Search results for " Microbial"
showing 10 items of 340 documents
Microbiological and safety evaluation of green table olives marketed in Italy
2011
The microbiological and safety conditions of green table olives sold on the Italian market were evaluated on 40 samples, 20 loose and 20 packed in containers, purchased at street markets and supermarkets. The olives were analyzed for microflora and food safety indices, and for aflatoxin B1 and ochratoxin A occurrence, and the results showed acceptable security. There was wide heterogeneity in the microflora, the numerical values being in relation to the olive type. The microbial population was dominated by the yeasts and lactic bacteria responsible for the fermentation process, and their numbers, together with the metabolic activity, led to conditions unfavorable for the development of path…
Tyramine and phenylethylamine production among lactic acid bacteria isolated from wine.
2007
The ability of wine lactic acid bacteria to produce tyramine and phenylethylamine was investigated by biochemical and genetic methods. An easy and accurate plate medium was developed to detect tyramine-producer strains, and a specific PCR assay that detects the presence of tdc gene was employed. All strains possessing the tdc gene were shown to produce tyramine and phenylethylamine. Wines containing high quantities of tyramine and phenylethylamine were found to contain Lactobacillus brevis or Lactobacillus hilgardii. The main tyramine producer was L. brevis. The ability to produce tyramine was absent or infrequent in the rest of the analysed wine species.
Antibacterial activity of flavonoids and phenylpropanoids from Marrubium globosum ssp. libanoticum.
2006
Marrubium globosum Montbr. et Auch. ex Benth. ssp. libanoticum Boiss. (Lamiaceae) is a medicinal plant used for the treatment of inflammatory diseases, asthma, coughs and other pulmonary and urinary problems. The goal of our study was to assess the biological activity of M. globosum testing the methanol extract of aerial parts for its antibacterial activity against bacteria known to cause respiratory, gastrointestinal, skin and urinary disorders; the extract showed antibacterial effects against all the strains of bacteria used. A purification of this active extract showed the presence, as main constituents, of verbascoside, isorhamnetin 3-O-beta-D-rutinoside, quercetin 3-O-beta-D-rutinoside…
Inhibitors of antibiotic resistance mechanisms: clinical applications and future perspectives
2020
Bacterial strains responsible for antibiotic resistant infections are increasing in an alarming way and the evolution of resistance mechanisms seems to be unstoppable. In the past decade, many efforts have been made in order to counteract this phenomenon but very few compounds have reached clinical trials. The development of new classes of antibiotics able to overcome the main bacterial drug resistance mechanisms is urgently required to counter the imminent danger of a postantibiotic era.
Synthesis and antifungal activity of new N-isoxazolyl-2-iodobenzamides
1999
N-Isoxazolyl-2-iodobenzamides 3 and 9, with a benodanil-like structure, were synthesized by refluxing in acetic acid the corresponding benzotriazinones 2 and 8 with potassium iodide for 1 h with the aim to ascertain if they were active as fungicides against Phytophthora citricola Saw., Botrytis cinerea Pers., Rhizoctonia sp. and Alternaria sp. Among the tested iodo derivatives, compounds 3b and 9a possess interesting activities against the aforesaid fungal strains in several cases similar to that of benodanil I taken as reference drug.
Role of yeasts in table olive production
2008
Table olives are a traditional fermented vegetable of the Mediterranean countries, but their production and consumption are now spread all around the world. Yeasts can play a double role in this food. They are present throughout the fermentative process and it is generally accepted that they can produce compounds with important organoleptic attributes determining the quality and flavour of the final product. However, yeasts can also be spoilage microorganisms in olive fermentation/storage and packing causing gas pockets, swollen containers, cloudy brines and off-flavours and off-odours. Candida boidinii, Debaryomyces hansenii, Pichia anomala, P. membranifaciens, Rhodotorula glutinis and Sac…
Hygienic characteristics of radishes grown in soil contaminated with Stenotrophomonas maltophilia
2015
Background: Stenotrophomonas maltophilia is a plant growth-promoter. This bacterium is also implicated in human diseases. Thus, after the use of this bacterium in agriculture, the safety of the final products has to be verified. Due to the ubiquitous presence of S. maltophilia in soil, in this study a massive contamination was simulated to evaluate the growth and safety of Raphanus sativus L.. Results: Different inoculums and soil treatment conditions were tested. Soils were analysed weekly and the radishes at harvest for their microbial loads and presence/persistence of S. maltophilia LMG 6606. The concentration of the bacterium added in the different trials decreased during the first week…
Cathodic abatement of Cr(VI) in water by microbial reverse-electrodialysis cells
2015
Abstract For the first time a microbial reverse electrodialysis cell (MRC) was used for the treatment of water contaminated by Cr(VI). It has been recently shown that both inorganic and organic pollutants can be removed by reverse electrodialysis processes (RED) using water with different salinity without the supply of electric energy. However, a high number of membrane pairs is usually necessary for the treatment of wastewater by RED. Here, it was showed that a lower number of membranes can be used by the utilization of a MRC (i.e., a RED cell with a biotic anode) for such purposes. Indeed, the abatement of Cr(VI), chosen as model pollutant, was successfully achieved by cathodic reduction …
Mould germination: data treatment and modelling.
2006
Abstract The objectives of this study were i/ to examine germination data sets over a range of environmental conditions (water activity, temperature) for eight food spoilage moulds, ii/ to compare the ability of the Gompertz equation and logistic function to fit the experimental plots, iii/ to simulate germination by assessing various distributions of the latent period for germination amongst a population of spores. Data sets (percentage germination, P (%), versus time, t) of Aspergillus carbonarius, Aspergillus ochraceus, Fusarium verticillioides, Fusarium proliferatum, Gibberella zeae, Mucor racemosus, Penicillium chrysogenum and Penicillium verrucosum were analysed. No correlation, or re…
Growth potential of Listeria monocytogenes strains in mixed ready-to-eat salads
2009
In this study, a microbiological challenge test in three artificially contaminated retail mixed mayonnaise-based ready-to-eat salads stored at refrigerator temperatures (3°C and 7°C) for 48h was carried out. Shrimp-tomato salad, smoked ham salad and garlic cheese salad were separately contaminated by a suspension of particular Listeria monocytogenes strains. The number of L. monocytogenes, Enterobacteriaceae, staphylococci and total plate count (CFU/g) was determined. Listeria monocytogenes growth potential in the salads was calculated and evaluated. A significant increase in total plate count and L. monocytogenes count throughout storage of all three investigated salads was found. Enteroba…