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PL
Withania somnifera (L.) Dun. (Solanaceae) jest rośliną leczniczą, w stanie naturalnym występującą w regionie subtropikalnym. Głównymi związkami aktywnymi biologicznie, izolowanymi z tego gatunku, są witaferyna A, witanolid D oraz sitoindozydy. Posiadają one właściwości przeciwbakteryjne, przeciwgrzybowe, przeciwnowotworowe, cytotoksyczne, uczulające na promieniowanie, przeciwutleniające, przeciwstresowe, adaptogenne i immunosupresyjne. W pracy przedstawiono efekt działania różnych szczepów Agrobacterium rhizogenes na tworzenie się korzeni transformowanych Withania somnifera. Do wstępnej identyfikacji witaferyny A i witanolidu D, w materiale biologicznym wyhodowanym in vitro, wykorzystano metodę TLC. Te same wartości Rf wskazują, że ekstrakty z korzeni zawierają witanolid D a ekstrakty z zielonych pędów witanolid D i witaferynę A. Metanolowy wyciąg z korzeni transformowanych wykazywał aktywność przeciwbakteryjną w stosunku do Pseudomonas aeruginosa, Escherichia coli, Micrococcus flavus. Podobny ekstrakt z pędów zielonych działał na bakterie Staphylococcus aureus i Micrococcus flavus; nie wykazywał aktywności w stosunku do Enterobacteriaceae.
EN
Withania somnifera (L.) Dun. (Solanacae) is the medicinal plant widely distributed in dry subtropical region. Withaferin-A, withanolide-D and sitoindosides are the main biobgical active compounds (withanolides) isolated from Withania somnifera. They show antibacterial, antifungal, antitumor, cytotoxic, radiosensitizing, antioxidant, antistress, adaptogenic and immunosupressive properties. Here we report the effect of different strains of Agrobacterium rhizogenes (LBA 9402, ATCC 15834, TR 104) on Withania somnifera transformed roots. We search for withaferin-A and withanolide D in normal roots of intact plants growing in India, as well as in untransformed and transformed hairy roots obtained in vitro. TLC method was used for preliminary withanolides identification. The same value of Rf indicated that extracts of roots may containe withanolide D, extracts from green shoots - withanolide D and withaferin A. Methanolic extracts from transformed roots showed antibacterial activity on Proteus vulgaris NCTC 4635, Escherichia coli NCTC 8196 and Micrococcus flavus NCIB 8166. The extracts from green shoots showed antibacterial activity on Staphylococcus aureus NCTC 4163 and Micrococcus flavus NCIB 8166, but not on Enterobacteriaceae.
EN
Staphylococcus epidermidis, a coagulase-negative Staphylococcus, is the most important pathogen responsible for chronic nosocomial infections. These bacteria produce extracellular slime and form biofilms on various biotic and abiotic surfaces. Bacterial biofilms are very resistant to standard antimicrobial therapy and difficult to eradicate, so it is important to search for new more effective anti-biofilm agents, for example in the group of natural substances. The aim of the study was to examine the activity of two ionophores-salinomycin and monensin against clinical S. epidermidis strains, using MIC/MBC method and biofilm formation inhibition assay. Bacterial strains were tested also for slime production using Congo Red Agar. Both tested ionophore antibiotics showed the highest activity against planktonic bacteria of clinical as well as standard S. epidermidis strains and effectively inhibited the formation of bacterial biofilm.
PL
Celem przedstawionych badań była ocena dwóch metod wykrywania biofil- mu bakteryjnego tworzonego przez kliniczne szczepy Staphylococcus aureus wyizolowane z plwociny pacjentów z mukowiscydozą oraz ocena tworzenia biofilmu na powierzchni dołków płytek polistyrenowych w zależności od użytego podłoża hodowlanego (LB, BHI, TSBglu). Zdolność i intensywność tworzenia biofilmu analizowano metodą barwienia z użyciem fioletu krystalicznego (CV) oraz metodą oceny redukcji chlorku 2,3,5-trójfenylotetrazoliowego (TTC). Stwierdzono, że obydwie metody barwienia okazały się przydatne do oceny powstającego biofilmu gronkowcowego. Za najbardziej optymalne podłoże do hodowli biofilmu gronkowcowego uznano podłoże LB.
EN
The purpose of this study was to evaluate two screening methods for detection of biofilm formation by eighty clinical Staphylococcus aureus isolates from patients with cystic fibrosis, and evaluation of biofilm production on the polystyrene 96-well tissue culture plates, depending on media applied. All clinical strains were incubated in three different media: Luria-Bertani broth (LB), tryptic soy broth supplemented with 2% glucose (TSBglu) and brain heart infusion (BHI). Biofilm production was screened by staining with crystal violet (CV) or with 2,3,5-triphenyltetrazolium chloride (TTC). Both CV and TTC assays showed, that all analyzed isolates created biofilm, in all tested media, however with different intensity. In conclusion, the CV method was found to be more sensitive than the TTC method, when we need information about whole mass of biofilm. The most optimal medium for the biofilm culture was LB medium.
EN
Quaternary ammonium compounds are broad-spectrum bacteriocides widely used as antiseptics, disinfection and preservation agents. The aim of this study was to examine the activity of two quaternary ammonium salts, cetylpyridinum bromide and a newly synthesized quaternary bis ammonium salt, against S. epidermidis biofilm. The average values of killing efficiency for cetylpyridinum bromide ranged from 26.6% to 64.1% for all tested concentrations (0.125 to 8.0 μg×mL⁻¹) and for quaternary bis ammonium salt the percentage of killing efficiency ranged from 59.7% to 88.4% for tested concentrations (from 2.0 to 128.0 μg×mL⁻¹). Both tested compounds significantly affect staphylococcal biofilms, but any of used concentrations caused a total eradication of bacterial biofilm.
EN
Five of thiourea derivatives were prepared using as a starting compound 3-(trifluoromethyl)aniline, 4-chloro-3-nitroaniline, 1,3-thiazol-2-amine, 2H-1,2,3-triazol-4-amine and commercial isothiocyanates. All compounds were evaluated in vitro for antimicrobial activity. Derivatives 2 and 3 showed the highest inhibition against Gram-positive cocci (standard and hospital strains). The observed MIC values were in the range of 0.5–8 μg/ml. The products effectively inhibited the formation of biofilms of methicillin-resistant and standard strains of Staphylococcus epidermidis. Inhibitory activity of thioureas 2 and 3 against Staphylococcus aureus topoisomerase IV was studied. The examined compounds were nongenotoxic.
PL
Badano poziom wrażliwości 90 szczepów Staphylococcus aureus izolowanych od pacjentów hospitalizowanych oraz pochodzących ze środowiska pozaszpitalnego na wybrane czwartorzędowe sole amoniowe i chlorheksydynę.
EN
The level of susceptibility of 90 different Staphylococcus aureus strains to chosen quaternary ammonium compounds: cetyltrimethyl ammonium bromide, benzalkonium chloride and benzethonium chloride as well as to chlorhexidine digluconate were examined. The examined strains consist of three groups: hospital originated MRSA, hospital originated MSSA and non-hospital MSSA. The significant differences between these groups were observed in they susccptibility to the investigated disinfectants. The obtained MIC values showed that the most resistant were hospital MRSA strains, where 55% was estimated as resistant to cetyltrimethyl amnonium bromide, 72% were resistant to benzalkonium chloride and benzethonium chloride and 7% were resistant to chlorhexidine digluconate. Among hospital originated MSSA 3% of strains were resistant to cetyltrimethyl ammonium bromide and 6% were resistant to benzalkonium chloride and benzethonium chloride. 14% non-hospital .S. aureus strains were resistant to benzalkonium chloride and benzethonium chloride. None were resistant to chlorhexidine digluconate or cetylthrimethyl ammonium bromide.
PL
U 31 szczepów Staphylococcus aureus, badano obecność genów smr i qacA przy zastosowaniu metody PCR. Badaniami objęto 22 szczepy MRSA (w tym 20 opornych na czwartorzędowe sole amoniowe) oraz 9 szczepów MSSA.
EN
The 31 strains of Staphylococcus aureus were examined for the presence of smr and qacA determinants. The smr gene was found in 15 strains. Fourteen of them were MRSA resistant to quaternary ammonium compounds, ethidium bromide, and acriflavine. One was MSSA strain resistant to ethidium bromide and acriflavine. The qacA gene was found in two MRSA strains resistant to quaternary ammonium compounds, ethidium bromide, chlorhexidine andacriflavine. One of these two strains possessed both smr and qacA genes.
EN
Antibacterial and antifungal activity of 2,4-dihydro-[1,2,4]triazol-3-one derivatives were examined by the disc-diffusion method (growth inhibition zone diameter in agar medium). The MIC's for the most active agents were determined. Of all the tested compounds, aminomethy1 derivatives of 2,4-dihydro-[1,2,4]triazol-3-one exhibit activity against the majority of microorganisms studied.
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