Objective  A molecular biology identification method to detect common plant-derived functional ingredients in health food products using genetic barcodes was developed.

  Method   By means of retrospective investigation, 5 common health food raw materials in China, i.e., American ginseng (Panax quinquefolius), Dendrobium candidum, rhodiola (Rhodiola nobilis), wolfberries (Lycium barbarum L.), and ginseng (Radix Ginseng), were firstly tested for functional ingredients using the best extraction method on the target DNA. A stable, efficient, and accurate PCR reaction system was constructed with primer sequence designed based on the conservative characteristics of ITS2 internal transcribed spacer and components of each substance adjusted and optimized. Molecular identification on health food products of various forms was tested using the developed method.

  Result   The innovative application of a modified CTAB method afforded successful extraction of the target DNA in health food materials as well as products at commonly formulated dosages. The PCR amplified with the detection sensitivity on nucleic acids of American ginseng, D. candidum, and rhodiola reached 1 ng·μL⁻¹, and of wolfberries and ginseng 0.1 ng·μL⁻¹.

  Conclusion   By using the ITS gene barcodes obtained through the DNA extraction and PCR amplification, the key functional ingredients from plant materials such as American ginseng, ginseng, D. candidum, wolfberries, and rhodiola rosea could be identified for authentication of health food products in the forms of pills, tablets, and concoctions.