微生物学技术

Genetic markers have evolved over the years, increasing in their numbers and utility. Beginning with phenotypes such as smooth or wrinkled, the selection of genetic markers broadened to include blood group and histocompatibility antigens, and protein allotypes. Around 1980, DNA itse ...

Campylobacter spp. is one of the most commonly reported bacterial causes of acute diarrheal disease in humans throughout the world (1–3). The thermophilic Campylobacter jejuni, C. coli, C. lari, and C. upsaliensis are the most important species, with C. jejuni accounting for more than 95% of all the h ...

Since 1983, when Escherichia coli O157:H7 was first recognised as a cause of hemorrhagic colitis and hemolytic uremic syndrome (HUS), verotoxin-producing strains of E. coli (VTEC) have been identified as the cause of increasing numbers of cases of serious human illness (1,2). One of a number of lar ...

The rapid detection of foodborne pathogens such as Listeria monocytogenes requires ultrasensitive techniques that give measurable responses with low numbers of the target bacteria in food samples or enrichment cultures. Although a number of approaches are possible for detecti ...

Most Escherichia coli strains are harmless commensals in the human gut, but some strains are known to cause disease. The enterohemorrhagic E. coli (EHEC) strains of serotype O157:H7 causes hemorrhagic colitis, which may develop into life-threatening hemolytic uremic syndrome. Polym ...

One of the major problems in the food industry, particulary in dairy products, is the occasional presence of the pathogen Listeria monocytogenes, which has been associated with food-borne disease outbreaks (1). The association of listeriosis with the consumption of processed foods has p ...

During the last few years we have seen a public debate, involving every social statement, concerning food products and ingredients (1). The appearance in the market of the first food products, or organisms, which have been improved by recombinant DNA technologies (rDNA), has been received by soc ...

This chapter discusses the findings of many studies in food, clinical and environmental microbiology including approaches that have been used to overcome inhibition and facilitate amplification for detection and typing.

The chemical and physical environment of grape juice during fermentation, coupled with competition from indigenous yeast and bacteria, can present significant challenges to the growth of Saccharomyces cerevisiae. Individually or collectively, these factors may impact both y ...

Lactic acid bacteria (LAB) have been received much attention as bacteriocin producers. Antimicrobial proteins and peptides produced by bacteria, termed bacteriocin, are widely acknowledged to be important contributors to those organisms that survive dominate or die in microbi ...

Yeasts have been associated with foods since earliest times, both as beneficial agents and as major causes of spoilage and economic loss. Current losses to the food industry caused by yeast spoilage are estimated at several million pounds annually in the UK alone. As new food ingredients and new fo ...

Multilocus enzyme electrophoresis (MEE) is a method for characterizing organisms by the relative mobilities under electrophoresis of a large number of intracellular enzymes. These differences in mobility are directly related to mutations at the gene locus that cause amino acid sub ...

Strains tolerant to high temperatures, ethanol levels, and high concentrations of sugar are highly desirable for a fermentation process. The maintenance of a high degree of viability during the operation of a process, biomass storage, and pauses between batches is fundamental. Ferment ...

Flocculation is a naturally occurring process of reversible aggregation (cell-cell aggregation) of yeast cells (1), whereas flotation is defined as microbial enrichment in foams (2), which can be carried out either by induced flotation (with addition of flotation agents) or spontane ...

Microorganisms have been used intensively by the food industry as well as by pharmaceutical and other chemical industries. A great number of global companies take advantage of fermentation processes in the manufacture of a spectrum of useful products. Many of these processes involve yea ...

Chapter 38 deals with methods for hybridization of yeasts in different genera by protoplast fusion and for selection of hybrids by double-fluorescence staining and use of a micromanipulator. This chapter describes a similar but automated and rapid procedure for selection of hybrids; f ...

The characterization of yeasts at the strain level is of relevance from an industrial point of view because numerous yeast strains belong to the natural flora of commercial fermented foods and beverages (bakery products, cheeses, cold meats, wines, and beers) and take part in fermentation pr ...

There is great commercial interest in using immobilization technology for fermentation processes. Microbial immobilization is one of the novel methods in fermentation technology, especially important in the food and beverage industry, which allows the use of increased cell con ...

Cassava (Manihot esculenta) is a root crop of tropical American origin and is the fourth most important staple crop in the tropics. In the developing world, it is surpassed only by maize, rice, and sugarcane as a source of calories; cassava’s starchy roots produce more food energy per unit of land than any o ...

Isolation and enumeration of the microorganisms present in foods usually demands preliminary treatment of samples to release into a liquid medium those microorganisms present that may be included within the food. In a mixing procedure known as “stomaching,” the food sample (see Note 1) and d ...