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The paper examines the effect of the application of three different preparations on the presence of four economically significant diseases in the crops of pot marigold, valerian and potato. On pot marigold, the intensity was determined of pot marigold powdery mildew infection of the marigold leaf (Podosphaera xanthii (Castagne) U. Braun & Shishkoff), whereas on valerian, it was the intensity of valerian stem canker and black mold (Alternaria alternata (Fr. ex Fr.) Keissel), and in potatoes, the intensity of early blight (Alternaria solani (Ellis & Mart.)) and that of late blight (Phytophthora infestans (Mont.) de Bary). Of the preparations, the synthetic preparation "Sekvenca" ("Sequence") (a.m. difenoconazole, 250 g/l) was applied at a dose of 0.5 l/ha, the registered biostimulant "Zlatno inje" ("Golden frost") (manure-based fertiliser) was applied at a dose of 3.0 l/ha, microbiological preparation (Bacillus amyloliquefaciens ssp. TMF3) at a dose of 3.0 l/ha. The fourth variant was the control variant, i.e. the variant without treatment. Field experiments were performed during 2019 at two locations in the wider area of the City of Pančevo. The experiments were performed by a randomised block system with three replications. The size of the main plot was 9.0 m2 (4.5 x 2.0 m). The following was used as plant material: the pot marigold variety of "Domaći oranž" ("Domestic orange"), the valerian variety of "Vojvođanski" ("Vojvodinian") and the potato variety of "Desire". The first assessment of disease intensity was performed one month following the treatment with the selected preparations, and the second one was performed two weeks after the first assessment. In the pot marigold crops, the smallest infection percentage had the plants treated with the type Bacillus amyloliquefaciens TMF3, in valerian, the fewest plants infected with the fungus A. alternata were recorded on small plots on which the synthetic preparation "Sekvenca" was applied, which was also the case with early blight and late blight. The weakest efficiency in the control of pot marigold powdery mildew infection and valerian stem canker and black mold was recorded with the use of the biostimulant "Zlatno inje", which showed the highest efficiency in the case of late blight. The highest yield of pot marigold seeds (632.7 kg/ha) had been treated with the type Bacillus amyloliquefaciens TMF3, with valerian, the highest seeds yield was recorded following the application of the preparation "Sekvenca" (186.1 kg/ha), while in potatoes, the highest amount of tubers was recorded with the preparation "Zlatno inje" (30.83 t/ha). However, if the agroecological and the agrotechnical aspects of production are taken into account, by the use of the type Bacillus amyloliquefaciens TMF3, a satisfactory basis was achieved for various kinds of further research of this and similar preparations in order to improve the existing production of medicinal and other types of plants.

Fluorapatite nanopowders with different amounts of fluoride ions were prepared using the surfactant-assisted microwave method under isothermal conditions. Microwave irradiation was applied for the rapid formation of crystals. A micellar solution of polyoxyethylene (23) lauryl ether was used as a regulator of nucleation and crystal growth. Characterization studies from X-ray diffraction, field-emission scaning electron microscopy and Fourier-transform infrared spectra showed that crystals have an apatite structure and particles of all samples are nano size, with an average length of 50 nm and about 15-25 nm in diameter. Antimicrobial studies have demonstrated that synthesized fluorapatite nanopowders exhibit activity against tested pathogens: Escherichia coli, Staphylococcus aureus and Candida albicans. Activity increased with the amount of fluoride ions. The synthesized fluorapatite nanomaterials are promising as materials in environmental protection and medicine for orthopedics and dental restorations. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 43009]

A novel double layered hybrid materials, consisting of low density polyethylene (LDPE) base layer and polycaprolactone (PCL) top layer containing surface modified nanocellulose (NC) based nanocomposites in 0.5 and 2 % loadings, were studied in order to design multipurpose packaging material. NC was covalently modified with maleic anhydride (MA) to obtain NCMA, and upon co-precipitation of copper (II) oxide (CuO) on NC and NCMA surface, NC-CuO and NCMA-CuO nanocomposite materials were produced. Two drying methods, conventional and lyophilization, were applied to investigate process influences on the properties of obtained hybrid material. Oxygen transmission rate and antimicrobial activity were determined for all produced hybrid materials. PE-PCL-NCMA-CuO-L2 exhibited the highest antifungal properties, indicating contribution of MA residual group and drying conditions (liophylisation) to achievement of 97 % reduction in cell viability of C. albicans. The sample with 2 % of NCMA-CuO, PE-PCL-NCMA-CuO2, demonstrated to be the most promising material regarding improvement in antibacterial and antifugal activity, as well as 16 % lower value of the oxygen transmission rate in comparison to pure LDPE. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III45019]

The objective of our study was to develop new antimicrobial hydrogels silver/poly(2-hydroxyethyl methacrylate/ itaconic acid) (Ag/P(HEMA/IA)). The P(HEMA/IA) samples, with different HEMA/IA ratio, were prepared by free radical crosslinking copolymerization. Ag ion were introduced in hydrogels by immersing dried P(HEMA/IA) disks in silver(I) salt solution, which was confirmed by FTIR spectroscopy. The in vitro controlled release of silver(I) ion from (Ag/P(HEMA/IA)) gels, and antimicrobial activity during the release period were also studied. The release profiles have shown a two-phase exponential profile, with fast initial phase, followed by a much slower release rate. Kinetic parameters determined, have indicated Fickian transport of Ag(I) ion in the initial phase. It is perceived that the antimicrobial activity of the Ag/P(HEMA/IA) depends on IA content. Excellent antimicrobial potential was maintained during the entire release time.

In this study, twelve strains of Lactobacillus plantarum derived from spontaneously fermented vegetables (carrots and beetroot) and traditionally prepared sauerkraut were compared for their potential probiotic abilities with seven Lactobacillus rhamnosus strains of human origin. The tested strains were investigated for some technological properties and in vitro functional characteristics for potential probiotic strains. Selection probiotic criteria included the ability of the strains to withstand conditions similar to the digestive tract, antimicrobial activity against a wide range of intestinal pathogens and sensitivity to antibiotics. The total acidity in milk was generally higher in intestinal strains in relation to plant strains. The ability of the tested strains to survive simulated gastric conditions showed a greater resistance of the human strains at a low pH 2.5 and the presence of pepsin, while in the presence of bile salts and pancreatin, some intestinal strains were more sensitive compared to plant strains. A wide spectrum of antimicrobial activities was observed in all tested strains. Most of the plant strains were resistant to aminoglycosides and vancomycin but sensitive to ampicillin and penicillin, while only some intestinal strains were resistant to these drugs. [Projekat Ministarstva nauke Republike Srbije, br. 46010]

This study compares the effect of colloidal silver nanoparticles and commercial RUCO-BAC AGP agent with silver chloride as an active component on antibacterial activity of dyed cotton fabrics. Cotton fabrics were dyed with vat dyes Bezanthren olive T and Bezanthren grey FFB. Antibacterial activity of silver loaded dyed cotton fabrics was tested against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli. Unlike RUCO-BAC AGP synthesized silver nanoparticles deposited onto dyed cotton fabrics provided maximum bacteria reduction independently of applied dye. The stability of modified cotton fabrics was analyzed in artificial sweat at pH 5.5 and 8.0. Approximately the same amount of silver was released from differently modified cotton fabrics in artificial sweat. Larger amount of silver was released in the sweat at pH 8.0.

In order to obtain multifunctional materials with good biocompatibility and antimicrobial effect, hydroxyapatite (HAp) doped with Zn2+ was synthesized by hydrothermal method. Powders with different content of zinc ions were synthesized and compared with undoped HAp to investigation of Zn2+ ion influence on the antimicrobial activity of HAp. Analyses of undoped and Zn2+-doped powders before and after thermal treatment at 1200ºC were performed by SEM and XRD. Antimicrobial effects of powders were examined in relation to Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans in liquid medium. The results showed that the obtained powders have good antimicrobial activity, but higher antimicrobial activities of powders doped with Zn2+ were observed after annealing at 1200°C. For powders annealed at 1200°C in vitro biocompatibility tests MTT and DET with MRC-5 fibroblast cells in liquid medium were carried out. Based on MTT and DET tests it was shown that powders do not have a significant cytotoxic effect, which was confirmed by SEM analysis of MRC-5 fibroblast cells after theirs in vitro contact with powders. [Projekat Ministarstva nauke Republike Srbije, br. III 45019 and FP7-REGPOT-2009-1 NANOTECH FTM]

In this work new hybrid hydrogels were prepared by radical copolymerization of 2-hydroxyethyl methacrylate, itaconic acid, poly(vinylpyrrolidone) and silver particles. FTIR spectroscopy has confirmed binding of silver particels in hydrogels. Swelling studies performed in in vitro conditions showed dependence on PVP content and temperature. It can be seen that the antimicrobial activity of the Ag/P(HEMA/IA)PVP hybrid hydrogels depends on the PVP moiety and with the increase of PVP content the microbial contamination is more efficiently reduced. The best sensitivity was obtained for the polymers tested for antimicrobial activity against the yeast C. albicans, one of the most commonly encountered human pathogens, causing a wide variety of infections ranging from mucosal infections in generally healthy persons to life-threatening systemic infections in individuals with impaired immunity. A slightly less susceptible to antimicrobial effect of hydrogels was obtained for the Gram-positive bacteria S. aureus, where the reduction of cells was about 70 % after two hours of exposure, for the sample with the highest PVP content. The least susceptible to the antimicrobial activity of hydrogels examined was the Gram-negative bacteria E. coli, where the percent of cell reduction was below 20 %. Bearing in mind the influence of the time of exposure of microbes to the Ag/P(HEMA/IA)/PVP hybrid hydrogels, it was observed that the reduction of the number of cells depends on time, microbial culture and type of hybrid hydrogel sample. Due to their swelling and antimicrobial properties, silver/poly(2-hydroxyethyl methacrylate/itaconic acid)/poly(vinylpyrrolidone) hybrid hydrogles show potential to use in the field of biomedicine, especially for treatment of skin and burns in dermocosmetics.

The current study included the investigation of several metals and their distribution in urban soils from parks and green areas in the city of Belgrade. The soils were sampled in January and February 2008. The concentrations of Cd, Co, Cu, Pb, Mn and Zn were measured, as well as the pH values and organic matter contents. The obtained results showed that there was a significant level of contamination in some samples, especially with lead, and that it was most probably caused by anthropogenic activities, mostly from traffic. The results were compared with the National legislation and Netherlands standards. Also, the recent results were compared with the data from previous work and it was concluded that there has been a certain increase of the Pb concentration in the past three years. The level of pollution in playground soil was very high and each analyzed sample exceeded the Dutch target value for Cd, Co and Pb.

In this study, the synthesis of pentyl 2-methylpropanoate employing a commercial lipase from Candida rugosa was investigated, the emphasis being placed on analyzing the effects of various process conditions on the yield of ester. The response surface methodology (RSM) and five-level-five-factor central composite rotatable design (CCRD) were used to evaluate the effects of variables, namely the initial water content, 0.0-2.0% (w/v), the reaction temperature, 35-75°C, the enzyme concentration, 1.0-5.0 g dm-3, the acid/alcohol mole ratio, 1:2-5:2, and the reaction time, 4-48 h, on the yield (%) of ester. The production of pentyl 2-methylpropanoate was optimized and an ester yield response equation was obtained, enabling the prediction of ester yields from known values of the five main factors. It seems that the enzyme concentration, reaction time and acid/alcohol mole ratio predominantly determine the conversion process, while the amount of added water amount had no significant influence on the ester yield. Conversion of around 92 % of the substrate to ester could be realized using a concentration of lipase as low as 4.0 g dm-3 and in a relatively short time (26 h) at 35°C, when a high substrate mole ratio of 2.5 was used.

The essential oil of common juniper (Juniperus communis L., from the southern part of Serbia) and its fractions of different composition, as well as commercial antibiotics were used for testing their antimicrobial activity against bacteria, yeast and fungi. The essential oil was produced by hydro-distillation in a pilot plant (130 dm3) and then fractionated by distillation over a column, with 36 theoretical stages, under vacuum (26-66 mbar). The essential oil was also fractionated using pure CO2 or CO2 and methanol as co-solvent under supercritical conditions. The native oil showed weak antimicrobial activity, while the fractions with a high content of α-pinene, and mixture of α-pinene and sabinene showed the highest antimicrobial activity, especially against fungi. In comparison to the commercial antibiotics, the oil fractions showed more extensive spectra of antimicrobial activity, as well as wider inhibition zones. .

The antimicrobial activity of the essential oil of Melissa officinalis was investigated in this paper. The essential oil was obtained by the principle of water and steam and analyzed by GC and GC-MS using FID and MSD. The main components of the oil of Melissa officinalis were geranial (17.30%), neral (14.70%) and citronellal (10.70%). The antimicrobial properties were tested against the following bacterial species: B subtilis, B.cereus Bifidobacterium sp., Corynobacterium sp., E. coli, Klebsiella sp., L. acidophilus, L. fermentum, L. plantarum, L. rhamnosus, Listeria monocytogenes, P. vulgaris, P. aerugenosa, S. enteritidis, Shigella sp., S. aureus, and fungi Candida albicans, Alternarija sp. and Aspergillus niger. The diffusion technique was used for testing: the antimicrobial activity, and the MIC was determined by the broth dilution method. The essential oil of M. officinalis showed high antimicrobial activity.