Antibacterial activity of Thymoquinone, an active principle of Nigella sativa and its potency to prevent bacterial biofilm formation

<p>Abstract</p> <p>Background</p> <p>Thymoquinone is an active principle of <it>Nigella sativa </it>seed known as "Habbah Al-Sauda" in Arabic countries and "Sinouj" in Tunisia. Bacterial biofilms tend to exhibit significant tolerance to antimicrobials drugs during infections.</p> <p>Methods</p> <p>The antibacterial activity of Thymoquinone (TQ) and its biofilm inhibition potencies were investigated on 11 human pathogenic bacteria. The growth and development of the biofilm were assessed using the crystal violet (CV) and the 2, 3-bis [2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT) reduction assay.</p> <p>Results</p> <p>TQ exhibited a significant bactericidal activity against the majority of the tested bacteria (MICs values ranged from 8 to 32 μg/ml) especially Gram positive cocci (<it>Staphylococcus aureus </it>ATCC 25923 and <it>Staphylococcus epidermidis </it>CIP 106510). Crystal violet assay demonstrated that the minimum biofilm inhibition concentration (BIC50) was reached with 22 and 60 μg/ml for <it>Staphylococcus aureus </it>ATCC 25923 and <it>Staphylococcus epidermidis </it>CIP 106510 respectively. In addition our data revealed that cells oxidative activity was influenced by TQ supplementation. In the same way, TQ prevented cell adhesion to glass slides surface.</p> <p>Conclusion</p> <p>The ability of TQ to prevent biofilm formation warrants further investigation to explore its use as bioactive substances with antibiofilm potential.</p

Bumble bee parasite strains vary in resistance to phytochemicals

Nectar and pollen contain diverse phytochemicals that can reduce disease in pollinators. However, prior studies showed variable effects of nectar chemicals on infection, which could reflect variable phytochemical resistance among parasite strains. Inter-strain variation in resistance could influence evolutionary interactions between plants, pollinators, and pollinator disease, but testing direct effects of phytochemicals on parasites requires elimination of variation between bees. Using cell cultures of the bumble bee parasite Crithidia bombi, we determined (1) growth-inhibiting effects of nine floral phytochemicals and (2) variation in phytochemical resistance among four parasite strains. C. bombi growth was unaffected by naturally occurring concentrations of the known antitrypanosomal phenolics gallic acid, caffeic acid, and chlorogenic acid. However, C. bombi growth was inhibited by anabasine, eugenol, and thymol. Strains varied >3-fold in phytochemical resistance, suggesting that selection for phytochemical resistance could drive parasite evolution. Inhibitory concentrations of thymol (4.53-22.2 ppm) were similar to concentrations in Thymus vulgaris nectar (mean 5.2 ppm). Exposure of C. bombi to naturally occurring levels of phytochemicals—either within bees or during parasite transmission via flowers—could influence infection in nature. Flowers that produce antiparasitic phytochemical, including thymol, could potentially reduce infection in Bombus populations, thereby counteracting a possible contributor to pollinator decline

Marketing communication of tourist destination

Tato bakalářská práce se soustředí na zhodnocení marketingové komunikace pro předem vybranou destinaci - Karlovarský kraj. První kapitola obsahuje teoretický přehled zkoumaného problému. Nejprve je představen pojem destinace a popsán destinační marketing včetně strategického a taktického marketingu destinace. Dále je pozornost věnována vymezení marketingovému mixu destinace cestovního ruchu, která se váže na cestovní ruch společně s popsáním jednotlivých prvků marketingové komunikace destinace. V neposlední řadě jsou formulovány výzkumné předpoklady, které budou v průběhu práce potvrzeny či vyvráceny. Ve druhé kapitole je popsána metodika výzkumné části práce, přičemž ve třetí kapitole jsou shrnuty výsledky z primárních a sekundárních zdrojů. Ve čtvrté kapitole poté dochází k vytvoření návrhu určenému pro marketingovou komunikaci zvolené destinace.ObhájenoThis bachelor thesis focuses on the evaluation of marketing communication for a pre-selected destination - the Karlovy Vary Region. The first chapter contains a theoretical overview of the problem under study. First, the concept of destination is introduced and destination marketing is described, including strategic and tactical destination marketing. Next, attention is paid to the definition of the destination marketing mix related to tourism together with a description of the individual elements of destination marketing communication. Finally, research assumptions are formulated which will be confirmed or refuted in the course of the thesis. Chapter two describes the methodology of the research part of the thesis, while chapter three summarises the results from primary and secondary sources. Chapter four then leads to the development of a proposal intended for the marketing communication of the chosen destination

Popis historicko-archeologicko-statistický okresu Opočenského

monografi

Marketing communication of tourist destination

Tato bakalářská práce se soustředí na zhodnocení marketingové komunikace pro předem vybranou destinaci - Karlovarský kraj. První kapitola obsahuje teoretický přehled zkoumaného problému. Nejprve je představen pojem destinace a popsán destinační marketing včetně strategického a taktického marketingu destinace. Dále je pozornost věnována vymezení marketingovému mixu destinace cestovního ruchu, která se váže na cestovní ruch společně s popsáním jednotlivých prvků marketingové komunikace destinace. V neposlední řadě jsou formulovány výzkumné předpoklady, které budou v průběhu práce potvrzeny či vyvráceny. Ve druhé kapitole je popsána metodika výzkumné části práce, přičemž ve třetí kapitole jsou shrnuty výsledky z primárních a sekundárních zdrojů. Ve čtvrté kapitole poté dochází k vytvoření návrhu určenému pro marketingovou komunikaci zvolené destinace.ObhájenoThis bachelor thesis focuses on the evaluation of marketing communication for a pre-selected destination - the Karlovy Vary Region. The first chapter contains a theoretical overview of the problem under study. First, the concept of destination is introduced and destination marketing is described, including strategic and tactical destination marketing. Next, attention is paid to the definition of the destination marketing mix related to tourism together with a description of the individual elements of destination marketing communication. Finally, research assumptions are formulated which will be confirmed or refuted in the course of the thesis. Chapter two describes the methodology of the research part of the thesis, while chapter three summarises the results from primary and secondary sources. Chapter four then leads to the development of a proposal intended for the marketing communication of the chosen destination

Selective Growth Inhibitory Effect of Biochanin A Against Intestinal Tract Colonizing Bacteria

molecule

In vitro growth-inhibitory effect of plant-derived extracts and compounds against Paenibacillus larvae and their acute oral toxicity to adult honey bees

In total, 26 natural compounds of various chemical classes (flavonoids, alkaloids, terpenoids) and 19 crude extracts from selected plants were tested in vitro for antibacterial activity against three strains of P. larvae, the causal agent of American Foulbrood Disease of honey bees (AFB) by the broth microdilution method. Among the individual substances, sanguinarine (MIC 4 μg/ml), followed by thymoquinone, capsaicin, trans-2-hexenal and nordihydroguaiaretic acid (MIC 4–32 μg/ml) possessed the strongest antibacterial effect. In case of extracts, common hop (Humulus lupulus L.) and myrtle (Myrtus communis L.) methanolic-dichloromethane extracts exhibited the highest growth-inhibitory effect with MICs ranging from 2 to 8 μg/ml. Acute oral toxicity of the most active natural products was determined on adult honey bees, showing them as non-toxic at concentrations as high as 100 μg peer bee. Our study leads to identification of highly potent natural products effective against AFB in vitro with very low MICs compared to those reported in literature, low toxicity to adult honey bees and commercial availability suggesting them as perspective, low cost and consumer-acceptable agents for control of AFB

In vitro inhibitory activity of essential oil vapors against Ascosphaera apis

This work evaluates the in vitro inhibitory activity of 70 essential oils (EOs) in the vapor phase for the control of Chalkbrood disease caused by Ascosphaera apis Maassen ex Claussen (Olive et Spiltoir). Two wild strains isolated from infected honey bee colonies together with one standard collection strain were tested by the microatmosphere method. From 70 EOs, 39 exhibited an antifungal effect against A. apis standard and wild strains. The greatest antifungal action was observed for EO vapors from Armoracia ruslicana, followed by Thymus vulgaris, Cymbopogon flexosus, Origanum vulgare and Allium sativum. An investigation of chemical composition by GC-MS revealed, that the most active EOs contained allyl isothiocyanate, citral, carvacrol and diallyl sulfides as the main constituents. The chemical composition plays a key role, as activities of different EOs from the same botanical species were different according to their composition

In vitro inhibitory activity of essential oil vapors against Ascosphaera apis

This work evaluates the in vitro inhibitory activity of 70 essential oils (EOs) in the vapor phase for the control of Chalkbrood disease caused by Ascosphaera apis Maassen ex Claussen (Olive et Spiltoir). Two wild strains isolated from infected honey bee colonies together with one standard collection strain were tested by the microatmosphere method. From 70 EOs, 39 exhibited an antifungal effect against A. apis standard and wild strains. The greatest antifungal action was observed for EO vapors from Armoracia ruslicana, followed by Thymus vulgaris, Cymbopogon flexosus, Origanum vulgare and Allium sativum. An investigation of chemical composition by GC-MS revealed, that the most active EOs contained allyl isothiocyanate, citral, carvacrol and diallyl sulfides as the main constituents. The chemical composition plays a key role, as activities of different EOs from the same botanical species were different according to their composition