower seed oil (S) and cold pressed flaxseed oil (F) were used in the experiment. These oils are blended in three different content of mass: sample 70S:30F (70% S and 30% F), sample 50S:50F (50% S and 50% F) and sample 30S:70F (30% S and 70% F). The results showed significant differences in the content of total tocopherols and total carotenoids between the two oils used for the preparation of three blended oils. Refined sunflower seed oil contains higher amounts of tocopherols and fewer amounts of carotenoids compared to cold pressed flaxseed oil in which the content of tocopherols is lower and the content of carotenoids is higher. In the obtained blends of edible vegetable oils, the content of total tocopherols ranged from 387.96 to 447.83 mg/kg while the determined total carotenoids content (as B-caroten) ranged from 3.11 to 5.63 mg/kg. By blending refined oil of sunflower seed and cold pressed oil of flax-seed, the balance of the parameters studied is contributed. The research in the work showed that the blending of vegetable oils provides the possibility of modulating their composition, and therefore of nutritive quality

Monitoring atrazina i njegovih metabolita u podzemnim vodama Republike Srbije

The intensive use of atrazine herbicides in the Republic of Serbia during recent decades has led to the accumulation of residues of atrazine and its metabolites in the environment, which endangers groundwater. With the objective to check the presence of atrazine and its metabolites deethylatrazine (DEA) and deisopropylatrazine (DIA) in the groundwater, the monitoring programme was carried out over the period from 2007 to 2009 in the localities where the atrazine-based herbicides were intensively applied for a number of years. Samples were taken from 327 localities, in total there were 1408 samples of groundwater of the first welling-up collected. The atrazine and its metabolites were extracted with methanol by means of ENVI-C18 (47mm) disc, and the residue level of the studied compounds was analyzed with gas chromatography-mass spectrometry (GC-MS). In the most of groundwater samples collected from agricultural regions, the average value of all tested analytes was above 0.1 µg/dm3. The highest values of atrazine and its metabolites were in the localities that are known for intensive maize production and in the areas of this region under orchards and vineyards, where atrazine was used in large quantities. The average content values of this active substance in the analyzed samples are the result of intensive and long-term usage of this group of herbicides, as well as the high level of groundwater in this region.Ekspanzija u primeni herbicida na bazi atrazina u Republici Srbiji poslednjih decenija dovela je do nagomilavanja ostataka atrazina i njegovih degradacionih produkata u životnoj sredini, čime su naročito ugrožene podzemne vode. Radi provere prisustva atrazina i njegovih metabolita deetil-atrazina (DEA) i deizopropil-atrazina (DIA) u podzemnim vodama sproveden je monitoring program u periodu 2007-2009. godine na područjima pod intenzivnom poljoprivrednom proizvodnjom na teritoriji Republike Srbije. Podzemna voda prve izdani uzorkovana je na 327 lokaliteta, ukupno je prikupljeno 1408 uzoraka. Ekstrakcija analita iz vode izvedena je metanolom uz primenu C18-ENVI diska (47 mm), dok je nivo rezidua određen primenom gasne hromatografije sa masenim spektrometrom (GC/MS). Analizom je utvrđeno prisustvo atrazina, DEA i DIA iznad 0,1 |µg/dm3 u podzemnim vodama većine lokaliteta obuhvaćenih ispitivanjem. Najveće vrednosti ispitivanih analita utvrđene su na lokalitetima sa intenzivnom proizvodnjom kukuruza, kao i na površinama pod voćnjacima i vinogradima, gde je atrazin primenjivan u velikim količinama

Akumulacija teških metala u Medicago sativa L. i Trifolium pratense L. na kontaminiranom fluvisolu

Recently, heavy metals concentrations increased in some agricultural areas due to the consequences of anthropogenic impacts. The aim of this study was to determine the level of heavy metals (As, Cr, Ni and Pb) in Medicago sativa L. and Trifolium pratense L. grown on fluvisol, in order to obtain information on safety of these nutrients. The total content of Pb, As, Cr and Ni in the samples of fluvisol was above the maximum allowable amount. The content of heavy metals in Medicago sativa L. and Trifolium pratense L. was below the critical and toxic concentrations in all samples originating from contaminated soil. It was concluded that the accumulation of heavy metals in plants did not depend only on the total content in soil, but also the affinity of the plant, and individual and interactive effects of various soil properties. No statistically significant differences in the accumulation of heavy metals between Medicago sativa L. and Trifolium pratense L were observed. It is necessary to further control of heavy metals in the investigated area, in order to prevent their entry into the food chain and provide healthy food.U poslednje vreme povećana je koncentracija teških metala na nekim poljoprivrednim površinama usled antropogenog uticaja. Cilj rada je bio da se utvrdi nivo teških metala (As, Cr, Ni i Pb) u nekarbonatnom aluvijalnom (fluvijanom) zemljištu, te njihova akumulacija u Medicago sativa L. i Trifolium pratense L., radi dobijanja informacije o zdravstvenoj ispravnostinosti ovih hraniva. Ukupan sadržaj ispitivanih teških metala u uzorcima zemljišta bio je iznad maksimalno dozvoljene količine, što znači da svi uzorci analiziranih lokaliteta pripadaju kategoriji kontaminiranog zemljišta. Sadržaj teških metala u Medicago sativa L. i Trifolium pratense L. bio je ispod kritičnih i toksičnih koncentracija, kao i maksimalno dozvoljenih količina u hrani za životinje u svim uzorcima poreklom sa kontaminiranog zemljišta. Konstatovano je da akumulacija teških metala u biljkama nije zavisila samo od ukupnog sadržaja u zemljištu, nego i afiniteta biljke, te individualnog ili interaktivnog dejstva raznih zemljišnih svojstava. Nije bilo značajnih razlika u akumulaciji teških metala izmeću Medicago sativa L. i Trifolium pratense L

Recurrent terminal ventricle cyst: a case report.

The terminal ventricle (TV) of Krause is a rare cystic dilation of the conus' central canal. Due to limited understanding surrounding its pathophysiology, optimal management remains controversial. We report a 25-year-old female presenting with acute paraparesis. Magnetic resonance imaging spine revealed a cystic conus medullaris lesion in keeping with an incidental TV cyst. However, the patient experienced a rapid resolution of symptoms. We hypothesize that the TV cyst spontaneously ruptured and auto-decompressed. To our knowledge, this is the first reported case of an enlarging symptomatic TV cyst with spontaneous rupture and resolution of symptoms, highlighting the variable natural history of this condition

Length of carotid stenosis predicts peri-procedural stroke or death and restenosis in patients randomized to endovascular treatment or endarterectomy.

BACKGROUND: The anatomy of carotid stenosis may influence the outcome of endovascular treatment or carotid endarterectomy. Whether anatomy favors one treatment over the other in terms of safety or efficacy has not been investigated in randomized trials. METHODS: In 414 patients with mostly symptomatic carotid stenosis randomized to endovascular treatment (angioplasty or stenting; n = 213) or carotid endarterectomy (n = 211) in the Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS), the degree and length of stenosis and plaque surface irregularity were assessed on baseline intraarterial angiography. Outcome measures were stroke or death occurring between randomization and 30 days after treatment, and ipsilateral stroke and restenosis ≥50% during follow-up. RESULTS: Carotid stenosis longer than 0.65 times the common carotid artery diameter was associated with increased risk of peri-procedural stroke or death after both endovascular treatment [odds ratio 2.79 (1.17-6.65), P = 0.02] and carotid endarterectomy [2.43 (1.03-5.73), P = 0.04], and with increased long-term risk of restenosis in endovascular treatment [hazard ratio 1.68 (1.12-2.53), P = 0.01]. The excess in restenosis after endovascular treatment compared with carotid endarterectomy was significantly greater in patients with long stenosis than with short stenosis at baseline (interaction P = 0.003). Results remained significant after multivariate adjustment. No associations were found for degree of stenosis and plaque surface. CONCLUSIONS: Increasing stenosis length is an independent risk factor for peri-procedural stroke or death in endovascular treatment and carotid endarterectomy, without favoring one treatment over the other. However, the excess restenosis rate after endovascular treatment compared with carotid endarterectomy increases with longer stenosis at baseline. Stenosis length merits further investigation in carotid revascularisation trials