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A neglected natural source for targeting glioblastoma
No full textThe cytotoxicity of the methanol extract of the freshwater sponge Ochridaspongia rotunda (Arndt, 1937) (Malawispongiidae) was evaluated by MTT assay at in vitro conditions against three brain tumour cell lines (Neuro-2A, U-251 MG and U-87 MG). The extract was actually found to be most effective against the malignant glioma U-251 MG cells reaching a promising IC50 value of 1.87 +/- 0.09 mu g/mL at 96 h. However, it exhibited only a bit of cytotoxicity (IC50 321.14 +/- 11.29 mu g/mL, 96 h) towards the normal cells. Also, this sponge extract was 5-fold more selective for U-251 MG versus U-87 MG cells. Finally, monitoring genotoxicity at chromosomal level using the micronucleus test practically revealed lack of any significant toxicity of O. rotunda extract, compared to doxorubicin. [GRAPHICS]
Modelling of extrusion process for evaluation of spelt wholegrain snack expansion
No full textU današnje vreme, povećana proizvodnja i upotreba speltinog integralnog brašna u ishrani ljudi povećava potrebu za definisanjem i karakterizacijom snek proizvoda od ove sirovine. Male promene u ulaznim procesnim parametrima tokom procesa ekstrudiranja utiču ne samo na izlazne procesne parametre nego i na kvalitet proizvoda ekstrudiranja. Stoga, ispitan je uticaj parametara ekstrudiranja, uključujući protok materijala (15-25 kg/h), učestanost obrtanja pužnice (250-750 o/min) i vlažnosti materijala (15-25%) na stepen ekspanzije snek proizvoda od speltinog integralnog brašna. Speltino integralno brašno ekstrudirano je primenom dvopužnog ekstrudera Bühler BTSK 30/28D (Bühler, Uzwil, Švajcarska). U ovoj studiji matematička analiza započinje razvojem polinoma drugog stepena (SOP) kako bi se izvršila analiza varijanse (ANOVA) za rangiranje ulaznih promenljivih u odnosu na indeks ekspanzije. Vrednosti za indeks ekspanzije predviđene su korišćenjem ANN koji je kasnije primenjen za računanje relativanog uticaja nezavisnih promenjivih na zavisnu promenjivu. Povećajući vlažnost ulaznog materijala i učestanosti obrtanja pužnice tokom ekstrudiranja dolazi do velikog smanjenja odnosno povećanja ekspanzije ekstrudata, respektivno. Sa ciljem da se dobije najveći stepen ekspanzije (1,93) korišćeni su sledeći parametri ekstrudiranja učestanosti obrtanja pužnice (750 o/min), vlažnosti polaznog materijala od 20% i protoka materijala od 20 kg/h. Na osnovu rezultata dobijenih korišćenjem Yoonovog modela pokazano je da na stepen ekspanzije najveći uticaj ima uestanost obrtanja pužnice.The effect of extrusion parameters, including feed rate (15-25 kg/h), screw speed (250-750 rpm) and feed moisture (15-25%) on the expansion index of spelt wholegrain snack products was investigated. Wholegrain spelt flour was extruded using co-rotating twinscrew extruder (Bühler BTSK 30/28D, 7 sections, length/diameter ratio = 28:1, Bühler, Uzwil, Switzerland). The obtained data demonstrate that increased feed moisture leads to a decrease in the expansion of extrudates. Increasing in screw speed resulted in higher elasticity, which has resulted in the greater expansion index. The following operating conditions: screw speed (750 rpm), feed moisture (20%) and feed rate (20kg/h) provided the highest expansion index (1.93). The screw speed has the greatest positive influence on the expansion index obtained by Yoon's model
Extraction kinetics modeling of amaranth seed oil supercritical fluid extraction
No full textUlja biljnog porekla danas privlače pažnju širom sveta zbog nutritivnog kvaliteta i zdravstvenih dobrobiti. Seme amaranta sadrži ulje sa važnim hranljivim svojstvima, posebno zbog prisustva esencijalnih masnih kiselina, visokog sadržaja minerala, vitamina, lizina i skvalena. Skvalen, nezasićeni triterpenski ugljovodonik, često se koristi kao sastojak funkcionalne hrane, dodatak ishrani ili potencijalni lek. U poređenju sa ostalim tehnikama ekstrakcije ulja, ekstrakcija superkritičnim fluidima nudi brojne prednosti, kao što su netoksičnost rastvarača, očuvanje životne sredine i ekstrakcija na relativno niskim temperaturama. U radu je proučena kinetika superkritične ekstrakcije ulja iz tri sorte semena amaranta. Ekstrakcija ulja je izvedena pri procesnim uslovima: pritisak od 300 bara, temperatura 40°C i protok CO2 0,194 kg/h. U cilju proučavanja dinamike procesa ekstrakcije, vremenske sekvence ekstrakcije su postavljene na 30, 60, 90, 120, 150 i 180 min, s obzirom da je prinos dostigao ravnotežu nakon 3h za svaki od postupaka ekstrakcije. Prosečan sadržaj ulja u semenu amaranta iznosio je 58,2 g/kg, u rasponu od 54,6 do 61,1 g/kg u zavisnosti od sorte, dok se sadržaj skvalena kretao od 3,3 do 3,8 g/kg sa prosečnim sadržajem 3,5 g/kg. Glavni cilj rada je bio proučavanje kinetičkih aspekata superkritične ekstrakcije ulja modelovanjem krivih ekstrakcije. Za kinetičko modelovanje ekstrakcije uspešno je korišćeno pet empirijskih kinetičkih modela. Prema odgovarajućim statističkim karakteristikama (kao što su zbir kvadrata grešaka, koeficijent determinacije i prosečno apsolutno relativno odstupanje), empirijski modeli su pokazali dobro slaganje sa eksperimentalnim podacima. Matematičko modelovanje ekstrakcije ulja je značajno sa aspekta predviđanja odvijanja procesa, a takođe proširuje mogućnosti izvođenja postupka na industrijskom nivou.Amaranth seeds contain oil with important nutritional properties, in particular, because of the presence of essential fatty acids, high content of minerals, vitamins, lysine and squalene. In this study, the kinetics of the supercritical fluid extraction of oil from three amaranth seed varieties has been investigated. The average oil content in amaranth seed was 58.2 g/kg, ranging from 54.6 to 61.1 g/kg depends on varieties, while squalene content ranged from 3.3 to 3.8 g/kg with an average content of 3.5 g/kg dry seed. Five empirical kinetic equations were successfully applied for kinetic modeling of extraction. As indicated by the appropriate statistical "goodness of fit" tests (such as the sum of squared errors, the coefficient of determination and the average absolute relative deviation), empirical models show good agreement with experimental data. The mathematical modeling of a process is beneficial to predict the process conduct and furthermore extend the procedures from laboratory to industrial scales
Chemical Characterization of Marrubium vulgare Volatiles from Serbia
No full textMarrubium vulgare is a cosmopolitan medicinal plant from the Lamiaceae family, which produces structurally highly diverse groups of secondary metabolites. A total of 160 compounds were determined in the volatiles from Serbia during two investigated years (2019 and 2020). The main components were E-caryophyllene, followed by germacrene D, alpha-humulene and alpha-copaene. All these compounds are from sesquiterpene hydrocarbons class which was dominant in both investigated years. This variation in volatiles composition could be a consequence of weather conditions, as in the case of other aromatic plants. According to the unrooted cluster tree with 37 samples of Marrubium sp. volatiles from literature and average values from this study, it could be said that there are several chemotypes: E-caryophyllene, beta-bisabolene, alpha-pinene, beta-farnesene, E-caryophyllene + caryophyllene oxide chemotype, and diverse (unclassified) chemotypes. However, occurring polymorphism could be consequence of adaptation to grow in different environment, especially ecological conditions such as humidity, temperature and altitude, as well as hybridization strongly affected the chemotypes. In addition, this paper aimed to obtain validated models for prediction of retention indices (RIs) of compounds isolated from M. vulgare volatiles. A total of 160 experimentally obtained RIs of volatile compounds was used to build the prediction models. The coefficients of determination were 0.956 and 0.964, demonstrating that these models could be used for predicting RIs, due to low prediction error and high r(2)
Luminescent PMMA Films and PMMA"SiO2 Nanoparticles with Embedded Ln(3+) Complexes for Highly Sensitive Optical Thermometers in the Physiological Temperature Range**
No full textIn recent years, luminescent materials doped with Ln(3+) ions have attracted much attention for their application as optical thermometers based on both downshifting and upconversion processes. This study presents research done on the development of highly sensitive optical thermometers in the physiological temperature range based on poly(methyl methacrylate) (PMMA) films doped with two series of visible Ln(3+) complexes (Ln(3+)=Tb3+, Eu3+, and Sm3+) and SiO2 nanoparticles (NPs) coated with these PMMA films. The best performing PMMA film doped with Tb3+ and Eu3+ complexes was the PMMA[TbEuL(1)tppo]1 film (L-1=4,4,4-trifluoro-1-phenyl-1,3-butadionate; tppo=triphenylphosphine oxide), which showed good temperature sensing of S-r=4.21 % K-1 at 313 K, whereas for the PMMA films doped with Tb3+ and Sm3+ complexes the best performing was the PMMA[TbSmL(2)tppo]3 film (L-2=4,4,4-trifluoro-1-(4-chlorophenyl)-1,3-butadionate), with S-r=3.64 % K-1 at 313 K. Additionally, SiO2 NPs coated with the best performing films from each of the series of PMMA films (Tb-Eu and Tb-Sm) and their temperature-sensing properties were studied in water, showing excellent performance in the physiological temperature range (PMMA[TbEuL(1)tppo]1"SiO2: S-r=3.84 % degrees C at 20 degrees C; PMMA[TbSmL(2)tppo]3"SiO2: S-r=3.27 % degrees C at 20 degrees C) and the toxicity of these nanoparticles on human cells was studied, showing that they were nontoxic
Spatial and temporal distribution of pollution indices in marine surface sediments-a chemometric approach
No full textConcentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, and Fe measured at forty locations in the Boka Kotorska Bay were used to monitor the spatial and temporal quality of sediment and to assess surface sediment contamination over the last 15 years. This ecological geochemistry assessment was made using two classes of pollution indices: single indices concerning the investigated elements (contamination factor (Cf)) and integrated indices concerning the locations (pollution load index (PLI), potential ecological risk index (RI), mean effects range median quotient (MERMQ), toxic risk index (TRI), contamination severity index (CSI)). The distribution of all indices was geostatistically mapped and several hotspots were identified. Based on the indices applied in the risk assessment, the mean contribution of individual metal species to the total risk was determined and presented in the following order: Cd > Hg > As > Pb > Ni > Cu > Cr > Zn. This study revealed that Cd and Hg were at the top of the risk list among the examined elements. The temporal distribution of Hg has shown a decreasing trend during the period 2005-2019, while the presence of Cd in the Bay environment is of major concern. The results revealed that the most polluted part of the investigated area was Tivat bay within the Boka Kotorska Bay. Multivariate statistical analysis of pollution indices resulted in multicollinearity, which enabled the use of a reduced number of indices with an acceptable risk estimation
Comparative kinetic analysis of total hypericin extraction from Hypericum perforatum flowers carried out under simultaneous external physical field and cooling reaction system operational conditions
No full textThe comparative kinetic analysis of total hypericin (TH) extraction from the pre-extracted flowers of Hypericum perforatum carried out under simultaneous external physical field and cooling reaction system operational conditions (SEPFC) was performed. The kinetics curves of TH extraction in SEPFC were measured in the temperature range from T = 298 to 328 K. It was proved that presence of ultrasonic and microwave field cause increasing of the extraction rate compared to conventional isothermal extraction. The possibility of describing the kinetics of TH extraction in SEPFC with empirical (Elovich's model) and physically-based (film-theory model) were explored. The kinetic complexity of the process was examined with the differential isoconversional method. By applying the model-fitting method the proper kinetic model of TH extraction in SEPFC was found: [1- (1 - alpha)((1/3))](2) = k(M) . t. The values of the extraction rate constant (k(M)), activation energy (E-a) and pre-exponential factor (ln A) of TH extraction were calculated. The effect of ultrasonic and microwave field on (a) k(M); (b) E-a and (c) lnA of TH extraction was determined. The model mechanism of activation of hypericin molecule for extraction in SEPFC conditions was proposed. The values of wave number of resonant vibrations, vibration quantum number and anharmonicity parameter for the TH extraction are obtained
An Artificial Neural Network-based Prediction Model for Utilization of Coal Ash in Production of Fired Clay Bricks: A review
No full textThis study analyzed the last 20 years' data available on power plant coal ashes used in clay brick production. The statistical analysis has been carried out for a total of 302 cases based on the relevant parameters reported in the literature. The chemical composition of the clays and coal ashes, percentage incorporation and maximum particle size of ash, size of fired samples, peak firing temperature, and the corresponding soaking time were selected as inputs for modeling. The product characteristics i.e. open porosity, water absorption, and compressive strength was taken as output parameters. An artificial neural network model has been developed and showed a satisfactory fit to experimental data and predicted the observed output variables with the overall coefficient of determination (r(2)) of 0.972 during the training period. Besides, the reduced chi-square, mean bias error, root mean square error, and mean percentage error were utilized to check the correctness of the obtained model, which proved the network generalization capability. The sensitivity analysis of the model suggested that the quantity of Na2O coming from brick clays, the percentages of SiO2 and K2O coming from ashes, and MgO coming from clays were the most influential parameters in descending order for the ash-clay composite bricks' quality, mostly owing to the influence of fluxes during firing
Sugar beet molasses as osmotic solution for improving antioxidative potential of herbs
No full textNutritional and therapeutic relevance of herbs is generally known, which is most related to their high phenolic content and other bioactive compounds present. However, the bioactive components are unstable, and extremely prone to degradation and/ or reaction with some factors during processing and preservation. Osmotic treatment is the one of the preservation method with potential to prevent drying damages and maintain the functional properties of food. Most studies conducted with osmotic dehydration are more focused on the process, and less on the nutritive and antioxidative profile of obtained product. This review summarizes the impact of osmotic treatment on the antioxidative potential of osmodehydrated product, with an emphasis on the molasses as osmotic medium. Immersion of the plant material in concentrated solutions on the mild temperatures, by means of osmotic treatment, has the advantage of preserving the plants’ total antioxidant activity, due to the protective effect of the surrounding osmotic solution, the limitations of oxidative exposure, and avoiding adversely consequences of temperature. The type of osmotic solution directly affects the retention of bioactive compounds and the overall antioxidant profile of the material immersed in it, mainly due to the transport of bioactive substances from the solution to the plant. According to the literature molasses is a reach source of antioxidants, which potentially can diffuse into plant tissue during osmotic treatment. Some papers have reported that carriers of antioxidant activity in molasses are primarily phenolic compounds derived from sugar beet (Ferulic acid; Synergic acid; Vanilic acid; Galic acid; p-Coumaric acid; Kaempferol; Catechin; Luteolin), anthocyanides, betaine, choline, and colored products of the Millard reactions (melanoidins), which formed during the production of sugar. In conclusion the published data show that molasses as osmotic medium enhancing the overall antioxidant activity of herbs, making osmodehydrated material excellent ingredients for functional food formulation
Extractive desulfurization of pyrolysis tire oil with deep eutectic solvent using hydrodynamic cavitation
No full textThe extractive desulfurization (EXDS) of pyrolytic oil (PO) from organosulfur compound with deep eutectic solvent (DES), tetrabutylammonium bromide-formic acid, using hydrodynamic cavitation (HDC) was investigated. Applying the method of independent variation value one per variable, the effect of the processing parameters of EXDS using HDC: the inlet pressure of the reaction mixture (P-1), the mass ratio of DES to pyrolysis oil (DES/PO), the temperature of the reaction mixture (T) and the number of passes of the reaction mixture through the cavitation reactor (n), on the degree of desulfurization of pyrolytic oil (DDS) was determined. In order to determine the effect of processing parameters on the DDS, the processing parameters were varied following manners: (a) the value ofP(1)was varied in the range of 1-50 atm at DES/PO = 5,T= 298 K andn= 10, (b) the value of DES/PO was varied in the range of 1-10 atP(1)= 30 atm,T= 298 K andn= 10, (c) the value of temperatures was varied within the range 298-338 K atP(1)= 30 atm, DES/PO = 5, andn= 10, and (d) the value of (n) was varied within the range 1-20 atP(1)= 30 atm, DES/PO = 5, andT= 298 K. Based on the obtained results, it was found that the increase in the values ofP(1), DES/PO,T, andnleads to the increase in the value of DDS of pyrolytic oil. The optimal processing parameters EXDS of pyrolytic oil are determined. The model mechanism of the extractive desulfurization of pyrolytic oil with deep eutectic solvent and the influence of cavitation effects on the degree of pyrolytic oil desulfurization are discussed