Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Microbes contamination

The extension of the useful storage life of plant and animal products beyond a few days at room temperature presents a series of complex biochemical, physical, microbial, and economic challenges. Respiratory enzyme systems and other enzymes ia these foods continue to function. Their reaction products can cause off-davors, darkening, and softening. Microbes contaminating the surface of plants or animals can grow ia cell exudates produced by bmises, peeling, or size reduction. Fresh plant and animal tissue can be contaminated by odors, dust, iasects, rodents, and microbes. [Pg.458]

Phytoremediation is the use of plants to treat contaminated soil or groundwater. Many different plant-contaminant or plant-microbe-contaminant interactions can lead to reducing the threat posed by contaminants. To best understand how plants can reduce contaminant threat, comprehending the role of plants and their interactions with the environment overall is important. If the plant processes are recognized, then the application of plants to remedy contaminated sites is clear and logical. In this work, the ecological role of plants will be outlined, and then the ways in which plant-environment interactions can be exploited in mitigating the threat of contaminants in our environment are discussed. [Pg.2139]

Microorganisms are ubiquitous, thus microbial contamination is the rule the total absence of microbes, ie, sterility, is the exception. Many microorganisms might be considered mainstream, growing under typical ambient conditions, but there are almost always strains that are capable of surviving and multiplying under the extremes of pH, salinity, pressure, and temperature. [Pg.91]

Ex situ bioremediation may use various biological wastewater treatment processes, soil piles, or land appHcation. With in situ bioremediation, the basic process is the same microbes, soil, and water working together as a bioreactor. Where the in situ techniques differ are in how contaminants and microbes are brought in contact and how oxygen, nutrients, and other chemical supplements ate distributed in the soil—water—air matrix. Typical in situ bioremediation techniques include natural or intrinsic attenuation, air sparging, and bioventing. [Pg.170]

No more than 5.0% samples total coliform-positive in a month, (For water systems that collect fewer than 40 routine samples per month, no more than one sample can be total coliform-positive). Every sample that has total coliforms must be analyzed for fecal coliforms. There may not be any fecal coliforms or E. coli. Fecal coliform and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Disease-causing microbes (pathogens) in these wastes can cause diarrhea, cramps, nausea, headaches, or other symptoms. These pathogens may pose a special health risk for infants, young children, and people with severely compromised immune systems. [Pg.25]

Similar to other types of water treatment, AC filtration is effective for some contaminants and not effective for others. AC filtration does not remove microbes, sodium, nitrates, fluoride, and hardness. Lead and other heavy metals are removed only by a very specific type of AC filter. Unless the manufacturer states that its product will remove heavy metals, one should assume that the AC filter is not effective in removing them. [Pg.409]

For sterile conditions Xa is zero, because no microbe is present in the feed stream and the feed is sterile without any contamination. [Pg.156]

Microbial contaminants will usually need to be able to attack ingredients of a medicine and create substrates necessary for biosynthesis and energy production before they can replicate to levels where obvious spoilage becomes apparent since, for example, 10 microbes will have an overall degradative effect around 10 time faster than one cell. However, growth and attack may well be localized in surface moisture films or very unevenly distributed within the bulk of viscous formulations such as creams. Early... [Pg.359]

Contamination is not restricted to natural products. Organic pigment powders are often precipitated from aqueous solutions and washed with water prior to drying. These have been found to contain high numbers of microbes and have been implicated in contamination instances. [Pg.71]

Lenses are exposed to a broad spectrum of microbes during normal wear and handling and become contaminated relatively quickly. Failure to remove microorganisms effectively from lenses can cause ocular infections. Ocular infections, particularly those caused by pathogenic microbes, such as P. aeruginosa, can lead to the loss of the infected eye if left untreated. [Pg.469]

Bioremediation systems in operation today rely on microorganisms indigenous to contaminated sites. The two main approaches, based on the actions of native microbial communities, are biostimulation and intrinsic bioremediation. In biostimulation, the activity of native microbes is encouraged, creating (in situ or ex situ) the optimum environmental conditions and supplying nutrients and other chemicals essential for their metabolism. The vast majority of bioremediation projects are based on this biostimulation approach. Intrinsic bioremediation is a remedial option that can be applied when there is strong evidence that biodegradation will occur naturally over time without any external stimulation i.e., a capable microbial community exists at the site, the required nutrients are available, and the environmental conditions are favorable. An additional prerequisite is that the naturally... [Pg.534]

It has long been known that certain microbes can alter the oxidation state of some toxic metals, mainly by reducing them to a lower oxidation state, and this chemical transformation can be used for the bioremediation of contaminated soils. Three main mechanisms are involved in the... [Pg.536]


See other pages where Microbes contamination is mentioned: [Pg.576]    [Pg.785]    [Pg.311]    [Pg.784]    [Pg.1323]    [Pg.278]    [Pg.670]    [Pg.259]    [Pg.576]    [Pg.785]    [Pg.311]    [Pg.784]    [Pg.1323]    [Pg.278]    [Pg.670]    [Pg.259]    [Pg.38]    [Pg.139]    [Pg.184]    [Pg.458]    [Pg.458]    [Pg.303]    [Pg.10]    [Pg.10]    [Pg.12]    [Pg.388]    [Pg.342]    [Pg.346]    [Pg.215]    [Pg.51]    [Pg.138]    [Pg.362]    [Pg.365]    [Pg.368]    [Pg.368]    [Pg.371]    [Pg.413]    [Pg.53]    [Pg.77]    [Pg.201]    [Pg.237]    [Pg.390]    [Pg.421]    [Pg.535]    [Pg.535]    [Pg.551]    [Pg.576]   
See also in sourсe #XX -- [ Pg.252 ]




SEARCH



Microbes

© 2024 chempedia.info