Search results for "bacterial activity"
showing 10 items of 178 documents
Bioactive compounds from brown algae inhabiting the north-western Mediterranean Sea
2021
Marine algae produce a great amount of secondary metabolites (e.g. terpenoids, fatty acids, steroids, polysaccharides and polyphenols) to face environmental stressors they are exposed to, but also to defend themselves from biological pressures such as competitors, pathogens, grazers and epiphytes. Over the last decade, secondary metabolites isolated from brown algae and phenolic compounds, in particular, are receiving increasing attention due to their putative ecological roles, and several biological properties. Brown fucoid algae of the genus Cystoseira sensu latu (Sargassaceae) and Dictyotaceae produce a wide variety of secondary metabolites which have been investigated mainly for their d…
Discovery of plants and fungi with antibacterial activity against Propionibacterium acnes
2016
Acne vulgaris is a common skin disorder that affects >85% of teenagers. Propionibacterium acnes is implicated in its pathogenesis, and like many other bacteria, is subject to emerging trends in antibiotic resistance. Novel therapies are in high demand. The aim of this study was to identify new leads for future pre-clinical development from herbal skin remedies used in Italy. We screened a unique natural product library composed of extracts from medicinal and randomly collected plants and fungi from the Mediterranean for growth-inhibitory and anti-biofilm activity in P. acnes. Evaluation of 157 extracts from 10 fungi and 58 plants led to the identification of crude extracts from seven specie…
Essential oil composition and antibacterial activity of Anthemis mixta L. and Anthemis tomentosa L. (Asteraceae)
2012
In the present study the chemical composition of the essential oils from aerial parts and roots of Anthemis mixta L. and A. tomentosa L. was evaluated by GC and GC-MS, and their antibacterial activity tested against ten bacterial species. Hexadecanoic acid (15.2%) was recognized as the main constituent of A. mixta, together with τ-cadinol (6.7%), while in both aerial parts and roots of A. tomentosa nonacosane (21.9% and 20.7%), heptacosane (8.1% and 6.0%), hexadecanoic acid (8.1% and 27.1%) and hexahydrofarnesylacetone (6.8% and 5.5%) prevailed. The oils from aerial parts of both species showed a good activity against Gram-positive bacteria. These results suggest that the plants could be po…
Enhancing Biocompatibility and Antibacterial Activity of Ti6Al4V by Entrapping Ag and Hydroxyapatite Inside Alginate Filled Pores of TiO 2 Layer Grow…
2022
A three-step electrochemical process is developed to grow a coating on Ti6Al4V alloy for biomedical applications aimed to enhance its bioactivity. The coating is composed by a porous titanium oxide filled with Ag, alginic acid, and hydroxyapatite to provide antibacterial properties and, at the same time, osteointegration capability. Anodized and treated with the electrochemical process samples are characterized by Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDX), X-Ray Diffraction, and Raman Spectroscopy to have information about morphology and composition soon after the fabrication and after immersion in Hanks' solution. Bioactivity of the samples is also prov…
In vitro antibacterial activity of endodontic sealers
2004
Summary Objectives To evaluate the antibacterial activity of four endodontic sealers: one epoxy resin sealer (AH Plus), two zinc oxide eugenol (ZOE)-based sealers (Endomethasone, Pulp Canal Sealer), and one sealer containing both ZOE and orthophenilphenol (Vcanalare). Methods A direct contact test (DCT) was performed. A 10 μl suspension of Enterococcus faecalis was placed on the test material 20 min, 24 h and 7 days after mixing. Bacteria were allowed to directly contact the sealers for 1 h at 37 °C. Bacterial growth was then spectrophotometrically measured every 30 min for 7 h, and again after 24 h as well. Results All freshly mixed sealers showed complete inhibition of bacterial growth. S…
Chemical Composition and Antibacterial Potential of Artemisia arborescens L. Essential Oil
2011
This study was undertaken to characterize the essential oil (EO) of Artemisia arborescens growing wild in Sicily. EO, extracted by steam distillation, was examined for its chemical composition and for its capability to inhibit some food-borne pathogen bacteria. A total of 43 compounds (13 monoterpene hydrocarbons, 14 oxygenated monoterpenes, 10 sesquiterpene hydrocarbons, three oxygenated sesquiterpenes and less amount of other three compounds), which account 93.73% of the total oil, were identified by gas chromatography and gas chromatography-mass spectrometry. Oxygenated monoterpenes (57.32%) constituted the main fraction, with β-thujone as the main compound (45.04%), followed by the sesq…
In vitro evaluation of the antibacterial activity of cured dentin/enamel adhesive incorporating the antimicrobial agent MDPB
2010
The aim of this study was to investigate in vitro the antibacterial effect of a dentin/enamel adhesive containing MDPB (Clearfil Protect Bond) after curing and to compare it with an adhesive not containing MDPB (Clearfil SE Bond). The antibacterial effect of the cured adhesives was tested on Enterococcus faecalis by the evaluation of growth inhibition in a 48-h microplate direct contact test (DCT). The presence of antibacterial activity due to soluble components was also investigated by an agar diffusion test (ADT) performed with the adhesives cured on the surface of dentin disks. In the DCT, both the tested materials showed complete inhibition of bacterial growth until the 7-h reading, reg…
Bacterial growth and biological properties of Cymbopogon schoenanthus and Ziziphus lotus are modulated by extraction conditions
2020
Abstract The present study aims to evaluate the antibacterial activity and biological properties of two traditional Saharian plants (Cymbopogon schoenanthus and Ziziphus lotus). The plant extracts were obtained by using a different combination of extraction methods (conventional vs. ultrasound-assisted) and solvents (water vs. ethanol:water (50:50, v/v)). The antioxidant profile, anti-inflammatory activity and impact on bacterial growth (foodborne and probiotic bacteria) of the obtained extracts were assessed. The plant species showed the hierarchically more important role in determining the biological properties of the extracts, followed by extraction solvent and extraction conditions. Con…
Origanum vulgare subsp. hirtum Essential Oil Prevented Biofilm formation and showed antibacterial activity against planktonic and sessile bacterial c…
2013
Essential oils from six different populations of Origanum vulgare subsp. hirtum were compared for their antibiofilm properties. The six essential oils (A to F) were characterized by a combination of gas chromatography with flame ionization detector and gas chromatography with mass spectrometer detector analyses. All oils showed weak activity against the planktonic form of a group of Staphylococcus aureus strains and against a Pseudomonas aeruginosa ATCC 15442 reference strain. The ability to inhibit biofilm formation was investigated at sub-MIC levels of 200, 100, and 50 m g/ml by staining sessile cells with safranin. Sample E showed the highest average effectiveness against all tested stra…
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…