Bacterial inoculum

The Kelsey-Sykes (KS) test. Having regard to the many disadvantages alleged against the RW and CM tests, attempts were made and published in the early 1960s to find improved test methods. The foundations for the new test were laid by Kelsey et al. in 1965, and with the collaboration of the late G. Sykes and ofisobel M. Maurer, the Kelsey-Sykes test was evolved. This test embodied several principles. Firstly, it was a capacity test. Here a bacterial inoculum was added to the disinfectant in three successive lots at 0, 1 and 5 minutes. This is the principle of a capacity test where the capacity or lack of capacity ofthe disinfectant to destroy successive additions of a bacterial culture is tested. 

A sample of a standard calcium carbonate slurry was received from a large manufacturer in the USA. This sample was subjected to preservative efficacy testing according to the ASTM E 723-91 test protocol. Preservative treated samples were inoculated with a mixed bacterial inoculum containing organisms with a known tolerance or resistance to BIT (l,2-Benzisothiazolin-3-one). Untreated controls were included for reference purposes. The test procedure is outlined below. 

Holding the mice vertically, deliver a 40 xl volume of bacterial inoculum to the nostrils to induce aspiration pneumonia. Inoculate control mice with sterile PBS. 

Figure 9.10 is a plot of steepwater composition taken from successive steeps across a ten steep, continuous-flow battery in 1950 when process water used for steep acid provided a rich bacterial inoculum. Today s continuous countercurrent steep batteries have approximately the same types of changes in every property except relative... 

Abbondanzi F, Cachada A, Campisi T, et al. (2003) Optimisation of a microbial bioassay for contaminated soil monitoring Bacterial inoculum standardisation and comparison with Microtox((R)) assay. Chemosphere 53(8) 889-897. 

The size of the bacterial inoculum and the number and types of bacterial species present in intraabdominal infections influence patient outcome. The combination of aerobic and anaerobic organisms appears to increase the severity of infection greatly. In animal smdies, combinations of aerobic and anaerobic bacteria were much more lethal than infections caused by aerobes or anaerobes alone. 

The concentration of bacterial inoculum giving suitable results may be determined using direct microscopic count, viable counts, turbidity tubes, or spectrophotometric methods. These methods may not give the same result so one standard method should be used (see Chapter 5). Spectrophotometric methods may produce varying results between species due to differences in the size of the cells and hence their light scattering properties. Each species should therefore be checked. 

X 10 bacteria/mL for both organisms, but this needs to be determined for every organism by plating serial dilutions of the bacterial inoculum on appropriate medium before hand. Determining the bacterial inoculum is essential to calculate the multiplicity of infection (MOI) to be used. Theoretical MOIs of 25 and 50 are used for B. abortus and F. tularensis, respectively see Note 5). 

Biodegradation is a strongly time-dependent phenomenon, and the period allowed for acclimation of the microbes to a substrate significantly affects the experimental results. The rate of adaptation is influenced by the dosage, either continuous or intermittent, of the xenobiotic. Because the concentrations of compounds in laboratory tests are generally much higher than those in the environment, toxicity towards the bacterial inoculum may result in... 

PEC disinfection rate is inversely proportional to bacterial concentration in water samples. Total inactivation may be achieved in relatively short treatment time (i.e. within approximately 15 min) when bacterial inoculum contains 10 ... 

If the scale is used with the API Rapid GH system to prepare the bacterial inoculum, it is best to make McFarland Scale 1 to 4 in order to compare densities of the inoculum and determine the specific dilutions required. 

Standardised test methods, such as ISO 11348 [59], could be used for aqueous samples and elutriates. Light-emitting marine bacteria, such as Vibrio fischeri or Photobacterium sp., are used. A defined bacterial inoculum is added to the sample solutions and the change of bioluminescence intensity is measured over a period of 30 min. Ready to use test kits, e.g., LumisTox (Dr. Lange) or ToxAlert (Merck) are available and comply with all the requirements defined in the standard methods. 

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