Search results for "IBA"
showing 10 items of 1355 documents
Bioactive polyketides and alkaloids from Penicillium citrinum , a fungal endophyte isolated from Ocimum tenuiflorum
2013
Chemical investigation of the endophytic fungus Penicillium citrinum cultured on white beans or on rice led to the isolation of two new alkaloids (1 and 2), along with fourteen known polyketides (6-12, 14-20) and four known alkaloids (3-5, and 13). The structures of the isolated compounds were determined by extensive analysis of the 1D, 2D NMR, and MS data, and by comparison with the literature. Compound 13, which had been previously obtained only by chemical synthesis, was isolated as a natural product for the first time, while compound 6 was firstly reported as a fungal metabolite. A re-isolation of sclerotinin A (14) revealed it to be a diastereoisomeric mixture (14a and 14b), whose ster…
Effect of temperature on the release of carvacrol and cinnamaldehyde incorporated into polymeric systems to control growth and biofilms ofEscherichia…
2015
This study assessed the effect of temperature on the release of essential oil components incorporated by melt compounding into polymeric films. Specifically, polyethylene-co-vinylacetate (EVA) films containing carvacrol (CAR) and cinnamaldehyde (ALD), alone and in combination, were prepared and their surface and mechanical properties and antibacterial and anti-biofilm activity against Escherichia coli and Staphylococcus aureus were evaluated. The addition of ALD and CAR did not provoke variation in the surface morphology of EVA and allowed their delivery. At 37°C, films containing CAR, ALD or their combination (25+75%) were found to have the strongest bactericidal effect, whereas at lower t…
Antimicrobial Defense and Persistent Infection in Insects
2008
During 400 million years of existence, insects have rarely succumbed to the evolution of microbial resistance against their potent antimicrobial immune defenses. We found that microbial clearance after infection is extremely fast and that induced antimicrobial activity starts to increase only when most of the bacteria (99.5%) have been removed. Our experiments showed that those bacteria that survived exposure to the insect's constitutive immune response were subsequently more resistant to it. These results imply that induced antimicrobial compounds function primarily to protect the insect against the bacteria that persist within their body, rather than to clear microbial infections. These f…
Discovery of 2-aryl and 2-pyridinylbenzothiazoles endowed with antimicrobial and aryl hydrocarbon receptor agonistic activities
2020
Highlights • Sixteen functionalized benzothiazoles were evaluated as antimicrobial agents and as AhR modulators. • The benzothiazoles showed noticeable antimicrobial effects against Gram-positive and Gram-negative pathogens and against the yeast C. albicans. • Six benzothiazoles exhibited significant AhR agonist effects in a cell-based reporter gene assay. • Structure-activity relationship analysis exposed some relevant headings on the substituent's contributions to the studied biological effects. • Compound 12 displayed promising biocide activity and AhR agonism as well as an adequate ADMET profile and binding similarities with FICZ.
Staphylococcus aureus rezistence pret antimikrobajām vielām un meticilīnrezistences gēna mecA noteikšana
2022
Staphylococcus aureus ir viens no galvenajiem patogēniem, kas spēj izraisīt ādas un mīksto audu infekcijas. Rezistence pret antibiotikām ir saistīta ar plašo virulences faktoru klāstu un tā spēju izmantot horizontālu gēnu pārnesi, it īpaši meticilīnrezistences gēna mecA pārnesi. MRSA celmi vēl joprojām ir izplatīta problēma veselības aprūpē. Darba mērķis: Noteikt Staphylococcus aureus klīnisko izolātu jutību pret antimikrobiālajiem līdzekļiem un mecA gēna klātesamību, izmantojot BBL™ disku difūzijas testu, E-testu un FilmArray ® Multiplex PCR metodi. Rezultāti: Visaugstākā antibakteriālā jutība bija pret rifampicīnu (98,91%), kā arī augsta jutība bija pret cefoksitīnu (96,74%) un trimetopri…
Meticilīnrezistences gēna mecA un toksīna PVL sintēzi noteicošā gēna luk molekulāri bioloģiskā noteikšana Staphylococcus aureus izolātos
2021
Staphylococcus aureus, it īpaši tā meticilīnrezistentie celmi ir vieni no izturīgākajiem mikroorganismiem visā pasaulē, kas pateicoties tiem piemītošajai ģenētiskajai daudzveidībai spēj mainīt sev piederošo virulences faktoru ekspresiju. Tā rezultātā kļūstot par strukturāli un ķīmiski daudzveidīgiem mikroorganismiem, kam ir būtiska loma ar veselības aprūpi saistīto infekciju izplatībā. Mūsdienās, neskatoties uz pēdējos gados vērojamo MRSA celmu izplatības samazināšanos lielākajā daļā ES lielvalstu, arvien biežāk tiek ziņots par pieaugošu Panton-Valentine leikocidīna pozitīvu S. aureus celmu izplatību. Pateicoties, kam tiek sekmēta gan antibakteriālās rezistences attīstība, gan organisma imū…
Elpceļu infekciju gadījumos izdalīto Staphylococcus aureus jutība pret antibakteriālajiem līdzekļiem
2017
S.aureus ir gram + pozitīva baktērija, kas ir lokalizējusies degunā elpošanas traktā un uz ādas un ne vienmer ir patogēns mikroorganisms. Spēj ģēnētiski izmainīt savu šūnapvalka olbaltumvielas, padarot tos rezistentus pret antibiotikām. Meticilīn-rezistentais S. aureus (MRSA) satur mecA gēnu, kas nodrošina mikroorganismam rezistenci ne tikai pret meticilīnu un b - laktāma grupas antibiotikām, bet arī pret cefalosporīniem un citām grupām. Rezistences attīstība patogēniem ir saistīta ar plašu un bieži nepamatotu antibiotiku lietošanu terapijā. Darba mērķis: Noteikt S. aureus jutību pret antibakteriālajiem līdzekļiem, celmiem, kas izdalīti no elpceļu materiāla. Darba uzdevumi: Veikt laboratori…
In vitro antibacterial and biofilm inhibitory activity of the sawdust essential oil of Tetraclinis articulata (vahl) against catheter-associated Stap…
2021
Abstract The aim of the present study was to determine the chemical composition, antibacterial and antibiofilm activities of the essential oil of sawdust from root burl wood of T. articulata. Nine strains including 8 clinical isolates from catheters-related infections and one ATCC 25923 were tested. Twenty-seven different compounds were identified by GC–MS in the essential oil of T. articulata extracted by hydrodistillation. Carvacrol and cedrol were the principal compounds representing 34.37 ± 0.07 and 11.07 ± 0.09 respectively. The EO had a strong antibacterial activity against all strains including one Multidrug-Resistant (MDR) and two Methicillin-Resistant S. aureus strains. Inhibition …
Antibacterial Activity of Desert Truffles from Saudi Arabia Against Staphylococcus aureus and Pseudomonas aeruginosa
2017
Abstract Medicinal mushrooms represent an unlimited source of polysaccharides with nutritional, antitumoral, antibacterial, and immune-stimulating properties. Traditional studies of epigeous higher Basidiomycetes have recently been joined by studies of hypogeous fungi and, in particular, of so-called desert truffles. With the aim to obtain novel agents against bacteria of clinical importance, we focused on the edible desert truffle mushrooms Tirmania pinoyi, Terfezia claveryi, and Picoa juniperi as sources of new antimicrobial agents. In particular, we investigated the in vitro antibacterial activity of acid-soluble protein extracts (aqueous extracts) of these 3 species against the Gram-pos…
A Silicone Ventricular Catheter Coated with a Combination of Rifampin and Trimethoprim for the Prevention of Catheter-related Infections
1998
So-called antiinfective catheters which are generated by incorporation of antimicrobial substances into polymers appear to be effectful devices in the prevention of catheter related infections. Such devices mainly act by prevention of bacterial colonization of the catheter surface rather than by inhibition of adherence. In a preceding study, we developed a rifampin-containing silicone catheter for the prevention of ventricular shunt infection. In the present study, this work was continued with a combination of antimicrobials incorporated in silicone ventricular catheters to reduce the risk of rifampin resistance and to expand the antimicrobial spectrum. We found that the drug release kineti…