Apricot Seeds(Semen Armeniacae Amarum) are the seeds from Rosaceae family plants such as Prunus armeniacaL. AJlsu Maxim, Siberian apricot (Prunus sibirica), and Prunus Mandshunca (Maxim.) Koehne or Apricot Prunus armeniacaL. It is rich in fatty acids, amino acids and other active ingredients such as amygdalin and amygdalase. Amygdalin is a secondary metabolite widely distributed throughout the plant kingdom and consumed by humans. It also can be found in various food products, including raw almonds, apricots, and celery, it is also found in apple, cherry, flaxseed, nuts, and some seeds. Amygdalin belongs to a class of compounds called cyanogenic glycosides.

Amygdalin is an organic chemical composed of sugar (sucrose) and a molecule with a cyanide moiety. It has various benefits in clinical. induces the death of cancer cells in several ways. The chemical increases the expression of glutathione peroxidase and suppresses the activity of superoxidase. It is also a potent analgesic and anti-inflammatory agent. It may also be helpful in the treatment of dry eye disease. However, the cyanide component can cause a coma. Therefore, if you’re thinking about trying it, consult your doctor.

Amygdalin is extracted in a variety of ways, including water extraction, solvent extraction, microwave radiation, Enzymatic extraction and other methods, of which water extraction, solvent extraction (methyl alcohol, ethanol extraction) and supercritical CO2 extraction are commonly used. Water and organic solvent extraction methods have a low cost but a little low efficiency. Supercritical extraction method has good separation effect but high extraction cost, so it is limited in practical application.

Ethanol extraction method

This method is used most and the effect is better. After crushing and degreasing, the raw material of bitter almond was extracted by reflux with 95% ethanol. Since the solubility of amygdalin in cold ethanol is small and that in hot ethanol is very large, ethanol can be used as a crystallization solvent to extract amygdalin, and the crude amygdalin can be obtained by crystallization or decompression distillation.

Water extraction

Water is a typical strong polar solvent with strong penetrability to plant tissue, high extraction efficiency and safety. The essence of amygdalin extraction by water is the mass transfer process of amygdalin from amygdalin inside amygdalin to water. When amygdalin was water-extracted, the content of protein in the almond extract was high, which made the extract easy to mold and deteriorate. It is difficult to purify amygdalin due to a large amount of material (10: 1) in water extraction. In spite of the improved efficiency of hot water extraction, most D-amygdalin was converted to isomicamygdalin in a ratio of nearly 1:1. The yield of 100 min extraction of amygdalin at 37 degC was 2.2 mg 100 g A1. Using water as a solvent yielded 6.8 mg 100 g A1.

In addition, there are water-ethanol extraction methods, methanol extraction methods, ultrasonic extraction, and microwave extraction method. Each method has its advantages and disadvantages, you can choose the right methods by your specific consideration, like equipment, time, cost and so on. The whole extraction process of apricot seeds includes drying, enzymatic inactivation, crushing, degreasing and others, among which enzymatic inactivation and degreasing processes determine the quality of almond extract. The enzyme amygdalin lyase contributes to the degradation of amygdalin, resulting in its split into prunasin and glucose. Hydroxynitrile lyase then pulls the two components apart. This type of enzyme-assisted degradation of amygdalin occurs in an acidic environment.

Purification

Amygdalin is isolated by removing impurities in the raw material. This method consists of two steps: a first extraction and a second extraction. The first extraction step usually yields the largest concentration of amygdalin, and the second extraction step only contains a small amount.

HPLC Test Method

The most effective way to extract amygdalin is via the high-performance liquid chromatographic method (HPLC), which requires a relatively short extraction time and a small amount of solvent. To validate the HPLC method, NMR (1H and 13C), FTIR, and UV-vis spectroscopy can be used to determine the structure of amygdalin. The method has been optimized for use in food analyses and has been applied to commercially available food products.