Adsorption of albendazole on activated carbon

Adsorpcija je metoda separacije uzrokovana privlačnim silama između adsorbensa i molekula u plinu ili otopini koje se adsorbiraju. Koristi se za uklanjanje malih koncentracija tvari iz velikog volumena onečišćenog plina, za uklanjanje mirisa, uklanjanje hlapljivih otapala, za obradu otpadnih voda itd. Cilj ovog rada bio je ispitati učinkovitost adsorpcije na praškastom aktivnom ugljenu, tj. uklanjanje albendazola iz MilliQ vode na različitu količinu aktivnog ugljena. Koncentracije albendazola bile su od 2,96 do 6,02 mg L^-1 što se mogu pripisati koncentracijama farmaceutika u otpadnim vodama farmaceutskih tvrtki ili retentatu tlačnih membranskih operacija. Šaržni postupak provodio se na masi aktivnog ugljena od 0,001 do 1 g. Pokazana je visoka vrijednost uklanjanja albendazola. Na najmanjoj korištenoj koncentraciji, 2,96 mg L^-1, već pri masi aktivnog ugljena od 0,01 g postignuto je uklanjanje veće od 99,9 %. Pri dvostruko većoj koncentraciji albendazola, 6,02 mg L-^1, uklanjanje je bilo smanjeno. Na istoj vrijednosti mase kao u prethodnom slučaju, učinkovitost uklanjanja bila je 55,7 %.Adsorption is a method of separation caused by the adhesive forces between adsorbents and molecules in gas or solutions which adsorb. It is used for the removal of small concentrations of substances in large volumes of polluted gases, for removal of scent, for removal of volatile solvents, for treatment of waste waters ect. The objective of this study was to examine the efficiency of adsorption on Powdered Activated Carbon, i.e the removal of albendazole from MilliQ water with various amounts of activated carbon. Concentrations of albendazole were from 2.96 to 6.02 mg L^-1 which can be attributed to the concentration of pharmaceuticals in waste waters of pharmaceutical companies or pressure membrane operations retentate. Batch adsorption was conductedon the masses of activated carbon from 0.001 to 1 g. A high values of pharmaceutical removal were demonstrated. With the smallest used concentration, 2.96 mg L^-1, and a mass of activated carbon of 0.01 g a removal rate of 99.9 % was accomplished. At a concentration of albendazole twice as large, 6.02 mg L^-1, the removal rate decreased. For the same value of mass as was in the previous case, effectiveness of removal was 55.7 %

Spectral and Dynamical Properties in Classes of Sparse Networks with Mesoscopic Inhomogeneities

We study structure, eigenvalue spectra and diffusion dynamics in a wide class of networks with subgraphs (modules) at mesoscopic scale. The networks are grown within the model with three parameters controlling the number of modules, their internal structure as scale-free and correlated subgraphs, and the topology of connecting network. Within the exhaustive spectral analysis for both the adjacency matrix and the normalized Laplacian matrix we identify the spectral properties which characterize the mesoscopic structure of sparse cyclic graphs and trees. The minimally connected nodes, clustering, and the average connectivity affect the central part of the spectrum. The number of distinct modules leads to an extra peak at the lower part of the Laplacian spectrum in cyclic graphs. Such a peak does not occur in the case of topologically distinct tree-subgraphs connected on a tree. Whereas the associated eigenvectors remain localized on the subgraphs both in trees and cyclic graphs. We also find a characteristic pattern of periodic localization along the chains on the tree for the eigenvector components associated with the largest eigenvalue equal 2 of the Laplacian. We corroborate the results with simulations of the random walk on several types of networks. Our results for the distribution of return-time of the walk to the origin (autocorrelator) agree well with recent analytical solution for trees, and it appear to be independent on their mesoscopic and global structure. For the cyclic graphs we find new results with twice larger stretching exponent of the tail of the distribution, which is virtually independent on the size of cycles. The modularity and clustering contribute to a power-law decay at short return times

Variability of Hydrological Parameters and Water Balance Components in Small Catchment in Croatia

Analysis of small catchment area in Croatian lowland with its hydrological characteristics in the period between 1981 and 2014 was carried out in order to define significance of change in hydrological and meteorological parameters (precipitation, air temperatures, and discharges) and water balance components (deep percolation and potential evapotranspiration). There was no significant land use change in the observed period, so all changes in hydrological processes can be considered to be without human impact in the last 35 years. Application of RAPS (Rescaled Adjusted Partial Sums) on all data series distinguished two subperiods with different length but the same behaviour. The first subperiod was a period characterised by the decrease, starting in 1980 and finishing between 1991 and 1995, while the second one was a period characterised by the increase of parameters in all analyses, starting between 1991 and 1995 and finishing in 2001. In comparison to the analysis of climate change impacts per decade, this approach is much more appropriate and gives insight into variations throughout the entire observed period. The most variable but not significant parameters are precipitation and discharges, especially in the second subperiod which has a major impact on occurrence of hydrological hazards such as droughts and floods and makes great pressure and responsibility on water management system

Kloniranje gena za ugljeni hidrat oksidazu iz biljke Lactuca sativa u kvasce saccharomyces cerevisiae i Pichia pastoris

We have cloned the gene for carbohydrate oxidase (CHO) from Lactuca sativa in two species of yeasts (Saccharomyces cerevisiae and Pichia pastoris). The synthetic gene Department for Plant Physiology, Institute for Biological Research 'Siniša Stanković', drate oxidase (1821 bp) from L. sativa cloned into the vector pUC57 and inserted into plasmids pYES2 and pGAP using Escherichia coli DH5α strain. The P. pastoris strain X-33 and the S. cerevisiae strain InvSC1 were used for extracellular expression of CHO. After transformation of P. pastoris X-33 with CHO-pGAP construct none of the colonies showed CHO activity. Two samples displayed a band which did not exist in the sample with the empty vector similar to the molecular weight of CHO. The S. cerevisiae stran InvSC1 has been also transformed with CHO-pYES constructs. Three colonies grew on the plate with cells transformed with the construct. One of the samples showed a band corresponding to about 110 kDa, but no CHO activity was recorded in this case either. Cloning of the foreign genes and heterologous expression in yeasts is widely used in biotechnology, but sometimes can be very dependent on the gene sequence and strain used. In order to obtain active CHO enzyme the further studies on purification and refolding of expressed protein are necessary.Ugljeni hidrat-oksidaza (CHO) iz zelene salate (Lactuca sativa) je enzim koji je do danas nedovoljno ispitan. Vrlo se malo zna o njegovoj strukturi i funkciji. CHO pripada velikoj familiji ugljenihidrat-oksidaza, koje oksiduju šećere. Svaki od članova ove velike familije dobio je ime po supstratu koji oksiduje. Oksidaze iz ove familije enzima imaju kako sličnu ulogu tako i sličnu strukutru. Sve ili većina ovih enzima su monomeri, čiji se polipeptidni lanac uvija u dva domena. Jedan od domena vezuje flavinski kofaktor, a drugi domen je supstrat vezujući. Većina njih oksidaciju supstrata vrši po takozvanom ping-pong mehanizmu. Sve oksidaze iz karbohidrat-oksidaza familije, pa među njima i enzim koji je predmet ove studije (CHO), danas su našle veliku primenu u industriji. CHO se može primenjivati kako u medicinskoj djagnostici, konkretno u biosenzorima za određivanje glukoze u krvi, u prehrambenoj industriji, poljoprivredi, proizvodnji hleba, deterdženata i u raznim drugim industrijskim oblastima. Problem sa ovim enzimom, kao i sa ostalim članovima ove familije, jeste niska koncentracija u prirodnim izvorima. Zato su danas razvijene različite metode rekombinantne tehnologije, kojima se dobijaju ovi enzimi. U ovom radu opisano je kloniranje gena za CHO iz zelene salate u dve vrste kvasaca (Saccharomyces cerevisiae i Pichia pastoris). Sintetički gen za CHO (1821 bp) iz zelene salate kloniran je u vektor pUC57. Escherichia coli soj DH5α korišćen je za kloniranje gena i održavanje plazmida. P. pastoris soj X-33 i S. cerevisiae soj InvSC1 korišćeni su za ekstracelularnu ekspresiju CHO. Aktivnost CHO određena je ABST esejom, a promena absorbance merena je na 405 nm. Potvrda prisustva enzima rađena je na DNK agaroznoj elektroforezi i SDS-PAGE. Posle transformacije P. pastoris X-33, nijedan od klonova nije pokazivao aktivnost CHO. Posle prve fermentacije, kolonije su testirane na SDS-PAGE. Kako su dva uzorka pokazala trake, koje ne postoje na praznom vektoru, ove trake bi mogle odgovarati željenom enzimu, CHO. Traka se nalazi na molekulskoj masi koja je veća od teoretske (više od 120 kDa). Enzim bi mogao biti glikolizovan i zbog toga pokazivati ovako velike vrednosti za molekulsku masu. S. cerevisiae soj InvSC1 transformisan je konstruktom CHO-pZES. Posle 24 sata, tri kolonije su porasle na ploči na kojoj su bile ćelije transformisane pomenutim konstruktom. Uzorci su testirani na SDS-PAGE. Jedan uzorak je pokazao traku na oko 110 kDa, ali aktivnost CHO nije potvrđena takođe. Cilj ove studije je bio kloniranje CHO u kvascima S. cerevisiae i P. pastoris, kao i njena ekspresija u ovim, danas široko primenjivanim ekspresionim sistemima

Biomass production as renewable energy resource at reclaimed Serbian lignite open-cast mines

The main goal of this paper is the overview of the scope and dynamics of biomass production as a renewable energy source for substitution of coal in the production of electrical energy in the Kolubara coal basin. In order to successfully realize this goal, it was necessary to develop a dynamic model of the process of coal production, overburden dumping and re-cultivation of dumping sites by biomass planting. The results obtained by simulation of the dynamic model of biomass production in Kolubara mine basin until year 2045 show that 6870 hectares of overburden waste dumps will be re-cultivated by biomass plantations. Biomass production modeling point out the significant benefits of biomass production by planting the willow Salix viminalis cultivated for energy purposes. Under these conditions, a 0.6% participation of biomass at the end of the period of intensive coal production, year 2037, is achieved. With the decrease of coal production to 15 million tons per year, this percentage steeply rises to 1.4% in 2045. This amount of equivalent tons of coal from biomass can be used for coal substitution in the production of electrical energy

Thermal kinetic analysis of the spent mushroom substrate and hydrochar

A carbon-rich product, hydrochar, was synthesized by hydrothermal carbonization (HTC) of spent mushroom substrate (SMS), at temperature of 260 °C. The thermal kinetic analysis has shown that hydrothermally treatment improve the combustion behavior of hydrochar. The kinetic parameters were determined by Kissinger and Ozawa methods. The SMS-260 had a significantly lower activation energy compared to the SMS, which means that this hydrochar needs a smaller amount of energy to start combustion. Generally, the preliminary results show that HTC is an effective way to transform SMS into alternative solid biofuel

Optical and antioxidative properties of 5-(2,6-Dimethylphenyl)- 6-Hydroxy-4-Methyl-2-Oxo-1,2-Dihydropyridine-3-Carboxamide

A new heterocyclic azo dye 5-(2,6-dimethylphenyl)-6-hydroxy-4-methyl-2-oxo-1,2- dihydropyridine-3-carboxamide was synthesized and structurally characterized by elemental analysis, FTIR, 1H and 13C NMR spectroscopy techniques. These analysis have confirmed that synthesized dye exists in the tinctorial strongest tautomeric form, hydrazone form. The dye is characterized by reflection spectrum, while absorption and emisson spectra are recorded in nine different solvents. The antioxidant activity of the synthesized dye has been chemically tested and has been shown to have great potential as an antioxidant molecule

Adsorption of Pb2+ ions on gamma irradiated plum pomace biochar

Removal of heavy metals is important because of their toxic effects on living organisms and unwanted anthropogenic effects. Biochar is suitable as an adsorbent of heavy metals due to its advantages such as various sources of biomass, a large number of microporous channels and surface functional groups, as well as due to its economic viability. There is no data about the plum pomace biochar usage as adsorbent for lead removal. In this study, the plum pomace biochar modified with gamma irradiation (IrPP) is used for the removal of Pb2+ ions from the aqueous solution. The SEM micrographs revealed that surface morphology of plum pomace is suitable for metal adsorption. The results of adsorption kinetics demonstrated that the removal process of Pb2+ ions onto IrPP follows a pseudo-second kinetic model, which is confirmed by a better agreement between qe,cal=227 mg g–1 and qe,exp=224 mg g–1 . Therefore, based on preliminary research, it can be concluded that IrPP originating from biowaste is a promising, eco-friendly sorbent of heavy metal from wastewater

2-OXO-1,2,3,4-tetrahydropyrimidine-azo-pyridone dye : a potential application as new green-emitting fluorescent probe

Molecular imaging is a relatively new research field, which has demonstrated great potential, especially in clinical oncology – from drug development to cancer early detection. The key of fluorescence imaging is the construction of fluorescent probe which is composed of two parts, the recognition groups to recognize cancer cells, and fluorophores to signal the recognition events. In this research, the structure of new fluorescent azo dye based on 2-oxo-1,2,3,4-tetrahydropyrimidin and 2-pyridone moieties has been reported. The absorption and emission properties of the investigated azo dye have been studied using UV-Vis and fluorescence spectroscopy. The obtained results suggest that studied dye meets the requirements for new green-emitting fluorescent probe, suitable for further application in biomedical researches