The Role Of Micro-Organisms In Biological Processes

Micro-organisms, like as bacteria, play a significant role within the natural cycling of materials and particularly in the decomposition of organic wastes. The role of micro-organisms is elaborated additionally here since they are also significant in the treatment of wastewater. What is waste for humans and higher vertebrates becomes a meaningful food substrate for the micro-organisms. Within both natural and engineered treatment systems, micro-organisms just like as bacteria, protozoa, fungi, and crustaceans play an necessary role in the conversion of organic waste to more stable less polluting substances. They create what is termed a 'food chain'. For instance, inorganic and organic substances in wastes are consumed through bacteria, fungi and algae. These are in turn consumed through protozoa and nematodes (some fungi however trap nematodes) and the latter through rotifers.

Micro-organisms are always present within the environment and given the right conditions of food availability, temperature and other environmental factors, they grow and multiply. Micro-organisms needs cellular building blocks, like as C (carbon), H (hydrogen), N (nitrogen), O (oxygen), P (phosphorus) and minerals for growth. These could be acquired through consuming organic substances holding these elements, or from inorganic materials, like as carbon dioxide, water, nitrate and phosphate. Micro-organisms also need energy. They acquire this through respiration. In this procedure, organic carbon is oxidised to release its energy. Oxygen or other hydrogen acceptors is required for the respiration process. Algae and photosynthetic bacteria could also utilise energy from sunlight, although certain kinds of bacteria could utilise energy from chemical reactions not including respiration. The building blocks and energy are used to synthesise more cells for growth and also for reproduction.

In the treatment of wastewater, three kinds of whole processes are distinguished to represent the conversion of organic wastes through micro-organisms. The categorization is based on whether the environment whereas the procedure takes place is aerobic, anaerobic or photosynthetic. Inside aerobic conditions (in the presence of oxygen), micro-organisms utilise oxygen to oxidise organic substances to acquire energy for management, mobility and the synthesis of cellular material. Inside anaerobic conditions (within the absence of oxygen), a micro-organisms utilise nitrates, sulphates and other hydrogen acceptors to acquire energy for the synthesis of cellular material from organic substances. The photosynthetic organisms use carbon dioxide as a carbon source, inorganic nutrients as sources of phosphate and nitrogen and utilise light energy to drive the conversion procedure.

Micro-organisms also generate waste products, some of that are desirable and some undesirable. Gases like as carbon dioxide and nitrogen are desirable, because they could be simply separated and do not generates pollution. Gases such as hydrogen sulphide and mercaptans, while simply separated need treatment for odour. The Micro-organisms' cellular materials are organic in nature and could also cause pollution. It would be desirable if a cellular materials have undergone self oxidation (endogeneous respiration utilising own body cells) to generates non-biodegradable materials that are associative stable. Self-oxidation is achieved while there is no substrate/food available.

Microbiological conversion reactions of organic waste within cellular material could be empirically represented as display in Figure 11.

                                               Figure 11: Microbiological Conversion Reactions