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The aim of this paper is to determine the efficiency of D-µ-SPE with application of novel sorbents as a technique for sample preparation of water samples for the analysis of 16 priority PAHs by GC-MS. The sample preparation technique proved to be very fast, efficient and economical. The results of the proposed method demonstrate that this technique can be applied for routine analysis of PAHs in water. The advantages of this method are characterized by low values of limit of detection (from 0.147 ppb for benzo [a] anthracene to 0.784 ppb for naphthalene) and the limit of quantification (0.717 ppb for naphthalene to 9.459 ppb for benzo [k] fluorantene., Ciljevi istraživanja ovog rada su određivanje efikasnosti disperzivne mikroekstrakcije čvrstom fazom (D-µ-SPE) kao tehnike pripreme uzoraka vode za analizu 16 prioritetnih PAU gasnom hromatografijom sa masenom spektrometrijom, primenom novih sorbenasa. Tehnika pripreme uzoraka pokazala se kao veoma brza, efikasna i ekonomična. Rezultati predložene metode dokazuju da se ova tehnika može primeniti kao tehnika pripreme uzoraka za rutinsku analizu PAU u vodi. Prednosti ovakovog načina analize odlikuju se niskim vrednostima granice detekcije (od 0.147 ppb za benzo[a]antracen do 0.784 ppb za naftalen) i granice kvatifikacije (0.717 ppb za naftalen do 9.459 ppb za benzo[k]fluoranten).

The goal of this research was a comprehensive analysis of four wild edible mushroom species, Cantharellus cinereus, Clavariadelphus pistillaris, Clitocybe nebularis and Hygrocybe punicea, which have not been analyzed so far. Extracts of different polarities have been prepared and evaluated for their antioxidant activities by DPPH, ABTS, FRAP, TRP and CUPRAC methods. For all extracts, total phenolic content was determined. Based on the analysis, it was shown that solvent type had a significant effect on the antioxidant capacities of mushroom extracts, so water extracts showed the highest activity. Furthermore, the analysis includes determination of mineral composition, fatty acid profiles and antimicrobial activity. Unsaturated fatty acids, which are very important for human health, are dominant in the studied mushroom species. Linoleic and oleic acid consist of over 50 % of the total fatty acid composition. Seventeen biologically important and toxic elements have been analyzed by ICP-OES and ICP-MS and results showed that the element concentrations were species-dependent. Also, it has been found that analyzed mushrooms did not show any antimicrobial activity. Chemometric analysis was used to understand the connection between the extracts of different polarities.

Polycyclic aromatic hydrocarbons (PAH) are pollutants of great concern due to their toxicity. European Commission classified 16 compounds as priority pollutants based on their toxicity, carcinogen potential and occurrence. PAH analysis in soil is of great importance, but due to PAHs low concentrations and low selectivity of organic solvents is challenge. The aim of this dissertation was to optimize extraction (ultrasound, Soxhlet extraction and QuEChERS) and clean up techniques for the extraction of 16 priority PAHs from soil, followed by GC - MS analysis. The best results were obtained by QuEChERS technique using acetonitrile/water (1:2, v/v) as extraction solvent and diatomaceous earth as clean up sorbent. Recovery values varied between 81% for benzo[b]fluoranthene to 109% for benzo[a]pyrene. Proposed QuEChERS technique is accurate and precise, but also cheaper and simpler than other methods used for PAH extraction from soil. Optimized QuEChERS technique was applied for real soil samples analysis from urban area of Niš. The content of total PAHs varied from 0,346 48,678 mg kg-1. Multivariate statistical analysis enabled grouping of soil samples based on PAH and heavy metal concentrations and soil properties.

Тhe chemical composition of essential oils, extracts of different polarity, and mineral composition of plants Seseli rigidum and Seseli pallasii were analysed. For rapid analysis of volatiles of S. rigidum above ground parts, and S. pallasii fruits and roots volatiles, HS/GCMS technique may be used, while in all other cases is necessary to isolate essential oils and apply GC-MS technique. According to principle component analysis (PCA) and hierarchical cluster analysis (HCA) a groupings of the samples were done, based on the similarity of the chemical composition of certain plant parts (leaf, flower, fruit and roots). The variables based on the dominant components were grouped using PCA and HCA analysis. Biological activities and characteristics of essential oils, extracts of different polarity of vegetative parts of both plants were investigated. Antioxidant properties were tested using ABTS, DPPH, total reducing power methods, total flavonoids and total phenols content. According to the ABTS and DPPH methods, the best properties were manifested by hexane extracts of both tested plant species, and flower acetone extract of S. rigidum, respectively, while the highest total reducing capacity had the methanol extracts of S. rigidum. The highest total phenols and flavonoids were registered for hexane extracts of root and leaf of S. pallasii. Both applied methods of statistical analyses (PCA and HCA) in which the results of antioxidant activities were used as variables, clearly distinguished DPPH method from other methods, and tested samples were separated by type (oils and extracts), and according to the type of solvent used in the preparation of extracts. Determination of antimicrobial activity of essential oils and extracts versus different strains of Gram (+) and Gram (-) bacteria, using the microdilution method, showed that the root essential oil of S. rigidum had the most pronounced effect. In terms of inhibition of enzyme cholinesterase, estimated using Elman’s m

This paper reports for the first time the effect of an acetone extract of Umbilicaria crustulosa on the micronucleus distribution of human lymphocytes, and on the cholinesterase activity and antioxidant activity by the cupric ion reducing antioxidant capacity (CUPRAC) method. Additionally, the total phenolic compounds (TPC) and the antioxidant properties were estimated via DPPH, ABTS and TRP assays. Moreover, the antibacterial activity against two Gram-positive and three Gram-negative bacteria were determined. Acetone extract of U. crustulosa at concentration of 1 and 2 mu g mL(-1) decreased a frequency of micronuclei (MN) by 10.8 and 16.8 %, respectively, acting more or slightly less than the synthetic protector amifostine (AMF, WR-2721, 11.4 %, at concentration of 1 mu g mL(-1)). The tested extract did not inhibit cholinesterase activity nor did it exhibit activity toward the examined bacteria. The extract reduced the concentration of DPPH and ABTS radicals by 88.7 and 96.2 %, respectively. Values for total reducing power (TRP) and cupric reducing capacity (CUPRAC) were 0.6197+/-0.0166 mu g ascorbic acid equivalents (AAE) per mg of dry extract, and 19.7641+/-1.6546 mu g trolox equivalents (TE) per mg of dry extract, respectively. The total phenol content was 350.4188 +/-14.587 mu g gallic acid equivalents (GAE) per mg of dry extract. The results of the present study showed that U. crustulosa acetone extract is a promising candidate for in vivo experiments considering its antioxidant activity and protective effect on human lymphocytes.

In order to determine the terpenes effect on enzyme activity is been studied the impact of aqueous (prepared manually (I1) or ultrasound (I2) mixing) and DMSO (dimethyl sulfoxide) terpenes solution (carvacrol, linalool, nerol and geraniol) on the activity of creatine kinase, lactate dehydrogenase, alkaline phosphatase, gamma-glutamyl transferase, aspartate aminotransferase and alanine aminotransferase,as well as the impact of the same type of terpenes solution (carvacrol, linalool, nerol, geraniol, β-pinene, myrcene, citral, eucalyptol, terpineol, and eugenol) on the activity of amylase in the control sera (with the normal (N) and increased (H) activity of the ingredients. Measurement of activity was conducted after incubation of the serum sample from the 10 minutes and aqueous solutions of terpenes prepared as I1 or as I2, or solutions of terpenes in DMSO at four concentrations. All the terpenes solutions have demonstrated that the inhibitory effect depends on various parameters: kinds of serum (higher percentage of inhibition in N than the H serum), the type of solvent ( the aqueous solution as I2 and DMSO solutions showed approximately the same percentage of inhibition in both types of serum) and way of preparing the aqueous solutions (a higher percentage of inhibition have the aqueous solution of terpenes as I2 in N serum and as I1 in H serum), as well as on the type of terpenes or enzymes. Statistical data processing all terpenes solution (with the partial exception of neroli and geraniol) confirmed the grouping or by type of serum or by type of solvent or the method of preparation of aqueous solution.

Poslednjih decenija jedan od vodećih problema u medicini je stvaranje rezistentnosti patogenih mikroorganizama na delovanje antibiotika. Bakterije koje pokazuju značajnu rezistentnost na postojeće antibiotike su: meticilin rezistentni Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Acinetobacter spp., itd. Prilikom delovanja na patogene bakterije, antibiotici neselektivno utiču i na nepatogene bakterije, izazivajući pri tom nepredvidive genetske promene. Pored korisnih efekata u delovanju na bakterije, raspoloživi antibiotici, takođe mogu prouzrokovati neželjene efekte kao što su hipersenzitivnost i imunosupresija. To je razlog zbog koga se traga za novim agensima sa antibiotskim delovanjem. Jedan od prirodnih izvora takvih agenasa su etarska ulja i ekstrakti aromatičnih biljaka koji se koriste u tradicionalnoj medicini za lečenje mnogih infektivnih bolesti i bolesti koje nastaju kao posledica oksidativnog stresa. Zbog toga je cilj istraživanja ove disertacije bio da se izvrši komparativna analiza hemijskog sastava, antibakterijske i antioksidativne aktivnosti odabranih biljnih vrstaAngelica pancicii, Angelica sylvestris, Laserpitium latifolium, Achillea grandifolia, Achillea crithmifolia, Artemisia absinthium, Tanacetum parthenium i Hyssopus officinalis koje su veoma zastupljene u tradicionalnoj medicini. Materijal i metode. Biljni materijal koji je korišćen u ovom istraživanju je prikupljan tokom 2012. i 2013. godine na teritoriji jugoistočne Srbije. Nakon sušenja biljnog materijala, pristupilo se procesu izolovanja etarskih ulja metodom hidrodestilacije u aparaturi po Klevindžeru, kao i pripremanju metanolnih ekstrakata alkoholnom ekstrakcijom. Hemijski sastav ulja je analiziran pomoću GH (gasna hromatografija) i GH/MS (gasna hromatografija sa spektrometrijom masa) metoda. Ukupni fenoli su određivani metodom po Folin-Sjoklto-u, sa malim modifikacijama, a ukupni flavonoidi su utvrđivani korišćenjem aluminijum hlorid (AlCl3) kolorimetrijskog metoda. Antioksid, During the last several decades one of the leading challenges in medicine is appearance of resistance of pathogenic microorganisms to antibiotic activity. Bacteria showing significant resistance on existing antibiotics include: methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Acinetobacter spp., etc. During the activity on pathogenic bacteria, the antibiotics simultaneously show non-selective impact on nonpathogenic bacteria, causing unpredictable genetic changes. In addition to beneficial effects on bacteria, the available antibiotics may also cause adverse effects such as hypersensitivity and immunosuppression. Therefore studies of new agents with antibiotic activity are constantly ongoing. One of the natural sources of such agents are essential oils and extracts of aromatic plants used in traditional medicine as a cure for many infectious diseases and ailments caused by oxidative stress. Therefore the goal of study presented in this dissertation was comparative analysis of chemical composition, antibacterial and antioxidant activity of eight chosen plant species regularly represented in traditional medicine: Angelica pancicii, Angelica sylvestris, Laserpitium latifolium, Achillea grandifolia, Achillea crithmifolia, Artemisia absinthium, Tanacetum parthenium and Hyssopus officinalis. The plant material used in this study was collected in 2012 and 2013 in southeastern Serbia. After the plant material was dried, essential oils were isolated by hydro-distillation method using the Clevenger apparatus, while methanol extracts were prepared by alcoholic extraction. The chemical composition of oil was analyzed by GC (gas chromatography) and GC/MS (gas chromatography with mass spectrometry) methods. The total amount of phenols was determined by Folin-Ciocalteu method with slight modifications, while total flavonoids were determined by aluminum chloride (AlCl3) colorimetric method. The antioxidant activity of essential oils and extracts was deter

The aim of this study was to determine and evaluate the amounts of major elements (Ca, Fe, K, Na and P), essential trace elements (Cu, Zn, Fe and Mn) and some other trace metals (Ag, Al, Co, Ni, Cr, Sr, Se, Bi, Rb) in eleven species of wild-grown common edible mushrooms from family Boletaceae (Boletus appendiculatus, Boletus edulis, Boletus regius, Boletus fechtneri, Boletus impolitus, Boletus purpureus, Boletus rhodoxanthus, Leccinum crocipodium, Leccinum pseudoscaber, Xerocomellus chrysenteron, Xerocomus badius) from Serbia. The measurements of major elements (Ca, Fe, K, Na and P) were carried out by inductively coupled plasma optical emission spectrometer (ICP-OES), while analytical measurements of the rest of studied elements were performed using an inductively coupled plasma mass spectrometer (ICP-MS), after microwave digestion. The results showed that the element concentrations were species-dependent. Potassium and phosphorous concentrations were found to be greater than those of the other mineral constituents in all tested species. Multivariate analysis included principal component analysis (PCA) and hierarchical cluster analyses (HCA). HCA grouped mushrooms in three statistically significant clusters, while PCA indicated connection between analyzed metals. Also, this paper highlights the importance of essential and nonessential elements of human health and their daily intake.

aromatičnih biljaka koje se koriste u tradicionalnoj medicini, hortikulturi, hemijskoj, prehrambenoj i kozmetičkoj industriji. Retke, endemične i/ili ugrožene vrste familije Lamiaceae predstavljaju poseban izazov za proučavanje, prevashodno u cilju očuvanja specijskog diverziteta i njihovih populacija u prirodi, ali i zato što su izvor važnih bioaktivnih molekula raznovrsnog dejstva (antimikrobna, antvirusna, fungicidna, antioksidantna, citotoksična, alelohemijska, insekticidna aktivnost, itd.) i potencijalno široke primene. Usled izrazite heterogenosti, predstavnici roda Micromeria su bili često predmet taksonomskih diskusija. Pripadnike sekcije Pseudomelissa gde spada i М. pulegium, nakon molekularno genetičkih analiza hloroplastne DNK, Brauchler (2005) premešta u rod Clinopodium. Ipak, u ovoj tezi je primenjen tradicionalni taksonomski koncept, predložen od strane Harley-a i sar. (2004), koji podržava homogenost roda Micromeria, pri čemu je sect. Pseudomelissa njegova sastavna jedinica. U skladu sa primenjenim sistemom dve istraživane vrste su klasifikovane u idividualne sekcije roda: Micromeria sect. Micromeria (M. croatica), odnosno Micromeria sect. Pseudomelissa (M. pulegium). Micromeria pulegium predstavlja endemičnu vrstu Južnih Karpata u Rumuniji, sa enklavom u istočnoj Srbiji, a Micromeria croatica balkansku endemičnu vrstu čiji se areal vezuje pre svega za planinski venac Dinarida. Njihove prirodne populacije imaju mali broj jedinki i nastanjuju staništa koja su pod negativnim uticajem antropogenih faktora. Imajući u vidu značaj roda Micromeria, kao i činjenicu da su pomenute vrste retke i ugrožene, javila se potreba da se one gaje zarad očuvanja i istraživanja bez pritiska na prirodne populacije i bez remećenja prirodnog genofonda. Iz pomenutih razloga obe vrste roda Micromeria uvedene su kulturu biljnih tkiva in vitro. U ovoj disertaciji vršeno je ispitivanje efekata regulatora rastenja na morfogenezu i produkciju etarskih ulja endemičnih vrsta M. puleg, Plants from Lamiaceae family are prominent representatives of the edible, medicinal or aromatic herbs used in traditional medicine, horticulture, chemical, cosmetic and food industry. The rare, endemic and/or threatened species from family Lamiaceae pose a special challenge for studying, primarily in order to preserve species diversity and their populations in the wild, but also as they are source material for important bioactive molecules with diverse activity (antimicrobial, antiviral, fungicidal, antioxidant, cytotoxic, allelochemical, insecticidal and other types of activity) and potential broad spectrum of use. Due to the pronounced heterogeneity, representatives of genus Micromeria used to be a common topic of taxonomic discussions. After the molecular-genetic analyses of chloroplast DNA, Brauchler (2005) has transferred the representatives of section Pseudomelissa, which includes М. pulegium, into the genus Clinopodium. However, this thesis is using the traditional taxonomic concept suggested by Harley et al. (2004), supporting the homogeneity of genus Micromeria, where sect. Pseudomelissa remains its integral unit. According to this system the two studied species were classified within the individual sections of the genus: Micromeria sect. Micromeria (M. croatica) and Micromeria sect. Pseudomelissa (M. pulegium). Micromeria pulegium represents an endemic species of Southern Carpathians in Romania, with an enclave in Eastern Serbia, while Micromeria croatica is an endemic Balkan species primarily connected with the mountain chain of Dinarides. Their natural populations are characterized by a small number of individuals inhabiting habitats under the negative influence of anthropogenic factors. Due to the importance of genus Micromeria and the fact that these two species are rare and threatened, a need arose to grow them in captivity so they may be preserved and studied without additional pressure on natural populations and without disturbance of the natural ge

Plants synthesize primary and secondary metabolites from simple molecules, among wich inorganic compounds are of great importance. Examining the extractability and solubility of the soil elements helps us explicate the mechanism of their adsorption by plants. Besides primary and secondary metabolites, witch were proven to have healing properties, plants are a source of necessary elements wich are on a biochemical level important for optimal functioning of the human body. Taking into regard the bacterial resistance towards synthetic antibiotics, in the past few decades, it is necessary to systematically search for new antibacterial agents, and essential oils are potentially the most abundant reservoir of natural antibiotics. The development of new methods based on a combined interaction of synthetic and natural antibiotics can help us solve the issue of bacterial resistance. A number of scientific researches, wich have been conducted in the past few years, have focused on analyzing the experimental results using chemometric methods. Depending on the angle from witch the problem is approached; i.e. depending on the chosen variables, the chemometric method and the interpretation of correlations can be applied to experimental system, in order to determine its connections, similarities and differences. Recently, chemometric methods have started being used for ecosystem analysis, in order to determine the distribution and accumulation of specific minerals in the soil and plants. The dependance of chemical structures in natural and syntethic antibiotics and their pharmacological activities has also been a subject of intensive research.

Cilj ovog rada je praćenje sukcesije na požarištima krečnjačkog terena planine Vidlič u jugoistočnoj Srbiji nakon požara 2007. godine koji je zahvatio ogromnu površinu planine. Na osnovu višegodišnjeg terenskog istraživanja oformljena je obimna herbarska zbirka kao i velika količina florističkih, fitocenoloških i ekoloških informacija uobličenih u vidu baze podataka, koji govore o flori i vegetaciji na pomenutom području. Sistematskim terenskim istraživanjem utvrđeno je da floru planine Vidlič izgrađuje 1265 taksona u rangu vrste i podvrste. Sakupljeno je 10985 herbarskih uzoraka sa terena planinskog venca Via, što predstavlja zbir prikupljenih herbarskih i literaturnih podataka. Radi lakše analize zabeleženih podataka, koji se odnose na opožarene i neopožarene površine,uvedene su tri skraćenice: Po, NP i CP. Skraćenicom Po (“požarište”) označene su sve opožarene površine, uključujući požarišta u zoni bukovih šuma, požarišta u zoni hrastovih šuma I požarište otvorenih staništa odnosno suvih pašnjaka i kamenjara. Skraćenicom NP (“neopožarene površine”), označene su sve neopožarene površine, koje se nalaze u neposrednoj okolini požarišta odnosno svih opožarenih površina. Skraćenicom CP

Propranolol, a widely used beta-blocker, inhibits the hydrolysis reaction of enzyme cholinesterase. Measurements of the difference in rate of hydrolysis rate between uninhibited and inhibited reactions allow the development of a kinetic method for its determination. Both systems, enzyme-substrate-chromogen and enzyme-substrate-chromogen-inhibitor, were characterized through biochemical kinetic parameters (K-M, 0.326-0.330 mmol/L; V-max, 40.0-43.0 mu mol/Lmin). The inhibition type was recognized as competitive and the inhibition constant, Ki, was determined to be 22.60 mu mol/L. The detection and quantification limits were calculated as 0.004 and 0.0136 mu mol/L, respectively. Accuracy and precision of proposed methods were tested. The proposed method showed good sensitivity, selectivity, simplicity and rapidity, thus it is convenient for clinical applications., Za propranolol, često propisivani neselektivni beta blokator, utvrđeno je da inhibira reakciju enzimske hidrolize butiriltioholin-jodida, koja je katalizovana serumskom holinesterazom. Merenjem razlike u brzini osnovne i inhibitorske reakcije hidrolize u prisustvu propranolola kao inhibitora, moguće je razviti kinetičku metodu za određivanje propranolola. Oba sistema, enzim-supstrat-hromogen kao i enzim-supstrat-hromogen-inhibitor, okarakterisani su biohemijskim kinetičkim parametrima (KM, 0,326-0,330 mmol/L; Vmax, 40-42,99 μmol/L min), inhibicija je definisana kao kompetitivna i određena je konstanta inhibicije 22,60 μmol/L. Da bi se u potpunosti iskoristile sve mogućnosti predložene metode u pogledu osetljivosti, tačnosti, preciznosti i selektivnosti, optimizovani su reakcioni uslovi. Konstruisana je kalibraciona prava, izračunata odgovarajuća jednačina i određeni granica detekcije i kvantifikacije i to 0,004 i 0,0136 μmol/L, redom. Tačnost i preciznost predložene metode su ispitane za tri koncentracije propranolola u oblasti kalibracione prave (0,082-21,120 μmol/L) u pet ponavljanja. Takođe, ispitan je uticaj većeg broja supstanci koje se mogu naći u uzorku na brzinu reakcije. Optimizovana metoda je primenjena za određivanje propranolola u farmaceutskim preparatima. Tačnost predložene metode je ispitana primenom metode standardnog dodatka. Predložena metoda ima dobru osetljivost, selektivnost, jednostavna je i brza, i nadasve lako dostupna, i na taj način primenljiva u velikom broju laboratorija.

A modification of the existing spectrophotometric kinetic method for the determination of pancuronium bromide (PCBr), based on pooled human serum cholinesterase (ChE, EC 3.1.1.8 acylcholine acylhydrolase) inhibition, was developed. Butyrylthiocholine iodide (concentration 1.667 mmol/L) was used as substrate and determination was performed at pH 7.6. Essential basic kinetic parameters were also determined: Michaelis-Menten's constant K-M=0.33 mmol/L, maximal reaction rate V-max=42.29 mu mol/ L min, inhibition constant K-I = 0.34 mu mol/L, and IC50=0.235 mu mol/L. Linear dependence between the reaction rate and the inhibitor concentration exists in PCBr concentration range 8.29-265.28 nmol/L, which corresponds to the real sample concentrations from 0.166 to 5.306 mu mol/L. The method detection limit was established to be 1.86 nmol/L and the quantification limit was 6.18 nmol/L. Precision of the method was tested for three pancuronium concentrations (16.58, 99.48, and 198.96 nmol/L). The relative standard deviation (RSD) was in the range 0.78-5.13%. Accuracy was examined by the standard addition method. The influence of substances usually present in serum and urine on the reaction rate was determined. The method developed was applied for PCBr determination in spiked serum and urine samples and in the urine taken during surgery. The method was proven to have good sensitivity, accuracy, and precision and can be considered suitable for clinical practice.