Thursday, January 31, 2008

Uderstanding Bacteria and Enzymes

The adaptable nature of bacteria makes it possible to exploit particular strains for their beneficial qualities. The natural biodegradation of organic waste can be greatly enhanced by the introduction of naturally occurring, non genetically engineered, non pathogenic bacteria. Biodegrading "specialists" are scientifically selected for their exceptional enzyme production and long term stability.

In the natural environment, both bacteria, and the enzymes they produce, play a significant part in biodegradation: Bacteria produce the enzymes essential for metabolizing the food source (organic waste) into energy necessary for further growth of the living organism. Enzymes facilitate the phase of metabolism in which complex compounds are broken into simpler ones (catabolism). This, in turn, speeds the process of converting the food source into an available energy supply for bacterial growth and reproduction (and continuous enzyme production).

A. BACTERIA

1. General Background
Although some bacteria may cause certain diseases, many more bacteria are not only harmless, but they actually are very beneficial. The positive influence of these numerous useful microscopic organisms in our biosphere is incalculable. For example, without bacteria, the soil would not be fertile (and all plants and animals ultimately are dependent upon soil fertility for life sustaining materials). Various species of bacteria are concerned in the decomposition of organic matter, fermentation, and the fixing of atmospheric nitrogen. Many of the common bacteria of air, soil and water are capable of digesting dead organic materials, proteins, carbohydrates, fats and grease, and cellulose breaking them down to simpler molecules and in utilizing these substances. This impressive ability of bacteria as a group to produce such a great diversity of biochemical changes and end results constitutes one of the outstanding facts of the natural world.

2. Rate of Multiplication
Given reasonable and suitable conditions for growth, the rate of asexual multiplication of bacteria is very rapid; it has been found that a cell divides every 20 to 30 minutes. So, assuming that conditions are conducive to a rate of one division every 30 minutes, a single individual cell will have produced 4 cells at the end of the first hour, 16 at the end of two hours, and about one million (1,000,000) at the end of fifteen (15) hours. Thus, when products containing millions of selected bacteria per milliliter are introduced under suitable conditions, the eventual bacterial growth is astronomical, and, by virtue of the presence of such great numbers of efficient, beneficial bacteria, the presence and growth of less productive and often harmful, naturally occurring bacteria are greatly reduced by competitive exclusion. Simply stated, the selected, introduced bacteria are more efficient and out compete the naturally occurring bacteria for the food source.

3. Conditions Affecting Growth of Bacteria

a. Food requirements. Bacteria must obtain from their environment all nutrient materials necessary for their metabolic processes and cell reproduction. The food must be in solution and must pass into the cell.

b. Temperature. For every bacterium, there 'are certain cardinal points of temperature at which growth is most rapid. Although different bacterial species differ widely, the optimum growth temperature for most bacteria lies between 5° C and 55° C (41 ° F to 131 ° F). Growth may slow at temperatures below 5°C (41 ° F) and cell damage may occur at temperatures above 60° C (140° F). The ordinary cells (non spores) are damaged at temperatures of 60° to 80° C (122° F to 140° F); hence a single boiling of a fluid or even pasteurization (application of a heat of 63° C or 145° F) is sufficient to eliminate them. Bacterial spores, however, must be subjected to very prolonged heating at higher temperatures before they are distressed.

c. pH. Each bacterium has a pH range within which growth is possible. Growth will occur in environments that have pH values between 4.5 and 10; the optimum pH value differs greatly between species but an environment kept close to neutral (pH 7) will sustain most bacterial species.

d. Moisture. Bacteria require moisture. The importance of moisture for bacterial growth will be seen clearly if it is realized that bacteria have no mouth parts and all their food must be absorbed in a soluble form by the process of diffusion through the cell wall; without sufficient moisture, therefore, the inflow of food and the outflow of excreta becomes impossible.

e. Oxygen. Bacteria of various kinds exhibit wide differences in their relation to oxygen of the air. Some need oxygen for respiration and cannot grow unless it is provided. These are known as aerobes. Others grow only in the absence of free oxygen and are unable to use it in their respiration, they are called anaerobes. Still others can grow under either condition and are termed facultative.

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