Spores sampling

Is the nominal radiation dose sufficient to destroy B. pumilus spore samples at a relatively high concentration (e.g., 108 spores per ml or per strip) using a minimum load of product (minimum density) ... 

Fig. 19.5. (A) Representative SER spectra of three Gram-positive live (L) and two formalin-killed (K) Bacillus spore samples and the Gram-negative Pantoea agglom-erans (B) PCA plot showing discrimination and (C) dendrogam showing classification between the samples (reprinted with permission from [100]. Copyright (2008) The Society for Applied Spectroscopy)...

Real-time PCR was also performed by on-chip thermal cycling for the detection of Hantavirus, HIV, orthopoxviruses (266-281 bp), Borrelia burgdorferi, human (3-actin (294 bp), and the human complement C6 gene (73 bp) [944]. In another report, real-time PCR was performed for DNA extracted from Bacillus subtilis in a plastic microfluidic cassette. The spore samples (lOVmL) were sampled, filtered, and sonicated in the presence of 6-pm glass beads for spore disruption to release the DNA [945],... 

Exposures associated with sterilized product degassing unloading, transfer, storage, and spore sample removal. 

To demonstrate the robnstness of Principal Component Analysis (PCA) classification and identification methods when applied to the IR spectra of different spore types, transmission FTIR spectral libraries were generated for three different spore strains (BG, BA, and BS) and classification models were developed based upon Mahalanobis Distance by PCA with Residnals (MD/PCA/R) statistical methods using PLSplns IQ (Thermo Electron) chemometric software. Figme 5 shows a representative IR spectrum of a BG spore sample recorded in transmission, which in many respects is representative of all spore types dne to their nearly identical compositions at the molecnlar level. 

Spore suspensions of B. subtilis (strain ATCC 6633) and Bacillus thuringiensis (strain ATCC 29730) were obtained from Raven Biological Laboratories Inc. (Omaha, NE). The spore samples were labeled with Syto 11 (Molecular Probes, Eugene, OR) dyes that labels the spores fluorescent green (excitation/emission 508/527 nm). llie samples were dyed as received, without... 

Calderon C, Ward E, Freeman J, McCartney A (2002) Detection of airborne fungal spores sampled by rotating-arm and Hirst-type spore traps using polymerase chain reaction assays. J Aerosol Sci 33 283... 

Thermoduric, Thermophilic, andPsychrophihc Bacteria. Thermoduric bacteria survive but do not grow at pasteurization temperatures. They are largely non spore-forming, heat-resistant types that develop on surfaces of unclean equipment. These bacteria are determined by subjecting a sample to laboratory pasteurization and examining it by the agar plate method. 

A culture of Bacillus polymyxa in a tube with Trypticase soybean broth was incubated overnight at 25°C. 5 ml of this culture was transferred to 100 ml of the tank medium in a 500 ml Erlenmeyer flask which was incubated for 48 hours at room temperature. This 100 ml culture served as inoculum for one tank. During the course of fermentation the medium was aerated at the rate of 0.3 volume of air per volume of mash per minute. The temperature was maintained at about 27 C. Samples of mash were taken every 8 hours in order to determine pH and the presence of contaminants and spores. After 88 hours of fermentation the pH was about 6.3 and an assay using Escherichia coll showed the presence of 1,200 units of polymyxin per cubic centimeter. The polymyxin was extracted and purified by removing the mycelia, adsorbing the active principle on charcoal and eluting with acidic methanol. 

The inoculate was prepared in 250 ml flasks containing 100 ml of growth medium, which is inoculated with 10 ml of spore suspension. The mixture was shaken at 250 rpm and the temperature was controlled at 26 °C for 48 h. Then, 110 ml of resulting mycelia suspension is used to inoculate a 1000 ml broth in the airlift fermenter. The sterilised media are slowly pumped into the bioreactor at a flow rate of about lOOmlh-1 until 2 1 working volume is fully utilised. Aeration rates of 0.5, 1 and 2vvm (1,2 and 4 1 air/min) are used.6,7 Samples were taken at 24 hour intervals and evaluated for biomass, sugars and antibiotic concentrations. 

Fungal spores or mycelium may be added to the solution under test. At selected time intervals, samples can be subcultured into suitable media and the presence or absence of growth noted after incubation. A quantitative assessment similar to that described for bactericidal activity (section 3.2, Table 11.3) can also be undertaken. 

Experiments in 500 ml Erlenmeyer flasks and Fernbach flasks contained 200 ml and 1 L of EPl and EP2 medium respectively. Inocuia added to these cultures was 2 ml of spore suspension (5.0 optical density at 540 nm) for each 100 ml EP medium. All cultures were grown at 37°C in a shaking incubator (New Brunswik Sci. Co., USA), at 200 rpm. Then 10 ml of sample were withdrawn each 24 h during fermentation and immediately filtered through Millipore membranes of 0.45 pm pore size these cell-free filtrates were used for enzymatic assays and extracellular protein determinations by the Lowry method (14). Experiments in the 14 L fermentor (Microgen Fermentor New Brunswik Sci. Co., USA) were carried with lOL of fermentation medium EP2 and inoculum added was IL of mycelium grown 24 h in... 

The experiments were intended to clarify the question as to whether transmission of spores from Mars to Earth could be feasible. To do this, a Mars meteorite was simulated, i.e., the spores were mixed with powdered rock and the mixture pressed together to give a small cube about 1 cm3 in size. The spore concentration was about the same as in normal soil on Earth. The samples were in orbit for around 2 weeks, and their survival ability was determined on their return to Earth, compared with the corresponding samples which had been left on Earth (control experiment). 

Virulent bacteria Food and environmental samples 1000 cells mL-1 (Escherichia coll 0157, Salmonella, Bacillus anthrax spores)... 

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