Search results for "Bacterial activity"
showing 10 items of 178 documents
Antibacterial activity of the sponge Suberites domuncula and its primmorphs: potential basis for epibacterial chemical defense
2003
The epibacterial chemical defense of the marine sponge Suberites domuncula was explored by screening sponge extract, sponge primmorph (3-D aggregates containing proliferating cells) extract and sponge-associated as well as primmorph-associated bacteria for antibacterial activ- ity. 16S rDNA sequencing revealed that the antimicrobially active bacteria belonged to the α - and γ- subdivisions of Proteobacteria (α -Proteobacterium MBIC 3368, Idiomarina sp. and Pseudomonas sp., respectively). Moreover, a recombinant perforin-like protein was cloned from S. domuncula that dis- played strong antibacterial activity. Based on these observations, it is proposed that the sponge may be provided with a …
Chemical Composition and antimicrobial activity of the essential oils from two species of Thimus growing wild in southern Italy
2009
The volatile constituents of the aerial parts of two samples of Thymus longicaulis C. Presl, collected in Campania and in Sicily, and two samples of Thymus pulegioides L. from the same regions, were extracted by hydrodistillation and analyzed. Considering the four oils together, seventy-eight different compounds were identified: 57 for Thymus longicaulis from Sicily (91.1% of the total oil), 40 for Thymus longicaulis from Campania (91.5% of the oil), 39 for Thymus pulegioides from Sicily (92.5% of the oil) and 29 for Thymus pulegioides from Campania (90.1% of the oil). The composition of the oils is different, although the most abundant components are identical in T. pulegioides. The essent…
Cladosins L-O, new hybrid polyketides from the endophytic fungus Cladosporium sphaerospermum WBS017
2019
Abstract The endophytic fungus Cladosporium sphaerospermum WBS017 was obtained from healthy bulbs of Fritillaria unibracteata var. wabuensis. Fermentation of C. sphaerospermum on solid rice medium yielded three new hybrid polyketides, cladosins L−N (1–3), and a known derivative cladodionen (4). Further cultivation of this fungus on white bean medium afforded an additional new hybrid polyketide, cladosin O (5) along with three known analogues (6–8). The structures of the new compounds were elucidated using a combination of NMR and HRESIMS data. The absolute configurations of compounds 2 and 3 were determined by Mosher’s method and TDDFT-ECD calculations. All isolated compounds were evaluated…
Anthemis wiedemanniana essential oil prevents LPS-induced production of NO in RAW 264.7 macrophages and exerts antiproliferative and antibacterial ac…
2012
Anthemis wiedemanniana is known in folk medicine for the treatment of microbial infections, cancer and also urinary and pulmonary problems. In this study, the chemical composition of the essential oil from A. wiedemanniana was evaluated and its antibacterial activity was tested against 10 bacterial strains. The oil was also tested for its potentiality to inhibit nitric oxide production in RAW 264.7 macrophages and for its cytotoxicity against four human cancer cell lines. A. wiedemanniana oil, rich of oxygenated monoterpenes (25.4%), showed a good antibacterial activity against Gram-positive bacteria and a good activity against the two Gram-negative bacteria, Escherichia coli and Proteus vu…
Antibacterial activity of Pleurotus species
2013
Basidiomycetes express promising antitumor, immune modulating, cardiovascular and hypercholesterolemia, antiviral, antibacterial and antiparasitic effects (Wasser & Weis, 1999; Reshetnikov et al., 2001; Wasser, 2002, Didukh et al., 2003). They are also well known for their safety and efficacy as functional foods and dietary supplements (Wasser & Akavia, 2008). The antibacterial and antiviral value of different genera of Basidiomycetes has been tested by different authors (Benedict & Brady, 1972; Donnelly et al., 1986; Gao et al., 2003;). In particular the antibacterial and antiparasitic therapeutic effects were investigated in the genera Flammulina P. Karst, Fomes (Fr.) Fr., Ganoderma P. Ka…
Antibacterial and white spot lesions preventive effect of an orthodontic resin modified with silver-nanoparticles
2021
Background To evaluate the antibacterial property of a modified orthodontic resin with different concentrations of silver-nanoparticles (AgNPs), and quantify its preventive effect on the formation of white spot lesions (WSLs). Material and Methods An orthodontic resin (Transbond XT) was modified with four concentrations of AgNPs (1%, 0.5%, 0.1%, and 0.05%), the orthodontic resin without AgNPs was used as control. Polymerized resin discs (n=80) were submitted to Agar diffusion test on Petri dishes inoculated with Streptococcus mutans and Lactobacillus acidophilus. In addition, resin discs of each group (n=40) were placed in 96-well plates with bacterial suspensions to evaluate the colony-for…
Synthesis and antimicrobial activity of new bromine-rich pyrrole derivatives related to monodeoxypyoluteorin
2006
The synthesis and antimicrobial activity of new pyrrole derivatives structurally related to monodeoxypyoluteorin are described. The insertion of a keto or methylene spacer between the phenol group and the pyrroloyl moiety of brominated 2-(2'-hydroxybenzoyl)pyrroles leads to a decrease of the antibacterial activity.
Aceites esenciales: productos antimicrobianos y antioxidantes naturales en la industria agroalimentaria
2020
[ES] Los consumidores son conscientes del peligro derivado del uso de antioxidantes y antimicrobianos sintéticos en la industria agroalimentaria, demandando alternativas más seguras y ecológicas. En este estudio, se ha determinado la actividad antioxidante de aceites esenciales comerciales mediante el método DPPH y su efecto antimicrobiano frente a la bacteria Pseudomonas syringae y el hongo fitopatógeno Fusarium oxysporum a través del empleo del método estandarizado de disco. Los aceites esenciales de clavo, ajedrea, canela y orégano, así como carvacrol, mostraron la máxima actividad antioxidante, comparable a antioxidantes establecidos. El aceite esencial de gaulteria fue el más potente i…
Solvent-free microwave-assisted extraction of polyphenols from olive tree leaves: Antioxidant and antimicrobial properties
2017
International audience; Response surface methodology (RSM) and artificial neural networks (ANN) were evaluated and compared in order to decide which method was the most appropriate to predict and optimize total phenolic content (TPC) and oleuropein yields in olive tree leaf (Olea europaea) extracts, obtained after solvent-free microwave- assisted extraction (SFMAE). The SFMAE processing conditions were: microwave irradiation power 250-350 W, extraction time 2-3 min, and the amount of sample 5-10 g. Furthermore, the antioxidant and antimicrobial activities of the olive leaf extracts, obtained under optimal extraction conditions, were assessed by several in vitro assays. ANN had better predic…
Chemical composition and antibacterial effect of Smyrnium olusatrum L. Fruit Essential Oil
2020
The plants of the <em>Apiaceae</em> family are mainly used for food purposes and their multiple therapeutic properties and biological activities. This study aims to determine the chemical composition of Essential Oil (EO) of the fruits of <em>Smyrnium olusatrum</em> L. obtained by hydrodistillation in Clevenger-type apparatus. GC/MS analyzed the EO and the antibacterial activity was evaluated against clinical bacterial strains by two complementary methods (Disc diffusion and micro-atmosphere) and determination of Minimal Inhibitory Concentration (MIC). The results of chemical composition show that the EO is dominated by hydrocarbon monoterpenes (55,95%). The antibact…