Search results for "microbial"
showing 10 items of 2041 documents
Induction of new metabolites from sponge-associated fungus Aspergillus carneus by OSMAC approach.
2018
Abstract A comparative study on the metabolic profile of the sponge-associated fungus Aspergillus carneus using the OSMAC approach was conducted. The fungal strain was fermented on three different media including solid rice medium with or without sea salt and modified Czapek medium. Three new natural products, isopropylchaetominine (1), isoterrelumamide A (2) and 5′-epi-averufanin (3), together with fourteen known compounds (4–17) were isolated. The structures of the new compounds were established by 1D and 2D NMR spectroscopic analysis as well as by HRESIMS. Compound 2 was only found when the fungus was cultivated on modified Czapek medium, whereas compounds 4, 7, 11, 12, and 14 were only …
Antimicrobial and Antioxidant Activities of Coumarins from the Roots of Ferulago campestris (Apiaceae)
2009
We report the isolation of several coumarins and the stereochemical assessment of some pyranocoumarins, as well as the antibacterial and antioxidant activities of the three most abundant ones (grandivittin, agasyllin and aegelinol benzoate) isolated from the roots of Ferulago campestris collected in Sicily and of the hydrolysis product (aegelinol). Aegelinol and agasyllin showed antibacterial activity against nine ATCC and the same clinically isolated Gram-positive and Gram-negative bacterial strains. At a concentration between 16 and 125 μg/mL both coumarins showed a significant antibacterial effect against both Gram-negative and Gram-positive bacteria. In particular the ATCC strains Staph…
The influence of Opuntia ficus-indica mucilage edible coating on the quality of ‘Hayward’ kiwifruit slices
2016
Abstract The aim of this work was to study the effect of mucilage edible coating extracted from Opuntia ficus-indica (OFI) on the quality and shelf life maintenance of packaged kiwifruit slices. OFI mucilage alone or added with TWEEN ® 20 were applied on kiwifruit fresh cut surfaces. After treatments, kiwifruit samples were stored under passive atmosphere at 5 ± 1 °C for 3, 5, 7 and 12 days. At each storage period, visual quality and flavor score, pectin content, ascorbic acid and the microbiological characteristics were measured together with CO 2 and O 2 content in the packages. Kiwifruit slices coated only with mucilage or with mucilage plus Tween 20, showed a significant higher firmness…
Isolation of Gram-positive n-alkane degraders from a hydrocarbon-contaminated Mediterranean shoreline.
2007
Aims: To investigate the petroleum hydrocarbon (HC)-degrading potential of indigenous micro-organisms in a sandy Mediterranean coast, accidentally contaminated with petroleum-derived HCs. Methods and Results: Using culturable methods, a population of Gram-positive n-alkane degraders was detected in the contaminated soil. Five isolates, identified as one Nocardia, two Rhodococcus and two Gordonia strains, were able to degrade medium- and long-chain n-alkanes up to C36 as assessed by growth assays and gas chromatography-mass spectrometry analysis. Diverging alkane hydroxylase-encoding genes (alkB) were detected by PCR, using degenerated primers, in all the strains; multiple sequences were obt…
Importance and efficiency of in-depth antimicrobial activity for the control of listeria development with nisin-incorporated sodium caseinate films
2010
Abstract The effect of antimicrobial sodium caseinate-based films was investigated on inhibition of Listeria innocua in cheese. Nisin was incorporated into sorbitol-plasticized sodium caseinate films at 1000 IU/cm2 and the films were prepared by casting methods. Mini red Babybel® cheese was chosen as a semi-soft cheese model. The antimicrobial activity was studied based on the contact between antimicrobial films and surface-contaminated as well as in-depth contaminated cheese samples during a 7-day storage at 4 °C. The active films produced resulted in a reduction of 1.1 log CFU/g reduction in L. innocua counts in surface-inoculated cheese samples after 1 week of storage as compared to cont…
Antibacterial effect of a new haemostatic agent on oral microorganisms
2011
Objective: The purpose of this study was to determine the antibacterial effect of a newly developed haemostatic agent Ankaferd Blood Stopper® (ABS) and Ferric Sulphate (FS) on various oral microorganisms. Study design: Bacterial strains were freshly incubated in their specific broth media. For each of the strains, 3 wells per each agent, with a 5 mm diameter were made under aseptic conditions in the specific agar media. Then they were filled with a test agents or 0.2% chlorhexidine digluconate (CHX) (control group). After 24h and 48h incubation periods, inhibition zones were measured. Results: ABS showed antibacterial effect on all test microorganisms except Lactobacillus acidophilus and La…
Sensitivity to acetic acid, ability to colonize abiotic surfaces and virulence potential of Listeria monocytogenes EGD-e after incubation on parsley …
2010
International audience; Abstract Aim: To investigate how the survival of Listeria monocytogenes on parsley leaves may affect its ability to sustain process-related harsh conditions and its virulence. Methods and Results: Parsley seedlings were spot inoculated with stationary phase cells of L. monocytogenes EGD-e and incubated for 15 days. Each day, bacterial cells were harvested and enumerated, and their ability to survive acetic acid challenge (90 min, pH 4.0), to colonize abiotic surfaces and to grow as biofilms was assessed. After a 3-log decrease over the first 48 h, the population stabilized to about 10(6) CFU g(-1) until the sixth day. After the sixth day, L. monocytogenes was no long…
Ogniwa paliwowe i mikrobiologiczne ogniwa paliwowe - zastosowanie druku 3D
2018
Technologie ogniw paliwowych i mikrobiologicznych ogniw paliwowych mogą stać się w przyszłości jednymi z dominujących technologii wytwarzania energii elektrycznej. Konieczne są więc badania związane z tymi technologiami. Technologią, która może usprawnić prowadzenie badań w tym zakresie jest technologia druku 3D. Pozwala ona na wykonywanie dowolnych kształtów w jednym egzemplarzu. Ponadto koszt projektu i wydruku jest stosunkowo niski. Dzięki tej technologii można znacznie przyspieszyć prowadzenie badań z zakresu ogniw paliwowych i mikrobiologicznych ogniw paliwowych. Praca przedstawia wykorzystanie druku 3D w badaniach nad ogniwami paliwowymi i mikrobiologicznymi ogniwami paliwowymi prowad…
Validation and application of a PCR primer set to quantify fungal communities in the soil environment by real-time quantitative PCR
2011
Fungi constitute an important group in soil biological diversity and functioning. However, characterization and knowledge of fungal communities is hampered because few primer sets are available to quantify fungal abundance by real-time quantitative PCR (real-time Q-PCR). The aim in this study was to quantify fungal abundance in soils by incorporating, into a real-time Q-PCR using the SYBRGreen (R) method, a primer set already used to study the genetic structure of soil fungal communities. To satisfy the real-time Q-PCR requirements to enhance the accuracy and reproducibility of the detection technique, this study focused on the 18S rRNA gene conserved regions. These regions are little affec…
Microbial community composition but not diversity changes along succession in arctic sand dunes
2017
The generality of increasing diversity of fungi and bacteria across arctic sand dune succession was tested. Microbial communities were examined by high-throughput sequencing of 16S rRNA genes (bacteria) and internal transcribed spacer (ITS) regions (fungi). We studied four microbial compartments (inside leaf, inside root, rhizosphere and bulk soil) and characterized microbes associated with a single plant species (Deschampsia flexuosa) across two sand dune successional stages (early and late). Bacterial richness increased across succession in bulk soil and leaf endosphere. In contrast, soil fungal richness remained constant while root endosphere fungal richness increased across succession. …