Search results for "Cereus"
showing 10 items of 40 documents
The BIOSAFEPAPER project for in vitro toxicity assessments: preparation, detailed chemical characterisation and testing of extracts from paper and bo…
2008
International audience; Nineteen food contact papers and boards and one non-food contact board were extracted following test protocols developed within European Union funded project BIOSAFEPAPER. The extraction media were either hot or cold water, 95% ethanol or Tenax, according to the end use of the sample. The extractable dry matter content of the samples varied from 1200 to 11,800 mg/kg (0.8-35.5 mg/dm2). According to GC-MS the main substances extracted into water were pulp-derived natural products such as fatty acids, resin acids, natural wood sterols and alkanols. Substances extracted into ethanol particularly, were diisopropylnaphthalenes, alkanes and phthalic acid esters. The non-foo…
Volatile constituents of Dianthus rupicola Biv. from Sicily: activity against microorganisms affecting cellulosic objects.
2014
Dianthus rupicola Biv. (cliffs carnation) is a camephytic, suffruticous, perennial plant growing up to 40 cm high. The plant is widespread in Sicily and neighbouring islands (Egadi, Lampedusa, Lipari) and in some areas of southern Italy. GC and GC-MS analyses of the essential oil distilled from the flowers showed the presence of 66 components. Its composition is characterised by the high content of thymol and carvacrol derivatives. A good antibacterial activity against Bacillus cereus and Bacillussubtilis, both infesting cellulosic historical material, was shown, whereas the antioxidant capacity was determined to be quite poor.
Laundry detergent compatibility of the alkaline protease from Bacillus cereus.
2004
The endogenous protease activity in various commercially available laundry detergents of international companies was studied. The maximum protease activity was found at 50 degrees C in pH range 10.5-11.0 in all the tested laundry detergents. The endogenous protease activity in the tested detergents retained up to 70% on incubation at 40 degrees C for 1 h, whereas less than 30% activity was only found on incubation at 50 degrees C for 1 h. The alkaline protease from an alkalophilic strain of Bacillus cereus was studied for its compatibility in commercial detergents. The cell free fermented broth from shake flask culture of the organism showed maximum activity at pH 10.5 and 50 degrees C. The…
Assessment of microbial quality of commercial and home-made tiger-nut beverages
2012
Aims: We aimed to assess the microbiological quality of Spanish commercial tiger-nut beverages as well as home-made samples collected from supermarkets, street vendors, juice bars and ice-cream parlours located in Valencia. Methods and Results: Microbiological analysis of 44 tiger-nut beverages samples were carried out according to International Standard Organization (ISO) norms and published works which included the total viable count, Enterobacteriaceae, Escherichia coli, Staphylococcus aureus, Salmonella, Bacillus cereus, yeasts, moulds, Yersinia enterocolitca, Clostridium perfringens, Vibrio spp. and Listeria monocytogenes. The obtained results indicated that all the commercial sample…
Effect of heat activation and inactivation conditions on germination and thermal resistance parameters of Bacillus cereus spores.
2001
The effect of isothermal and non-isothermal heat activation on germination and thermoresistance of two strains of Bacillus cereus spores was studied. Results indicated that the germination after isothermal activation was lower than after non-isothermal heating. The activation rate affected the z value, which increased with faster heating rates. For each temperature and inactivation rate, the non-isothermal activation at rate of 2 degrees C/min resulted in larger D values (D90 = 4.70 min) than isothermal activation (D90 = 4.04 min). The two mathematical equations used to analyse non-isothermal data produced similar predicted D and z values, nevertheless the Hayakawa equation modified in this…
Structure–activity relationship of sphingomyelin analogs with sphingomyelinase from Bacillus cereus
2012
AbstractThe aim of this study was to examine how structural properties of different sphingomyelin (SM) analogs affected their substrate properties with sphingomyelinase (SMase) from Bacillus cereus. Using molecular docking and dynamics simulations (for SMase–SM complex), we then attempted to explain the relationship between SM structure and enzyme activity. With both micellar and monolayer substrates, 3O-methylated SM was found not to be degraded by the SMase. 2N-methylated SM was a substrate, but was degraded at about half the rate of its 2NH–SM control. PhytoPSM was readily hydrolyzed by the enzyme. PSM lacking one methyl in the phosphocholine head group was a good substrate, but PSM lack…
Empirical model building based on Weibull distribution to describe the joint effect of pH and temperature on the thermal resistance of Bacillus cereu…
2002
Abstract A mathematical model based on Weibull parameters was built to describe the joint effect of temperature and pH on thermal inactivation of Bacillus cereus spores (strain INRA TZ415). The effect of these factors on Weibull model parameters ( β , 1/ α ) was also studied. Heat inactivation tests were carried out in acidified carrot broth as vegetable substrate, following a full factorial design at four levels for temperature (80, 85, 90 and 95 °C) and pH (6.2, 5.8, 5.2 and 4.7). The Weibull distribution model provided good individual fits for the different combinations of temperature–pH tested, with discrepancy factors, D f , coming close to 25% for most cases. The temperature and pH di…
Risk of Bacillus cereus and Pseudomonas aeruginosa nosocomial infections in a Burns Centre: the microbiological monitoring of water supplies for a pr…
1995
This paper reports on an extensive epidemiological survey of the microbiological monitoring of the environment, staff, and patients in the Intensive Care Unit of the Palermo Bums Centre (Italy). The aim of the survey was to evaluate the presence and distribution of environmental sources of pathogens and opportunistic bacterial agents of nosocomial infection in immunocompromised hosts. Strains collected from air, tap water, and medical and nursing staff were compared with strains isolated from burn patients in order to study the potential transmission route of bacteria. The results showed environmental strains presenting a profile identical to that of the clinical strains, suggesting a link …
Iron oxide superparamagnetic nanocarriers bearing amphiphilic N-heterocyclic choline analogues as potential antimicrobial agents
2015
Magnetic nanoparticles represent an advanced tool in biomedicine because they can be simultaneously functionalized and guided using a magnetic field. Iron oxide magnetic nanoparticles precoated with oleic acid and bearing novel antimicrobial N-heterocyclic choline analogues, namely O-, N- and O,N-bis-undecyl-substituted N-(2-hydroxyethyl)-1,2,3,4-tetrahydroisoquinolinium derivatives, have been obtained as potential biomedical agents for drug delivery and antimicrobial therapy. Structural and size determinations for the novel synthesized magnetic nanosystems were carried out based upon magnetogranulometry, dynamic light-scattering measurements and X-ray diffraction analysis. The most expecte…
Garšvielu un garšaugu mikrobioloģiskais piesārņojums
2015
Pētīts garšvielu un garšaugu mikrobioloģiskais piesārņojums 20 dažādās garšvielās un garšaugos, kuri veidoja 60 paraugus. Paraugi iegūti no lielveikala ķēdes, tirgus. Tika noteikta Bacillus cereus, Clostridium perfringens, pelējumsēņu koncentrācija, Escherichia coli klātbūtne, B. cereus vemšanas toksīnu un diarejas toksīnus kodējošie gēni, kā arī hblC toksīnu producējošie B. cereus celmi. Veikta pelējumsēņu ģinšu identifikācija. Pētīta ūdens aktivitāte. Mērķis bija noteikt no dažādām tirdzniecības vietām iegūto garšvielu un garšaugu mikrobioloģisko piesārņojumu. Konstatēts, ka mikrobioloģiski vispiesārņotākie ir melnie pipari ar vislielāko B. cereus, C. perfringens koncentrāciju un ķimenes …