Colicin Concentrations Inhibit Growth of Escherichia coli O157:H7 In Vitro†

Escherichia coli O157:H7 is a virulent foodborne pathogen that causes severe human illness and inhabits the intestinal tract of food animals. Colicins are antimicrobial proteins produced by E. coli strains that inhibit or kill other E. coli. In the present study, the efficacy of three pore-forming colicins (E1, N, and A) were quantified in vitro against E. coli O157:H7 strains 86-24 and 933. Colicins E1 and N reduced the growth of E. coli O157:H7 strains, but the efficacy of each colicin varied among strains. Colicin E1 was more effective against both strains of E. coli O157:H7 than colicins A and N and reduced (P E. coliO157:H7 at concentrations E. coli O157:H7 in food animals.This article is from Journal of Food Protection 67 (2004): 2603–2607.</p

Migration Phenomenon in Food Packaging. Food-Package Interactions, Mechanisms, Types of Migrants, Testing and Relative Legislation-A Review

The development of convenient and low-cost packages, together with the increased consumer demands for safer products, have resulted in the conduction of extensive research and the publication of numerous studies related to the phenomenon of migration. The large number of synthetic materials used for the manufacture of packages makes the evaluation of the food-package interactions quite complicated. Different parameters such as the nature of the food of interest, the type of food-package contact, the time and temperature of contact, the packaging materials used, the properties of the migrating substances, as well as the amount of potential migrants contained in the packaging materials, can drastically affect the migration rate and extent. Due to the extreme variety of foods used, several food simulants have been suggested and applied for testing the migration phenomenon under various laboratory conditions. The use of many of those simulants is defined by national and international legislation. This review article covers the main migration phenomena, which are related to the most commonly used packaging materials. It is clearly demonstrated that the complexity of the migration phenomena requires more research to establish internationally accepted risk management procedures and standardised testing methods

Status of two Coreius species in the Three Gorges Reservoir, China

Dam construction alters natural flow regimes which, in turn, cause significant changes in fish communities during and after impoundment. The construction of the Three Gorges Reservoir, from impoundment of the Changjiang (Yangtze) River, China, may have affected native fish species. Thus, the status of two lotic freshwater fish species, Coreius heterodon and C. guichenoti, were monitored in the Three Gorges Reservoir, including fish abundance, individual composition, growth, condition, and mortality. Data on both species were gathered from upstream, midstream and downstream areas of the reservoir and, where available, from studies published before and after dam construction. Lower abundance, slower growth, a less diversified age structure, poorer fish condition (indicated by hepatosomatic index) and higher mortalities were recorded in sites nearest the dam compared with upstream areas. Furthermore, after final impoundment, individual Coreius species inhabiting the area changed, with young individuals becoming more abundant, while upstream of the reservoir the two Coreius species became smaller at a given age. The results show that the status of the two Coreius species was subject to dramatic changes after impoundmen