Microorganisms collections

Cumene is expected to exist almost entirely in the vapor phase in the atmosphere (13). In water, mixed cultures of microorganisms collected from various locations and depths in the Atiantic Ocean were all found to be capable of degrading cumene (14). A number of studies have examined the aerobic degradation of cumene in seawater and in groundwater (15,16). The results indicate that cumene would normally be naturally degraded to below detectable limits within a week to ten days. Cumene is tightly adsorbed by soil and is not significantly mobile in soil (17). 

Unique Extremophilic Microorganisms, Collection of Unique Microbial Cultures, Russian Academy of Sciences (UNIQEM). 

Periodically, strains of microorganisms collected from the manufacturing environment should be used as challenge organisms. 

Total Bacteria Count The TBC is determine by directly counting the actual number of microorganisms collected on a filter after it is used to filter a sample of the water in question.5 The sample is stained with acridine orange and viewed with an epi-illuminated fluorescent microscope. This technique is more accurate and quicker than the culture technique, but is not as practical for field work. 

Swabbing is a technique in which a surface is lightly scrubbed with a moistened collector (swab), most often a cotton or alginate bud. The swab is then rolled over the surface of an agar plate. Alternatively the swab may be immersed in a liquid aiKl agitated to suspend the microorganisms collected. The liquid is then plated, or passed through a sterile membrane filter and plated on a nutrient medium. 

A DDT is a toxin still found in the fatty tissues of some animals. DDT was transported into our lakes and streams as runoff from agricultural operations where it was originally used several years ago as an insecticide. In the lakes and streams it did not dissolve to any great extent it collected in the lake and stream bottoms. It entered the bodies of animals via fatty tissues in their diet microorganisms collected the DDT, the fish ate the microorganisms, and... 

A seed culture of S. cerevisiae ATCC 24860 (American Type Culture Collection, Manassas, VA, USA) was grown in a media of 5g glucose, and 0.5 g yeast extract, respectively, 1.5 g KH2P04 and 2.25 g Na2P04 phosphate buffer up to a total volume of distilled water, 500 ml. The media was sterilised at 121 °C for 15 min. The stock culture of the microorganisms was transferred to the broth media for preparation of seed culture. 

Measure the optical cell density of S. cerevisiae at a wavelength of 520 nm. Try to collect data based on information required in Table 10.1. Draw a growth curve based on incubation time and cell dry weight. The cell concentration is an indication of microorganism growth. A standard calibration curve is needed before any actual experiment. 

To prevent dust from collecting, all ledges, doors and windows should fit flush with walls. Doors should be well fitting to reduce the entry of microorganisms, except where... 

Brief notes are added on phosphorofluoridates even though their destruction by microbial activity— though clearly possible—is limited by their toxicity to the requisite microorganisms. One of the motivations for their inclusion is the fact that the hydrolytic enzyme(s) responsible for defluorination—organophosphorus acid anhydrase (OPA)—is widespread, and is found in a number of bacteria (Landis and DeFrank 1990). The microbial hydrolysis of organophosphorus pesticides and cholinesterase inhibitors is accomplished by several distinct enzymes, which are collectively termed organophosphorus acid anhydrases (OPAs). These have been reviewed (DeFrank 1991), so that only a few additional comments are necessary. 

The reproducibility of a determination is a critical element of a standard method, so they are carefully written to ensure that they can be followed accurately by any qualified laboratory. The designated test biological RMs must not only be reproducible in their reactions to the performance tests, but they must also respond in a predicable manner. In order to guarantee that the same strain of microorganisms could always be available, many of these biological RMs have been deposited with the ATCC and other culture collections around the world. 

Seeds can be placed in water, and as imbibition occurs, the materials lost from seeds can be collected and analyzed qualitatively and quantitatively (10). Once germinated, seeds are commonly placed on some form of grid or support above the nutrient solution and, as the roots grow in the nutrient solution, it can be collected at intervals and the rhizodeposits analyzed. Seeds are often surface-sterilized to prevent utilization or alteration of the materials derived from the seed by contaminating microorganisms (e.g.. Ref. 11). 

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