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Polyphenols are ubiquitous natural compounds that show chemopreventive, cytostatic, immunomodulatory, bacteriostatic/bactericidal, antifungal, anti-inflammatory, antioxidant and many other pharmacological activities. Propolis, wine and many medicinal plants used in everyday life as functional food present rich sources of polyphenols. In this paper we focus on their production, chemical analysis (spectrophotometry, HPLC, HPTLC, GC/MS, etc.) of flavonoids and phenolic acids, all of which enable authentication and geographical traceability of propolis and wine. This represents the basis for quality control and regulatory framework for any dietary supplement claiming to have beneficial health effectiveness.

Desirability analysis was performed in order to find a set of levels of the predictor variables (molecular descriptors) that maximizes the desirability of the responses on the dependent variable (studied inhibitory activities). The best QSAR models for the inhibition of α-glucosidase by polyphenols and anti-malarial activity of synthetic tri-pyrrole derivatives (prodiginines) were used for analysis. Predicting responses on the dependent variable were obtained by fitting the observed responses using an equation based on the levels of the independent variables (descriptors). Subsequently, the levels of the independent variables that simultaneously produce the most desirable predicted responses on the dependent variable were found. Overall desirability was computed as the geometric mean of the individual desirability. Desirability profiles consist of a series of graphs, one for each independent variable, of overall desirability scores at different levels of one independent variable, holding the levels of the other independent variables constant at specified values. Inspection of the desirability profiles shows which levels of the predictor variables produce the most desirable predicted responses on the dependent variable. Spline method was selected for fitting the desirability function and contours maps. The contour plots show the levels of overall response desirability produced in different regions of the plane defined by pairs of independent variables. Each region of the plane represents a different combination of the levels of the two variables. Desirability analysis was carried out with STATISTICA 7.0.

Grape berries, variety Limberger, produced in two vineyards (Ilok and Feričanci) located in eastern part of Croatia (Slavonia) during 2010. year were analysed for total polyphenols (TP), total anthocyanins (TA), and antioxidant activity (AOA) during the berry ripening. The main objective of this study was to investigate the influence of grape maturity on total polyphenolic and total anthocyanins content, as antioxidant activity of the grapes, their mutual relation, and relations with pH, sugar content, and weather conditions. Significant correlation between TP and TA was observed only for the grapes from Ilok (r = 0.92). Good correlation was found for the TA and sugar content in grapes (r = 0.90 Ilok, r = 0.83 Feričanci), TA and pH (r = 0.89 Ilok, r = 0.80 Feričanci), and between TA and daily mean temperature (r = 0.70 Feričanci, r = 0.89 Ilok). Significant correlation was not observed between AOA and total polyphenols (r = 0.69, Ilok ; r = 0.24, Feričanci). Slightly higher correlation was observed between antioxidant activity and total anthocyanins content (r = 0.73, Ilok ; r = 0.49, Feričanci). Those results imply on conclusion that antioxidant activity of grapes have a relation with group of polyphenols with high antioxidant activity and which concentration declines after vérasion.

Quantitative structure-property relationship (QS PR) models that relate hydrophilicity and lipophilicity of nineteen polyphenols with descriptors derived from optirnized three- dimensional molecular structures were developed. The 3D structures of polyphenols were optirnized applying the HyperChem 8.0 (Hypercube Inc.) us ing AMI method. Several physico-chernical parameters were calculated with HyperChem: the energy of the highest occupied (EHOMO) and lowest unoccupied molecular orbital (ELUMO), difference between EHOMO and ELUMO (GAP), the heat of formation (Hf) , and hydration energy (EHyDR). Applying the Dragon program, different group of molecular descriptors have been calculated: geometrical, 3D-MoRSE, Randic molecular profiles, GETA WAY, RDF, WHIM, and BCUT descriptors. Selection of descriptors based on best-subset method and multiple regression analysis was performed us ing the program Statistica 7.0 (StatSoft, Inc.). The generated QSPR model s were validated by leave-one-out cross-validation procedure using the CROMRsel (Rugjer Bošković Institute, Zagreb). This study has revealed that the hydrophilicity of polyphenols is generally dependent on the 3D- distribution of atornic electronegativity, polarizability, as well as on hydration energy of molecule. QSPR study of lipophilicity indicates about importance of the three- dimensional distribution of atornic mass and shape of molecule. 3D descriptors can be used successfully for modeling of hydrophilicity and lipophilicity of polyphenols, especially for data sets that include stereoisomers and hardly available compounds.

Diabetes mellitus is a chronic disease caused by inherited and/or acquired deficiency in insulin secretion and/or by decreased responsiveness of the organs to secreted insulin. Such a deficiency results in increased blood glucose levels that in turn can damage many of the body's systems, including blood vessels and nerves. Small intestinal a- glucosidase and pancreatic a-amylase are key enzymes of dietary carbohydrate digestion in humans. Inhibitors of these enzymes may be effective in retarding carbohydrate digestion and glucose absorption to suppress postprandial hyperglycaemia. Some polyphenols are well known inhibitors of intestinal a-glucosidase. The aim of this study was to derive a Quantitative Structure-Activity Relationship (QSAR) analysis for a-glucosidase inhibition potential of 48 polyphenols and their derivates. “Two- dimensional” (2D), “three-dimensional” (3D) molecular descriptors, quantum chemical descriptors, and physicochemical parameters, derived from optimised three-dimensional structure, have been calculated applying the PCLIENT (an on-line version of Dragon program) and HyperChem 8.0. Multiple regression analysis was performed using STATISTICA 7.0. Selection of predictor variables for multiple regression was performed by best-subset method. Dataset was divided into training set and test by manual selection and by cluster analysis, and then both method have been compared. The generated QSPR models were validated by leave- one-out cross-validation procedure using the CROMRsel (Rugjer Bošković Institute, Zagreb). Presented QSAR could be a useful for the design of new molecules more efficient in inhibition of enzymes responsible for the glucose production from carbohydrates. Also, this study will be helpful in illumination of antihyperglycemic effects of certain medicinal plants and food.

This work describes the QSAR study of lipid peroxidation inhibitory effect of catechins, anthocyanidins and anthocyanins using molecular descriptors and physicochemical parameters derived from optimised three-dimensional structure, since that set of studied compounds contains stereoisomers with different activities. Six groups of 3D descriptors have been used to generate QSAR models: geometrical, 3D-MoRSE, Randic molecular profiles, GETAWAY, RDF and WHIM descriptors. The 3D molecular descriptors and physicochemical parameters have been calculated applying the on-line software Parameter Client and HyperChem 8.0. The primary selection of 3D molecular descriptors and physicochemical parameters was based on their ability to discriminate stereoisomers. Further selection of predictor variables for multiple regression was performed by the best-subset and forward stepwise method. The best-developed QSAR models consisted of geometrical, RDF and Randic molecular profiles descriptors. Those descriptors could be used for the prediction of the biological activity of catechin stereoisomers and their derivates. The obtained models suggest that the inhibitory effect of studied compounds is related to the shape of the molecule and the three-dimensional distribution of atomic mass in the molecule.

Due to importance of three-dimensional (3D) shape of molecules for passive diffusion through the biological membranes, our attempt was to develop a quantitative structure- property relationship (QSPR) models that relates hydrophilicity (Hy) and lipophilicity (log P) of 19 polyphenols present in wine, with descriptors derived from an optimized 3D molecular structures. The aim of this study was also to correlate the experimentally determined log P values for polyphenols (taken from web database, http://chem.sis.nlm.nih.gov/chemidplus/) and values that are calculated using four different programs: HyperChem (log PHyp), MLOGP, ALOGP, and CLOGP. The 3D structures of 19 polyphenols were optimized applying the HyperChem 8.0 (Hypercube Inc.) using AM1 method. Several physico-chemical parameters were calculated with HyperChem: the energy of the highest occupied (EHOMO) and lowest unoccupied molecular orbital (ELUMO), difference between EHOMO and ELUMO (GAP), the heat of formation (Hf), and hydration energy (EHYDR). Applying the Dragon program, different group of molecular descriptors have been calculated: geometrical, 3D-MoRSE, Randic molecular profiles, GETAWAY, RDF, WHIM, and BCUT descriptors. Selection of descriptors based on best-subset method and multiple regression analysis was performed using the program Statistica 7.0 (StatSoft, Inc.). The generated QSPR models were validated by leave-one-out cross-validation procedure using the CROMRsel (Rugjer Bošković Institute, Zagreb). The best model for hydrophilicity contains the two 3D- MoRSE descriptors: Mor13e and Mor13e. The best agreement with experimentally observed log P values was obtained with CLOGP values. However, the most appropriate model was achieved for the ALOGP using two variables: BELe1 (BCUT) and RTm (GETAWAY). Obtained models imply that lipophilicity and hydrophilicity of polyphenols is mainly influenced by the presence of different substitutions on the basic structure of phenolic acids and flavonoids.

Vino je bogat izvor različitih skupina polifenola koje uključuju fenolne kiseline, flavonoide i trihidroksistilben - resveratrol. U posljednje vrijeme zanimanje za te supstancije potaknuto je brojnim dokazima o njihovim pozitivnim učincima na zdravlje čovjeka. Do sada su korištene različite metode analize polifenola u vinu uključujući kromatografske, spektrofotometrijske metode i elektrokemijske metode. U ovom članku opisane su ukratko metode priprave uzoraka i najnovija dostignuća u analizi polifenola u vinu, temeljnim kromatografskim metodama: tankoslojnom kromatografijom (TLC), tekućinskom kromatografijom visoke djelotvornosti (HPLC) uz različite tehnike detekcije, te plinskom kromatografijom (GC). Kao posebna tehnika, također je spomenuta i kapilarna elektroforeza koja se odnedavno koristi za analizu polifenola u vinu.

Zeolites are crystalline hydrated aluminosilicates of alkali and alkaline earth cations, consisting of three-dimensional frameworks of SiO4 and AlO4 tetrahedra linked through the shared oxygen atoms to form an open crystal lattice with approximately uniform pores of molecular dimensions. The dietary use of naturally occurring or synthetic zeolites has been reported to improve feed efficiency, thus leading to a beneficial growth response in pigs. Three groups of weaned piglets (N=60), crossbreed (LWxSL)x Pietrein, the same sex proportions, aged 28 to 70 days were involved in the trial. Tribomechanically activated zeolite clinoptilolite (0.2% was added to the first experimental group, modified clinoptilolite was added to the second experimental group in the same concentration. Piglets in all groups were of similar body weights during both experimental periods. Plasma glucose, urea, total protein, sodium, potassium, chloride concentration were changed with the diet added modified clinoptilolite.

Diabetes mellitus is a chronic disease caused by inherited and/or acquired deficiency in insulin secretion and/or by decreased responsiveness of the organs to secreted insulin. Such a deficiency results in increased blood glucose levels than in turn can damage many of the body's systems, including blood vessels and nerves. Small intestinal a- glucosidase and pancreatic a-amylase are key enzymes of dietary carbohydrate digestion in humans. Inhibitors of these enzymes may be effective in retarding carbohydrate digestion and glucose absorption to suppress postprandial hyperglycaemia. Postprandial glucose levels impact on serum levels of glycosylated haemoglobin (HbA1c), an established risk indicator for microvascular disease. Effective control of postprandial hyperglycaemia is therefore important for reducing this risk. Some flavonoids are known to inhibit intestinal a-glucosidase and pancreatic a-amylase. The aim of this study was to derive a Quantitative Structure-Activity Relationship (QSAR) analysis for a-glucosidase inhibition potential of 18 flavonoids. Two-dimensional (2D), three- dimensional (3D) molecular descriptors, quantum chemical descriptors, and physicochemical parameters, derived from optimized three- dimensional structure, have been calculated applying the PCLIENT (an on-line version of Dragon program) and HyperChem 8.0. Indicator variables, that mark the number and position of OH groups in flavonoid molecule, also have been included in QSAR analysis. Multiple regression analysis was performed using STATISTICA 7.0. Selection of predictor variables for multiple regression was performed by best-subset method. Best-developed bi-parametric (r2=0.80 ; F=30.35) and tri-parametric (r2=0.84 ; F=25.42) QSAR models are consisted of: indicator variables, 3D-MoRSE, topological, and GETAWEY descriptors. The obtained models demonstrated a positive influence of hydroxylation at the 4'- position and number of electronegative atoms in the molecule on inhibitory activity of studied compounds. Size and shape of the molecule, as well as three-dimensional charge distribution inside of molecule also play an important role in inhibition of a-glucosidase by flavonoids. Presented QSAR could be a useful for the design of new molecules more efficient in inhibition of enzymes responsible for the glucose production from carbohydrates.

U svrhu istraživanja sastava najvažnijih polifenola u vinima iz Hrvatske razvijene su metode tankoslojne kromatografije (TLC) i tekućinske kromatografije visoke djelotvornosti (HPLC). Priprava uzoraka provedena je ekstrakcijom s dietil-eterom pri pH 2. Ukupni sadržaj polifenola određen je Folin-Ciocalteuovom metodom. Najprikladniji razvijač ψ (benzen, etil-acetat, mravlja kiselina) = 30 : 15 : 5, odabran dendrogramom, korišten je u svim daljnjim ispitivanjima. Identifikacija polifenola na TLC kromatogramu provedena je promatranjem boja ili fluorescencije mrlja pod UV svjetlom. Kvantitativno određivanje jedanaest razdvojenih polifenola na TLC pločama provedeno je skenirajućom denzitometrijom. Razrađena je tekućinskokromatografska metoda obrnutih faza uz gradijentno ispiranje i uz primjenu UV detektora s nizom dioda (DAD) za određivanje devetnaest polifenola u ekstraktima vina. Rezultati analize ukazuju da vina iz Dalmacije imaju najveći sadržaj polifenola. Istraživani su odnosi između strukture i fizikalno-kemijskih svojstava (QSPR), te strukture i fizikalno-kemijskih svojstava s antioksidacijskom aktivnosti polifenolnih supstancija u vinu (QSAR).

Catechins, anthocyanidins and their glycoside – anthocyanins, compounds that belong to the natural antioxidant - polyphenols, present in foods of plant origin, are potentially beneficial to human health. Antioxidative effects of those phytochemicals are based on the ability to scavenge different free radicals or the protection of biological molecules against oxidation. In the present study lipid peroxidation inhibitory effect [1] of mentioned polyphenols is correlated with molecular descriptors and physicochemical parameters calculated from three-dimensional structure, since studied compounds contain stereoisomers with different activities. Six groups of 3D descriptors have been used to generate a quantitative structure-activity relationship (QSAR) models: geometrical ; GETAWAY (Geometry, Topology, and Atom Weights AssemblY) ; 3D-MoRSE, RDF (Radial Distribution Function) descriptors ; Randic molecular profiles and WHIM (WeigHted Covariance Matrices) descriptors. Geometries of molecules were optimized using the molecular mechanic MM+ force field method applying the HyperChem 8.0 Evaluation software package. The 3D molecular descriptors used in this study have been calculated applying the on-line software Parameter Client (PCLIENT), an extension of E-Dragon. Physicochemical parameters (connolly accessible area, connolly molecular area, connolly solvent excluded volume, ovality, volume and surface area of molecule and hydration energy) were calculated using HyperChem 8.0 and Chem3D Ultra 10 Trial Version. Only 3D molecular descriptors and physicochemical parameters with ability to discriminate stereoisomers were chosen for multiple regression analysis. The selection of predictor variables for multiple regression was performed by best-subset method. Present work should provide the better understanding of structural factors that relate the antioxidant activity of polyphenols.

ANALYSIS OF BIOLOGICALLY ACTIVE POLYPHENOLS IN WINES FROM CROATIA V. Rastija and M. Medić- Šarić Introduction Polyphenols are secondary plant metabolites that attract great interest due to their biological activities, such as antioxidant activity, anti-inflammatory, antimicrobial and antifungal action. There is evidence that some of them have positive effect against a large variety of degenerative processes, such as cancer, atherosclerosis, cardiovascular disorders, age-related macular degeneration and cognitive decline in aging. Wines contain large amount of polyphenols such as phenolic acids, flavones, flavonols, catechins, anthocyanins, procyanidins and resveratrol. Considering the importance of biologically active polyphenols in wine, it is necessary to develop an accurate and rapid method for their analysis. Materials and Method Twelve commercial wines, vintage 2002, from three different wine-growing Sub-regions of Croatia were analyzed. Total polyphenols were analyzed according to the Folin– Ciocalteu method. Samples for chromatographic analysis were prepared by extraction of wines with diethyl ether at pH 2. A reversed-phase high performance liquid chromatographic (HPLC) method that uses gradient elution and diode array detection (DAD) to determine 7 phenolic acid and eight flavonoids in wine extracts was developed. The chromatographic separation of these polyphenols was performed in a single run with flow rate at 1 ml/min and UV-visible spectra were recorded between 250 -500 nm and compared with those of standards. Wavelengths used for quantification were 280 nm and 360 nm. Results Analysis of total polyphenols by Folin– Ciocalteu method implied that wines produced in Mediterranean part of Croatia have a highest polyphenolic content. White wines contain significantly lower amounts of total polyphenols (400.8 mg/L) compared with red wines (1665.131 mg/L). Applied HPLC method allows the separation of 19 polyphenols with antioxidant properties from wine extracts in a single run. The most abundant polyphenol is gallic acid (0.7 – 26.9 mg/L). Biologically most active compounds, catechin and trans- resveratrol were present in each of analyzed wine. Highest concentrations of those compounds, together with one of the most potent antioxidant - quercetin, were determined in wines from Dalmatia. Since the vintage of the examined wines was identical, the observed quantitative differences are related to the grape variety, geographical origin, growing and winemaking procedures. Conclusion The present study, which utilized new HPLC method for simultaneous determination of fifteen polyphenols and analysis of total polyphenols, demonstrates that the wines made from Croatia contain a significant amount of biologically active polyphenols and certainly, moderate and regular consumption of those wines (in particular red wine) can reduce risk of some diseases. However, wines made in Dalmatia contain a highest level of polyphenols as a result of dry mediterranean clime with high cluster sun exposure, so those wines could have highest positive effects on human health.

Thin-layer chromatography (TLC) method are studied for determination of phenolic compounds in two samples of commercially available wines from the Croatia. Sample preparation method using liquid-liquid extraction with diethyl ether at pH 2.0 was used. Extracts and standard solutions were applied on silica gel 60 F254 TLC plates (20 × 20 cm). The efficiency of eleven mobile phases, used for this purpose, has been tested by three mathematical techniques: calculation of the information content (I) derived from Shannon 's equation ; determination of discriminating power (DP) and formation of clusters and dendrogram. It has been shown that the most favourable mobile phase for separation phenolic compounds in extract of wine “ Frankovka” is benzene-ethyl acetate-formic acid, 30 + 15 + 5 (v/v), while for wine "Merlot" optimal mobile phases are chloroform-methanol-formic acid, 15 + 3 + 2 (v/v) and ethyl acetate-chloroform-formic acid, 24 + 21 + 5 (v/v). Six phenolic compounds have been identified in the tested samples.

Three new series of mixed-ligand clusters of the [M_6X_12)X_2(RCN)_4] (M = Nb, Ta ; X = Cl, Br ; R = Et, n-Pr, n-Bu) composition have been prepared. It is supposed that four nitrile molecules and two halogene atoms are coordinated to the terminal octahedral coordination sites of the [M_6X_12]^2+ unit.

Opisane su reakcije heksanuklearnih halogenidnih kompleksa niobija i tantala s nitrilima: valeronitrilom i benzonitrilom, te s kompleksnim ciano-spojevima: kalijevim heksacianoferatom(II) i kalijevim tetracianonikolatom(II).

Istraživane su reakcije ciano-kompleksa K_4[Fe(CN)_6] i K_2[Ni(CN)_4] s heksanuklearnim halogenidnim spojevima niobija i tantala [(M_6X_12)X_2(H_2O)_4]x4H_2O (X = Cl, Br) u vodi, odnosno u smjesi metanol/voda.

U ovom su radu istraživane reakcije etanolnih prekursora [(M_6X_12)X_2]x6C_2H_5OH (M = Nb, Ta ; X = Cl, Br) s valeronitrilom i benzonitrilom.

Istraživanje je provedeno 2021. godine na pokušalištu Mandićevac, vinogorje Đakovo. Cilj istraživanja bio je utvrditi utjecaj različitih rokova berbe na neke kvantitativne (urod, masa 100 bobica) i kvalitativne (sadržaj ukupne topive suhe tvari, realni aciditet mošta, kiselost mošta, te ukupni polifenoli i antocijani) odlike kultivara cabernet sauvignon. Berba je obavljena u tri roka: 23.09.2021., 29.09.2021. i 05.10.2021. i to na načina da je metodom slučajnog odabira uzorkovan prosječni uzorak grožđa u svakom navedenom roku berbe. Prosječna masa grozda bila je najveća u prvom roku berbe, kao i masa 100 bobica. Sadržaj ukupne topive suhe tvari mošta povećavao se odlaganjem berbe, dok se vrijednost realnog aciditeta mošta kretala u prihvatljivim granicama i sukladno smanjenju kiselosti mošta, odnosno padu sadržaja jabučne i vinske kiseline mošta. Najveći sadržaj ukupnih polifenola i antocijana zabilježen je u prvom roku berbe., Research was conducted in 2021., in vineyard near Đakovo. The aim of the research was to determine the influence of different harvest dates on some quantitative (yield, weigth of 100 berries) and qualitative (total soluble dry matter of must, real acidity of must, must acidity, total polyphenols and total anthocyanins) characteristic of cabernet sauvignon cultivar. The harvest was carried out in three terms: 23.09.2021., 29.09.2021. and 05.10.2021. in such a way that an averange sample of grapes was harvest in each of mentioned terms using the method of random selection. The average weight of spring of grapes was the highest in the first period of harvest, as well as the weight of 100 berries The content of total soluble dry matter of the must grew with delay of the harvest, and the value of the real acidity of the must was within acceptable limits and in accordance with decrease in malic and tartaric acid content. The highest value of the total polyphenols and total anthocyanins was recorded in the first period of harvest.

Istraživanje je provedeno na sorti merlot, 2021. godine. Kroz tri različita roka berbe na pokušalištu Mandićevac u vinogorju Đakovo. Cilj je bio utvrditi utjecaj različitih roka berbe na kvalitativne odlike kao što su: ukupna topiva suha tvar, realni aciditet mošta, ukupna kiselost mošta, sadržaj ukupnih polifenola i sadržaj ukupnih antocijana. Berba je obavljena u tri različita rok: 10.09.2021., 22.09.2021. i 04.10.2021., metodom slučajnog odabira. Ubran je prosječan uzorak grožđa u svakom od navedenih rokova. Rezultati analiza su pokazali sljedeće: s odmakom berbe sadržaj ukupne topive suhe tvari mošta je rastao, a realni aciditeta mošta i ukupne kiselosti mošta su se kretale uprihvatljivim granicama. Najveći sadržaj ukupnih polifenola i ukupnih antocijana zabilježen je u drugom rokuberbe, što ga čini najboljim izborom s aspekta sadržaja ukupnih polifenola i ukupnih antoc, The research was conducted on the Merlot variety in 2021. Through three different harvest periods at the Mandićevac trial site in the Đakovo vineyard. The goal was to determine the influence of different harvest dates on qualitative characteristics such as: total soluble dry matter, real must acidity, total must acidity, total polyphenol content and total anthocyanin content. Harvesting was done on three different dates: September 10, 2021, September 22, 2021. and 04.10.2021, by random selection method. An average sample of grapes was collected in each of the mentioned terms. The results of the analyzes showed the following: as the harvest progressed, the total soluble dry matter content of the must increased, and the real acidity of the must and the total acidity of the must were within acceptable limits. The highest content of total polyphenols and total anthocyanins was recorded in the second harvest period, which makes it the best choice in terms of content of total polyphenols and total anthocyanins.

Cilj istraživanja bio je utvrditi utjecaj različitih rokova berbe na neke kvalitativne (ukupna topiva suha tvar, realni aciditet mošta, ukupna kiselost, ukupni poloifenoli, ukupni antocijani) odlike kultivara Frankovka u vinogorju Đakovo u 2021. godini. Berba je obavljena u tri roka (10.09.2021., 22.09.2021., 04.10.2021.) na način da je metodom slučajnog odabira ubran prosječni uzorak grožđa u svakom od navedenih rokova. Rezultati analiza obrađeni su opisnom statistikom. Sadržaj ukupne topive suhe tvari mošta rastao je sa odmakom berbe, a vrijednost realnog aciditeta mošta kretala se u prihvatljivim granicama. Najviša vrijednost ukupne kiselosti mošta, sadržaja ukupnih polifenola i antocijana zabilježena je u prvom roku berbe., The aim of the research was to determine the influence of different harvest dates on some qualitative (total soluble dry matter, real acidity of must, total acidity, total polyphenols, total anthocyanins) characteristics of the Blaufränkisch cultivar in the Đakovo vineyards in 2021. The harvest was carried out in three terms (10/09/2021, 22/09/2021, 04/10/2021) in such a way that an average sample of grapes was harvested in each of the mentioned terms using the method of random selection. Basic of the results of the analyzes were processed by descriptive statistics. descriptive statistics were made on the collected samples. The content of total soluble dry matter of the must grew with the delay of the harvest, and the value of the real acidity of the must was within acceptable limits. The highest value of the total acidity of the must, the content of total polyphenols, and anthocyanins was recorded in the first period of harvest.

Lan je jednogodišnja biljka iz porodice Linaceae, pripada rodu Linum koji broji preko 200 vrsta od kojih se neke uzgajaju kao ukrasne dok se za proizvodnju vlakna koristi predivi lan (Linum usitatissimum L.). Cilj ovog završnog rada bio je istražiti utjecaj predsjetvenog tretmana 3-etoksikarbonil i 3-metoksikarbonil derivata kumarina na klijavost sjemena predivog lana. Predtretman sjemena izvršen je močenjem sjemena u vodi, 2 % vodenoj otopini dimetilsulfoksida, 1,0 mM otopinama 3-etoksikarbonil i 3-metoksikarbonil derivata kumarina tijekom 15 minuta. Sjeme predivog lana potom je naklijavano 7 dana nakon čega su izmjereni klijavost, masa, dužina korjenčića, stabljičice i ukupna dužina klijanca. Istraživanje je pokazalo da ispitivani 3-etoksikarbonil i 3-metoksikarbonil derivati kumarina pokazuju značajan utjecaj samo na klijavost sjemena predivog lana dok na ostale parametre nisu značajno utjecali. Najveće vrijednosti za sve ispitivane parametre utvrđene su za klijance predivog lana predtretiranog 1.0 mM etil 6-bromo-2-okso-2H-kromen-3-karboksilatom. Prema dobivenim rezultatima može se zaključiti da se ispitani derivati kumarina mogu koristiti kao mogući predtretman za zaštitu sjemena predivog lana bez značajnog nepovoljnog utjecaja na rani rast i razvoj klijanaca, Flax is an annual plant from the family Linaceae, belonging to the genus Linum, which has over 200 species, some of which are grown for decorative purposes, while fiber flax (Linum usitatissimum L.) is used for fiber production. The aim of this study was to investigate the effect of pre-sowing treatment of 3-ethoxycarbonyl and 3-methoxycarbonyl coumarin derivatives on germination of flax seeds. Seed priming was performed by soaking the seeds in water, 2% dimethyl sulfoxide, 1.0 mM solutions of 3-ethoxycarbonyl and 3-methoxycarbonyl coumarin derivatives for 15 minutes. The flax seeds were then germinated for 7 days after which germination, weight, root length, stems and total seedling length were measured. The study showed that the tested 3-ethoxycarbonyl and 3-methoxycarbonyl derivatives of coumarin show a significant effect only on the germination of flax seeds, while other parameters were not significantly affected. The highest values for all tested parameters were found for flax seedlings pretreated with 1.0 mM ethyl 6-bromo-2-oxo-2Hchromene-3-carboxylate. According to the tained results, it can be concluded that the tested coumarin derivatives can be used as a possible pre-treatment for the protection of flax seeds without a significant adverse effect on early growth and development of seedlings.

Voda je postala najznačajniji globalni resurs u današnjem vremenu, no njezini potencijali u proizvodnji hrane još uvijek nisu dovoljno iskorišteni i učinkovito organizirani. Poljoprivreda, kao jedna od najvećih grana biotehničkih znanosti značajan je potrošač vode. U budućnosti se očekuje da će klimatske promjene pojačati potrebu za navodnjavanjem zbog nestašica vode, te uzrokovati dodatni teret na korištenje vode i zemljišta. Važno je osigurati održivo korištenje voda, budući da je voda iscrpljiv resurs. Sveprisutni su nezapamćeni pritisci i konkurencija za vodne resurse upravo zbog faktora rasta i mobilnosti stanovništva, ekonomskog razvoja, urbanizacije. Danas se u Republici Hrvatskoj navodnjavaju relativno male poljoprivredne površine u odnosu na potrebe i kapacitete – imamo bogat vodni resurs te plodna tla, međutim poljoprivreda stagnira. Pročišćavanje otpadnih voda je inkorporiranje otpadnih voda pri čemu nastaje voda koja se koristi u druge svrhe. Upotreba pročišćenih otpadnih voda smanjuje potrošnju vode, energije, te štedi novac. Pročišćene otpadne vode mogu se koristiti u poljoprivredi, akvakulturi, industriji, komunalnim potrebama ali i za vodoopskrbu. Prema tome, upotreba pročišćenih otpadnih voda bila bi potencijalno rješenje za integraciju u planiranju ali i razvoju sustava navodnjavanja u poljoprivredi. Iskorištenje vode iz HEP proizvodnje ima velik potencijal te široku namjenu za korištenje u skoroj budućnosti, Water has become the most important global resource today, but its potential in food production is still not sufficiently exploited and efficiently organized. Agriculture, as one of the largest branches of biotechnical sciences, is a significant consumer of water. In the future, climate change is expected to increase the need for irrigation due to water shortages, and cause an additional burden on water and land use. It is important to ensure the sustainable use of water, as water is a depleted resource. Unprecedented pressures and competition for water resources are ubiquitous precisely due to the factors of growth and mobility of the population, economic development, urbanization. Today, in the Republic of Croatia, relatively small agricultural areas are irrigated in relation to needs and capacities - we have a rich water resource and fertile soils, but agriculture is stagnating. Wastewater treatment is the incorporation of wastewater to produce water that is used for other purposes. The use of treated wastewater reduces water consumption, energy, and saves money. Treated wastewater can be used in agriculture, aquaculture, industry, utilities, but also for water supply. Therefore, the use of treated wastewater would be a potential solution for integration in the planning and development of irrigation systems in agriculture. The use of water from HEP production has great potential and a wide purpose for use in the near future.

Istraživanje je provedeno na pokušalištu Fakulteta agrobiotehničkih znanosti Osijek, u Mandićevcu 2019. godine. Cilj istraživanja bio je utvrditi utjecaj različitog intenziteta kasne defolijacije utjecati na neke kvantitativne i kvalitativne odlike kultivara Traminac, Chardonnay i Sauvignon bijeli. Primijenjeni tretmani bili su defolijacija četiri lista od osnove mladice, osam listova od osnove mladice te kontrolnim tretman. Analizirani paramteri bili su slijedeći: prosječni urod po trsu (kg), prosječni broj grozdova po trsu, prosječan sadržaj šećera u moštu (°Oe), ukupna kiselost mošta i realni aciditet mošta. Na temelju dobivenih rezultata i obrađenih statističkih podataka utvrđeno je kako s obzirom na intenzitet kasne defolijacije nema statistički značajnih razlika između ispitivanih parametara unutar istraživanih sorata., The research was conducted at the experimental site of the Faculty of Agrobiotechnical Sciences Osijek, in Mandićevac in 2019. The aim of the study was to determine how different intensities of late defoliation will affect on some quantitative and qualitative characteristics of cultivars Traminac, Chardonnay and Sauvignon blanc. The influence of defoliation intensity was investigated by applying the treatment of removing four leaves from the base of the sprout, eight leaves from the base of the sprout and the control treatment. The parameters we analyzed are as follows: average yield per plant (kg), average number of bunches per plant, average sugar content in the must (° Oe), total must acidity and real must acidity. Based on the obtained results and processed statistical data, it was determined that with regard to the intensity of late defoliation, there are no significant differences between the examined parameters within the investigated cultivars.

U Nadinskom blatu 2020. godine istraživan je utjecaj različitih opterećenja trsa na kvantitativne i kvalitativne parametre sorte Cabernet sauvignon. Zaključeno je sljedeće: najveće opterećenje od 12 pupova po trsu rezultiralo je urodom od (5007 kg/ha) dok je najmanji urod zabilježen kod opterećenja od 8 pupova čiji urod je bio niži za 26,33% . Najviši sadržaj ukupne topive suhe tvari u moštu zabilježen je kod tretmana A2 s opterećenjem od 10 pupova (21,3° Brix-a) dok su preostala dva tretmana ostvarila istu vrijednost sadržaja ukupne topive suhe tvari mošta od 21°Brix-a. Ukupna kiselost mošta nije se značajno mijenjala promjenom opterećenja trsa, no zamijećen je trend opadanja kiselosti sa smanjenjem opterećenja. Vrijednosti ukupne kiselosti kod najvećeg opterećenja A1 iznosila je 4,75 zatim 4,6 kod opterećenja A2, dok je kod najmanje opterećenog tretmana A3 iznosilo 4,3 g/l. Najviši pH zabilježen je kod tretmana od 10 ostavljenih pupova odnosno A2 i iznosilo je (3,39), dok je pH tretmana s najmanjim opterećenjem A3 iznosio 3,08. Razlike za realni aciditet mošta nisu bile značajne. Statistički značajne razlike nisu zabilježeni ni u sadržaju ukupnih polifenola i antocijana u pokožici grožđa između tretmana., The experiment was set up in Nadinsko blato in 2020, and different bud loads on Cabernet sauvignon varieties were observed. The aim of the study was to determine how a different load affects yield and some qualitative characteristics (must sugar content, pH, acidity, total phenolic and anthocyanin content). It was concluded that the highest load of 12 buds per vine gave a yield of (5007kg / ha) while the lowest yield had the lowest load of 8 buds whose yield was lower by 26.33%. The highest total soluble solid content in the grape juice was recorded in the A2 treatment with a load of 10 buds (21.3 ° Brix) while the remaining two treatments achieved the same value of the total soluble solid content in the grape juice of 21 ° Brix. The total acidity of the grape juice was not significant with the change of treatment. However, a trend of decreasing acidity with decreasing load was observed. The values of total acidity at the highest load A1 were 4.75, then 4.6 at the load A2, while at the least loaded treatment A3 was 4.3 g/l. The highest pH was recorded in the treatment of 10 left buds or A2 and was 3.39, while the pH treatment with the lowest load A3 was 3.08. The differences for the real acidity of the grape juice were not significant. Also there were no statistically significant differences observed in the content of polyphenols and anthocyanins in the grape skin between treatments.

Pokus za istraživanje utjecaja defolijacije i uklanjanja zaperaka na pokazatelje kvalitete mošta (sadržaj šećera, ukupnu kiselost i pH vrijednost) kultivara Muškat žuti je postavljen po slučajnom bloknom rasporedu u vinogradu obitelji Žmegač u Varaždinskom vinogorju 2019. godine. Istraživanje je provedeno na ukupno 72 trsa. Jednu repeticiju činilo je šest trsova, pa smo imali po četiri repeticije za defolijaciju, zalamanje zaperaka i kontrolu. Nakon provedene laboratorijske analize uzoraka napravljena je analiza varijance prema slučanjom bloknom rasporedu. Značajne i visoko značajne razlike između tretmana utvrđene su za sadržaj šećera, ukupnu kiselost i pH vrijednost mošta. Kod kontrole utvrđen je značajno veći sadržaj šećera u odnosu na defolijaciju i zalamanje zaperaka. Visoko značajne razlike za ukupnu kiselost mošta utvrđene su za tretman zalamanja zaperaka odnosu na defolijaciju i kontrolu.Visoko značajna razlika za pH vrijednost mošta utvrđena je za kontrolu u odnosu na tretman defolijacije i zalamanje zaperaka., Experiment for investigation of defoliation and sprout removal on some must quality parameters (sugar, total acidity, pH value) cultivar Muscat Yellow was set up randomized block design in the Žmegač family vineyard in Varaždin vineyards in 2019. Investigation was conducted on 72 vines in total. One rehearsal consisted of six vines, so we had four rehearsals each for defoliation, sprout removal and control. After the laboratory analysis of the samples, the analysis of variance according to randomized block design. Significant and highly significant differences between the treatments undertaken were obtained for the sugar content, the total acidity and the pH value. During the control, a significantly higher sugar content was found in relation to defoliation and shoots removal. Highly significant differences for the total acidity of the must were found for the treatment of shoots removal in relation to defoliation and control. A highly significant difference for the pH value of must was found for control in relation to the treatment of defoliation and shoots removal.

Pokus je postavljen 12. ožujka 2019. godine na demonstracijsko vinogradarsko – vinarskom pokušalištu Mandićevac (45°22´4,75´´N 18°12´46,35´´E), vinogorje Đakovo, u sklopu Fakulteta agrobiotehničkih znanosti Osijek. Svrha ovog istraživanja bila je prikazati kako će se različiti uzgojni oblici odraziti na kvalitetu mošta kultivara Traminac mirisavi, koji je cijepljen na podlogu SO4. Pokus je zahtjevao oblikovanje dva uzgojna oblika; dvokraki oblik uzgoja i Guyot, za svaki tretman po 16 trsova (ukupno 32 uzoraka za analizu), koji su nakon berbe izmošteni i analizirani u laboratoriju na kvalitativne pokazatelje; koncentraciju šećera, koncentraciju ukupnih kiselina te pH reakciju mošta. Klimatske prilike u godini koja je prethodila pokusu, bila je optimalnih uvjeta za diferencijaciju pupova. Godina u kojoj je izvršen pokus okarakterizirana je kao ekstremno topla godina, iznad prosječnih količina sunčanih sati, te iznad prosječnih količina oborina, s anomalijom pretjeranog vlaženja u mjesecu svibnju te rujnu, u usporedbi s višegodišnjim prosjekom.T testom je utvrđeno da postoje razlike visoko značajnog karaktera za koncentraciju šećera i pH reakciju mošta te značajne razlike za ukupne kiseline prosječnih vrijednosti između navedena dva tretmana. Učinci korištenja dvokrakog oblika uzgoja doveli su do visoko značajnog manjeg sadržaja šećera i manje vrijednosti pH rekcije mošta, te značajno veće koncentracije ukupnih kiselina u usporedbi sa sustavom uzgoja Guyot., The research was set up on March 12, 2019 at the demonstrative viticulture and winery probation, Mandićevac (45°22´4.75´´N 18°12´46.35´´E), Đakovo vineyard county, within the Faculty of Agrobiotechnical Sciences Osijek. The purpose of this research was to show how different forms of training methods will affect the quality of the must of the cultivar Gewürztraminer, which was grafted on SO4 rootstock. The experiment required formation of two training forms; two-armed (spur and cane) training form and Guyot, for each treatment of 16 replicates (a total of 32 samples for analysis), which were drained after harvest and tested in the laboratory for qualitative indicators; sugar concentration, total acid concentration and pH reaction of the must. The climatic conditions in the year preceding the experiment were optimal in terms of conditions for bud differentiation. The year in which the experiment was performed was characterized as an extremely warm year, above average amounts of sunshine hours, and above average rainfall, with an anomaly of excessive moistening in May and September, compared to the perennial average.The T test revealed that there are differences of a highly significant character for the sugar concentration and pH reaction of the must and significant differences for the total acids of average values between the two treatments. The effects of using the cane and spur training form led to a highly significant lower sugar content and lower value of pH reaction of the must, and a significantly higher concentration of total acids compared to the Guyot training form.

Pirazoli su heterociklički spojevi koji su graĎeni od tri ugljikova atoma i dva dušikova atoma u susjednom poloţaju. Cilj ovog istraţivanja je bio utvrditi hoće li derivati pirazola kao potencijalni novi pesticidi imati djelovanje na rast i razmnoţavanje Bacillus subtilis. U istraţivanju je korišteno 10 derivata pirazola, a rezultati su pokazali da niti jedan od njih nema inhibitornu aktivnost na rast Bacillus subtilis, koja predstavlja korisnu bakterijsku populaciju tla. Potrebna su daljnja istraţivanja kako bih se utvrdilo djelovanje pirazola i na druge korisne mikroorganizme tla., Pyrazoles are heterocyclic compounds that are made up of three carbon atoms and two nitrogen atoms in an adjacent position. This study aimed to determine whether they would want to get pyrazoles as potential new pesticides to affect and reproduction Bacillus subtilis.Ten pyrazoles derivatives were used in the study, and the results showed that none of them had inhibitory activity on the growth of Bacillus subtilis, which represents a beneficial bacterial population of the soil. Further research is needed to determine the effect of pyrazoles on other beneficial soil microorganisms as well.