The correlation of metal content in medicinal plants and their water extracts

The quality of some medicinal plants and their water extracts from South East Serbia is determined on the basis of metal content using atomic absorption spectrometry. The two methods were used for the preparation of water extracts, to examine the impact of the preparation on the content of metals in them. Content of investigated metals in both water extracts is markedly lower then in medicinal plants, but were higher in water extract prepared by method (I), with exception of lead content. The coefficients of extraction for the observed metal can be represented in the following order: Zn > Mn > Pb > Cu > Fe. Correlation coefficients between the metal concentration in the extract and total metal content in plant material vary in the range from 0.6369 to 0.9956. This indicates need the plants to be collected and grown in the unpolluted area and to examine the metal content. The content of heavy metals in the investigated medicinal plants and their water extracts is below the maximum allowable values, so they are safe to use

A Proposed Method for Determining Propulsion Coefficient Based on Testing Motor Freighters on Danube Waterway Network

The paper presents a proposal of mathematical models for the determination of propulsion coefficient, eta pp, intended for the analysis of motor freighters applied on the river watercourses. As the main paper contribution three different model types are developed, depending on the variable which contributes to eta pp value. These variables are: 1. the freighter sailing velocity, (nu); 2. the installed capacity of the main drive motor of outboard unit, (N-inst); 3. the combination of these two variables, (N-inst, nu). The models are verified on the examples of several motor freighters which are applied at Danube river. The special attention is paid to the determination of the optimum approximation function in each case. In all three cases it is a quadratic function. The correlation coefficient for the comparison in all analyzed examples is higher than 0.87, being even higher than 0.99 for the first model

A Proposed Method for Determining Propulsion Coefficient Based on Testing Motor Freighters on Danube Waterway Network

The paper presents a proposal of mathematical models for the determination of propulsion coefficient, eta pp, intended for the analysis of motor freighters applied on the river watercourses. As the main paper contribution three different model types are developed, depending on the variable which contributes to eta pp value. These variables are: 1. the freighter sailing velocity, (nu); 2. the installed capacity of the main drive motor of outboard unit, (N-inst); 3. the combination of these two variables, (N-inst, nu). The models are verified on the examples of several motor freighters which are applied at Danube river. The special attention is paid to the determination of the optimum approximation function in each case. In all three cases it is a quadratic function. The correlation coefficient for the comparison in all analyzed examples is higher than 0.87, being even higher than 0.99 for the first model

Multielement determination using inductively coupled plasma optical emission spectrometry for metal characterization of water from artesian wells in Semberija region: Multivariate analysis of data

The concentrations of fifteen metals (Mg, Na, Ca, K, Se, Zn, Mn, Fe, Pb, Cr, Cu, Cd, Sb, Ni, Co) were determined in water from ten artesian wells (AW) in Semberija to obtain a general metal profile of water in this region. Principal components analysis (PCA) was used in this classification. Using principal component analysis two factors controlling the metal variability were obtained, which accounted for nearly 71.5% of the total variance. Natural (lithogenic) factor is represented by PC1, while anthropogenic factor is represented by PC2. PC1 with high contribution of Mn, Mg, Na, K, Ca, Zn and Se accounting for 41.84% of the total variance, while PC2 exhibits high loading for Cd, Ni, Sb, Cr and Pb (29.66%). Three general areas (clusters) with different metal characteristics were detected. Water from artesian wells in first cluster (AW1, AW2, AW3, AW4, AW5 and AW6) had much higher metal concentration compared with those in the second (AW7, AW8 and AW9) and third cluster (AW10). That is as a result of anthropogenic inputs. Also, the analysis of water demonstrated slightly elevated values for Mn (concentrations up to 0.176 mg/L), while concentrations of the other investigated elements are below the values recommended by the World Health Organization (WHO) and the United States Environmental Protection Agency (US EPA). [Projekat Ministarstva nauke Republike Srbije, br. 172047

EFFECT OF STORAGE TEMPERATURE AND THERMAL PROCESSING ON CATECHINS, PROCYANIDINS AND TOTAL FLAVONOIDS STABILITY IN COMMERCIALLY AVAILABLE COCOA POWDERS

Storage stability of catechin, epicatechin, procyanidins B1-B4 and total flavonoids in cocoa powder samples was studied over the temperature range 4-35 ºC. Thermal stability of total flavonoids was studied over the temperature range 95-125 ºC. Total flavonoids concentration decreased as a function of time and the degradation was accelerated at higher temperatures: a half-life (t1/2) of total flavonoids was much shorter at room temperature than during cold storage. A first-order kinetic model fitted well to all the data. Temperature dependence of the degradation rate constants, described by the Arrhenius equation, was more pronounced during heating than during storage. In the temperature interval from 4 ºC to 35 ºC, the calculated activation energies (Ea) for catechin, epicatechin and procyanidins B1-B4 were 20.4 kJ/mol, 12.5 kJ/mol, 9.4 kJ/mol, 21.6 kJ/mol, 19.4 kJ/mol, 23.7 kJ/mol, respectively. UTICAJ TEMPERTURE ČUVANJA I ZAGREVANJA NA SADRŽAJ KATEHINA; PROCIJANIDINA I UKUPNIH FENOLA KOMERCIJALNIM UZORCIMA KAKAOA U PRAHUUticaj temperature čuvanja na stabilnost katehina, epikatehina, procijanidina B1-B4 i ukupnih flavonoida u uzorcima kakaoa u prahu praćen je u temperaturnom opsegu od 4 ºC do 35 ºC. Uticaj zagrevanja na sadržaj ukupnih flavonoida je praćen u temperaturnom opsegu od 95 ºC do 125 ºC. U toku skladištenja uzoraka je došlo do smanjenja u sadržaju ukupnih flavonoida. Pomenuta promena je bila izraženija na višim temperaturama: vreme polu-života (t1/2) ukupnih flavonoida u ispitivanom uzorku kakaoa u prahu bilo je kraće kada je on čuvan na sobnoj temperaturi nego kada je čuvan u frižideru. Promene u sadržaju flavonoida u ispitivanim uzorcima prate kinetiku prvog reda. Konstante brzine degradacije, izračunate pomoću Arenijusove jednačine, veće su tokom zagrevanja nego tokom čuvanja ispitivanih uzoraka na nižim temperaturama. Izračunate energije aktivacije (Ea) za katehin, epikatehin i procijanidine B1, B2, B3 i B4 u temperaturnom intevalu od 4 ºC do 35 ºC  bile su: 20,4 kJ/mol, 12,5 kJ/mol, 9,4 kJ/mol, 21,6 kJ/mol, 19,4 kJ/mol i 23,7 kJ/mol. HIGHLIGHTS Storage stability of (epi)catechin, procyanidins B1-B4 and total flavonoids in cocoa powder samples was studied(temperature range 4-35 °C)The stability of the total flavonoids was studied over the temperature range 95-125 °CThe degradation of the total flavonoids was significantly accelerated at higher temperaturesTemperature dependence of the degradation rate constants was more pronounced during heating than during storag

TOTAL PHENOL, FLAVONOID AND HEAVY METAL CONTENT AND ANTIOXIDANT ACTIVITY OF SOLVENT EXTRACTS OF ORIGANUM VULGARE L.

Water, ethanol and water-ethanol (1:1, v/v) extractsofthe (ethno)pharmacologically valued plant species Origanum vulgare L. were studied for the total phenol (TP), flavonoid (TF) and heavy metal (HM; Zn, Fe, Cu, and Mn) content. All three prepared extracts contained a rather high amount of phenolics (23.6-75.2 mg gallic acid equivalents/g) and a low amount of flavonoid compounds (1.0-2.1 mg quercetin equivalents/g). In addition, the content of (toxic) metals (Zn, Fe, Cu, and Mn) was low (0.4-153 mg/kg). Antioxidant potential of the extracts was determined using a DPPH assay and correlated with TP, TF and HM. According to the obtained results, the high observed radical scavenging activity (75.1-93.8%) is mostly related to the presence of flavonoid and other phenolic compounds. SADRŽAJ UKUPNIH FENOLA, FLAVONOIDA I TEŠKIH METALA, KAO I ANTIOKISIDATIVNA AKTIVNOST EKSTRAKATA BILJNE VRSTE ORIGANUM VULGARE L. U ovom radu su izloženi rezultati ispitivanja sadržaja ukupnih fenola (TP), flavonoida (TF) i teških metala (HM; Zn, Fe, Cu i Mn) u vodenom, etanolnom i vodeno-etanolnom (1:1, v/v) ekstraktu (etno)farmakološki cenjene biljne vrste Origanum vulgare L. U svim ispitivanim ekstraktima  je utvrđeno prisustvo relativno visoke koncentracije fenolnih jedinjenja (23,6-75,2 mg ekvivalenata galne kiseline/g) i niske koncentracije flavonoida (1,0-2,1 mg ekvivalenata kvercetina/g). Pored toga, sadržaj (toksičnih) metala (Zn, Fe, Cu i Mn) je bio relativno nizak (0,4-153 mg/kg). Antioksidativni potencijal ispitivanih ekstrakata je određen DPPH metodom i korelisan sa TP, TF i HM. Na osnovu dobijenih rezultata, jaka antioksidativna aktivnost (75,1-93,8%) ekstrakata je uglavnom posledica prisustva flavonoida i drugih fenolnih jedinjenja

Biochemical and ultrastructural changes in the liver of European perch (Perca fluviatilis L.) in response to cyanobacterial bloom in the Gruža reservoir

We investigated the biochemical and ultrastructural changes in the liver of the freshwater fish, European perch (Perca fluviatilis), in response to Aphanizomenon flos-aquae bloom in the Gruža Reservoir, Serbia. The activities of total manganese- and copper zinc-containing superoxide dismutase (Tot SOD, Mn-SOD, Cu/Zn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and biotransformation phase II enzyme glutathione-S-transferase (GST), as well as concentrations of total glutathione (GSH) and sulfhydryl (-SH) groups were examined before and during the bloom period. Mn-SOD activity was significantly higher, while the activities of Cu/Zn-SOD, CAT and GSH-Px and the concentration of the -SH groups were significantly lower during the bloom. The ultrastructure of the liver revealed necrotic and apoptotic damage to the hepatocytes during the bloom period. Our work represents the first study to report the influences of an Aphanizomenon flos-aquae bloom in the Gruža Reservoir on antioxidant biomarkers and on histopathological alterations in the liver of the freshwater fish European perch (Perca fluviatilis)

Relationships among some pines from subgenera pinus and strobus revealed by nuclear est-microsatellites

Genetic relationships among 12 taxa from subgenera Pinus and Strobus were studied through fourteen microsatellite markers, previously developed for Pinus taeda. To our knowledge, this is the first comparative study of pines using nuclear EST-microsatellites (EST-SSRs). The total number of detected alleles in all investigated taxa was 72 (5.14 in average). The numbers of alleles per locus and PIC values for estimated markers ranged from 3 to 7, and from 0.43 to 0.81, respectively. Presented results are in accordance with majority of previous genetic investigations and infrageneric classification of genus Pinus up to the sectional level, while subsectional position of some species has still not dismissed, especially regarding relict ones. According to nuclear EST-SSRs, Pinus heldreichii is in early-diverging position within subsection Pinaster and shows the greatest closeness with P. halepensis, while Pinus peuce doesn't have basal position within subsection Strobus being more close to P. strobus than to P. wallichiana. Furthermore, the closest connections in subsection Pinus were found between two Pinus nigra subspecies (dalmatica and nigra) as well as between P. sylvestris and P. mugo

Određivanje antioksidativnog kapaciteta uzoraka kakao praha, crne i mliječne čokolade pomoću cikličke voltametrije: korelacija s rezultatima spektrofotometrijskog ispitivanja i udjelima pojedinačnih fenolnih spojeva

Phenolic antioxidants in cocoa powder, dark chocolate and milk chocolate samples are quantified electrochemically using cyclic voltammetry with a glassy carbon electrode. Cyclic voltammograms were recorded from 0 to 800 mV at a scan rate of 100 mV/s. Phenolics with an ortho-diphenol group show the first oxidation peak in the potential range between 370 and 460 mV (vs. Ag/AgCl) in 0.1 mol/L of the acetate buffer, pH=4. The first and third anodic current peaks, close to 670 mV, can be ascribed to the first and second oxidation of the catechin-type flavonoids that are present at a high concentration in samples. The second peak at around 560 mV can be ascribed to phenolic acids. Procyanidins B1, B2, B3 and B4 did not have any visible waves. Strong positive correlation was established between antioxidant activities deduced from cyclic voltammograms with those determined using spectrophotometric assays. HPLC method was used for the quantification of individual phenolic compounds.Fenolni su antioksidansi u uzorcima kakao praha, tamne i mliječne čokolade elektrokemijski određeni pomoću cikličke voltametrije, primjenom elektrode od staklastog ugljika. Ciklički su voltamogrami snimljeni u rasponu od 0 do 800 mV, pri brzini skeniranja od 100 mV/s. Fenolni su spojevi s orto-difenilnom grupom dali prvi oksidacijski pik pri potencijalu između 370 i 460 mV (u usporedbi s referentnom elektrodom Ag/AgCl) u acetatnom puferu koncentracije od 0,1 mol/L, pH=4. Prvi i treći anodni pikovi, dobiveni pri otprilike 670 mV, potječu od prve i druge oksidacije katehina, prisutnih u većim udjelima u ispitivanim uzorcima. Drugi pik, dobiven pri otprilike 560 mV, potječe od fenolnih kiselina. Procijanidini B1, B2, B3 i B4 nisu dali vidljive pikove. Utvrđena je jaka pozitivna korelacija između antioksidativne aktivnosti određene cikličkom voltametrijom i one određene spektrofotometrijom. Za određivanje udjela pojedinačnih fenolnih spojeva upotrijebljena je metoda HPLC

Levels of Major and Minor Elements in Some Commercial Fruit Juices Available in Serbia

Purpose: To evaluate the macro- and micro-nutrient elements of some commercially available fruit juices in Serbia. Methods: Inductively coupled plasma optical emission spectrometry (ICP-OES) technique was employed for determination of the major and minor elements in samples of two different types of fruit juices - clear and cloudy. Results: Among macro-nutrient elements, potassium (K) had the highest content of 230.17 µg/g in samples of multivitamine cloudy juice. The content of K was higher in cloudy fruit juices than in clear fruit juices. The content of iron, which is among the group of trace elements, ranged from 2.237 to 5.911 µg/g in clear juices and 3.55 to 10.05 µg/g in cloudy fruit juices. Other trace elements followed the descending order copper > zinc > nickel in terms of their content. The presence of aluminum and cadmium in the tested samples of fruit juices can be toxic since they have no nutritional value, and hence may be treated as potential contaminants in these beverages. Conclusion: All the tested juices had some nutritional value for human health and the juices could be use as an additional source of these elements. The content of aluminium and cadmium are below levels permitted by national regulations