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In this research paper, the total phenols (TP), flavonoids (TF), and tannins (TT) content in the acetone and ethyl acetate extracts of Najas marina L. and the identification and quantification of phenolic acids and flavonoids from the ethyl acetate extract were performed. Antioxidant, antimicrobial, and antibiofilm properties of the mentioned extracts were investigated in vitro. The genotoxic potential was analyzed in cultured human peripheral blood lymphocytes (PBL). The TP and TF content was higher in the ethyl acetate extract, dominated by quercetin (172.4 µg mg−1) and ferulic acid (22.74 µg mg−1), while the TT content was slightly higher in the acetone extract. Both extracts tested showed limited antioxidant effects compared to ascorbic acid. The strongest antibacterial activity was observed with Gram-positive bacteria, particularly Staphylococcus aureus (MIC and MMC at 0.31 mg ml−1) and S. aureus ATCC 25923 (MIC at

This is the first study on antioxidant and antibacterial activity of essential oils of A. sylvestris and A. pancicii against the human pathogens. In the oil of A. sylvestris, the main compounds wer...

In this paper, we investigated the hydrophobicity, ability to adhere to solvents and the pig epithelium and co-aggregation of members of family Enterobacteriaceae and Enterococcus faecalis KGPMF 49. The bacteria used in this study were isolated from traditionally made autochthonous cheese from Southeastern Serbia (Sokobanja). The percentage of adhered bacteria was different in three solvents (chloroform, ethyl acetate and xylene). The highest percentage was detected in the presence of chloroform, and the lowest percentage was detected in the presence of xylene (chloroform < ethyl acetate < xylene). A different degree of co-aggregation of enterobacteria with E. faecalis KGPMF 49 was observed. Klebsiella ornithinolytica KGPMF 8 demonstrated the highest percentage of co-aggregation with E. faecalis KGPMF49 (32.29%). Klebsiella pneumoniae KGPMF 13, K. ornithinolytica KGPMF 9 and Serratia marcescens biogp 1 KGPMF 19 were found to have the ability to adhere to the pig epithelium, whereas Escherichia coli KGPMF 22 showed no such ability. The ability to co-aggregate with other species and the ability to adhere to the pig epithelium are very important characteristics of the isolated bacteria.

Seven new zinc(II) complexes, K[Zn(dClQ)3]·2DMF (1), K[Zn(dClQ)3]·2DMF·H2O (2), [Zn(dBrQ)2(H2O)]2·DMF·H2O (3), [Zn(BrQ)2(H2O)]2·H2O (4), (HdClQ)2[ZnCl4]·2H2O (5), [Zn(dClQ)2(H2O)2]·H2O (6) and [Zn(CQ)2(H2O)2] (7) (5,7-dichloroquinolin-8-ol (dClQ), protonated 5,7-dichloroquinolin-8-ol (HdClQ), 5,7-dibromoquinolin-8-ol (dBrQ), 7-bromoquinolin-8-ol (BrQ), 5-chloro-7-iodoquinolin-8-ol (CQ)) have been prepared. All complexes were characterized by IR spectroscopy, elemental analysis and, except 7, by X-ray structure analysis. Stability of complexes in dimethyl sulfoxide was verified by NMR spectra. Antimicrobial activity was tested against nine strains of pathogenic bacteria, five mould species and two yeast species. Cytotoxic activity was tested against colon cancer cell line HCT 116 and non-cancerous cell line CCD-18Co. While all complexes showed higher cytotoxicity than cisplatin, poor selectivity to normal cells was observed.

This research examined in vitro probiotic potential of Lactobacillus curvatus isolates from fermented sausage originating in Southeast Serbia which was prepared using traditional production techniques. Strains of L. curvatus were isolated and identified at the level of species using API 50CHL sets and 16s rDNA sequencing, after which their probiotic potential was measured. The research consisted of the examination of isolate survival rates in the gastrointestinal tract, synthesis of biogenic amines, the growth on the media with different quantities of phenol, antibiotic resistance test, and antimicrobial activity against clinical strains of Pseudomonas spp., Proteus spp., Enterobacter spp., Escherichia coli and Listeria monocytogenes. The examined isolates have shown a good survival rate at low pH in the simulated stomach and small intestine conditions. Synthesis of biogenic amines was exhibited by the isolate sk1-10, which had a positive reaction to histidine. Analyzed isolates grew well on media with 0.1% and 0.2% of phenol, L.curvatus sk1-8 and sk5-2 have grown in media with 0.3% phenol. All tested isolates have exhibited high sensitivity to most analyzed antibiotics (tetracycline, amoxicillin, ceftriaxone, erythromycin, penicillin), resistance to ofloxacin, and cephalexin isolates sk4-3a and sk4-15. The examined isolates have shown a broad inhibitory spectrum against pathogens.

The purpose of this research paper was the evaluation of the safety aspects and probiotic potential of six isolates from the genus Enterococcus isolated from traditionally made cheese. The isolates represented part of the unexplored microflora of the cheese. The tolerance of Enterococcus isolates to different gastrointestinal conditions (low pH, the presence of pepsin, pancreatin and bile salts) were investigated. Using the microdilution method, sensitivity to clinically relevant antimicrobial agents (tetracycline, ampicillin, gentamicin, vancomycin and polymyxin B) was evaluated. The adhesion ability of autochthonous Enterococcus isolates to solvents, as well as the ability of auto- aggregation and co-aggregation between them and Escherichia coli clinical isolates, was investigated. The results indicated that isolates showed tolerance to the simulated gastrointestinal condition in a high percentage. Isolates were sensitive to all the tested antibiotics, especially to ampicillin, with MIC values obtained from 0.19-2.5 μg/mL. The isolates showed the ability of growth in medium with phenol and showed no ability to synthesize histamine and tyramine. The highest percentage of adhesion was detected with chloroform, and the lowest with xylene. The isolates showed moderate auto-aggregation ability, while a different degree of co-aggregation with E. coli was observed. The results indicated that the potential application of investigated Enterococcus isolates is selective and limited., Cilj ovoga rada bio je procjena sigurnosnog aspekta i probiotičkog potencijala šest izolata roda Enterococcus izoliranih iz tradicionalno rađenog sira. Izolati su predstavljali dio neistražene mikroflore sira. Analizirana je tolerancija izolata Enterococcus na različite gastrointestinalne uvjete (nizak pH, prisutnost pepsina, pankreatina i soli žučnih kiselina). Mikrodilucijskom metodom procijenjena je osjetljivost na klinički relevantne antimikrobne agense (tetraciklin, ampicilin, gentamicin, vankomicin i polimiksin B). Istraživana je i adhezivna sposobnost autohtonih izolata Enterococcus na otapala, kao i sposobnost autoagregacije i koagregacije između njih i kliničkih izolata Escherichia coli. Izolati su pokazali toleranciju na simulirane gastrointestinalne uvjete u velikom postotku. Utvrđena je osjetljivost na sve testirane antibiotike, posebno na ampicilin, s MIC vrijednostima od 0,19 do 2,5 μg/mL. Izolati su pokazali sposobnost rasta na hranjivoj podlozi s fenolom, a nisu pokazali sposobnost sintetizacije histamina i tiramina. Otkriveno je da je najveći postotak adhezije s kloroformom, a najmanji sa ksilenom. Izolati su pokazali umjerenu sposobnost autoagregacije, a opažen je i različit stupanj koagregacije s E. coli. Rezultati pokazuju da je potencijalna primjena istraživanih izolata bakterije Enterococcus selektivna i ograničena.

Enterobacter gergoviae KGPMF 20 was found in traditionally made cheese from Sokobanja (South-eastern Serbia). In this paper, the characteristics of the species were evaluated by investigation of adhesion to different solvents and co-aggregation ability with other species. Moreover, its enzymatic activity was evaluated by using spectrophotometric method, with the intention to detect the role of the isolate in the sensory characteristic of cheese. The results of enzymatic activity indicated that E. gergoviae KGPMF 20 has low, almost no enzymatic activity. It could be concluded that this isolate did not affect the sensory characteristic of cheese

This study monitors the influence of basic automotive paints on plankton and biofilms of selected microorganisms isolated from the wastewater of an automotive factory. Minimum Biofilm Eradication Concentration-High Throughput Plates system was used for the simultaneous tolerance testing. Minimal inhibitory concentration and minimal lethal concentration of the tested substances were determined for both planktonic cells and their biofilms. The resistance level of biofilms was also tested in standard 96 microtiter plates, whereby the results for bacteria and yeasts were confirmed by the fluorescence microscopy. The results were mutually compared for both plankton and biofilms, as well as for plankton and biofilm of the same microorganisms. In no case, the resistance of the planktonic form was higher than the biofilm for the same microorganism. Saccharomyces cerevisiae PMFKG-F7 in the presence of basic color, as well as Rhodotorula mucilaginosa PMFKG-F8 in the presence of the thinner for rinsing paint, shows high sensitivity in planktonic form, whereby the same species are the most resistant in the form of biofilm for the same substances. The highest resistance to all test substances was shown by the biofilm of R. mucilaginosa PMFKG-F8, as well as Candida utilis PMFKG-F9 which was significantly resistant in both tested forms. The obtained results suggest that autochthonous microorganisms that form biofilms can significantly improve the process of removing car paints from the wastewater and being thus new grounds for the development of new biotechnologies.

The five coumarin derivatives 3-(1-(2-hydroxypropylamino)ethylidene)-chroman-2,4-dione (L1), 3-(1-(phenylamino)ethylidene)-chroman-2,4-dione (L2), 3-(1-(o-toluidino)ethylidene)-chroman-2,4-dione (L3), 3-(1-(m-toluidino)ethylidene)-chroman-2,4-dione (L4), 3-(1-(2-mercaptoethylamino)ethylidene)-chroman-2,4-dione (L5) and its corresponding complexes 3-(1-(2-hydroxypropylamino)-ethylidene)-chroman-2,4-dione-palladium(II) (C1), 3-(1-(phenylamino)-ethylidene)-chroman-2,4-dione-palladium(II) (C2), 3-(1-(o-toluidino)-ethylidene)-chroman-2,4-dione-palladium(II) (C3), 3-(1-(m-toluidino)ethylidene)-chroman-2,4-dione-palladium(II) (C4), 3-(1-(2-mercaptoethylamino)ethylidene)-chroman-2,4-dione-palladium(II) (C5), were synthesized and characterized with microanalysis, infrared, 1H and 13C NMR spectroscopy. The proposed structures of ligands L3 and L4 were confirmed on the basis of the X-ray structural study. The ligands and their complexes were tested for their in vitro antimicrobial activity against 17 species of bacteria and fungi. Testing is performed by the microdilution method, with the minimum inhibitory concentration (MIC) and the minimum microbicidal concentration (MMC) being determined.

In this study, the effects of different temperature, pH, salt and glucose concentrations on the planktonic growth, biofilm formation, and formed biofilm of Serratia odorifera and Serratia marcescens, isolated from traditionally made cheese, were investigated using spectrophotometric method. The investigated strains demonstrated best planktonic growth and biofilm formation in Tryptic soy broth. The limiting factors for the planktonic growth and biofilm formation were temperature below 4 °C and salt concentration above 4%. Temperature of 37 °C and 44 °C, as well as various concentrations of glucose, stimulated the planktonic growth of bacteria. Moderate influence on biofilm formation was demonstrated at 37 °C as well as at various concentrations of glucose. These results were in accordance with the origin of bacteria, since the isolates were obtained from cheese.

In this study, the effects of different temperature, pH, different concentrations of salt, glucose and lactose, on the planktonic growth, biofilm formation and formed biofilm of Enterococcus hirae KGPMF9, Streptococcus uberis KGPMF2, Lactococcus lactis subsp. lactis KGPMF23 and Lactobacillus fermentum KGPMF29 was investigated. These lactic acid bacteria were previously isolated from traditionally made cheese from Southeastern Serbia. Evaluation of the effect of different environmental conditions on the planktonic growth, biofilm formation and formed biofilm were determined by spectrophotometric method. The limiting factor for the planktonic growth of tested bacteria was the salt concentration above 6.5%, while temperature of 4 °C was limiting factor for planktonic growth and biofilm formation. Temperature of 37 °C as well as various concentrations of glucose and lactose, stimulated planktonic growth and biofilm formation of all tested bacteria, except E. hirae KGPMF9. S. uberis KGPMF2 showed no ability of biofilm formation. Tested bacteria showed better planktonic growth and ability of biofilm formation in acidic media. Basic media was limiting factor for biofim formation. These results provide a basis for further research of influence of more environmental conditions on the development of lactic acid bacteria and their use like probiotics or starter cultures.

The biological activities of two binuclear copper(II) complexes containing S-alkenyl derivatives of thiosalicylic acid are reported [alkenyl = propenyl (L1), isobutenyl (L2)]. The structure of the complex with the S-isobutenyl derivative (C2) was confirmed by single-crystal X-ray structure analysis, which revealed that the structure consists of centrosymmetric, dinuclear complex molecules [Cu-2(S-i-butenyl-thiosal)(4)(DMSO)(2)] containing two Cu(II) centers bridged by four S-isobutyl-thiosalicylate ligands in a paddle-wheel type structure. The Cu(II) atom is situated in a distorted square-pyramidal environment formed by carboxylate oxygen atoms in the basal plane and a DMSO ligand in the axial position. The reactivities of the complexes toward guanosine-5-monophosphate (5-GMP) were investigated. Complex C2 ([Cu-2(S-i-butenyl-thiosal)(4)(H2O)(2)]) reacted more rapidly with 5-GMP than complex C1. The interactions of complexes C1 and C2 with calf thymus DNA (CT-DNA) were examined by absorption (UV-Vis) and emission spectral studies (ethidium bromide displacement studies), revealing good DNA interaction abilities. The antimicrobial activities of the free ligands and their complexes were tested by microdilution method, and both minimal inhibitory and microbicidal concentrations were determined. All the tested substances demonstrated selective and moderate antibacterial activity on gram-positive bacteria, but low antibacterial activity on gram-negative bacteria. Also, the tested substances demonstrated low antifungal activity.

In this study, the effects of environmental factors (different media, temperature, pH, salt and sugar concentrations) on the planktonic growth, biofilm formation and formed biofilm of Escherichia coli KGPMF 16 and Escherichia coli KGPMF 17 were investigated. Tested bacteria were isolated from traditionally made cheese produced in Southeastern Serbia (Sokobanja region). The influence on planktonic growth, biofilm formation and formed biofilm was determined using spectrophotometric method. The limiting factors for the planktonic growth and biofilm formation were temperature of 4 °C and all tested concentrations of salt. The growth of tested bacteria was higher in media enriched with lactose than in media containing glucose. TSB was more congenial media to the planktonic growth of bacteria than MHB broth. None of the tested bacteria demonstrated the ability to form biofilm at 4 °C and 44 °C. Only E. coli KGPMF 17 showed ability to form biofilm in TSB at 37 °C. Different concentrations of salt, glucose and lactose exhibited inhibitory effect on biofilm formation, but all tested concentrations of lactose showed stimulating effect on formed biofilm of E. coli KGPMF 17. These results contribute to better understanding of the effects of environmental factors on the development of E. coli in cheese.

The aim of the study was to examine heavy metal tolerance (Cd2+, Zn2+, Ni2+ and Cu2+) of single- and mixed-species biofilms (Rhodotorula mucilaginosa and Escherichia coli) and to determine metal removal efficiency (Cd2+, Zn2+, Ni2+, Cu2+, Pb2+ and Hg2+). Metal tolerance was quantified by crystal violet assay and results were confirmed by fluorescence microscopy. Metal removal efficiency was determined by batch biosorption assay. The tolerance of the mixed-species biofilm was higher than the single-species biofilms. Single- and mixed-species biofilms showed the highest sensitivity in the presence of Cu2+ (E. coli-MIC 4 mg/ml, R. mucilaginosa-MIC 8 mg/ml, R. mucilaginosa/E. coli-MIC 64 mg/ml), while the highest tolerance was observed in the presence of Zn2+ (E. coli-MIC 80 mg/ml, R. mucilaginosa-MIC 161 mg/ml, R. mucilaginosa-E. coli-MIC 322 mg/ml). The mixed-species biofilm exhibited better efficiency in removal of all tested metals than single-species biofilms. The highest efficiency in Cd2+ removal was shown by the E. coli biofilm (94.85%) and R. mucilaginosa biofilm (97.85%), individually. The highest efficiency in Cu2+ (99.88%), Zn2+ (99.26%) and Pb2+ (99.52%) removal was shown by the mixed-species biofilm. Metal removal efficiency was in the range of 81.56%–97.85% for the single- and 94.99%–99.88% for the mixed-species biofilm.

The objectives of this research project were isolation, identification, and evaluation of the safety aspect and probiotics properties of 21 Enterococcus faecium strains isolated from sausages originated from southeastern Serbia. Analyzed E. faecium isolates showed tolerance to simulated gastrointestinal conditions. All the examined isolates grew well on media with 0.1% and 0.2% of phenol. None of the tested isolates were histamine-producers, while the synthesis of tyramine was observed for E. faecium sk8-1 and sk8-17. Full resistance to antibiotics was not observed for any examined isolate of E. faecium (penicillin, amoxicillin, and ofloxacin showed the effect on all tested isolates). An inhibition zone against examined pathogens was exhibited by all strains, with the largest inhibition zone against Pseudomonas spp., Proteus spp. and E. coli (12–30 mm/MIC values ranged from 0.5 to 12 mg mL−1). The results indicated that E. faecium isolates from spontaneously fermented sausage showed a potential for further investigation and possible application as probiotics.

The objective of this study was to evaluate the probiotic potential as well as the ability of adhesion and aggregation of natural and autochthonous lactic acid bacteria, isolated from traditionally made cheese. Lactic acid bacteria from natural food sources can be promising probiotic candidates and they can be used in natural food preservation or like starter cultures. Tested autochthonous isolates showed tolerance to the simulated gastrointestinal condition as well as the sensitivity to clinically relevant antibiotics, especially to ampicillin (MIC at 0.195 μg mL−1 for lactobacilli and from 0.195 to 3.125 μg mL−1 for lactococci). Among isolates, the highest percentage of adhesion was detected with chloroform, while the adhesion ability of selected isolates to pig intestinal epithelium was in the correlation with the results of adhesion ability with solvents. The auto-aggregation ability of isolates was demonstrated, while co-aggregation with Escherichia coli was strain specific. The results indicated the potential probiotic properties of the isolates and give evidence for further investigation and potential application in the dairy industry.

Starting from well-defined NH2(CH3)2[PdCl2(XQ)] complexes, coordination compounds of general formula Cat[PdCl2(XQ)] have been prepared by cationic exchange of NH2(CH3)2+ and Cat cations, where XQ are biologically active halogen derivatives of quinolin-8-ol (5-chloro-7-iodo-quinolin-8-ol (CQ), 5,7-dibromo-quinolin-8-ol (dBrQ) and 5,7-dichloro-quinolin-8-ol (dClQ)) and Cat is K+ or Cs+. The cation exchange of all prepared complexes, K[PdCl2(CQ)] (1), K[PdCl2(dClQ)] (2), K[PdCl2(dBrQ)] (3), Cs[PdCl2(CQ)] (4), Cs[PdCl2(dClQ)] (5) and Cs[PdCl2(dBrQ)] (6) was approved using IR spectroscopy, their structures in DMSO solution were elucidated by one- and two-dimensional NMR experiments, whereas their stability in solution was verified by UV-VIS spectroscopy. Interaction of complexes to ctDNA was investigated using UV-VIS and fluorescence emission spectroscopy. The minimum inhibitory concentration and the minimum microbicidal concentration values were detected against 15 bacterial strains and 4 yeast strains to examine the antimicrobial activity for the complexes. The in vitro antitumor properties of the complexes were studied by testing the complexes on leukemic cell line L1210, ovarian cancer cell line A2780 and non-cancerous cell line HEK293. The majority of the prepared compounds exhibited moderate antimicrobial and very high cytotoxic activity.

The influence of 5 new Platinum(IV) (Pt(IV)) complexes with S-alkyl derivatives of thiosalicylic acid (C1-benzyl, C2-methyl, C3-ethyl, C4-propyl and C5- butyl) was studied on 16 strains of bacteria. Antibacterial activity was tested using microdilution method with resazurin while antibiofilm activity was observed by tissue culture plate method, using doxycycline as a positive control. The results were expressed as minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and biofilm inhibitory concentration (BIC). The best result on Gram positive bacteria exhibited C1 and MIC was

The spectroscopically predicted structure of the obtained copper(II)-complex with S-propyl derivative of thiosalicylic acid was confirmed by X-ray structural study. The binuclear copper(II)-complex with S-propyl derivative of thiosalicylic acid crystallized in two polymorphic forms with main structural difference in the orientation of phenyl rings relative to corresponding carboxylate groups. The antibacterial activity was tested determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) by using microdilution method. The influence on bacterial biofilm formation was determined by tissue culture plate method. In general, the copper(II)-complexes manifested a selective and moderate activity. The most sensitive bacteria to the effects of Cu(II)-complexes was a clinical isolate of Pseudomonas aeruginosa. For this bacteria MIC and biofilm inhibitory concentration (BIC) values for all tested complexes were in the range or better than the positive control, doxycycline. Also, for the established biofilm of clinical isolate Staphylococcus aureus, BIC values for the copper(II)-complex with S-ethyl derivative of thiosalicylic acid, [Cu-2(S-et-thiosal)(4)(H2O)(2)] (C3) and copper(II)-complex with S-butyl derivative of thiosalicylic acid, [Cu-2(S-bu-thiosal)(4)(H2O)(2)] (C5) were in range or better than the positive control. All the complexes acted better against Gram-positive bacteria (Staphylococcus aureus and Staphylococcus aureus ATCC 25923) than Gram-negative bacteria (Proteus mirabilis ATCC 12453, Pseudomonas aeruginosa, and P. aeruginosa. ATCC 27855). The complexes showed weak antioxidative properties tested by two methods (1,1-diphenyl-2-picrylhydrazyl (DPPH) and reducing power assay). (C) 2016 Elsevier B.V. All rights reserved.

Negative effects of available antibiotics and the constant development of bacterial resistance motivate a search for new antimicrobial agents. Aromatics plants have traditionally been used as antibacterial agents and are well accepted today as a source of antioxidants. The present study evaluated the antibacterial activities and antioxidant capacity of eight aromatic plants, indigenous to the flora of the Balkan Peninsula, which are used as medicinal plants in traditional medicine. The plants studied were Hyssopus officinalis , Angelica pancicii, Angelica sylvestris, Laserpitium latifolium , Achillea grandifolia, Achillea crithmifolia, Artemisia absinthium and Tanacetum parthenium . The antimicrobial activities of methanolic extracts of the plant tissues against 16 bacterial isolates of Escherichia coli , Pseudomonas aeruginosa , Klebsiella sp. , Proteus mirabilis , Acinetobacter sp. , Staphylococcus aureus , Streptococcus pyogenes , Streptococcus pneumoniae and Enterococcus faecalis were investigated using a microwell dilution assay. Minimal inhibitory concentration (MIC) of the extracts ranged from 6.3 to 100 mg mL -1 , and minimal bactericidal concentration (MBC) ranged from 12.5 to 100 mg mL -1 . Antioxidant potential of the extracts was analyzed as contents of total phenols and flavonoids; radical scavenging activity by the ABTS + and DPPH methods, and reducing power by the iron (III) to iron (II) reduction assay, and the ferric reducing antioxidant power assay (FRAP). Results of antioxidative activities from the 4 methods demonstrated similar sequence of activity: A. crithmifolia > A. grandifolia > H. officinalis > A. absinthium > T. parthenium > L. latifolium > A. pancicii > A. sylvestris. The total content of polyphenols and flavonoids in the methanol extracts of the studied species positively correlated with their antioxidant properties, confirming their major role in antioxidant activity of these species.

In this study, we determined the concentration of total phenols, flavonoids, tannins, and proanthocyanidins in the water, diethyl ether, acetone, and ethanol extracts of Agrimonia eupatoria L. We also investigated the antioxidant activity of these extracts using two methods [2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power] and their in vitro antimicrobial (antibacterial and antifungal) activity on some selected species of bacteria and fungi. In addition, the effects of the acetone and water extracts on the inhibition of biofilm formation of Proteus mirabilis and Pseudomonas aeruginosa were investigated using the crystal violet method. The concentration of total phenols was measured according to the Folin–Ciocalteu method and the values obtained ranged from 19.61 mgGA/g to 220.31 mgGA/g. The concentration of flavonoids was examined by the aluminum chloride method and the values obtained ranged from 20.58 mgRU/g to 97.06 mgRU/g. The total tannins concentration was measured by the polyvinylpolypyrrolidone method and the values obtained ranged from 3.06 mgGA/g to 207.27 mgGA/g. The concentration of proanthocyanidins was determined by the butanol–HCl method and the values obtained ranged from 4.15 CChE/g to 103.72 CChE/g. Among the various extracts studied, the acetone extract exhibited good antioxidant activity (97.13%, as determined by the DPPH method). The acetone extract was active in the absorbance value range from 2.2665 to 0.2495 (as determined by the reducing power method). The strongest antimicrobial activity was detected on G + bacteria, especially on probiotic species, and the acetone extract demonstrated the highest activity. Biofilm inhibitory concentration required to reduce biofilm coverage by 50% values for acetone extract was 4315 μg/mL for P. mirabilis and 4469.5 μg/mL for P. aeruginosa. The results provide a basis for further research of this plant species.

Four new platinum(IV) complexes C1–C4 of general formula [PtBr4(R2-S,S-eddv)], (R = ethyl, propyl, butyl and pentyl; S,S-eddv = (S,S)--ethylenediamine-N,N′-di-2-(3-methyl)butanoate) have been synthesized and characterized by microanalysis, infrared, 1H and 13C NMR spectroscopy. In vitro antimicrobial activity for these and [PtBr4(R2-S,S-eddp)] complexes (S,S-eddp = (S,S)-ethylenediamine-N,N′-di-2-propanoate) has been investigated. The antibacterial activity was tested against 16 strains of bacteria determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) using microdilution method. In general, platinum(IV) complexes manifested moderate activity against the Gram positive bacteria and low activity against the Gram negative bacteria. The complexes showed weak antioxidative properties tested by two methods (DPPH and reducing power assay).

A series of four new ligands of general formula R2-S,S-eddtrp·2HCl (L1–L4) and their palladium(II) complexes of general formula [PdCl2(R2-S,S-eddtrp)] (C1–C4) where R = ethyl, 1-propyl, 1-butyl and 1-pentyl; S,S-eddtrp·2HCl = ethylenediamine-N,N′-di-(3,3′-1H-indol-3yl)propionic acid dihydrochloride have been synthesized and characterized by elemental microanalysis, infrared, 1H and 13C NMR spectroscopy. The proposed structures of all compounds were examined by density functional theory (DFT). The ligands (L1–L4) and Pd(II) complexes (C1–C4) were screened for their antimicrobial activity against 19 microorganisms and minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) were determinated. All tested ligands and complexes exhibited the highest antimicrobial activity on Escherichia coli ATCC 25922, being in range or higher than positive control, tetracycline.

In this study, inhibitory effects of crude silk produced by 5th larval instar of moth Plodia interpunctella , as well as ethanol, acetone, ethyl acetate, hexane and dichloromethane silk extracts were evaluated against 18 bacterial strains (ATCC strains/isolates) and 6 fun-gal ATCC strains in vitro . Among the tested extracts, the acetone silk extract had the highest activity against Gram-negative bacteria,while all the extracts showed moderate to high activity against Gram-positive bacteria and fungi. The dilution of 1/2, 1/4 of stock samples showed higher microbial activity. The crude silk was not bioactive. This is the first report on antimicrobial activity of different extracts of silk of P. interpunctella larvae. These results open new ave-nues for future research in using this major storage insect pest in biomedical applications.

In the present manuscript, palladium(II) complexes (C1, C2) with newly synthesized coumarine ligands 3-(1-((3-chlorophenyl)amino)ethylidene)-chroman-2,4-dione (L1) and 3-(1-((4-chlorophenyl)amino)ethylidene)-chroman-2,4-dione (L2) were prepared and structurally characterized by spectroscopic techniques (FT-IR, 1H NMR, 13C NMR) in combination with elemental analysis and theoretical methods (DFT). The structures of all compounds were fully optimized using the B3LYP-D3BJ theoretical method. Cytotoxic activity of investigated compounds was tested against two cells lines (human colorectal carcinoma, HCT-116, and human fibroblast lung MRC-5), while their antimicrobial activity was screened against nine strains of pathogenic bacteria, five mould species and two yeast species. Unfortunately, their cytotoxic and antibacterial activities were weak. Docking studies for all compounds with epidermal growth factor receptor (EGFR) were performed. It was found that hydrophobic interactions that include chlorine atom have somewhat lower values of the pairwise interaction energies compared to the purely hydrophobic interactions. In addition, it was found the chlorine atom in the para position contributes to the slightly higher binding free energy and lower values of constant of inhibition.

A series of new 3d metal complexes with 5-chloro-quinolin-8-ol (ClQ), [Mn(ClQ)2] (1), [Fe(ClQ)3] (2), [Co(ClQ)2(H2O)2] (3), [Ni(ClQ)2(H2O)2] (4), [Cu(ClQ)2] (5), [Zn(ClQ)2(H2O)2] (6), [Mn(ClQ)3]·DMF (7) and [Co(ClQ)3]·DMF·(EtOH)0.35 (8) (DMF=N,N-dimethylformamide), has been synthesized and characterized by elemental analysis, IR spectroscopy and TG-DTA thermal analysis. X-ray structure analysis of 7 and 8 revealed that these molecular complexes contain three chelate ClQ molecules coordinated to the central atoms in a deformed octahedral geometry and free space between the complex units is filled by solvated DMF and ethanol molecules. Antimicrobial activity of 1-6 was tested by determining the minimum inhibitory concentration and minimum microbicidal concentration against 12 strains of bacteria and 5 strains of fungi. The intensity of antimicrobial action varies depending on the group of microorganism and can be sorted: 1>ClQ>6>3/4>2>5. Complexes 1-6 exhibit high cytotoxic activity against MDA-MB, HCT-116 and A549 cancer cell lines. Among them, complex 2 is significantly more cytotoxic against MDA-MB cells than cisplatin at all tested concentrations and is not cytotoxic against control mesenchymal stem cells indicating that this complex seems to be a good candidate for future pharmacological evaluation. Interaction of 1-6 with DNA was investigated using UV-VIS spectroscopy, fluorescence spectroscopy and agarose gel electrophoresis. The binding studies indicate that 1-6 can interact with CT-DNA through intercalation; complex 2 has the highest binding affinity. Moreover, complexes 1-6 inhibit the catalytic activity of topoisomerase I.

The aim of this study was to examine heavy metal tolerance (lead (Pb2+) and mercury (Hg2+)) of single- and mixed-species biofilms, formed by yeast Rhodotorula mucilaginosa and bacteria Escherichia coli LM1. Single- and mixed-species biofilms were quantified by crystal violet test and the absorbance was measured using microplate reader (OD570). The minimal inhibitory concentration (MIC) and the minimal lethal concentration (MLC) were determined and the results were confirmed by fluorescence microscopy. The significant difference in lead tolerance was observed between the mixed- and the single-species biofilms. The MIC of lead (Pb2+) for the examined biofilms (E. coli LM1, R. mucilaginosa and R. mucilaginosa / E. coli) was recorded at concentrations of 4000 μg/ml, 4000 μg/ml and 16000 μg/ml, respectively. The MIC of mercury (Hg2+) for the biofilms was noticed at concentrations of 31.25 μg/ml, 250 μg/ml and 250 μg/ml, respectively. Standard antibiotics (amphotericin B and tetracycline) were used as positive control. Results obtained for single-species biofilms were compared in between and with the results obtained for mixed-species biofilm. The tolerance of the mixed- species biofilm was higher in comparison to the singlespecies biofilms and the results were confirmed by a fluoresecence microscope. The obtained results suggest that the R. mucilaginosa / E. coli biofilm may have a potential to be used in bioremediation of wastewaters contaminated with lead and mercury.

The aim of study was to investigate the antimicrobial and antibiofilm activities as well as chemical analysis of aquatic, acetone and ethyl acetate extracts Vinca minor L. collected in Balkan mountains (Dinaric Alps, Serbia). Antimicrobial testing was performed by microdilution method. Minimum inhibitory concentration and minimal microbicidal concentration were determined for 26 species of microorganisms. Strong antimicrobial activity was detected against Gram-positive bacteria, especially from genus Bacillus. Gramnegative bacteria were not sensitive within the tested extracts concentrations. Ethyl acetate extract from V. minor caused some antifungal effect on Rhodotorula and Candida. Trichoderma viride was sensitive to aquatic extract of the plant. Antibiofilm activity was tested by crystal violet assay. Only ethyl acetate extract was effective against formation of biofilm by Proteus mirabilis and biofilm inhibitory concentration (BIC50) was at 22.8 mg/mL. Phytochemical analysis involved determining the amount of total phenols, flavonoids and tannins as well as antioxidant activity monitoring capability to neutralize 2.2-diphenyl-1-picrylhydrazyl (DPPH) free radicals and reduction potential. Total phenolic content, DPPH and reduction potential of the aquatic extract of V. minor was significantly stronger compared to the acetone and ethyl acetate extracts.

Ethnopharmacological relevance: Trapa natans L. (water chestnut or water caltrop) is a widespread aquatic plant, which has been cultivated for food and traditional medicine since ancient times. Pharmacological studies showed that water chestnut exhibits the wide range of biological activities, such as antimicrobial, antioxidative, analgesic, anti-inflammatory, as well as antiulcer. Aim of the study: Evaluation of anti-virulence potential and toxicity of T. natans methanol (TnM), acetone (TnA) and ethyl acetate (TnEA) leaf extracts. Materials and methods: The anti-quorum sensing activity of Tn extracts was addressed by measuring their effects on biofilm formation, swarming motility and pyocyanin and elastase production in Pseudomonas aeruginosa. Specific P. aeruginosa biosensors were used to identify which of the signaling pathways were affected. The lethal and developmental toxicity of extracts were addressed in vivo using the zebrafish (Danio rerio) model system. The phenolic composition of T. natans leafs extracts was analyzed by a linear ion trap-OrbiTrap hybrid mass spectrometer (LTQ OrbiTrapMS) and UHPLC system configured with a diode array detector (DAD) hyphenated with the triple quadrupole mass spectrometer. Results: Subinhibitory concentrations of Tn leaf extracts (0.2 MIC) inhibited pyocyanin and elastase production up to 50% and 60%, respectively, and reduced swarming zones, comparing to non-treated P. aeruginosa. TnA inhibited biofilm formation by 15%, TnM showed a stimulatory effect on biofilm formation up to 20%, while TnEA showed no effect. The bioactive concentrations of TnM and TnA were not toxic in the zebrafish model system. Twenty-two phenolic compounds were tentatively identified in TnM, where thirteen of them were identified in T. natans for the first time. Tn extracts, as well as their major components, ellagic and ferulic acids, demonstrated the ability to interfere with P. aeruginosa Las and PQS signaling pathways. Conclusions: This study demonstrates anti-virulence potential of Tn leaf extracts against medically important pathogen P. aeruginosa and confirms the ethnopharmacological application of this plant against microbial infections. This is the peer-reviewed version of the following article: Aleksic, I.; Ristivojevic, P.; Pavic, A.; Radojević, I.; Čomić, L. R.; Vasiljevic, B.; Opsenica, D.; Milojković-Opsenica, D.; Senerovic, L. Anti-Quorum Sensing Activity, Toxicity in Zebrafish (Danio Rerio) Embryos and Phytochemical Characterization of Trapa Natans Leaf Extracts. Journal of Ethnopharmacology 2018, 222, 148–158. [https://doi.org/10.1016/j.jep.2018.05.005] Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/2933]

Streptococcus uberis is an environmental bacterium responsible for bovine mastitis. It is occasionally described as a human pathogen. In our study, the isolation was undertaken of lactic acid bacteria from a local cheese from Southeastern Serbia, produced in a traditional way. S. uberis (7 isolates) and S. agalactiae (1 isolate) were isolated from the cheese samples taken in the summer. The biochemical and physiological characteristics of the isolates were examined. Using tetracycline, chloramphenicol, novobiocin and rifampicin, the antibiotic susceptibility of the isolates was evaluated. The results demonstrated that all the isolates were susceptible to all the tested antibiotics, with a growth inhibition zone from 36-48 mm. Also, the antagonism was examined of S. uberis KGPMF1-7 and S. agalactiae KFPMF8 isolates on the growth of Escherichia coli ATCC 25922, Proteus mirabilis ATCC 12453, Klebsiella oxytoca KGPMF1, Klebsiella ornithinolytica KGPMF8 and Aeromonas hydrophila, as indicator stains. The results were compared with the activities of chloramphenicol, streptomycin and tetracycline on the tested indicator stains. The strongest antagonism was demonstrated by all Streptococcus isolates on the growth of K. oxytoca KGPMF1 (growth inhibition zone from 12-20 mm) and the A. hydrophila (growth inhibition zone from 13-20 mm). When these results were compared with the results of the sensitivity of tested indicator stains to antibiotics, S. uberis KGPMF1-7 and S. agalactiae KGPMF8 isolates showed a moderate antagonistic effect. Due to the specific way cheese is made in from Sokobanja, these isolates probably originate from cows’ udders., Streptococcus uberis jest okolišna bakterija odgovorna za mastitis kod goveda, a povremeno se opisuje kao patogen u ljudi. U ovom su istraživanju izolirane bakterije mliječne kiseline iz autohtonog sira jugoistočne Srbije, proizvedenog na tradicionalni način. S. uberis (7 izolata) i S. agalactiae (1 izolat) izolirani su iz uzoraka sira prikupljenih tijekom ljeta. Analizirane su biokemijske i fiziološke značajke izolata. Koristeći se tetraciklinom, kloramfenikolom, novobiocinom i rifampicinom, procijenjena je osjetljivost izolata na antibiotike. Rezultati su pokazali da su svi izolati osjetljivi na sve istražene antibiotike, sa zonom inhibicije rasta od 36 do 48 mm. Također, istražen je antagonizam S. uberis KGPMF1-7 i S. agalactiae KFPMF8 izolata na rast Escherichia coli ATCC 25922, Proteus mirabilis ATCC 12453, Klebsiella oxytoca KGPMF1, Klebsiella ornithinolytica KGPMF8 i Aeromonas hydrophila kao indikatorskih sojeva. Rezultati su uspoređeni s aktivnostima kloramfenikola, streptomicina i tetraciklina na testiranim indikatorskim sojevima. Najjači antagonizam pokazali su svi Streptococcus izolati na rast K. oxytoca KGPMF1 (zona inhibicije rasta od 12 do 20 mm) i A. hydrophila (zona inhibicije rasta od 13 do 20 mm). Usporedbom tih rezultata s rezultatima osjetljivosti istraženih indikatorskih sojeva na antibiotike, za S. uberis KGPMF1-7 i S. agalactiae KGPMF8 izolate utvrđen je umjeren antagonistički učinak. Ti izolati vjerojatno potječu iz vimena krava i u siru iz Sokobanje prisutni su zbog specifičnosti njegove pripreme.

Management of water resources such as lakes and reservoirs involves many stakeholders and a huge amount of data that comes from various information systems and in different formats. These systems are typically very difficult to integrate, analyze and customize. This requires a new breed of information systems capable to answer the challenges of modern water information management. In this paper, we introduce the new application model for designing such systems and accompanying i-SeLaR software system - composite, service-oriented and multilayered web information system for management of Serbian lakes and reservoirs. We describe architecture and services of the application model, together with structure and functionalities of the software solution. i-SeLaR integrates data, tools and applications for collaboration, data and knowledge management, process automation, and analytics. Architecture and features of i-SeLaR provide scalability and flexibility, so the system can be scaled, customized and implemented in organizations of different types and sizes. i-SeLaR web portal is the central component which serves as a unique gateway to different data sources and services, and provides a seamless and unified web interface for monitoring and management of water resources. Practical results showed several benefits in terms of better integration and flexibility, enhanced collaboration, higher data quality, knowledge-based analysis and more informed decision making.

The antioxidant and antimicrobial activities and contents of total phenolics and flavonoids of Ajuga chamaepitys (L.) Schreb. subsp. chamaepitys (Lamiaceae) were investigated. Five different extracts from aboveground flowering plant parts were obtained by extraction with water, methanol, acetone, ethyl acetate and petroleum ether. The total phenolic content was determined spectrophotometrically using the Folin-Ciocalteu reagent and expressed as the gallic acid equivalent (mg GA/g of extract). The highest value was obtained in the ethyl acetate extract (57.02 mg GA/g). The concentration of flavonoids, determined using a spectrophotometric method with aluminum chloride and expressed as the rutin equivalent (mg RU/g of extract), was highest in the ethyl acetate extract (91.76 mg RU/g). The antioxidant activity was determined in vitro using 2,2-diphenyl-1-picrylhydrazyl (DPPH) reagent. The highest antioxidant activity was detected in the acetone extract (SC50 value = 330.52 μg/mL). In vitro antimicrobial activities were determined using a microdilution method, and the minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) were determined. The most effective antimicrobial activity against Bacillus cereus was demonstrated by the acetone extract, with MIC and MMC values of 1.25 mg/mL. Based on the results of this study, A. chamaepitys subsp. chamaepitys could be considered as a valuable source of natural compounds with important biological activities. [Projekat Ministarstva nauke Republike Srbije, br. III 41010 i OI 173032]

The octahedral cobalt(III) complexes with (S,S)-ethylenediamine-N,N-di-2-propionic (S,S-eddp) and (S,S)-ethylenediamine-N,N-di-2-(3-methyl)-butanoic (S,S-eddv) acids and oxalato and malonato ligands, as additional bidentate ligands, were prepared and characterized. The complexes were purified by ionexchange chromatography. The geometry of the complexes has been supposed on the basis of the infrared, electronic absorption and NMR spectra. The A absolute configurations of the isolated complexes have been predicted on the basis of their circular dichroism (CD) spectra and it was confirmed by single-crystal X-ray analysis of potassium-Delta-(-)(589)-s-cis-oxalato-(S,S)-ethylenediamine-N,N-di-(2-propanoato)-cobaltate(III)-semihydrate, K-Delta-(-)(589)-s-cis-[Co(S,S-eddp)(ox)]center dot 0.5H(2)O. Antimicrobial activity of ligands and obtained cobalt(III) complexes was evaluated by determining the minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) in relation to 13 species of microorganisms (five strains of pathogenic bacteria, five species pathogenic fungi and three species of probiotic). Tested ligands and complexes demonstrated moderate and low antibacterial and antifungal activity. There was no difference in activities between the ligands and complexes. (C) 2014 Elsevier Ltd. All rights reserved.

This study deals with synthesis of methyl cinnamate, butyl cinnamate, and p-methoxy methyl cinnamate and testing of their in vitro antimicrobial activity. Antimicrobial activity was examined towards 29 microorganisms using microdilution method. It is shown that antimicrobial activity of methyl cinnamate and p-methoxy methyl cinnamate was better than that of butyl cinnamate. Sarcina lutea, Bacillus subtilis ATCC 6633, B. subtilis and B. subtilis IP 5832 (probiotic) were the most sensitive bacteria. It is established that p-methoxy methyl cinnamate can be a new, potential anti-Staphylococcus aureus agent with minimum inhibitory concentration of 62.5 ?g/ml. Methyl cinnamate and p-methoxy methyl cinnamate inhibited the growth of Aspergillus restrictus, A. flavus and A. fumigatus in the concentration range from 62.5 ?g/ml to 250 ?g/ml.

In this paper, the presence of enterobacteria in autochthonous cheese from Southeast Serbia (Sokobanja), made in the traditional way, was investigated. The samples from different households, was taken during the summer and the autumn. Chemical and physical characteristics of samples (water content, fat content, acidity, pH, and sodium chloride content) were examined. In the analyzed samples of cheese, four different genera of family Enterobacteriaceae (Klebsiella [65%], Escherichia [20%], Serratia [10%], and Enterobacter [5%]) were identified. The members of genus Klebsiella were Klebsiella oxytoca, Klebsiella pneumoniae, and Klebsiella ornithinolytica, while in the genus Escherichia only one species, Escherichia coli was identified. Besides, two species of the genus Serratia, Serratia odorifera and Serratia marcescens biogp 1, and one species of the genus Enterobacter, Enterobacter gergoviae, were identified. Biochemical characteristics, proteolytic and lipolytic activity, sensitivity to streptomycin, chloramphenicol, and tetracycline were, also, determined. According to the rapid latex agglutination test, of the four E. coli isolates, two isolates belong to serotype E. coli O157. Practical applications The results of this study contribute to better understanding of unexplored microflora of cheese from Sokobanja. The isolated genera were Klebsiella sp., Escherichia sp., Enterobacter sp., and Serratia sp. with twenty identified species. It is well known that bacteria from family Enterobacteriaceae could affect organoleptic properties of cheese. Bacteria isolated from cheese from Sokobanja mostly did not manifest proteolytic and lipolytic activity. The most number of isolates were susceptible to tested antibiotics. Further researches may contribute to better understanding of interaction between enterobacteria and lactic acid bacteria in autochthonous cheeses.

The five new copper(II) complexes with some S-alkyl derivatives of thiosalicylic acid (alkyl = benzyl (L1), methyl (L2), ethyl (L3), propyl (L4), butyl (L5)) have been synthesized and characterized by microanalysis and infrared spectra. The spectroscopically predicted structure of the obtained binuclear copper(II) complex with S-methyl derivative of thiosalicylic acid was confirmed by X-ray analysis. Single crystals suitable for X-ray measurements were obtained by slow crystallization from a water solution. The compound crystallizes with two binuclear Cu(II) complex molecules in the asymmetric unit. Both molecules have typical paddle-wheel structure with apical positions occupied by water molecules. The independent molecules showed slight difference in configuration mainly reflected in the different orientation of the phenyl rings relating to their carboxylate groups. Antimicrobial activity of these complexes was tested by microdilution method and both minimal inhibitory and microbicidal concentration were determined. The intensity of the antimicrobial activity varied depending on the species of microorganism and the compound type. In general, the activity of the complexes was higher than or similar to the corresponding ligands. All the tested complexes demonstrated moderate or selective antibacterial activity and low antifungal activity. (C) 2014 Elsevier Ltd. All rights reserved.

Five 3d metal [M(H2O)2(SQ)]n complexes, where M is Mn (1), Co (2), Ni (3), Zn (4) and Cu (5), and SQ is the dianion of 8-hydroxyquinoline-5-sulfonic acid have been prepared and characterized by IR spectroscopy and elemental analysis. X-ray structure analysis of 1 and 5 in combination with IR spectroscopy of all five complexes showed that complexes 1–4 are isostructural 2D polymers, while 5 is 1D polymer due to the different bonding character of SQ. Stability of all complexes in DMSO was proved by UV–Vis spectroscopy and for 4 also verified by 1H and 13C NMR spectroscopy. Cytotoxic activity tests against cervical carcinoma HeLa, colon carcinoma HCT116 and normal human fibroblast MRC-5 cell lines showed moderate but selective cytotoxicity of all complexes. Complex 1 exhibited highest activity with IC50 = 39.1 and 33.4 µM, respectively, but is lower than activity of cisplatin (CP) which IC50 = 24.3 and 14.3 µM, respectively. However, their cytotoxic activity against healthy MRC-5 cells (IC50 > 92 µM) is much lower than CP (IC50 = 19.7 µM). Antimicrobial activity of all complexes against 9 strains of pathogenic bacteria, five mould species and two yeast species is negligible.

This research presents complete data about phytochemical analysis and biological activities of a new dietary supplement for commercial use “Oligo Grapes” (OG), and its individual constituents: lyophilized pomace (LP), clay supplemented with red wine extract, lyophilized pomace ethanolic extract (PE), and red wine extract. OG, as a commercially available food supplement, has not been previously tested for its biological activity. Now we want to present new data about its phytochemical screening, antioxidant and antibacterial activities, and anticancer properties with respect to its cytotoxicity and effects on redox status in colon cancer cell lines. The tested extracts expressed strong antibacterial activity against Proteus mirabilis and Proteus mirabilis ATCC 12453, where the synergy of contents inside the supplement demonstrated a higher influence on the bacteria than its separately tested constituents. Among the investigated extracts, PE, as the extract with the highest phenolics concentration, had remarkable cytotoxic activity on HCT-116 and SW-480 colon cancer cells. Also, the treatments modulated redox status in the investigated cancer cells, by inducing oxidative and nitrosative stress, which could be one of the preferred mechanisms of the anticancer action. Based on the achieved antimicrobial and anticancer properties, there is a need for producing different food supplements and nutritional products originating from grapes. In this respect, the food supplement OG and its health benefits deserve scientific attention and further research.

Antibacterial, antibiofilm and antioxidant activity of acetone, ethanol, ethyl acetate and diethyl ether extracts of P. nodosus Poir. were tested. In vitro antibacterial activity was investigated by microdilution method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) have been determined. The values were in the range from 5 to > 5 mg/ml. Antibiofilm activity was tested by crystal violet assay. The biofilm inhibitory concentration (BIC) values were from 2.03 to > 10 mg/ml. The best results against biofilm formation had ethanol and ethyl acetate extracts. The total phenolic content was established by using Folin-Ciocalteu method. The highest total phenol content was found in the ethyl acetate extract (28.45 mg GA/g) while the lowest content in the ethanol extract (22.74 mg GA/g). The concentrations of flavonoids were determined using aluminium chloride method. The concentration of total flavonoid content was 102.09 mg RU/g for the ethyl acetate extract, while the lowest content was noticed in diethyl ether extract (32.93 mg RU/g). The antioxidant activity was determined by the DPPH free radicals assay. Antioxidative efficiency was in the range from 641.77 to 8811.63 μg/ml. The tested extracts showed weak antioxidant activity (AAI < 0.5).

The antibacterial and anti-biofilm activity of ethanolic extract from the rhizome of Zingiber officinale were evaluated. In vitro antibacterial activity was investigated by microdilution method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) have been determined. The values were in the range from 0.0024 to > 20 mg/ml. The most sensitive bacteria were Gram-positive bacteria: Staphylococcus aureus and Staphylococcus aureus ATCC 25923. Anti-biofilm activity was tested by crystal violet assay. Pseudomonas aeruginosa ATCC 27853, Proteus mirabilis and Escherichia coli ATCC 25922 were used as the test organisms. Ethanolic extract showed the best result on Proteus mirabilis biofilm where biofilm inhibitory concentration (BIC50) was 19 mg/ml.

This study investigated the antimicrobial activity as well as some phytochemical analysis of ethanol and diethyl ether extracts from plant species Vinca minor L. In vitro antimicrobial activity of extracts was studied on 20 strains of microorganisms (16 bacteria and four yeasts). Testing was performed by microdilution method and minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) were determined. The strongest antimicrobial activity wa s detected on G+ bacteria of the genus Bacillus . Tested G - bacteria and yeasts were not sensitive to the acti on of the extracts or the sensitivity was insignificant. Phytochemical analysis involved determining the amount of total phenolics, flavonoids and tannins, as well as the determination of antioxidan t activity monitoring capability to neutralize free radicals (DPPH) and the reductive p otential. Phytochemical examination indicates that the total phenolic compounds were mo re in the ethanolic extract and the content of flavonoids and tannins marginally higher in the diethyl ether extract. The antioxidant activity (DPPH) of the ethanolic extrac t of V. minor was significantly stronger as compared to the diethyl ether extract, and the redu ction potential was approximately the same.

The s-cis -[Cr( S , S- eddv)L]-complexes ( 1 , 2 ) ( S , S -eddv = ( S , S )-ethylenediamine- N , N ′-di-2-(3 - methyl ) butanoato ion; L = oxalate or malonate ion) were prepared. The complexes were purified by ion-exchange chromatography. The geometry of the complexes has been supposed on the basis of the infrared and electronic absorption spectra, and the absolute configurations of the isolated s-cis -[Cr( S , S -eddv)L]-complexes have been predicted on the basis of their circular dichroism (CD) spectra. Also, the results of thermal decomposition have been discussed. Antimicrobial activity of the prepared complexes ( 1 – 4 ) was investigated against 28 species of microorganisms. Testing was performed by microdilution method and minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) have been determined. Complexes demonstrated in generally low antibacterial and antifungal activity.