Search results for " Bacillus"
showing 10 items of 25 documents
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.
Bacillus thuringiensis treatment modulate the HSP70 expression in larva and adult brain of Rhynchophorus ferrugineus
2013
To study the pathogen-host relationship, we used the model of the entomopathogenic bacterium Bacillus thuringiensis (Bt) and Rhynchophorus ferrugineus, a quarantine pest that attacks palm trees. In particular, we focused on the Bt stress-induced infections. We studied the effect of Bt on larval and adult growth, and on the expression of the heat shock proteins (HSPs), rapidly synthesized in the cell after exposure to stress including pathogens. Bt has negative effects on larval and adult growth, on total hemocytes counts and on the hemocyte type. HSP70 was evaluated in the supernatant of the brain lysate obtained from larvae and adults fed with sublethal doses of Bt. HSP70 expression was mo…
Bacillus thuringiensis treatment alters larval growth, hemocytes and modulation of Hsp70 in Rhynchophorus ferrugineus
2011
To study the pathogen-host relationship, we used the model of the entomopathogenic bacterium Bacillus thuringiensis (Bt) and Rhynchophorus ferrugineus, a quarantine pest that attacks the palm trees. In particular, we focused on the Bt stress-induced infections. We studied the effect of Bt on larval growth, on hemocytes and on the expression of the heat shock proteins (Hsp70). HSPs are rapidly synthesized in the cells after a stress exposition including pathogens. The Hsp70 was evaluated in the supernatant of the hemocyte lysate (HLS) obtained from larvae fed with Bt. This is the first time that the presence of Hsp70 has been recorded in R. ferrugineus. Bt has negative effects on larval grow…
Use of biorational insecticides for the control of Tuta absoluta (Meyrick) infestations on open field tomato
2012
Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), the tomato leaf miner, is one of the most devastating pests affecting tomato crops in Italy. Management of T. absoluta was assessed in open-field tests using three biorational insecticides, Azadirachtin, Bacillus thuringiensis var. kurstaki, and Beauveria bassiana, and a combination of three synthetic insecticides, Emamectin, Indoxacarb and Metaflumizone, as a control treatment. Our results showed that only the combination of Azadirachtin – B. thuringiensis was able to reduce the impact of tomato leaf miner on the fruit’s marketable production similarly to the control treatment. This finding suggests that biorational insecticides are a goo…
Interactions between Bacillus amyloliquefaciens AG1 and Aspergillus spp. contaminating food and feedstuffs
2022
Aspergillus is a widespread fungal genus contaminating and degrading food and feeds mostly during storage. Some species can also produce carcinogenic mycotoxins harmful for human and animal health. In this study, Bacillus amyloliquefaciens AG1 (BaAG1), active against fungal pathogens was evaluated by in vitro tests against seven Aspergillus species belonging to six Aspergillus sections. After 7 days of incubation at 25°C, mycelial growth of all fungal species was reduced from 46.53% to 60.92%, compared to the controls. The inhibitory effect of BaAG1 cell-free culture filtrate was tested by turbidimetric measurements by using ScanReady P-800 that allow the automatic and continuous monitoring…
In vivo modulation of Bacillus thuringiensis (commercial form) on Holothuria tubulosa immune defense mechanisms
2010
In invertebrates, cellular and humoral components are evolved to maintain their homeostais and integrity. Both these components respond to different non-self such as microorganisms, vertebrate erythrocytes and foreign proteins. The aim of this research was to study the possible modulating effects of Bacillus thuringiensis (Bt) in a commercial and vegetative form on the immune response of the echinoderm, sea cucumber Holothuria tubulosa. Bt is one of the most used biopesticides worldwide, covering the 90% of the organic market. Sicily is a region vocated to biological control and agricultural area are often closed to the coastal area. Investigate the effect of biopesticides on other non targ…
Eco-physiological response of two marine bivalves to acute exposition to commercial Bt-based pesticide
2013
Microbial products based on the entomopathogenic bacterium Bacillus thuringiensis (Bt) are among the most common biopesticides used worldwide to suppress insect pests in forests, horticulture and agricultural crops. Some of the effects of commercial Bt have been recorded for terrestrial and freshwater non-target organisms but little research is available on marine fauna. Nevertheless, due to the contiguity of agro-ecosystems and coastal habitats, marine fauna may be highly influenced by this control method. We studied the effect of a commercial Bt product on the physiological and ecological responses and the energy budget of two of the most frequent marine intertidal bivalves in the Mediter…
Uso del tonometro e rischio infettivo ; valutazione dell'efficacia di differenziali tipi di disinfettanti.
2006
Obiettivo: valutare e confrontare l’efficacia dei più comuni tipi di disinfettanti per la disinfezione dei coni tonometrici e trarre alcune indicazioni sulla applicabilità alla realtà clinico-diagnostica in campo oftalmologico. Materiali e metodi: coni tonometrici monouso sterili, previamente contaminati con ceppi standard di Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa e Candida albicans sono stati testati, dopo semplice detersione o disinfezione con acqua ossigenata al 3%, benzalconio cloruro allo 0.5%, Minuten wipes (Alpro® ), Pantasept® allo 0.5% secondo le linee guida del CDC di Atlanta. Risultati: la semplice detersione è stata inefficace contro tutte le specie tes…
Study of Bacillus subtilis spore's : characterication of stuctures implied in its resistance
2013
The bacterial spore is a multilayer microbial form which is extremely resistant to environmental perturbations. This resistance is especially due to its unique structure which is particularly compact and weakly permeable. This work aims to identify and characterize the spore structures involved in these properties. Overall investigation methods, such as NMR and fluorescence anisotropy, have shown that the cortex of Bacillus subtilis spores is modified by temperature for level similar to that of the activation of germination. This will result in changes to the access to the inner membrane. A tool at the spore’s scale, the fluorescence lifetime imaging microscopy (FLIM) in conjunction with th…
Estudio de una superfamilia de genes de respuesta a patógenos (repat) en insectos
2012
El intestino de los insectos es una de las principales vías de entrada de entomopatógenos. Con el fin de minimizar los efectos negativos de los patógenos, el intestino de los insectos posee diferentes mecanismos: síntesis de péptidos antimicrobianos, producción de especies reactivas de oxígeno, activación de los sistemas de reparación y detoxificación, melanización, fagocitosis, apoptosis y la renovación celular, entre otros. Estudios de expresión tras la exposición a diferentes patógenos han mostrado cómo la expresión de ciertos genes varía en el intestino tras la infección. Previamente a la realización de esta tesis, se identificó, en el lepidóptero Spodoptera exigua, una familia de genes…