Aragonite crystallization in a sulfate-rich hypersaline wetland under dry Mediterranean climate (Laguna Honda, eastern Guadalquivir basin, S Spain).

This research investigates the influence of water composition, the presence of seasonal algal mats, detrital inputs and the activity of microorganisms on the crystallization of aragonite in the sediments deposited in the hypersaline Laguna Honda wetland (S of Spain). The high alkaline and hypersaline waters (pH > 9.2 and C.

Preliminary Study of the Bactericide Properties of Biodegradable Polymers (PLA) with Metal Additives for 3D Printing Applications.

Plastic is a highly used material in various sectors. Due to its plentiful availability in the environment, microorganism surface contamination is a risk. The aim of this work is to achieve bactericidal capacity in plastics that reduces the microorganism's colonization risk and, consequently, reduces the chances of having an infection with and bacteria.

Effect of High-Pressure Treatments on the Properties of Food Packaging Materials with or without Antimicrobials.

The aim of this research work was the comparative study of the different properties of interest in the case of plastic materials for food use before and after being subjected to treatment by high hydrostatic pressure (HHP) as well as the impact of additivation with antimicrobials. This method of food preservation is currently on the rise and is of great interest because it is possible to extend the shelf life of many foods without the need for the use of additives or thermal processing, as is the case with other preservation methods currently used. The effects of HHP treatment (680 MPa for 8 min) on plastic materials commonly used in the food industry were studied.

Genetic variation and evolution of the pathogenicity island of Enterococcus faecalis.

Enterococcus faecalis is a leading cause of nosocomial infections and is known for its ability to acquire and transfer virulence and antibiotic resistance determinants from other organisms. A 150-kb pathogenicity island (PAI) encoding several genes that contribute to pathogenesis was identified among antibiotic-resistant clinical isolates. In the current study, we examined the structure of the PAI in a collection of isolates from diverse sources in order to gain insight into its genesis and dynamics.

Comparative analysis of genetic diversity and incidence of virulence factors and antibiotic resistance among enterococcal populations from raw fruit and vegetable foods, water and soil, and clinical samples.

A comparative study was carried out among enterococci isolated from fruits and vegetable foods, water and soil, and clinical samples. Results indicate strong differences in the numbers of enterococcal species found in different environments as well as their abundance. While Enterococcus faecalis was clearly the predominant species in clinical samples, Enterococcus faecium predominated in vegetables, and it slightly outnumbered E.

Efficacy of enterocin AS-48 against bacilli in ready-to-eat vegetable soups and purees.

The broad-spectrum bacteriocin enterocin AS-48 was tested for biopreservation of ready-to-eat vegetable foods (soups and purees) against aerobic mesophilic endospore-forming bacteria. By adding AS-48 (10 microg/ml), Bacillus cereus LWL1 was completely inhibited in all six vegetable products tested (natural vegetable cream, asparagus cream, traditional soup, homemade-style traditional soup, vegetable soup, and vichyssoise) for up to 30 days at 6, 15, and 22 degrees C. A collection of strains isolated from spoiled purees showed slightly higher resistance to AS-48 in the order Paenibacillus sp.

Treatment of vegetable sauces with enterocin AS-48 alone or in combination with phenolic compounds to inhibit proliferation of Staphylococcus aureus.

The antimicrobial activity of enterocin AS-48 against Staphylococcus aureus was tested in vegetable sauces, alone and in combination with phenolic compounds. When added alone at 25 microg/ml, AS-48 inactivated all detectable staphylococci in napoletana and pesto sauces stored at 22 degrees C, but it only caused limited growth inhibition when these sauces were stored at 10 degrees C, as well as in other sauces such as carbonara and green sauce for fish. At 80 microg/ml, AS-48 eliminated all detectable staphylococci in napoletana, pesto, and green sauce for fish regardless of storage temperature, but it still had much more limited effect in carbonara sauce.

Stability of enterocin AS-48 in fruit and vegetable juices.

Enterocin AS-48 is a candidate bacteriocin for food biopreservation. Before addressing application of AS-48 to vegetable-based foods, the interaction between AS-48 and vegetable food components and the stability of AS-48 were studied. Enterocin AS-48 had variable interactions with fruit and vegetable juices, with complete, partial, or negligible loss of activity.

Inhibition of toxicogenic Bacillus cereus in rice-based foods by enterocin AS-48.

The antimicrobial effect of the broad-spectrum bacteriocin enterocin AS-48 against the toxicogenic psychrotrophic strain Bacillus cereus LWL1 has been investigated in a model food system consisting of boiled rice and in a commercial infant rice-based gruel dissolved in whole milk stored at temperatures of 37 degrees C, 15 degrees C and 6 degrees C. In food samples supplemented with enterocin AS-48 (in a concentration range of 20-35 mug/ml), viable cell counts decreased rapidly over incubation time, depending on the bacteriocin concentration, the temperature of incubation and the food sample. Enterotoxin production at 37 degrees C was also inhibited.