Freeze-dried bacteria

BCG Cultures of live BCG cells in liquid or on solid media 1 Bacteria centrifuged from medium 2 Resuspension in stabilizer 3 Freeze-drying Viable count induction of sensitivity to tuberculin in guinea-pigs Exclusion of virulent mycobacteria absence of excessive dermal reactivity... 

Rapid-acting cytotoxin capable of producing either incapacitating or lethal effects. It is one of seven enterotoxins obtained from bacteria (Staphylococcus aureus). It is a white, fluffy solid that is water soluble and heat stable (not destroyed by cooking or freezing). Aqueous solutions are "probably stable." It resists chlorine used in municipal water systems. As a freeze-dried powder, it can be stored for more than a year. 

Bacteria can be stored as either liquids (e.g., organisms concentrated growth media) or powders (e.g., spores or freeze-dried mixtures of agent and growth media) and are easy to disperse. However, because they are living organisms and can be killed during the dispersal process, there are limitations to the methods that can be used. They can also be stored and... 

Figures 4.2.1 and 4.2.2 [4.9] show sorption isotherms 1, for such products which become less hygroscopic with increased temperature, or 2, for glucose, fats and oils which become more hygroscopic with increased temperature. Since freeze drying lowers aw values, the growth of bacteria, fungus and yeast below aw = 0.8 is reduced, or impossible. On the other hand, the Maillard reaction increases with decreasing aw up to a maximum at aw 0,6-0,7,...

Aryan Nations Member Caught Ordering Freeze-Dried Bacteria —... 

Munox products are freeze-dried bacteria that are regenerated on site. They are selected for their ability to degrade certain target contaminants. These bacteria are then introduced into whatever treatment scenario is being used at the site. 

Jabrait, A. 1969. Influence of coagulation and freeze-drying on survival of lactic acid bacteria in bioghurt. Lait 49, 520-532. (French)... 

Preservation of cell structure, food taste, and avoidance of thermal degradation are reasons for the removal of moisture from such materials by sublimation. The process is preceded by quick freezing which forms small crystals and thus minimum damage to cell walls, and is likely to destroy bacteria. Some of the materials that are being freeze dried commercially are listed in Table 19.9(b). 

Many modern pharmaceutical and biological products, e.g. blood derivatives, vaccines, cytostatic drugs, antibiotics, bacteria cultures but also consumer goods such as soluble coffee are freeze-dried to transform perishable substances into a form that can be stored and reconstituted to their almost original stale without loss of quality. 

DEV L34 - DIN EN ISO 11348-3 (1998) Water quality — Determination of the inhibitory effect of water samples on the light emission of Vibrio fischeri (Luminescent bacteria test) - Part 3 Method using freeze-dried bacteria. Beuth Verlag, Berlin, Germany. 

Procedure conducted under vacuum in which water is removed from bacteria (also known as freeze-drying). If the vacuum seal of the container is maintained and the bacteria are stored in the dark, they will remain viable indefinitely. Viable bacteria are activated by rehydration. Volume 1(1,2). 

Organisms which have been freeze-dried under vacuum (see above). Some bacteria, for example, can be lyophilized and stored for months at room temperature. They can then be rehydrated on demand and used to conduct bioassays. In the Microtox test, lyophilized Vibrio fischeri are stored in a freezer at -20° C and will be ready for use until the expiration date, which is provided with each batch of Bacterial Reagent. Volume 1(2,3). 

A method is described for treating diabetic hepatosis. Novel use is made of Jerusalem artichoke powder and live freeze-dried bifidus bacteria in an acid resistance capsule. 

Probiotics may be encapsulated in protein-based emulsions. Picot and Lacroix (2003) prepared microcapsules by emulsifying milkfat containing micronized skim milk powder (as a surrogate for freeze-dried bacteria) with heat denatured whey proteins and then spray drying. Incorporation rates of up to 58% milk fat and 29% skim milk... 

T. Nei, H. Souzu, and T. Araki, Effect of residual moisture content on the survival of freeze-dried bacteria during storage under various conditions. Cryobiology 2.-276-279 (1966). 

The stability of freeze-dried bacteria depends on the duration of incubation prior to freeze-drying, i.e., the condition of the bacterial cell [8-11]. The same holds true for viruses. Canine distemper virus, for example, shows some delicacy upon... 

The studies of Labuza et al. [18] were carried out on freeze-dried foods. However, we can suppose that the conclusions drawn are valid as well for those microorganisms (bacteria, viruses) that possess cell membranes with lipid layers that might be sensitive to oxidation. 

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