Amino acids are organic compounds that contain both amino and carboxylic acid functional groups (figure 1). Amino acids are known as the building blocks of protein and they find various applications in the production of foods, animal feeds and pharmaceuticals. Recently, with the fast development of metabolic engineering and synthetic biology technologies, the metabolic engineering for production of amino acids has been flourishing.
Fig. 1 Structure of amino acids
There are over 500 amino acids in nature, while only 20 of them directly code with human genetics (Figure 2). Broadly, these 20 amino acids can be sorted into two groups: essential and non-essential. Essential amino acids, also known as indispensable amino acids, are amino acids that humans and other vertebrates cannot synthesize from metabolic intermediates. Whereas non-essential amino acids can be synthesized by the body.
Fig. 2 Non-essential and essential amino acids
At present, amino acids are mainly produced through three different routes, namely, extraction from protein-hydrolysates, chemical synthesis and microbial processes (enzymatic synthesis and fermentation). The different amino acids production methods are compared in table 1 [1].
Table 1 Comparison among different amino acid production methods
| Methods | Principle | Advantages | Disadvantages |
|---|---|---|---|
| Extraction from protein hydrolysates | An amino acid can be separated from the others present in the protein-hydrolysates if its properties are different from the others |
| |
| Chemical synthesis | Amino acids obtained through a chemical reaction |
| |
| Enzymatic synthesis | Application of proteases to peptide hydrolysis |
| |
| Fermentation | Microorganisms convert the sugars present in a substrate into amino acids |
|
The fermentation process is becoming one of the most promising processes for amino acids commercial production because of the new genetic engineering tools applied to maximize yield, specificity and productivity of the target compounds. An example of the fermentation process is showed in figure 3 [2].
Fig. 3 Example of amino acid fermentation and downstream process flowchart
Amino acids can be used to enhance the flavor of food and enhance nutrition. Additionally, amino acids are widely used in the medical and healthcare industry, cosmetic industry, and biopharmaceutical industry. Common applications are as followings.
Alfa Chemistry is a professional supplier of amino acids and derivatives. For high quality products, professional technical service, use suggestion and latest industry news, please feel free to contact us.
References
Please kindly note that our products are for research use only.
