Antioxidant Effects of Glechoma hederacea as a Food Additive

The antioxidant properties of Glechoma hederacea L. (Lamiaceae), of Serbian origin, were studied in respect to its potential use in foodstuffs. Ethanol-water (8:2, v/v) and purified ethyl acetate extracts of the plant were found to possess significant antioxidant activity. Tests were performed on two different substrates, prime steam pork lard and active-carbon-treated edible sunflower oil, using Schaal oven test storage conditions at 60 degrees C. The ethanol-water and purified ethyl acetate extracts of G. hederacea showed strong concentration-dependent antioxidant activity. On the contrary, under the Rancimat method conditions at 120 degrees C, the ethanol-water extract showed significantly stronger antioxidant activity, in comparison with the other tested extracts. All activities were compared with commercial antioxidants, such as BHA and a tocopherol mixture, respectively. For the first time, the activity of the flavonol quercetagetin was determined

Impact of the process of polymerization of polyol and toluen diisocyanate on the environoment

The aim of this study was to investigate the impact of the process of polymerization of polyiol and tolyendiisocyanate on the environoment. Toluene diisocyanates are important industryal intermediates used in conjunction with polyether and polyester polyols as coreactants polyurethane foams, paints, varnishes, elasomers and coatings. This presentation summarizes existing information on the release and behavior of the process of polymerization of polyol and toluen diisocyanate on the environment. A major reaction of TDI in the environoment is formation of solid inert polyureas from reaction with water. In use, TDI is reacted with polyols to form many different polyurethane products. Polyurethanes have been show to be stable in the environment and in disposal have no adverse impact on municipal waste handling processes, landfills or incineration.Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200

Modified eggshell catalyst for transesterification of sunflower oil: The effects of catalyst loading on FAMEs content

Modified highly active CaO catalyst (ESCHC-600) derived from waste chicken eggshells were prepared and used in the transesterification of sunflower oil. Eggshells were subjected to calcination-hydration-calcination (CHC) cycles described in detail previously [1]. After CHC treatments, highly active CaO was obtained, which indicates its great potential for biodiesel synthesis. The transesterification reaction was carried out in a batch reactor at 60 ºC, methanol to oil molar ratio of 12:1, and different catalyst concentrations ranging from 2 to 8 wt%. Fatty acid methyl esters (FAMEs) content was determined by the HPLC analytical technique. The highest triacylglycerols (TAGs) conversion to FAMEs was achieved at a catalyst loading of 4 wt% (Fig. 1a). A further increase in catalyst loading (> 4 wt%) led to a decrease in TAGs conversion. The higher catalyst loadings (6 and 8 wt%) limited mass transfer of the TAGs and reaction products (FAMEs, DAGs and MAGs) due to the higher reaction mixture density and viscosity of the complex multiphase system. Compared to raw eggshell calcined at 900 ºC (ES-900) (Fig. 1b), the synthesized ESCHC-600 catalyst showed a higher activity, which could be attributed to a more favourable pore structure of CHC treated catalyst and better availability of the active sites.Conference of the Young Chemists of Serbia, Belgrade, 2nd November 201

The B group vitamins and mineral elements in the selective removal of wheat kernel layers

The objective of this study was to investigate how selective removal of the surface layers of whole wheat grains by abrasive scouring affects the distribution of mineral elements (macronutrients, micronutrients and trace elements) and the B group vitamins (thiamin, riboflavin pyridoxine, pantothenic acid and niacin) in three soft winter wheat varieties (Partizanka, Novosadska rana and Lasta). Although representing technologically different quality classes of wheat, the varieties were not significantly different in the B group vitamin contents, except for pyridoxine. Whole grains of all varieties exhibited very similar scouring behavior in reduction of vitamins: the most intensive investigated regime only slightly, but not significantly reduced the concentration of the B group vitamins. The nutritive value of scoured wheat grains with regard to the B group vitamins was preserved. The investigated minerals were: Na, K, Ca, Mg, N4n, Fe, Cu, Zn, Ni, Cr, Se, Pb and Cd. The concentrations of minerals in scoured wheat grains were significantly reduced, dropping on average to 65% of the initial values for macro and 55% for microelements. The change of concentrations with the duration of applied treatment followed different patterns for different elements. Furthermore, a different pattern of the change for the same element in different wheat varieties was noticed. This might be due either to different mechanical properties of bran and bran layer interfaces or genotypic variability in distribution of elements in wheat grain. Severe reduction in Pb concentrations was achieved leading to improvement of whole-wheat food safety

Rumunske verske zajednice u Banatu: prilog proučavanju multikonfesionalnosti Vojvodine

ROMANIAN RELIGIOUS COMMUNITIES IN BANAT A contribution to the study on multiconfessionality of Vojvodina Abstract The Romanian ethnic minority in the Serbian Banat traditionally belongs to the Orthodox religion, but during the last decades of the 19th and the first decades of the 20th century new religions appeared – first the Greek Catholicism, as well as several Neo-Protestant confessions, such as the Church of the Nazarene, the Adventist and the Pentecostal Church. The number of the Neo-Protestant believers within the Romanian community increased during the first half of the 20th century, but after that came to a standstill and even decreased due to the general decline of the Romanian population in the Serbian Banat. Affiliation with Neo-Protestantism does not hinder the preservation of the national identity of the Romanians in Banat, as these believers are constituent parts of the confessional reality of the Romanians of Vojvodina and Serbia. After a detailed insight into the identity of the Romanians in Banat, the first chapter of the monograph offers an overview of their confessional life, followed by the history of the development of the Greek Catholic Church, Nazarene, Adventist and Pentecostal communities, with a brief outline of the Jehovah Witnesses. The confessional life of the Romanians in Banat is shaped by the fact that most of them belong to the Romanian Orthodox Church, but also, in smaller numbers, to Neo-Protestant and the Greek Orthodox Church. The Neo-Protestant confessions, which appeared with the Romanians in Banat in the last decades of the 20th century (the Adventists, Baptists and Pentecostals), led to the enrichment of the confessional life in the region, but also to the decrease in the number of Orthodox believers. The presence of these communities in the multiethnic and multiconfessional nowadays world has become a reality which does not obstruct the preservation of the ethnic identity of the Romanian minority in Banat, but, on the contrary, may stand for the expression of free choice of each and every citizen.The second chapter is focused on the Nazarene community, the first Neo-Protestant community that had a great number of believers in the end of the 19th and the beginning of the 20th century among the Serbs and Romanians in Banat. In spite of the fact that, at the beginning of the 20th century, the Nazarenes used to be a very large community, due to unfavorable socio-historical conditions, their number has constantly decreased. This chapter puts emphasis on the position of minority religious communities, and debates the problem of the so-called double minorities, as well as hidden minorities. Through a brief outline of the creation of the Nazarene movement and its spread to the region of nowaday Vojvodina, certain basic Nazarene ideas are presented and the specific features of Nazarenes as first Neo-Protestants in the region are stated here. The second part of the chapter offers a short historical overview of the oldest confession of the Romanians living in Banat, i.e. the Romanian Orthodox Church, with a focus on the appearance of the evangelistically oriented movement of the Army of the Lord. According to the results of the field research conducted by the author, which are presented in the book as transcripts of conversation, elements of cultural identity of the Romanian Nazarenes are also analyzed. The basic assumption is that, due to double minority position the Romanian Nazarenes, they have remained more closed and conservative and therefore more numerous in comparison to Serbian Nazarenes. The problem of the “closed field” is also tackled here, as well as various forms of risks when working in the field with micro- communities. The third chapter situates itself, from a methodological standpoint, at the crossroad of linguistic anthropology and pragmalinguistics. Such a methodological pluralism has imposed itself after a long field research practice of integrative recordings of maximally broad interview contexts. The researcher starts from the idea that the interviewed persons take part voluntarily in the research, since they want to be heard by others, but she agrees that this is only partially true and does not refer to all the subjects. Having in mind that it is grounded on the results of field work, this chapter incorporates integral transcripts of the appropriate parts of conversation, without any subsequent interventions of the author. Eight passages of conversations with the representatives of the Romanian language and culture in Vojvodina have been selected as the starting point and basis of the analysis. These are conversations with the Romanians in Banat, held between 2004 and 2008, and one interview in the Serbian language, made in 2011 with a Roman Catholic Bayash from Sonta, Bačka region. Аn attempt has been made for transcripts to preserve the specific features of the idiolect of the interviewed subjects as much as possible. Only epistemological elements of the applied field work methodology have been chosen, which reflect the concept of serendipity. As for the content of the interviews, the author opted for the analysis of the ideological Neo- Protestant elements, as well as of the local oral history regarding the age of interconfessional cohabitation in the village of Markovac

Proteinski sastav tofua korigovanog kvaliteta

Soybeans are an inexpensive, high-quality protein source. Soybeans have long been a staple of the human diet in Asia, especially as tofu, which is prepared from soymilk. In this study, tofu was made using a new production method which includes hydrothermal cooking (HTC) and rennin-pepsin coagulant. The effects of the addition of gallic acid to the slurry during tofu processing were studied. Tofu was made from two soybean genotypes: Lana and Balkan. The observed genotypes are characterized by relatively high content of total proteins in flour, from 45.88% to 48.83%. The prepared tofu samples are characterized by extremely high content of total proteins (52.17% - Lana tofu and 56.08% - Balkan tofu). The presence of gallic acid significantly affects the solubility of tofu protein. The applied modifications of traditional procedure of tofu production significantly improved sensory properties of soybean protein products.Tofu je želirani proteinski proizvod, koji se dobija koagulacijom zagrejanog sojinog mleka. Potrošačima naše populacije ne odgovara aroma 'zelenog zrna', takozvani 'leguminozni miris i ukus', koji se oseća u proizvodima soje pripremljenim na tradicionalni način. Sa namerom poboljšanja arome dobijenih sireva, pripremljen je tofu primenom hidrotermičkog tretmana i enzima za koagulaciju mleka (himozin-pepsin) uz dodatak galne kiselina, koja je jak antiseptik i antioksidant. Zahvaljujući visokom sadržaju ukupnih proteina sojinog semena (45,88-48,83% u obezmašćenom brašnu) i pripremljeni tofu se karakteriše visokim sadržajem ukupnih proteina (52,17% s.m.- Lana tofu i 65,08 % s.m. - Balkan tofu). Postupak dodatka galne kiseline menja sadržaj rastvorljivih proteina (27,48% - Lana tofu i 41,55% - Balkan tofu) koji se značajno razlikuje u odnosu na uzorke bez nje (14,20% - Lana tofu i 28,88% - Balkan tofu). Poliakrilamidnom-gel elektroforezom ekstrakta tofua pripremljenog uz dodatak galne kiseline razdvojen je veći broj komponenata, koje se ne uočavaju na elektroforegramima tofua nemodifikovanog kvaliteta. Gasnohromatografskom analizom isparljivih komponenata tofua registrovan je uglavnom acetaldehid, tako da je postignut cilj ublažavanja legulinoznog mirisa. Poboljšanje senzornih karakteristika potvrđuju i povoljne senzorne ocene koje su dobili uzorci pripremljeni sa galnom kiselinom (3,65 - Lana tofu i 3,87 - Balkan tofu)

Aceton kao alternativno ekstrakciono sredstvo za izdvajanje biljnih ulja

Hexane, mainly due to its reasonable price, has been used as the principal solvent for the commercial extraction of oilseed since the forties of the 20th century. Over the past 40 years, factors, such as product quality and process safety, and environmental regulations, have resulted in the search for an acceptable alternative solvent. Acetone, as an extraction solvent has many ecological and physical advantages over hexane. However, to replace hexane, acetone would have to be economically and technologically acceptable. This study demonstrates a possibility of soya bean oil extraction by acetone (0-30% water), as an alternative solvent, in comparison with the conventional method. The water solubility of acetone provides some advantages and disadvantages vs. hexane. The oil extraction efficiency of acetone depends directly upon its water content. Water content above 10% results in significant decrease in its natural oil extraction ability. The content of free fatty acids (FFA) and total extractables in oil depend directly upon the water content. Insoluble, high-energy phosphatides and gums remain in the extracted meal. The nitrogen content increased in the extracted meal with the increased water content in acetone. Further studies within this field will be of a great importance in determining whether acetone can be used as an extraction solvent on a large scale.Heksan je zbog pristupačne cene bio glavni rastvarač za ekstrakciju ulja iz uljarica još od 1940 godine. U poslednjih trideset godina, faktori kao što su kvalitet proizvoda, bezbednost i ekološke regulative uslovili su intenzivno istraživanje sa ciljem da se pronađe prihvatljivi alternativni rastvarač. Aceton, kao potencijalni alternativni rastvarač, ima niz ekoloških i fizičkih prednosti u odnosu na heksan, ali da bi u potpunosti zamenio heksan trebalo bi da bude i ekonomski i tehnološki prihvatljiv. Ovim istraživanjem utvrđena je mogućnost primene acetona (0-30% vode) kao alternativnog ekstrakcionog sredstva za izdvajanje ulja soje, a u poređenju sa klasičnim načinom ekstrakcije. Rastvorljivost acetona u vodi pružila je neke prednosti, ali ima i mana u odnosu na heksan. Efikasnost ekstrakcije ulja iz soje bila je u direktnoj vezi sa sadržajem vode u acetonu, pri čemu je udeo vode iznad 10% uticao na smanjenu moć ekstrakcije i manji prinos ulja iz soje. Sadržaj slobodnih masnih kiselina (SMK) i ukupnih rastvorljivih materija zavisio je direktno od sadržaja vode. Nerastvorljivi visokoenergetski fosfatidi i gume zaostajali su u sojinoj sačmi. Sadržaj azota u sačmi rastao je sa povećanjem sadržaja vode u acetonu. Dalja istraživanja u ovoj oblasti su od značaja kako bi se utvrdilo da li aceton može biti upotrebljen kao ekstrakcioni rastvarač u širim razmerama

Određivanje nutritivne vrednosti pšeničnog hleba sa dodatkom mešavine semena kvinoje, heljde i tikve

The purpose of this research was to blend quinoa (Chenopodium quinoa Willd.), buckwheat (Fagopyrum esculentum Möench) and pumpkin (Cucurbita pepo L.) seed kernels at 40% level with wheat flour and to examine the effect of this blend on nutritional and sensory quality and also energy values of the pan bread. Hydrothermal preparation of these supplements is included. Chemical composition of the investigated materials, wheat bread and supplemented bread, was determined using relevant AOAC methods. Chemical composition of supplemented bread with an increase in protein, oil and crude fiber was superior in comparison with control wheat bread. Sensory properties of supplemented bread such as specific volume, appearance, crust and crumb texture, aroma-odor and color were evaluated and found excellent.Cilj rada je bio da se ispita mogućnost proizvodnje pšeničnog hleba sa dodatkom semena kvinoje, heljde i tikve do nivoa od 40%. Kvinoja (Chenopodium quinoa Willd., familija Amaranthaceae) je pseudocerealija. U ovom radu je korišćena danska sorta KVL 37, gajena u okolini Beograda. Domaća komercijalna semena heljde (Fagopyrum esculentum Möench) i tikve (Cucurbita pepo L.) su nabavljena u lokalnoj radnji zdrave hrane. U ovom radu su prikazani hemijski sastavi prečišćenog semena kvinoje, kao i semena heljde i tikve. Heljda i kvinoja su odabrane zbog toga što ne sadrže gluten, a imaju visok sadržaj kvalitetnih proteina. Očišćeno seme tikve (golica) je odabrano zbog toga što sadrži veliki procenat nutritivno i zdravstveno vrednog ulja i proteina. Analizirane su hemijske i tehnološke osobine mešavine ovih semena i pšeničnog brašna, kao i mogućnost njihove primene u proizvodnji hleba u kalupu. Određen je hemijski sastav i nutritivna energetska vrednost pšeničnog hleba pripremljenog sa dodatkom 15% semena kvinoje, 15% semena heljde i 10% golice. U odnosu na kontrolni pšenični hleb, obogaćeni hleb je sadržao 6% više proteina, 3,8% više ulja i oko 5% više sirovih vlakana. Sadržaj skroba u obogaćenom hlebu je bio niži za oko 8%. Energetska vrednost obogaćenog hleba je porasla za oko 150 kJ/100 g. Obogaćeni hleb je imao dobru specifičnu zapreminu i odlične senzorne osobine. Pokazano je da je ispitivana mešavina pšeničnog brašna i odabranih semena pogodna za proizvodnju hleba u kalupu, povećane nutritivne vrednosti

Kvalitet života laringektomisanih bolesnika u Srbiji

Introduction/Objective Total laryngectomy is a very mutilating operation and it leads to drastic changes in life quality. The purpose of this study was to examine factors of importance to the laryngectomized patients' quality of life and to evaluate characteristics of esophageal voice and speech. Methods The study was conducted at the Clinic of Otorhinolaryngology and Maxillofacial Surgery, at the Clinical Center of Serbia (Belgrade, Serbia), during the period between March 2012-2015. The study included 223 patients diagnosed with laryngeal cancer, who underwent total laryngectomy. The total of 168 laryngectomized patients were provided with phoniatric rehabilitation. Results The quality of life was significantly better for those laryngectomized patients who did undergo phoniatric rehabilitation. By means of intensive phoniatric rehabilitation the esophageal voice and speech was established in 86.3% of laryngectomized patients registered by objective acoustic analysis. Rehabilitated laryngectomy patients had a significantly lower presence of voice handicap sense (VHI: 19.57 ± 7.35) and expressed significantly lower symptoms of depression and anxiety (PHQ-9: 3.8 ± 4.2; GAD-7: 3.4 ± 4.2). Cronbach's alpha coefficient was above 0.7 EORTC QLQ-C30 on three levels of Likert scales: the scale of physical and emotional functioning and fatigue; as well as EORTC QLQ-H&N43 questionnaire: the symptoms of head and neck pain, speech, swallowing and eating problems and body image. Conclusion Significantly improving the quality of life of laryngectomized patients was achieved by a multidisciplinary rehabilitation. Phoniatric rehabilitation carried out in a planned and systematic way is the most efficient rehabilitation of laryngectomized patients.Uvod/Cilj Totalna laringektomija, kao veoma mutilantna operacija, dovodi do drastičnih promena u kvalitetu života. Cilj ove studije je da istraži faktore od značaja za kvalitet života laringektomisanih bolesnika i da proceni karakteristike ezofagusnog glasa i govora. Metode Istraživanje je sprovedeno u Klinici za otorinolaringologiju i maksilofacijalnu hirurgiju Kliničkog centra Srbije u Beogradu, u periodu od marta 2012. do marta 2015. godine. Ispitivanjem je bilo obuhvaćeno 223 bolesnika kojima je zbog verifikovanog karcinoma larinksa učinjena totalna laringektomija i sprovedena fonijatrijska rehabilitacija kod 168 laringektomisanih bolesnika. Rezultati Kvalitet života laringektomisanih bolesnika kod kojih je sprovedena fonijatrijska rehabilitacija je značajno bolji od onih koji nisu imali fonijatrijsku rehabilitaciju. Intenzivnom fonijatrijskom rehabilitacijom je uspostavljen ezofagusni glas i govor kod 86,3% laringektomisanih bolesnika, koji je registrovan objektivnom akustičkom analizom. Rehabilitovani laringektomisani bolesnici imaju značajno niže prisustvo hendikepa zbog glasa (VHI: 19,57 ± 7,35) i značajno niže izražene simptome depresije i anksioznosti (PHQ-9: 3,8 ± 4,2; GAD-7: 3,4 ± 4,2). Kronbahov α koeficijent je bio iznad 0,7 na tri skale upitnika EORTC QLQ-C30: fizičko funkcionisanje, emocionalno funkcionisanje i umor, kao i kod pet skala QLQ-H&N43 upitnika: bol u glavi/vratu, problemi sa gutanjem, problemi sa govorom, problemi pri jelu i slika o sebi. Zaključak Značajno poboljšanje kvaliteta života laringektomisanih bolesnika postiže se multidisciplinarnom rehabilitacijom. Fonijatrijska rehabilitacija, koja se sprovodi planski i sistematično, predstavlja najekonomičniji način rehabilitacije laringektomisanih bolesnika

Modelovanje, analiza i dizajn destilacionih sistema

The analysis and sizing of the distillation column for the separation of n-heptane-n-octane mixture were conducted using a traditional method for modeling and describing distillation systems, combined with modern software systems. Basic parameters were obtained by using rigorous separation and calculation procedures for the separation of the mixture used. These parameters describe distillation process, as well as basic dimensions and physical and hydro-dynamic parameters of the distillation column. Analytical and numerical methods were used for the analysis, modeling, sizing and operation control of the system. The previously used calculation methods were verified by developing the program for the case of the binary mixture. The values, obtained in this program were used for further description of the system, as well as sizing and determining basic physical and hydro-dynamic properties such as column diameter, and pressure drop. The key parameters describing this system are optimal reflux, minimum reflux, number of theoretical stages and minimum number of theoretical stages. Changes of the number of stages, reflux and column diameter were monitored as a function of mixture composition, as well as flow of the mixture at entrance of the column. Key words: distillation of binary mixture, rigorous calculation procedures, design methods, distillation columnsTradicionalne metode modelovanja i opisivanja destilacionih sistema, u kombinovanju sa savremenim softverskim paketima, poslužile su za analizu rada i dimenzionisanje destilacione kolone za razdvajanje binarne smješe nheptan-n-oktan. Primjenom rigoroznih postupaka razdvajanja i proračuna za razdvajanje smješe, praćeni su osnovni parametri, koji opisuju tok destilacije, kao i osnovne dimenzije destilacione kolone sa ventilskim podovima i osnovne fizičke i hidro-dinamičke parametre (dijametar kolone i pad pritiska). Za analizu, modelovanje, dimenzionisanje i kontrolu rada ovog sistema korišćene su grafičke, analitičke i numeričke metode. Razvijanjem programa verifikovane su ranije korišćene metode proračuna, a vrijednosti dobijene proračunom su poslužile za dimenzionisanje kolone. Ključni parametri koji opisuju ovaj destilacioni sistem su radni refluksni odnos i minimalni refluksni odnos, broj teorijskih podova i minimalni broj teorijskih podova. Promjene navedenih veličina praćene su u funkciji sastava smješe, kao i protoka smješe na ulazu u destilacionu kolonu