Bacteria removal

As mentioned in Chapter 3, DI water has now replaced distilled water for most laboratory purposes. PVC pipe, which is both inexpensive and easy to install, is normally employed to carry the water to points of usage. It is very important that the lines do not have dead legs where water is allowed to stand, since this could encourage bacterial growth. In cases where sterile water is needed, special steps must be taken. The water may be boiled, which also drives out dissolved gases, or ultraviolet radiation may be employed, a common method in the cosmetics industry. Membrane filters will also effectively remove bacteria. Laboratories needing sterile water often use two bacteria removal systems of... 

Giffel, M. C. T. and Horst, H. C. V. D. (2004). Comparison between bactofugation and microfiltration regarding efficiency of somatic cell and bacteria removal. Bull. Int. Dairy Fed. 389, 49-53. 

XII or XX) removed the capacities of each antiserum to react with all of the antigens, and absorption with each kind of bacteria removed the capacity of all the antisera to react with antigens of that kind of bacteria. 

Reactive Orange 96 Anaerobic culture of sulfate-reducing bacteria, methanogens, and fermentative bacteria Sulfate-reducing bacteria removed 95% of the dye in 40 h. Methane producing bacteria did not contribute in dye removal. Fermentative bacteria could remove only 30% of the dye in 90 h [186]... 

One third of it is used in water purification, where it serves as a coagulant, pH conditioner, and phosphate and bacteria remover. It reacts... 

Sweet wines, with potential for yeast refermentation, or wines with potential for malo-lactic fermentation, go through a membrane filtration prior to bottling. The membrane filters come in different porosities 0.65-p, pore size is used most commonly when 100 percent yeast removal is desired, and 0.45-p, pore size is used for malo-lactic bacteria removal. Proper sterilization of bottling equipment downstream of the membrane filter is essential to maintain the yeast- or bacteria-free nature of the wine after filtration. 

Cell envelope (cell wall, outer membrane) Glutaraldehyde EDTA, other permeabilizers Cross-links proteins Gram-negative bacteria removal of Mg2+, release of some LPS... 

Other demonstration tests using alumina membranes with a mean pore diameter of about 1.4 pm and with a cocurrent flow of permeate (to maintain a constant transmembrane pressure, TMP) to process skimmed milk by the cold pasteurization process have witnessed a flux exceeding 7(X) L/hr-m and 99.7% bacteria removal [Malmberg and... 

Merin and Daufin [44] and Bhave [3] present a comprehensive review of the field, the main use of ceramic membranes being protein concentration by micro-or ultra-filtration and bacteria removal by microfiltration. For the latter the Bactocatch process, as described by Gillot et al. [47], Merin and Daufin [44] and Bhave [3] forms an important example. At an average flux of 7001/m h 99.7% of the bacteria are withheld without retaining the proteins. 

Bacteria removal from water via microfiltration - a mechanical sieving process driven by pressure differential. ... 

Table 12 shows the typical LRV values obtained using a polymeric and ceramic microfilter. Sterile filtration requires 100% bacteria retention by the membrane, whereas in many industrial bacteria removal applications the presence of a small quantity of bacteria in the filtrate may be acceptable. For example, drinking water obtained by microfiltration may contain nominal counts of bacteria in the filtrate which is then treated with a disinfectant such as chlorine or ozone. The use of ceramic filters may allow the user to combine the sterile filtration with steam sterilization in a single operation. This process can be repeated many times without changing filters due to their long service life (5 years or longer). 

Pall. D. B.. and Kimbauer, E, A. (1978). Bacteria removal prediction in membrane niters. In Proceedings of 52nd Colloid and Surface Science Symposium, University of Tennessee, Knoxville, Tennessee. 

Coagulation and sedimentation, used to treat surface water sources, greatly reduce indicator bacteria. Removal rates for E. coli and coliforms by aluminium sulphate range from 75 to 99.4% [16]. 

It was pointed out above that nitrite is usually present only in traces in arable soils. We have always explained this by saying that nitrate-forming bacteria remove it as fast as formed. In the light of the newer knowledge we may need to emphasize that there is both a biological and a chemical demand for each bit of nitrite as the Nitrosomonas bacteria produce it. 

For the test procedure, subjects hands were contaminated with the test organisms. Subjects treated their hands once with a liquid soap product. They washed their hands for 30 seconds and rinsed for 15 seconds. Afterward, hands were sampled three times using the plastic bag sampling procedure. Aliquots of the three sampling solutions were diluted, plated, and incubated. Following incubation, the number of CFUs was enumerated. Antibacterial activity was determined by comparing the number of bacteria removed from the hands after washing once with the test product to the number of bacteria removed from unwashed hands. 

Urease Bacteria Removal of urea in alcohoUc beverages... 

Dilute the suspension of bacteria removed form the catheter, plate on trypticase soy agar, and incubate at 37 °C for colony counting. 

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