Photosynthetic Bacteria (PSB for short) are the earliest prokaryotes on earth, ubiquitous in nature, and have a primitive light energy synthesis system. They carry out oxygen-free photosynthesis under anaerobic conditions. The general term for bacteria is a type of Gram-negative bacteria that does not have the ability to form spores. It is a type of bacteria that uses light as energy and can use organic matter, sulfide, ammonia, etc. in nature as a supply under anaerobic light or aerobic darkness conditions. Microorganisms that use hydrogen bodies and carbon sources to perform photosynthesis. Photosynthetic bacteria are widely distributed in soil, paddy fields, swamps, lakes, rivers and seas in nature, and are mainly distributed in anoxic areas where light can penetrate in aquatic environments. Basic introduction Chinese name: Photosynthetic Bacteria: Kingdom Bacteria Classification: Oxygenic photosynthetic bacteria and non-oxygenic photosynthetic bacteria Suitable water temperature: 15℃-40℃ Optimum water temperature: 28℃-36℃ English name: Photosynthetic Bacteria? Growth environment, Principle of action, characteristics, classification, cyanobacteria, purple bacteria, production applications, water purification, feed additives, reducing fish diseases, cultivating beneficial algae, usage methods, water spraying, feed addition, precautions, growth environment in aquaculture, It can degrade toxic substances such as nitrite and sulfide in water bodies, and achieve functions such as serving as bait, purifying water quality, preventing diseases, and serving as feed additives. Photosynthetic bacteria have strong adaptability, can tolerate high concentrations of organic wastewater, have certain tolerance and decomposition capabilities for phenol, cyanide and other poisons, and have strong decomposition and transformation capabilities. Its many characteristics make it of great application value in pollution-free aquaculture. Principle of action: Photosynthetic bacteria can perform photosynthesis in an environment with light and anoxia, use light energy to perform photosynthesis, and use light energy to assimilate carbon dioxide or other organic matter. Unlike green plants, their photosynthesis does not produce oxygen. There is only one photosystem in the photosynthetic bacterial cell, namely PSI. The original hydrogen donor for photosynthesis is not water, but H 2 S (or some organic matter). The result of its photosynthesis is to produce H 2 to decompose organic matter. It can also fix molecular nitrogen in the air to generate ammonia. During their own anabolic and metabolic process, photosynthetic bacteria have completed three extremely important chemical processes in the natural material cycle: hydrogen production, nitrogen fixation, and decomposition of organic matter. These unique physiological characteristics make them extremely important in the ecosystem. In addition, the cells also contain carbon storage substances glycogen and poly-β-hydroxybutyric acid, coenzyme Q, antiviral substances and growth-promoting factors. They have high feed value and have broad application prospects in the breeding industry. . Under anaerobic light conditions, PSB can use low-molecular organic compounds such as lower fatty acids, various dicarboxylic acids, alcohols, sugars, and aromatic compounds as electron acceptors for photosynthesis to grow photoheterotrophically. Under dark conditions, organic matter can be used as a respiratory substrate for aerobic or heterotrophic growth. Photosynthetic bacteria can not only use light energy to assimilate CO2 under anaerobic light, but also perform nitrogen fixation and produce hydrogen under certain conditions under the action of nitrogenase. In addition, some bacterial species can also produce hydrogen through the pyruvate metabolism system under dark anaerobic conditions. Photosynthetic bacteria can also utilize many organic substances such as organic acids. Alcohols and sugars convert certain toxic substances such as H2S and certain aromatic compounds. Through biological transformation, PSB can synthesize bacterial proteins that are non-toxic, have no side effects and are rich in various nutrients. This not only improves the ecological environment, but also provides high-quality feed raw materials for the breeding industry. The content of vitamin B12, biotin, pantothenic acid, carotenoids, chlorophyll, and folic acid related to hematopoiesis and hemoglobin formation in PSB bacteria, which can promote animal growth, is much higher than that of ordinary microorganisms, especially biotin D, which cannot be synthesized artificially. One isomer. These substances have significant physiological activity in the animal body. In aquaculture, the breeding pond can be divided into an aerobic zone and an anaerobic zone from the surface to the bottom according to the dissolved oxygen content in the water. The surface layer of organisms reproduces vigorously, and the water quality is generally good; the bottom layer accumulates fish and shrimp excrement and unconsumed food residues, and is rich in organic matter, causing a large number of microorganisms to multiply and consume a large amount of oxygen in the water, resulting in the formation of anaerobic conditions in the underground layer. In the environment, sulfate-reducing bacteria multiply in large numbers and produce hydrogen sulfide and acidic substances that are toxic to fish and shrimp.
The environment at the bottom of the breeding ground is exactly the conditions suitable for the survival of photosynthetic bacteria. Firstly, it has anaerobic conditions. Secondly, the light passes through the light filter of the aerobic water layer covering it, so that the photosynthetic bacteria can absorb 450-450 which is suitable for growth. 600nm wavelength light. Photosynthetic bacteria use underground fish and shrimp excrement, food residues, and toxic and harmful hydrogen sulfide and acidic substances as substrates to reproduce in large numbers, adjust pH, and reduce the content of ammonia nitrogen, nitrite nitrogen, and nitrate nitrogen, and reduce the accumulation of sludge at the bottom of the pond. The reduction is beneficial to the increase in the number of algae and microorganisms, allowing the water body to be purified. PSB can perform physiological functions such as photosynthesis, aerobic respiration, nitrogen fixation, and carbon fixation, and is rich in nutrients such as proteins, vitamins, growth-promoting factors, and immune factors. It is functionally comparable to antibiotics and is safer. It is Bioengineering is one of the promising research areas. Photosynthetic bacteria preparations also have unique disease resistance and growth promotion functions, which greatly improve production performance and show increasing potential in application. Others have broad application prospects in water purification, fish and shrimp breeding, livestock and poultry breeding, organic fertilizers and the development of new energy. Characteristics It is worth noting that photosynthetic bacteria have photosynthetic pigments such as chlorophyll, but do not have chloroplasts. Photosynthetic bacteria Photosynthetic bacteria are widely distributed in soil, paddy fields, swamps, lakes, rivers and seas in nature, and are mainly distributed in anoxic areas where light can penetrate in aquatic environments. The suitable water temperature for photosynthetic bacteria is 15-40℃, and the optimal water temperature is 28-36℃. The protein content in its cell dry matter is as high as over 60%, and its protein amino acid composition is relatively complete. The cells also contain a variety of vitamins, especially B vitamins, which are extremely rich in VB2, folic acid, pantothenic acid, and biotin. It is relatively high and also contains a large amount of physiologically active substances such as carotenoids and coenzyme Q. Therefore, photosynthetic bacteria have high nutritional value, which is the material basis for their use as water cultivation bait and as feed additive in aquaculture. Classification Bacteria that can produce energy through photosynthesis in nature are divided into oxygen-producing photosynthetic bacteria (cyanobacteria, prochlorobacteria) and non-oxygen-producing photosynthetic bacteria (purple bacteria and green bacteria) according to the photosynthetic pigments and electron donors they contain. . Cyanobacteria The photosynthesis of Cyanobacteria is different from that of traditional photosynthetic bacteria, but more similar to that of green plants. First of all, cyanobacteria are oxygen-producing photosynthetic bacteria, and the carbon source is only carbon dioxide. It has two photosystems, PSI and PSII. The original hydrogen donor of photosynthesis is water, and the result of photosynthesis is the production of oxygen. Cyanobacteria are a type of photosynthetic bacteria that contain chlorophyll a, use water as a hydrogen donor and electron donor, convert light energy into chemical energy through photosynthesis, and assimilate CO2 into organic matter. Because they have the same photosynthetic system as plants, they were historically classified as algae by phycologists, called cyanobacteria. Research on the cell structure of cyanobacteria shows that the nucleus of cyanobacteria does not have a nuclear membrane and no mitotic apparatus. The cell wall is composed of peptidoglycan and lipopolysaccharide layers containing diaminopimelic acid. It is Gram stain-negative and secretes a mucus layer. The capsule or sheath is formed, and the cell contains 70S ribosomes. Although it has the photosynthetic pigment of chlorophyll, it does not form chloroplasts. The part that performs photosynthesis contains chlorophyll a, β-carotene, carotenoids, and phycobilin (including phycocyanin and phycoerythrin) thylakoids. These characteristics of cyanobacteria that are similar to those of prokaryotes make them members of the bacterial family. The pigment dominated by phycocyanin gives the cells a special blue color, hence the name cyanobacteria. According to morphology, it can be divided into 5 major groups, including 29 genera. The cell sizes of cyanobacteria vary widely. The smallest one, Synechococcus, has a diameter of only 0.5-1 μm, while the diameter of Oscillatoria can exceed 60 μm. Cyanobacteria are widely distributed in nature and are common in waters such as rivers, lakes and seawater. The nutrition of cyanobacteria is extremely simple and does not require vitamins. They use nitrate or ammonia as a nitrogen source. Most of them can fix nitrogen. Cultivating cyanobacteria in rice fields can maintain and improve soil fertility. Some experiments have proven that cyanobacteria can be used as food and supplementary nutrients to treat diseases such as cirrhosis, anemia, cataracts, glaucoma, and pancreatitis. It also has certain effects on diabetes and hepatitis.
Cyanobacteria are different from the oxygen-emitting photosynthesis of eukaryotes. They may be the first oxygen-producing photosynthetic organisms in the evolution of life on earth. They play a key role in the transition from anaerobic to aerobic life on earth and the evolution of eukaryotes. landmark role. Purple bacteria Purple bacteria are a group of photoautotrophic bacteria that contain bacteriochlorophyll and carotenoids, are capable of photosynthesis, have diverse photosynthetic inner membranes, use sulfide or sulfate as electron donors, and deposit sulfur. Because it contains different types of carotenoids, the cell culture fluid is purple, red, orange-brown, and yellow-brown, so it is called purple bacteria. Rhodospirillum, Rhodopseudomonas and Rhodomicrobium were once considered to be unable to use sulfide as an electron donor to reduce CO2 to form cellular substances, so they have always been called non- Sulfur purple bacteria. It was later discovered that most of these bacteria can still utilize low concentrations of sulfide and are now classified as purple sulfur bacteria. They are mostly found in freshwater, seawater and high-salt aquatic environments containing soluble organic matter and low oxygen pressure. They are also commonly found in moist soil and rice fields. Purple Bacteria Production and Purification Water Quality With the development of the aquaculture industry, the output of aquaculture units has increased significantly. However, the water quality is seriously polluted, especially in the later stages of breeding. The content of organic matter, ammonia and nitrite in the water is relatively high, which seriously affects the growth of fish. . After photosynthetic bacteria are applied to the water body, they can degrade residual feed, fish feces and other organic matter in the water body; at the same time, they can also absorb and utilize harmful substances such as ammonia, nitrite, and hydrogen sulfide in the water body. The application of photosynthetic bacteria can effectively avoid the accumulation of solid organic matter and harmful substances and play a role in purifying water quality. The photosynthetic bacteria used in aquaculture are mainly some species of the photoheterotrophic family Rhodospirillaceae, such as Rhodop seudanonas palustris; in nature, freshwater and seawater usually contain Nearly a hundred PSB bacteria, photosynthetic bacteria use organic acids, amino acids, ammonia, sugars and other organic matter and hydrogen sulfide as oxygen donors, obtain energy through photosynthetic phosphorylation, and can directly use it to degrade organic matter under light conditions in water. and hydrogen sulfide and allow itself to proliferate while purifying water bodies. Feed additives Photosynthetic bacteria are a kind of bacteria with rich nutrition and high nutritional value. The bacteria are rich in amino acids, folic acid, B vitamins, especially vitamin B12 and biotin, as well as the physiologically active substance coenzyme Q. The volume of photosynthetic bacteria is one-twentieth that of chlorella, making it particularly suitable as opening bait for newly hatched fish. Using photosynthetic bacteria as opening bait can greatly improve the survival rate of fry. Photosynthetic bacteria can also be added to feed as feed additives. The enzymes contained in photosynthetic bacteria can promote the digestion and absorption of feed by fish, improve feed utilization, reduce the feed coefficient, and can also significantly increase the growth rate of fish. Reduce fish diseases. After photosynthetic bacteria are applied to the water body, they quickly multiply and become the dominant bacterial population in the water body. This not only improves the water quality, but also inhibits the growth and reproduction of harmful bacteria and reduces the number of harmful bacteria, thus reducing the occurrence of fish diseases. . Photosynthetic bacteria are very effective in preventing diseases. Cultivate beneficial algae. After photosynthetic bacteria are added to the water body, diatoms, chlorella and other algae that fish like to eat become the dominant algae, while harmful algae such as cyanobacteria are suppressed. Photosynthetic bacteria can utilize a large amount of ammonia nitrogen in the water and can effectively avoid the occurrence of "algae blooms", such as the proliferation of cyanobacteria. Instructions for use Water spraying Water spraying is suitable for improving water quality, preventing fish diseases and cultivating fine algae. Choose a sunny morning or afternoon, dilute the photosynthetic bacteria with pool water, and sprinkle it evenly throughout the pool. Due to the high bacterial content of this product, each milliliter of bacterial solution should contain more than 10 billion photosynthetic bacteria, so the application rate per acre is 1.5 kg - 3 kg. The frequency of applying photosynthetic bacteria is determined according to the water quality. If the water quality is good, it can be applied once every 15 days; if the water quality is fertile and the water quality is poor, especially in high-yield ponds in the later stages of breeding, it should be applied every 7-10 days. Feed addition: When photosynthetic bacteria are used as feed additives, the photosynthetic bacteria liquid can be sprayed into the feed and mixed well. The dosage of the bacterial liquid is 1% of the feed amount, and it is ready for use. Notes (1) Photosynthetic bacteria can be used in fry ponds, fingerling ponds, adult fish ponds, broodstock ponds, fishing ponds and overwintering ponds. In addition to using fish ponds, shrimp ponds can also be used to get twice the result with half the effort.
(2) If disinfectant has been used in the water body, photosynthetic bacteria should be used after 48 hours. In fact, consistent use of photosynthetic bacteria is much more effective than frequent use of disinfectants. (3) The effect of using photosynthetic bacteria in combination with manure is more direct and obvious, especially when used in fish fry and fingerling breeding tanks, the increase in production and efficiency is particularly significant. (4) The propagated photosynthetic bacteria should be used as soon as possible and should not be stored at room temperature for more than 6 months. (5) Photosynthetic bacteria are prohibited from being stored in metal containers.