Investigation of content of primary and secondary oxidation products in sunflower oils with a different content of oleic acid

Oxidative stability, i.c. shelf life of oil is related to the degree of the oxidative changes in the amount of the resulting primary and secondary oxidation products of unsaturated fatty acids. In order to improve oxidative stability, i.e. oil shelf life, sunflower hybrids with altered fatty acid composition have been created, i.e. significantly higher oleic acid (C18:1) content, even over 90% w/w, relative to the linoleic type with 25-30% w/w of oleic and 60-65% w/w of linoleic acid (C18:2). In order to examine the oxidative stability of the oil, three samples of sunflower seed oil NS hybrids (NS Oliva, NS Horizont and NS Romeo) of different fatty acid composition were analyzed. Samples were exposed to moderate temperatures (6342°C) over a period of 8 days. Changes in the content of primary and secondary oxidation products based on changes in peroxide (PV) and anisidine (p-AnV) values, as well as changes in the content of conjugated dienes and trienes, were observed. The highest oxidative stability was observed in the oleic type oil sample. In this sample the determined values of the tested parameters of oxidative stability, after 8 days, were PV=4.85 mmol/kg and p-AnV=0.65, compared to the initial sample (PV=0.36 mmol/kg and p-AnV=0.57). The greatest oxidative changes occurred in the oil sample with the lowest content of oleic and the highest content of linoleic acid, as indicated by the PV=73.22 mmol/kg and p-AnV=3.60, after 8 days, in relation to PV=2.16 mmol/kg and p-AnV=0.50 in the initial linoleic type oil sample

Ispitivanje masnokiselinskog sastava u ulju semena suncokreta selekcije Instituta za ratarstvo i povrtarstvo

Stepen homogenosti suncokretovog ulja za 21 ispitivanu inbred liniju Institut za ratarstvo i povrtarsivo koje su gajene tokom 2017. godine na oglednom polju na Rimskim Sancevima, utvrden je primenom tehnike gasne hromatografije sa plameno-jonizujuéom detekeijom. Suncokretovo ulje je dobijeno postupkom hladnog presovanja suncokretovog semena. Sastav masnih kiselina u ulju utviden je postupkom transesterifikacije masnih kiselina u njihove isparljive metilestre primenom rastvora reagensa TMSH (trimetilsulfonijum-hidroksid uw metanolu) i dalje je analiziran tehnikom gasne hromatografije. Metilestri prisutnih masnih kiselina, dobijeni postupkom transesterifikacije, kvalitativno su odredeni na osnovu retencionih viemena, poredenjem sa retencionim vremenima dobijenim prethodnim analiziranjem smese metilestara masnih kiselina u analitickom standardu. Primenom hijararhijske klaster analize uspesno je dokazana slicnost med ispitiv ‘nim genotipovima, kao i njihove jasno grupisanje

Effects of well regeneration on the example of Grabovičko polje near Kladovo

Many groundwater sources face a reduction in the exploitation capacity due to well aging. The well changes its performance over time, whether in operation or out of work. The well aging is influenced by many factors. Consequently, economic, business and social problems arise. Well regeneration has shown the best effects in practice to address these issues. In the area of Kladovski Ključ on the banks of the Danube, a drainage system of wells is used to defend against high water levels. During the inspection of the wells, the products that affect the aging of the well were determined, and the regeneration of the wells was conducted using the chemical-hydraulic method. The paper presents the procedures of well regeneration and the obtained positive effects of the applied method seen through the achieved results

Investigation of the oxidation products of oil seeds of sunflower hybrids grown in Serbia and Argentina

Content of the oxidation products is very important parameter of oil quality and oxidative stability, ie. shelf life. In order to improve shelf life of oils, the breeders create new sunflower hybrids with altered fatty acid composition as well as the content of minor components that contribute to oxidative stability of oil (tocopherols, sterols, phenolic compounds, etc.)

Yield value of cold pressed oil of the latest sunflower oil hybrids

The cold pressed sunflower oil is obtained by mechanical extraction from the seed which is pressed with a different content of the hull. The content of the hull in the seed is conditioned by the type of hybrid and affects the quality and yield of cold pressed oil as well as the quality of the obtained cake. In addition to the contents of the hull, the yield of the pressing is influenced by the type of raw material. ie the content of the oil in the material for pressing, then the preparation of the material, the granulometric composition, residual impurities, etc. The structure and power of the presses, as well as the pressing conditions (pressure, temperature, duration of the process, the content of the oil in the cake, the moisture content of the raw material, etc.), also affect the effectiveness of pressing (yield). In this paper, the exploitation of the pressing (yield value) of the latest oil hybrids of the secondary filial (F2) generation grown on the territory of the Republic of Serbia was examined. The yield value in five different oil hybrids (Dusko, Orfej, NS Konstantin, NS Ronin and NS Horizont) was calculated on the basis of the oil content of seed and cake obtained after pressing. The content of the oil was determined according to SRPS EN ISO 659:2011, while the moisture content was made according to SRPS EN ISO 665:2008. The seed oil content ranged from 32.52 + 2.16 to 41.66 + 2.08 %, while the moisture content in these seeds ranged from 5.92 + 0.04 to 6.08 + 0.08 %. In the obtained cakes the content of oil was determined from 14.80 + 0.05 to 17.64 + 0.01 %, while in the same cakes the moisture content was in the range of 6.92 + 0.01 to 7.84 + 0.03 %. Of the examined samples, the maximum yield value was determined for the sample of NS Konstantin and amounted to 75.61 + 1.99 %, while the lowest yield value of 55.37 + 4.41 % was determined for the NS Horizont sample

Investigation of the oxidation products of oil seeds of sunflower hybrids grown in Serbia and Argentina.

Content of the oxidation products is very important parameter of oil quality and oxidative stability, ie. shelf life. In order to improve shelf life of oils, the breeders create new sunflower hybrids with altered fatty acid composition as well as the content of minor components that contribute to oxidative stability of oil (tocopherols, sterols, phenolic compounds, etc.). In order to examine the oxidative stability of the oil, sunflower seed oils of the same latest hybrids of the secondary filial (F2) generation grown on the territory of the Republic of Serbia and Argentina were analized. Samples were tempered at 63 + 2 °C for a period of 8 days. The content of primary and secondary oxidation products was monitored through the peroxide (PV) and anisidine values(p-AnV, as well as the content of conjugated dienes (CD) and trienes (CT). After the 4" and 8" day, the samples were taken and analysed and compared with the initial samples. Based on the content of the resulting oxidation products the best oxidative stability showed the oil seeds NS Horizont grown on the territory of Serbia. In this sample values of the tested parameters of oxidative stability in the initial sample were PVinitial = 1.99 + 0.06 mmol/kg, p-AnVinitiar = 0.08 + 0.01 and after 8 days of testing: PVéin day = 30.32 + 0.03 mmol/kg, p-AnVsth day = 2.05 + 0.01. The same sample grown in Argentina showed significantly poorer results: PVinitial = 2.00 + 0.07 mmol/kg, p-AnVinitial = 1.13 + 0.00 and PVath day = 73.45 + 4.31 mmol/kg, p-AnVath day = 3.14 + 0.01

Prediction of the firmness of the selected sunflower hybrid seed based on its technological characteristics

Sunflower seeds (Helianthus annus L.) are the most represented oilseed in Serbia. During the oil production process, the seeds are partially and/or completely dehulled. Sharma et al. (2009) found that, in addition to the moisture content of the seed, the effect of dehulling is also significantly influenced by seed firmness. The dehulling effect increases with decreasing seed firmness. This paper examines the technological characteristics of sunflower seeds of selected hybrids (true density, content of hull in seeds and mass of 1000 grains expressed on dry matter), based on which a mathematical model for prediction of seed firmness was made. The tested samples are oily hybrids, grown on the territory of Serbia in 2017, namely: NS Horizont, Sumo 2 OR, NS Sumo Sjaj, NS Samuraj CLP, NS Smaragd CLP. True density, content of hull in seed, and mass of 1000 grains expressed on dry matter were made according to Karlovi¢ and Andri¢ (1996), while seed firmness was made using Texture Analyzer TA.HD Plus (Stable Micro Systems, Godalming, U.K.). Firmness of the samples tested ranged from 5522.67 + 765.40 to 6889.10 + 1220.62 g, true density from 753.92 + 18.23 to 877.33 + 0.93 kg m°%, hull content of 47.54 + 0.13 to 55.15 + 0.87% and a mass of 1000 grains expressed on dry matter of 48.83 + 0.80 to 57.10 + 2.52 g. Model validation was also performed, and based on the statistical validation parameters, it is concluded that it is possible to predict seed firmness based on its technological characteristics

Real-life data on the efficacy and safety of ombitasvir/paritaprevir//ritonavir + dasabuvir + ribavirin in the patients with genotype 1 chronic hepatitis c virus infection in serbia

© 2019, Inst. Sci. inf., Univ. Defence in Belgrade. All rights reserved. Background/Aim. The era of direct-acting antiviral (DAA) regimen in the treatment of chronic hepatitis C virus (HCV) started in 2011. The aim of this study was to assess the antiviral efficacy and safety of DAA regimen, ombitasvir (OBV)/paritaprevir (PTV)/ritonavir (r) + dasabuvir (DSV) + ribavirin (RBV), in patients with chronic HCV infection, genotype Methods. The real-life data were collected. The study was multicentric and included seven infectious diseases and hepatology departments in Serbia. A total of 21 patients were enrolled in the OBV/PTV/r + DSV + RBV early access program, 20 of which were previously treated with pegylated interferon + RBV, while 1 was treatment-naive. All patients received the adequate doses of these antiviral drugs. RBV was not given to the patients with HCV genotype 1b infection according to the therapeutic protocol. For the majority of patient, the treatment duration lasted for 12 weeks. For the patients with liver cirrhosis, who were infected with HCV genotype 1a, the duration of treatment was 24 weeks. Viremia was assessed at four points in time: At baseline, 4 weeks after the treatment beginning (rapid viral response, RVR), 12 or 24 weeks after the treatment beginning (end of treatment response – ETR) and 12 weeks after the end of treatment (sustained viral response – SVR). SVR, as a confirmation of the absence of HCV was considered as endpoint of successful treatment. Results. Complete RVR, ETR and SVR were achieved in 64.71%, 85.71% and 95.24% of the patients, respectively. Only 3 patients had mild adverse effects which did not required dose reduction. Conclusion. The treatment of the patients with a chronic HCV infection with OBV/PTV/r + DSV + RBV resulted in excellent antiviral activity and tolerability. Apstrakt Uvod/Cilj. Era direktno delujućeg antivirusnog (DAA) režima lečenja bolesnika sa hroničnom hepatitis C virusnom (HCV) infekcijom započela je 2011. godine. Cilj rada bio je ispitivanje efikasnosti i bezbednosti DAA režima ombitasvir (OBV)/paritaprevir (PTV)/ritonavir (r) + dasabuvir (DSV) + ribavirin (RBV), kod bolesnika sa genotip 1 HCV infekci jom u Srbiji. Metode. U multicentričnu studiju je bilo uključeno sedam centara u Srbiji. Prikupljeni su podaci iz realnog života. U rani pristupni program OBV/PTV/r + DSV + RBV bio je uključen 21 bolesnik od kojih jedan nije prethodno lečen, dok je ostalih 20 prethodno lečeno pegilovanim interferonom i RBV. Svi bolesnici su dobijali odgovarajuće doze lekova. Bolesnici sa HCV genotipom 1b nisu dobijali RBV u skladu sa terapijskim protokolom. Za većinu bolesnika trajanje terapije je iznosilo 12 nedelja. Za četvoro bolesnika sa cirozom i HCV genotipom 1a trajanje terapije je iznosilo 24 nedelje. Viremija je određivana četiri puta: Pre početka terapije, 4 nedelje posle početka terapije (rapidni virusološko odgovor – RVR), 12 ili 24 nedelje nakon početka terapije (kraj terapije – ETR) i 12 nedelja nakon završetka terapije (stabilan virusološki odgovor – SVR). Postignut SVR kao potvrda odsustva virusne RNK u serumu, smatran je završnicom uspešnog lečenja. Rezultati. Kompletan RVR, ETR i SVR postignut je kod 64,71%, 85,71%, i 95,24% bolesnika sukcesivno. Samo 3 bolesnika imali su blage neželjene efekte koji nisu zahtevali korekciju doze lekova. Zaključak. Lečenje bolesnika sa hroničnom HCV infekcijom sa OBV/PTV/r + DSV + RBV pokazalo je odličnu antivirusnu aktivnost i podnošljivost