Estimation of uncertainty of trypsin inhibitor activity measurement in legume crops

Irradiation of legume seeds has emerged as an attractive alternative compared to conventional chemical treatments in seed production. Irradiation is also used for the decontamination of food and feed in order to increase the shelf-life of fresh and dry food materials. The effects of irradiation on nutritive and anti-nutritive factors such as trypsin inhibitors are usually reported together with the measurements obtained by using the quantitative analytical methods. The objective of this study was to measure trypsin inhibitor activity (TIA) of common bean cultivar Oplenac using the microtiter plate method and to identify factors that contribute to the uncertainty of TIA measurement according to the current Guide to the Expression of uncertainty in measurement (GUM). Dominant sources of uncertainty of TIA measurement were: absorbance measurements of sample and positive control reaction mixtures and preparation of the final sample solution using a graduated cylinder (V4). Absorbance measurement of sample reaction mixtures took 37.8% of the overall measurement uncertainty. Preparation of the final sample solution using a graduated cylinder (V4) and absorbance measurement of positive control reaction mixture contributed to the overall uncertainty with 35.1% and 15.8%, respectively. Acquired insight into factors that contribute to the uncertainty of TIA measurement gives directions for the improvement of TIA testing methods and TIA results management

Koncentracije elemenata u mišićnom tkivu dve vrste riba različitog trofičkog nivoa (uklija i štuka) u Dunavu kod Beograda

Industrijski i komunalni efluenti uzrok su visokih koncentracija nekih elemenata u rečnoj vodi. Procenjuje se da se u Srbiji oko 90% industrijskih otpadnih voda ispušta u vodotokove bez prethodne obrade. Koncentracije elemenata u tkivima riba pod uticajem su kako prisustva zagađenja staništa, tako i trofičkog položaja i veličine ribe. Koncentracije 15 elemenata analizirane su upotrebom ICP-OES u uzorcima mišićnog tkiva uklije i štuke uhvaćenih na ušću Save u Dunav, između oktobra 2011. i marta 2012. godine. Elementi Cd, Co, Li i Pb nisu detektovani u uzorcima. Jednofaktorska ANOVA je pokazala da postoje značajne razlike između mišićnog tkiva uklije i štuke u odnosu na koncentracije Ba, Cu, Fe i Zn. U mišićnom tkivu štuke, koja predstavlja piscivornu vrstu, detektovana je viša koncentracija Hg nego kod uklije, što ukazuje na biomagnifikaciju kroz lance ishrane, dok je kod uklije, kao obligatnog zooplanktivora, detektovana viša koncentracija Zn, što potvrđuje tendenciju negativne korelacije Zn sa trofičkim nivoom ribe. U mišiću uklije, od analiziranih elementa samo je kod Se uočena pozitivna korelacija sa totalnom dužinom tela (TL), dok je kod štuke uočena negativna korelacija Se sa težinom (W) i pozitivna korelacija koncentracije Al sa TL i W. Kod obe vrste ukupno je nađeno 20 korelacija (14 pozitivnih i 6 negativnih) između koncentracija elemenata u mišićnom tkivu. Kod uklije, najveći broj korelacija sa drugim elementima uočen je kod Mn i Sr. Kod štuke, pozitivna korelacija uočena je između Fe, Se i Zn, dok su sva tri elementa bila negativno korelisana sa Al, a Se i Zn pozitivno sa Mn i Sr

Koncentracije elemenata kod dve vrste riba sa različitim preferencijama staništa i ishrane (šaran i manić) u Dunavu kod Beograda

Akvatični ekosistemi se uobičajeno smatraju krajnjim recipijentima zagađenja toksičnim metalima, čiji izvori mogu biti prirodni ili, najčešće, antropogeni. Ova klasa zagađivača predstavlja značajnu pretnju za životnu sredinu i vrste koje žive u njoj, kao i potencijalnu pretnju za ljudsko zdravlje. Osim toksičnih elemenata, i elementi u tragovima, kao i esencijalni mikronutrijenti, mogu pokazivati toksična svojstva ako su prisutni u većim koncentracijama. Dunav je recipijent zagađenja oslobođenog oko industrijskih gradova koji se nalaze duž toka ove reke. Koncentracije metala u tkvima riba zavise od većeg broja faktora, među kojima veliki značaj imaju ishrana i stanište. Koncentracije 15 elemenata (Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Se, Sr i Zn) analizirane su upotrebom ICP-OES u uzorcima jetre i škrga jedinki šarana i manića uhvaćenih u Dunavu u blizini Beograda. Elementi Li, Ni i Pb nisu detektovani u uzorcima. Mann-Whitney U test je ukazao na postojanje značajne razlike između šarana i manića u odnosu na koncentracije nekoliko elemenata, i u jetri i u škrgama. PCA analiza je pokazala da šaran i manić formiraju dve odvojene grupe na osnovu koncentracije elemenata u analiziranim tkivima. Jetra šarana karakteriše se visokim koncentracijama Cd, Cu i Zn, a škrge visokom koncentracijom Zn, dok se kod manića i jetra i škrge karakterišu visokim koncentracijama As. U škrgama šarana detektovana je viša koncentracija Zn. Šaran živi na svim dubinama i preferira staništa sa gustom akvatičnom vegetacijom i potopljenim drvećem, a u pogledu ishrane predstavlja omnivornu vrstu koja konzumira i detritus. Odrasli manić je riba bentosa koj preferira kamenitu podlogu i oportunistički je predator. Različita ishrana šarana i manića može biti uzrok razlika u koncentracijama elemenata u jetri, dok razlike u preferencijama staništa mogu ukazati na razlike u škrgama

Sampling Error in Relation to Cyst Nematode Population Density Estimation in Small Field Plots

Cyst nematodes are serious plant-parasitic pests which could cause severe yield losses and extensive damage. Since there is still very little information about error of population density estimation in small field plots, this study contributes to the broad issue of population density assessment. It was shown that there was no significant difference between cyst counts of five or seven bulk samples taken per each 1-m(2) plot, if average cyst count per examined plot exceeds 75 cysts per 100 g of soil. Goodness of fit of data to probability distribution tested with chi(2) test confirmed a negative binomial distribution of cyst counts for 21 out of 23 plots. The recommended measure of sampling precision of 17% expressed through coefficient of variation (cv) was achieved if the plots of 1 m(2) contaminated with more than 90 cysts per 100 g of soil were sampled with 10-core bulk samples taken in five repetitions. If plots were contaminated with less than 75 cysts per 100 g of soil, 10-core bulk samples taken in seven repetitions gave cv higher than 23%. This study indicates that more attention should be paid on estimation of sampling error in experimental field plots to ensure more reliable estimation of population density of cyst nematodes

A Comparative Investigation of an in vitro and Clinical Test of the Bifidogenic Effect of an Infant Formula

The bifidogenic effect of an infant formula supplemented with inulin and fructooligosaccharides (4.0 g/l) was examined clinically and in vitro, and compared that of mature breast milk. In a 28-day clinical study, fecal samples of 21 infants, divided into two groups: one receiving the infant formula and the other breast milk, were microbiologically and biochemically examined. In the in vitro investigation, microbiological and biochemical changes in the infant formula and breast milk induced by the action of bifidobacteria isolated from infant feces were examined. There were no significant differences in the fecal numbers of lactobacilli, total aerobes, anaerobes or yeasts and fungi. In contrast, the bifidobacteria numbers in the stools increased significantly during the study in the infants receiving the supplemented formula. The comparative in vitro test showed that the bifidogenic effect was similar for infant formula and breast milk in terms of the number of bifidobacteria. Consumption of infant formula with added inulin and fructooligosaccharides stimulated the bifidogenic effect, both clinically and in vitro. The in vitro test can quickly and objectively determine the bifidogenic effect of infant formula and indicate their quality. However, a clinical test is necessary to determine the acceptance and biological value of infant formula

Spatial movement of the Wels catfish (Silurus glanis) in the Danube

Wels catfish (Silurus glanis, Linnaeus, 1758) is one of the most targeted species for recreational and commercial fishing in the Danube River, even though studies of behavior and movement patterns of Wels catfish in the Danube are rare. Wels catfish was caught downstream of Iron Gate II hydropower dam and tagged with an ultrasonic transmitter (Vemco Ltd, V16TP). Nine autonomous receivers (Vemco Ltd, VR 2W) recorded detections of spatial movement downstream of Iron Gate II dam between Serbia and Romania for almost two years, between the years 2015 and 2017. Our telemetry data found that Wels catfish exhibit relatively short movements within a maximum range (≈ 12 km), but as a territorial species most of the time it was recorded by the two receivers, close to the Iron Gate dam and location where it was caught. The longest displacement from the preferable place under Iron Gate II dam was migration to Romanian ship lock and turbines located in the right arm of the Danube River. Location under the river dam is already recognized as a place of aggregation of the fish and thus preference of predatory catfish is strongly connected with food availability. Our data revealed that dam and ship lock blocked further migration of this fish. The last signal received was during the winter 2017, which was a period with extremely low temperature and ice cover on the Danube River. Considering the fact that the ice displaced whole receiver deployment downstream the dam, we might conclude that the tagged catfish disappeared because of ice movement during the winter season. Results can be used for management ensuring habitat requirements and developing of restoration and conservation strategies

Review of sterlet (Acipenser ruthenus L. 1758) (Actinopterygii: Acipenseridae) feeding habits in the River Danube, 1694-852 river km

The aim of this work is to present the variation in the sterlet's (Acipenser ruthenus L. 1758) diet along the course of the River Danube, from 1694 to 852 river km. The diet of sterlet mostly comprised 12 bottom fauna taxa. Sterlet in the Danube feed mainly on larvae of Trichoptera, Chironomidae (Diptera) and Gammaridae (Amphipoda), with a reduction in food composition variability close to the Djerdap I dam and in the reservoir between the two dams. The other components of the diet were Corophium sp., Asselus sp., Mollusca, Oligochaeta, Annelida, Insecta, Nematoda and Hirudinea. The organisms typical of lithorheophilic and psammorheophilic biocoenoses play a considerable role in the diet of the sterlet. Composition of bottom fauna as food items varies due to changes in environmental conditions induced mainly by the construction of two dams: Djerdap I (943river km, 1970) and Djerdap II (863river km, 1984).Ministry of Education, Science and Technical development of the Republic of Serbia {[}173045