What is a nucleotide?
Nucleotides are a class of compounds consisting of purine or pyrimidine bases, ribose or deoxyribose and phosphoric acid. According to the different bases of nucleotide molecules, nucleotides can be divided into five types, namely 5′-adenine nucleotide (AMP), 5′-guanine nucleotide (GMP), 5′-cytosine nucleotide (CMP), 5′-uracil nucleotide (UMP) and 5′-hypoxanthine nucleotide (IMP).
Method of producing nucleotide
Currently, the synthesis methods of nucleotides mainly comprise chemical synthesis, microbial fermentation and enzymatic hydrolysis.
In the chemical production of nucleotides, mainly nucleosides are used for phosphate esterification. Since the reagents involved are expensive and use raw materials for toxic chemical synthesis, the process requirements are high, the environment is heavily polluted and the production costs are relatively high. In general, it is only used to produce some nucleotide derivatives with special purposes and is limited to laboratory scale. Large scale industrialised production presents certain difficulties.
The production of nucleotides by fermentation mainly uses the biosynthetic pathway of microbial strains to produce nucleotides. In order to produce nucleotides by microbial fermentation, biosynthetic pathways and regulatory mechanisms must be considered in order to select strains. Although production efficiency is high due to the problem of back mutations of strains and accumulation of products in the bacteria, feedback is also provided. Technical requirements such as control and regulation are relatively high. In the manufacturing process of fermentation there are special requirements for the composition of the medium and the addition of substances. In addition, the investment in building a factory is high and the product produced is single, so that it is limited to the production of very few products. Currently only inosine (IMP) and guanylate (GMP) have been industrialized.
Enzymatic hydrolysis produces nucleotides that use the P1 nuclease to degrade RNA to obtain a mixture of four nucleotides (AMP, GMP, CMP and UMP), and then separate and purify the four nucleotides by ion exchange resin. In addition, 5′-adenine nucleotide (AMP) is used as a substrate which is converted by adenylate deaminase to produce 5′-hypoxanthine nucleotide (IMP). The enzymatic hydrolysis process takes over the production of 5′-nucleotide, which has the advantages of a simple production process, abundant raw material sources and low cost. It is the manufacturing process with the longest history and the most mature technology.
Use of nucleotides
Nucleotides have a wide range of applications in industries such as food, medicine and agriculture.
In the food industry, when inosine and guanylate are mixed with sodium glutamate, the refreshing effect is improved by one to several tens times and has a good effect on the acidic, bitter, burnt and fishy taste. Disodium nucleotide (I + G) has developed into a third generation flavouring after monosodium glutamate and chicken essence. It is widely used in instant noodle spice packs, spices such as chicken essence, chicken powder and fresh soy sauce. In addition, nucleotides in baby food as baby food additives can significantly improve baby’s immunity, promote intestinal maturation, promote the synthesis of lipoproteins and polyunsaturated fatty acids, and reduce the incidence of colds and diarrhea in infants. Promotes normal growth and development of babies.
In the pharmaceutical industry, 5′-nucleotides can be used not only as drugs themselves, but also as raw materials for the production of many antiviral and antitumor drugs, such as the synthesis of the antiviral drugs ribavirin and acyclovir. These newly synthesized drugs are expected to become a new class of antiviral and anti-tumor drugs after sulfonamide drugs and antibiotics.
In the agricultural industry, nucleotides can be used as plant growth regulators in the production of plants, thereby increasing yield and weight. It can also be applied to feed additives, which has a very obvious effect on animal growth. In short, whether the use of nucleotides in the feed of crops or animals can reduce production costs and bring significant benefits.