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In a first step, the surfaces of polyethylene films have been modified by grafting urethane monoacrylate monomer under UV irradiation in ambient air. For native films, this grafting was successfully realized but the grafted surface was heterogeneous. To overcome this drawback and obtain a smooth and homogeneous coating, a wet oxidation method using sodium hypochlorite through two different processes was developed. The oxidation mechanism of the PE films has been established. As a consequence of the oxidation, the wettability of the grafted films was strongly increased as measured by sessile drop technique and Wilhelmy plate method. The hydrophilicity is due to carbonyl and carboxylic groups created on the treated surface. Grafting of several formulations containing different amounts of monomer, carrier and photosensitizer was successfully evidenced by analyzing the residues obtained from PE extraction in hot toluene. Indeed, FTIR, XPS, DSC and elementary analysis showed that the polyacrylate was effectively grafted on PE pre-oxidized films. Moreover, the obtained grafted surfaces corresponding to important oxidation time were homogeneous as shown by SEM and AFM. In a second step, acrylate grafting was used to induce specific properties onto the surface. This study was focused on antibacterial effect. The process starts by a dissolution of poly(4-vinylbenzyl chloride) (PVBC) in the urethane monoacrylate monomer followed by photopolymerisation of the latter. Anchoring of different PVBC based formulations was confirmed by FTIR analysis, performed onto obtained residues after extraction in hot toluene and dichloromethane. In a last step, the grafted coatings were quaternized by using triethylamine in N, N-dimethyl formamide by a nucleophilic displacement reaction. Antibacterial effect of the quaternized samples was measured by Kirby Bauer method.

In a first step, the surfaces of polyethylene films have been modified by grafting urethane monoacrylate monomer under UV irradiation in ambient air. For native films, this grafting was successfully realized but the grafted surface was heterogeneous. To overcome this drawback and obtain a smooth and homogeneous coating, a wet oxidation method using sodium hypochlorite through two different processes was developed. The oxidation mechanism of the PE films has been established. As a consequence of the oxidation, the wettability of the grafted films was strongly increased as measured by sessile drop technique and Wilhelmy plate method. The hydrophilicity is due to carbonyl and carboxylic groups created on the treated surface. Grafting of several formulations containing different amounts of monomer, carrier and photosensitizer was successfully evidenced by analyzing the residues obtained from PE extraction in hot toluene. Indeed, FTIR, XPS, DSC and elementary analysis showed that the polyacrylate was effectively grafted on PE pre-oxidized films. Moreover, the obtained grafted surfaces corresponding to important oxidation time were homogeneous as shown by SEM and AFM. In a second step, acrylate grafting was used to induce specific properties onto the surface. This study was focused on antibacterial effect. The process starts by a dissolution of poly(4-vinylbenzyl chloride) (PVBC) in the urethane monoacrylate monomer followed by photopolymerisation of the latter. Anchoring of different PVBC based formulations was confirmed by FTIR analysis, performed onto obtained residues after extraction in hot toluene and dichloromethane. In a last step, the grafted coatings were quaternized by using triethylamine in N, N-dimethyl formamide by a nucleophilic displacement reaction. Antibacterial effect of the quaternized samples was measured by Kirby Bauer method.

Objective: To evaluate the antibacterial and cytotoxic effect of Myrciaria dubia (Camu camu) (M. dubia) methanol extract, against Streptococcus mutans (ATCC 25175) (S. mutans) and Streptococcus sanguinis (ATCC 10556) (S. sanguinis). Methods: Two methanol extracts of M. dubia were prepared in vitro, from the seeds and pulp. Ten independent tests were prepared for each type of extract, using 0.12% chlorhexidine solution as positive control. Agar diffusion test was used by preparing wells with the experimental solutions cultivated in anaerobic conditions for 48 h at 37 °C. Meanwhile, the minimum inhibitory concentration and the cytotoxic effect over MDCK cell line was found. Results: A higher antibacterial effect was observed with the methanol seed extract with an inhibitory halo of (21.36 ± 6.35) mm and (19.21 ± 5.18) mm against S. mutans and S. sanguinis, respectively. The methanol extract of the pulp had an effect of (16.20 ± 2.08) mm and (19.34 ± 2.90) mm, respectively. The minimum inhibitory concentration of the pulp extract was 62.5 µg/mL for both strains, whereas for the seed antibacterial activity was observed even at low concentrations. The CC50 of the seeds extract was at a higher concentration than 800 µg/mL and 524.37 µg/mL for the pulp extract. / This study was supported by Universidad Peruana de Ciencias Aplicadas (UPC) Lima-Peru with Grant No. MANUSCRIPT ACCEPTED ACCEPTED MANUSCRIPT UPC-501-2015

Charles University in Prague Faculty of pharmacy in Hradec Králové Department of Biological and Medical science Candidate: Magdaléna And lová Supervisor: Mgr. Marcela Vejsová, Ph.D. Name of diploma thesis: Evaluation of activity of potentional antibacterial substances throught of the use microdilution broth metod Background Aim of this diploma work was research of activity of potentional antimicrobiotic substances. Research of antibacterial substances is one of the most important factor in pharmaceutic industry. The main reason is being the never stopping growth of bacterial resistence. Methods The microdilution broth metod was used to test the substances. This metod was used because of low difficulty and low cost. All the steps including the final analising was done by hand. Results The substances were divided in groups depending their chemical struction. The most effective was the salicylanilide derivates group. The other groups inhibitated growth of bacteria very little or were non-functional. In case of every bacterial stems were analised all substances which were effective. Conclusion Depending on the results the most sensitive and the most resistant bacterial stem were choosen. The most sensitive reaction on tested substances had bacterial stem Staphylococcus aureus. The Klebsiella pneumoniae...

Objective To evaluate the cytotoxic and antibacterial effect of Bixa orellana L. (B. orellana) (achiote) methanol extract against Streptococcus mutans (ATCC 25175) (S. mutans) and Streptococcus sanguinis (ATCC 10556) (S. sanguinis). Methods Two methanol extracts of B. orellana were prepared in vitro, from the seeds and leaves. The antibacterial activity of extracts against S. mutans and S. sanguinis was evaluated using the cup-plate agar diffusion method. The minimum inhibitory concentration (MIC) was determined using the microdilution method and the cytotoxic activity was determinated by using the cell line MDCK. Results A stronger antibacterial effect was observed with the leaves methanolic extract with an inhibition zone of (19.97 ± 1.31) mm against S. mutans and (19.97 ± 1.26) mm against S. sanguinis. The methanolic extract of the seeds had an activity of (15.11 ± 1.03) mm and (16.15 ± 2.15) mm against S. mutans and S. sanguinis, respectively. The MIC of the leaf and the seed extracts against S. sanguinis was 62.5 and 125 μg/mL, respectively, and the MIC of the leaf extract against S. mutans was 62.5 μg/mL, and for the seed extract it was 31.25 μg/mL. The 50% cytotoxic concentration was 366.45 and 325.05 μg/mL for the leaves and seeds extracts, respectively. Conclusions The experimental findings demonstrated the antibacterial effect of the methanolic extract of B. orellana (achiote) on S. mutans and S. sanguinis. The extract of this plant is cytotoxic at high concentrations. / Peer review

Device associated infections are a growing problem in the field of orthopaedics and dentistry. Bacteria adhering to implant surfaces and subsequent biofilm formation are challenging to treat with systemic administered antibiotics. Functionalization of implant surfaces with therapeutic coatings that are capable of inhibiting bacterial adhesion are therefore considered as a straight forward strategy to treat and prevent implant related infections. In this thesis, the use of crystalline, arc deposited TiO2 and biomimetic hydroxyapatite (HA) coatings were evaluated with respect to their potential as antibacterial surface modifications for bone-anchored implants. UV light induced photocatalysis of anatase dominated TiO2 coated surfaces was shown to provide a bactericidal effect against S. epidermidis under clinically relevant illumination times and doses. Major parts of the drug release work carried out was based on biomimetic HA (HA-B) coated fixation pins. The analysis of the coating characteristics revealed that the nanoporous structure of HA-B coatings in addition to the chemical composition and surface charge are essential parameters that influence the drug carrier performance. Loading by adsorption was demonstrated to be a feasible approach to quickly incorporate antibiotics. The controlled release of antibiotics was shown to facilitate bactericidal effects against S. aureus over application-relevant time periods, even when exposed to biomechanical forces during insertion into bone model materials. Antibiotic incorporation during coating growth was shown to promote somewhat longer drug release time periods than those obtained using adsorption loading. In summary, functionalization of implant surfaces with bioactive and biocompatible coatings is a promising concept to impact the clinical success for bone-anchored applications. The additional feature of optional, on-demand antibacterial properties of these coatings through either on-site drug release or photocatalytic antibacterial treatment is advantageous for the prevention and effective treatment of devices-associated infections. Both strategies provide an immediate response to the implant contamination by bacteria and are believed to contribute towards minimizing the origin of post-surgical infections, while at the same time improving the interfacial stability between implant and bone.

La recherche de nouvelles molécules pour combattre Pseudomonas.aeruginosa est d'une grande importance. L'utilisation des antibiotiques a spectre large a grandement accru la résistance de P.aeruginosa aux antibiotiques. Malgré cette situation, aucune nouvelle drogue active sur P.aeruginosa n'a été introduite en pratique clinique durant les 2 dernières décennies. Le monoxyde de carbone (CO) pourrait agir comme un inhibiteur efficace de la chaîne respiratoire de P.aeruginosa mais l'utilisation pratique de ce gaz comme molécule antibactérienne est gênée par sa toxicité et les difficultés de manipulation. Une avancée fondamentale récente dans le domaine de la recherche sur le CO a été la découverte des « carbon monoxide releasing molecules » (CO-RMs), qui servent de transporteur et délivre des quantités contrôlées de CO aux systèmes biologiques.Nous montrons ici que les CO-RMs possèdent des propriétés antibactériennes contre P.aeruginosa. Cet effet antibactérien des CO-RMs à lieu à des concentrations non toxiques pour les cellules eucaryotes et passe par une interaction du CO libérer par le transporteur avec la chaîne respiratoire bactérienne. Nous présentons des résultats in vivo montrant que les CO-RMs diminuent l'inoculum bactérien et augmentent la survie des souris après une bactériémie à P.aeruginosa. La comparaison de 4 CO-RMs ayant différente structures chimiques suggère que la précence d'un métal de transition joue un rôle important dans l'activité antibactérienne des CO-RMs. Une autre découverte importante présentée dans ce travail est l'inhibition de l'activité antibactérienne de certain CO-RMs par les molécules contenant des résidus thiols. Cette découverte limite la possibilité d'utiliser les CO-RMs concernés comme des agents anti-infectieux.En considérant les résultats présentés dans ce travail, l'inhibition de la chaîne respiratoire pourrait être considérée comme un nouveau mécanisme prometteur pour la recherche de nouveaux agents pharmaceutique pour combattre les infections à P.aeruginosa. / The search of new molecules to fight Pseudomonas.aeruginosa is of paramount importance. The use of broad spectrum antibiotics has greatly increased the antibiotic resistance of P.aeruginosa. In spite of this situation, no new drug against P.aeruginosa has been successfully introduced into the clinic in the past 2 decades. Carbon monoxide (CO) could act as an effective inhibitor of the respiratory chain in P. aeruginosa but the practical use of this gas as an antibacterial molecule is hampered by its toxicity and difficulty to manipulate. A recent fundamental development in the field of CO research has been the discovery of carbon monoxide-releasing molecules (CO-RMs), which serve as carriers for the delivery of controlled amounts of CO in biological systems.Here, we show that CO-RMs possesse bactericidal properties against P.aeruginosa. This antimicrobial effect of CO-RMs occurs at non toxic concentrations for eukaryotic cells and is mediated by an interaction of CO liberated by the carrier with bacterial respiratory chain. We present in vivo results showing that CO-RMs decrease bacterial inoculum and increase survival in mice following P.aeruginosa bacteraemia. A comparison of 4 CO-RMs with different chemical structures suggests that the presence of a transition metal center plays an important role in the antibacterial activity of CO-RMs. Another important finding presented in this work is the inhibition of the antibacterial activity of some CO-RMs by thiol containing molecules. This finding could deserve the possibility to use concerning CO-RMs as anti-infective agent.Considering results presented in this work, inhibition of respiratory chain could be considered as a promising new mechanism for the research in new pharmaceutical agent to fight P.aeruginosa infections.

Water supply services in urban and rural areas of Tanzania were reviewed and specific studies were carried out on water supply and on purification of turbid water sources using locally available plant materials in rural villages of Singida Rural District. The review showed that large proportions of urban and rural populations in Tanzania face acute water supply problems mainly due to poor planning, implementation and management of water supply projects, including an inability to address social, technical, operation and maintenance and financial issues. Laboratory-scale experiments studied the effectiveness of crude seed extracts (CSEs) and purified proteins of Vigna unguiculata (VUP), Parkinsonia aculeata (PAP) and Voandzeia subterranea (VS) seeds, which are used traditionally for clarification of turbid water. The VUP and PAP were purified from CSEs using simple and straightforward two-step ion exchange chromatography. The coagulant proteins are thermoresistant and have a wide pH range for coagulation activity. Coagulation of turbid waters with CSEs, VUP and PAP produced low sludge volumes and removed turbidity along with other inorganic contaminants in line with Tanzania drinking water quality standards. The PAP also showed antimicrobial effect against river water bacteria. Citrus fruit juice (CF) enhanced the coagulation of turbid water by CSEs and inhibited bacterial growth, rendering it useful for disinfection of water prior to drinking in rural areas. It was concluded that natural coagulants should not be regarded as a panacea for rural water supply problems, but rather a tool in the development of sustainable water supply services in Tanzania. / QC 20100825

Les aliments et les emballages sont interdépendants. Plusieurs réactions chimiques et physiques existent entre les aliments, l’emballage et environnement, lesquelles peuvent changer la composition, la qualité et les propriétés physiques des aliments, voire de l’emballage. L’emballage actif ou antimicrobien permet la distribution d’un aliment dans le monde entier sans perte de qualité, pendant une longue période de transport. Les antimicrobiens naturels comme la nisine, le lysozyme ou l’acide lactique contrôlent la contamination microbienne d’un aliment, améliorent son stockage, éliminent les pathogènes indésirables et retardent la prolifération microbienne. L’amélioration d’un emballage en papier, contenant de la nisine, le lysozyme, l’acide lactique, ainsi que l’étude de la synergie d’action entre antimicrobiens constituent les objectifs de cette thèse.La synergie entre nisine, lysozyme et l’acide lactique a etait déterminée avec Listeria monocyotgenes CIP 82.110 mais n’a pas observée pour Staphylococcus aureus CIP 4.83 par analyses statistiques. Le papier « activé » avec un mélange de nisine, lysozyme et acide lactique permet d’assurer une action antimicrobienne vis à vis de Listeria monocytogenes CIP 82.110 et de Staphylococcus aureus CIP 4.93. La diffusion de la nisine du papier vers un aliment simulé a était démontrée pendant 48h à la vitesse de 0.03 mg/h. En 5 jours, seulement 30% de la nisine a migré vers l’agarose. Des analyses complémentaires de diffusion vont permettre de mieux comprendre l’efficacité d’un emballage antimicrobien contenant un mélange de nisine, de lysozyme et d’acide lactique / Food and packaging are closely related. Many chemical and physical reactions exist between a food, its packages and the environment, which alter the composition, quality and physical properties of the food and/or the package. Thanks to active or antimicrobial packaging, food products can be distributed over a wide geographical area over a long period of time without unacceptable quality loss. Natural antimicrobials such as nisin, lysozyme or lactic acid improve shelf-life, eliminate undesirable pathogens and delay microbial spoilage. The present PhD thesis was focused on the improvement of paper wrapping materials by adding nisin, lactic acid and lysozyme in combination and on the determination of the synergism, which could occur between these antimicrobial agents. Synergy between nisin, lysozyme and lactic acid, which was proved against Listeria monocytogenes CIP 82.110 and was not confirmed against Staphylococcus aureus CIP 4.83 by statistical analysis. The paper, containing a mixture of nisin, lysozyme and lactic acid could ensure a antimicrobial activity against Listeria monocytogenes CIP 82.110 or Staphylococcus aureus CIP 4.93. Nisin diffusion from packaging to simulated food was demonstrated. It was proved that nisin in cellulose was only able to diffuse for 48 h at a speed of 0.03 mg/h. Only 30% of nisin was diffused from paper to gel matrix after 5 days. Extra diffusion analyses on combination of nisin, lysozyme and lactic acid should be performed to confirm the antimicrobial effectiveness of this packaging