1. Detection of starch adulteration (focus on polysaccharide indicators)
The active polysaccharides in mushroom extracts are mainly β-glucan, and the α-glucan content in natural products is usually less than 5%. Adulterators often add inactive α-glucan substances such as starch and dextrin to inflate the "total polysaccharide" content, which can be identified by the following methods:
Qualitative identification: Iodine test
Starch turns blue or blue-purple when exposed to iodine. Dissolve a small amount of extract sample in warm water and add iodine solution. Obvious discoloration indicates possible starch adulteration.
Quantitative identification: Megazyme kit detection
This kit can accurately determine the contents of β-glucan and α-glucan. Adulterated products (e.g., starch-added) show the characteristic of "high α-glucan content and low β-glucan content". Natural fruiting body products generally have α-glucan content below 5%, while mycelium with added excipients will also have excessive α-glucan.
Note: Mushroom powder contains both soluble and insoluble β-glucan, so its detection value is usually higher than that of hot-water extracts (which only contain more active soluble β-glucan), and the two cannot be directly compared.
2. Variety and source authenticity identification (DNA barcoding technology)
Some adulteration involves "shoddy substitution" (e.g., using low-cost mushrooms to impersonate high-value varieties), which can be verified at the genetic level. DNA barcode fragments such as ITS and tmH-psbA of mushrooms have been accurately decoded. Labs can extract sample DNA and compare it with standard sequence databases to directly identify the real variety source and avoid variety adulteration.
In summary, it is recommended to combine "qualitative + quantitative + genetic verification": first use the iodine test for preliminary starch adulteration screening, then use the Megazyme kit to quantify β-glucan purity, and finally confirm variety authenticity via DNA technology to fully ensure purity.
Wuhan Healthdream supports third-party sample testing and various polysaccharide detection methods, strictly following Megazyme kit standards to ensure the authenticity of polysaccharide content. For samples, please contact us at info@healthdreambio.com.